ALBERT

Description: Observations of large and abrupt climate changes recorded in Greenland ice cores have spurred a search for clues to their cause. This search has revealed that at six times during the last glaciation, huge armadas of icebergs launched from Canada spread across the northern Atlantic Ocean, each triggering a climate response of global extent.

Description: WHILE ammonites and all other ectocochleate cephalopods became extinct, nautiloids survived relatively unchanged from the Ordovician, suggesting that they are unusually well adapted to their niche. Here we obtain high-resolution tracks of Nautilus positions and depths, combined with telemetered jet pressures, which clarify both its lifestyle and economics. Nautilus is more active in nature than in captivity1, but its energy costs are lower than projected2,3. Viewing Nautilus as 'vertic', rather than benthic, resolves this contradiction. Records show that the cost of transport is the same in any direction within a vertical plane. Living on a reef face swept by a lateral current means that vertical movements4,5 sample large areas for chemical trails. A detected trail can be followed upcurrent in the slow-moving boundary layer, but no effort is wasted on horizontal movement without good prospects for food; long-range movements are downcurrent and made by drifting. Once fed, a Nautilus can reduce its energy costs by moving to deeper, cooler waters, where a single meal can last for months.

Description: THE vestimentiferan tubeworm Riftia pachyptila is found around hydrothermal vent areas in the deep sea. Intracellular bacterial chemoautotrophic symbionts use the oxidation of sulphide from the effluent of the vents as an energy source for CO2 fixation. They apparently provide most or all of the nutritional requirements for their gutless hosts1–5. This kind of symbiosis has since been found in many other species from various other phyla from other habitats6–9. Here we present results that the bacteria of R. pachyptila may cover a significant fraction of their respiratory needs by the use of nitrate in addition to oxygen. Nitrate is reduced to nitrite, which may be the end product (nitrate respiration)10 or it may be further reduced to nitrogen gas (denitrification)11. This metabolic trait may have an important role in the colonization of hypoxic habitats in general by animals with this kind of symbiosis.

Description: THE supply of dissolved inorganic carbon (DIC) is not considered to limit oceanic primary productivity1, as its concentration in sea water exceeds that of other plant macronutrients such as nitrate and phosphate by two and three orders of magnitude, respectively. But the bulk of oceanic new production2 and a major fraction of vertical carbon flux is mediated by a few diatom genera whose ability to use DIG components other than CO2, which comprises 〈 1% of total DIC3, is unknown4. Here we show that under optimal light and nutrient conditions, diatom growth rate can in fact be limited by the supply of CO2. The doubling in surface water pCO2 levels since the last glaciation from 180 to 355 p.p.m.5,6 could therefore have stimulated marine productivity, thereby increasing oceanic carbon sequestration by the biological pump.

Description: Oxygen and carbon isotope measurements were carried out on tests of planktic foraminilers N. pachyderma (sin.) from eight sediment cores taken from the eastem Arctic Ocean, the Fram Strait, and the Iceland Sea, in order to reconstruct Arctic Ocean and Norwegian-Greenland Sea circulation patterns and ice covers during the last 130,000 years. ln addition, the influence of ice, temperature and salinity effects on the isotopic signal was quantified. Isotope measurements on foraminifers from sediment surface samples were used to elucidate the ecology of N. pachyderma (sin.). Changes in the oxygen and carbon isotope composition of N. pachyderma (sin.) from sediment surface samples document the horizontal and vertical changes of water mass boundaries controlled by watertemperature and salinity, because N. pachyderma (sin.) shows drastic changes in depth habitats, depending on the water mass properties. It was able to be shown that in the investigated areas a regional and spatial apparent increase of the ice effect occurred. This happened especially du ring the termination 1 by direct advection of meltwaters from nearby continents or during the termination and in interglacials by supply of isotopically light water from rivers. A northwardly proceeding overprint of the "global" ice effect, increasing from the Norwegian-Greenland Sea to the Arctic Ocean, was not able to be demonstrated. By means of a model the influence of temperature and salinity on the global ice volume signal during the last 130.000 years was recorded. In combination with the results of this study, the model was the basis for a reconstruction of the paleoceanographic development of the Arctic Ocean and the Norwegian-Greenland Sea during this time interval. The conception of a relatively thick and permanent sea ice cover in the Nordic Seas during glacial times should be replaced by the model of a seasonally and regionally highly variable ice cover. Only during isotope stage 5e may there have been a local deep water formation in the Fram Strait.

Description: ALTHOUGH anthropogenic emissions of carbon dioxide have today created a greater atmospheric CO2concentration in the Northern than in the Southern Hemisphere, a comparison of interhemispheric CO2 profiles from 1980 and 1962 led Keeling and Heimann1,2 to conclude that, before the Industrial Revolution, natural CO2 sources and sinks acted to set up a reverse (south to north) gradient which drove about one gigatonne of carbon each year through the atmosphere from the Southern to the Northern Hemisphere. At steady state, this flux must have been balanced by a counter flow of carbon from north to south through the ocean. Here we present a means to estimate this natural flux by a separation of oceanic carbon anomalies into those created by biogenic processes and those created by CO2 exchange between the ocean and atmosphere. We find that before the Industrial Revolution, deep water formed in the northern Atlantic Ocean carried about 0.6 gigatonnes of carbon annually to the Southern Hemisphere, providing support for Keeling and Heimann's proposal. The existence of this oceanic carbon pump also raises questions about the need for a large terrestrial carbon sink in the Northern Hemisphere, as postulated by Tans et al.3, to balance the present global carbon budget.

Description: IN 1989, the submersible Nautile discovered one of the most active hydrothermal fields on the modern ocean floor, in the Lau back-arc basin (Fig. 1). The field contains high-temperature white and black smokers, and as we report here, its characteristics contrast strongly with those of the hydrothermal fields found at normal mid-ocean ridges. The main differences are the acidity (pH as low as 2), chemistry and temperature (up to 400 °C) of the hydrothermal fluids, the composition of the ore deposits, and the volcanic and tectonic environments. The fluids also have very high concentrations of trace metals, and primary gold is present in the accompanying mineral deposits. Our data show that these back-arc deposits in the Lau Basin are intermediate between typical mid-ocean-ridge mineralization and massive sulphide deposits of the Kuroko type.

Description: The response of the global climate system to smoke from burning oil wells in Kuwait is investigated in a series of numerical experiments using a coupled atmosphere–ocean general circulation model with an interactive soot transport model and extended radiation scheme. The results show a decrease in surface air temperature of ~4 °C in the Gulf region. Outside this region the changes are small and statistically insignificant. No weakening of the Indian summer monsoon is observed.

Description: ISOTOPE ratios and concentrations of incompatible trace elements are remarkably successful in discriminating the tectonic origin and magmatic source components for basalts1–5. But problems remain with discriminating the tectonic origin of some tholeiites, especially where field relations and other geological evidence are ambiguous. For example, the tectonic origin of basalts from the Troodos ophiolite (Cyprus) has been debated for several decades. Most workers have been unable to distinguish between an island-arc and/or back-arc origin for the ophiolite6–8. Here we use volatile, K2O and TiO2 contents from ∼250 fresh submarine volcanic glasses to discriminate between tholeiites from different tectonic regimes. K2O÷H2O ratios are lower (〈0.70) in spread ing-centre glasses than in those from island arcs and intraplate oceanic islands. Back-arc-basin basalts can generally be separated from mid-ocean-ridge basalts by their high H2O contents. Using this information, we show that some fresh glasses from the Troodos ophiolite have a clear back-arc-basin affinity.

Description: RECENT advances in 40Ar/39Ar dating1,2 have made it possible to date individual K-feldspar grains from Pleistocene tephra, a capability that greatly improves the reliability and temporal resolving power of the method. Here we apply these new techniques to the dating of a phonolite tephra from the East Eifel volcanic field in West Germany, which is sandwiched between loess and palaeosol (alfisol) deposits, and which was therefore erupted during the transition from a glacial to an interglacial period. Our age estimate for this transition is 215±4 kyr (1 σ), which has important implications for the marine δ18O timescale and for models of global climate change during the Pleistocene. The results show that single-grain dating can detect and compensate for the large quantities of xenocrystic contaminants which are found in many tephra deposits. This technique could be used to date the tephra layers found in marine sediment cores and the results could greatly enhance the reliability of the marine δ18O timescale for more rigorous Fourier analysis testing of the Milankovitch hypothesis.

Description: ROOTH proposed that the Younger Dryas cold episode, which chilled the North Atlantic region from 11,000 to 10,000 yr BP, was initiated by a diversion of meltwater from the Mississippi drainage to the St Lawrence drainage system. The link between these events is postulated to be a turnoff, during the Younger Dryas cold episode, of the North Atlantic's conveyor-belt circulation system which currently supplies an enormous amount of heat to the atmosphere over the North Atlantic region2. This turnoff is attributed to a reduction in surface-water salinity, and hence also in density, of the waters in the region where North Atlantic Deep Water (NADW) now forms. Here we present oxygen isotope and accelerator radiocarbon measurements on planktonic foraminifera from Orca Basin core EN32-PC4 which reveal a significant reduction in meltwater flow through the Mississippi River to the Gulf of Mexico from about 11,200 to 10,000 radiocarbon years ago. This finding is consistent with the record for Lake Agassiz which indicates that the meltwater from the southwestern margin of the Laurentide Ice Sheet was diverted to the northern Atlantic Ocean through the St Lawrence valley during the interval from ~11,000 to 10,000 years before present (yr BP).

Description: Abrupt changes in climatic conditions have been seen at high latitudes in the North Atlantic and the Antarctic at 13 kyr BP. It is important to determine whether this abrupt change was confined to high-latitude regions or whether it was global. Here we present results demonstrating an abrupt change in the rate and character of sedimentation in the South China Sea at the close of the last glacial period. Radiocarbon dating and its position in the oxygen isotope shift suggest that this change may be coincident with the changes found at high latitudes.

Description: Abrupt changes in climatic conditions have been seen at high latitudes in the North Atlantic1 and the Antarctic2,3 at 13 kyr BP. It is important to determine whether this abrupt change was confined to high-latitude regions or whether it was global. Here we present results demonstrating an abrupt change in the rate and character of sedimentation in the South China Sea at the close of the last glacial period. Radiocarbon dating and its position in the oxygen isotope shift suggest that this change may be coincident with the changes found at high latitudes.

Description: Perhaps the most significant event in the Cretaceous record of the carbon isotope composition of carbonate1,2, other than the 1–2.5 ‰ negative shift in the carbon isotope composition of calcareous plankton at the Cretaceous/Tertiary boundary3, is the rapid global positive excursion of ~2 ‰ (13C enrichment) which took place between ~91.5 Myr and 90.3 Myr (late Cenomanian to earliest Turonian (C/T boundary event))1,4,5. This excursion has been attributed to a change in the isotope composition of the marine total dissolved carbon (TDC) reservoir resulting from an increase in rate of burial of 13C-depleted organic carbon, which coincided with a major global rise in sea level5 during the so-called C/T oceanic anoxic event (OAE)6. Here we present new data, from nine localities, which demonstrate that a positive excursion in the carbon isotope composition of organic carbon at or near the C/T boundary7,8 is nearly synchronous with that for carbonate and is widespread throughout the Tethys and Atlantic basins (Fig. 1), as well as in more high-latitude epicontinental seas. The postulated increase in the rate of burial of organic carbon may have had a significant effect on CO2 and O2 concentrations in the oceans and atmosphere, and consequent effects on global climate and sedimentary facies.

Description: Hurricanes and other strong storms can cause important decreases in sea surface temperature by means of vertical mixing within the upper ocean, and by air–sea heat exchange. Here we use satellite-derived infrared images of the western North Atlantic to study sea surface cooling caused by hurricane Gloria (1985). Significant regional variations in sea surface cooling are well correlated with hydrographic conditions. The greatest cooling (up to 5°C) occurred in slope waters north of the Gulf Stream where the seasonal thermocline is shallowest and most compressed; moderate cooling (up to 3 °C) occurred in the open Sargasso Sea where the thermocline is deeper and more diffused; little or no cooling occurred in shallow coastal waters (bottom depth less than 20 m) which were isothermal before the passage of hurricane Gloria. There is a pronounced right-side asymmetry of sea surface cooling with stronger (by a factor of 4) and more extensive (by a factor of 3) cooling found on the right side of the hurricane track. These qualitative results are consistent with the notion that vertical mixing within the upper ocean is the dominant sea surface cooling mechanism of hurricanes.

Description: There is now clear evidence that changes in the Earth's climate may be sudden rather than gradual. It is time to put research into the build-up of carbon dioxide in the atmosphere on a better footing.

Description: One of the most striking features of the upper North Atlantic Ocean is an extensive layer of water with temperature close to 18°C and salinity close to 36.5‰, (ref. 1). This 18°C water is formed by winter convection in the Sargasso sea2,3, but aspects of the annual rate of 18°C water formation remain obscure4. We have simulated this water mass formation by integrating a one-dimensional model along a 4-yr trajectory of a water column circulating around the Sargasso Sea. Winter convection is deep (≥200 m) in regions where the ocean suffers a net annual heat loss to the atmosphere, and shallow (≤lOOm) where the ocean gains heat each year. The origin of the thermostad (nearly isothermal layer) is a thick layer of nearly homogeneous water subducted beneath the seasonal boundary layer in the year that the water column passes through the line dividing annual cooling from annual heating. We estimate the annual production of 18°C water to be 446,000 km3 yr−1. Downstream, more stratified central water is formed each year at a rate that depends more on Ekman pumping (wind-forced convergence) than on the decreasing depth of winter convection

Description: To reconstruct the deep-water circulation for the last 3.5 Ma from deep-sea sediments of the eastern equatorial Atlantic, sea floor morphology, sub-bottom reflectors and the echo character have been mapped on the basis of 3.5 kHz records and sediment cores. Physical properties of sediments and synthetic seismograms derived from them enable us to decipher reflector sequences in environments of pelagic, currentresuspended and turbidity sedimentation. The individual reflectors originate from carbonate dissolution, hiatuses, coarse sand layers and interferences. Those which are related to carbonate dissolution and hiatuses provide evidence of water-mass boundaries by their distribution. Five phases of different deep-water circulation can be seen in the record of the last 3.5 Ma, and these are related to climate history: 1. Between 3.7 Ma and 2.2 Ma a strong deep-water circulation indicates a northward flow of bottom water below 4200 m (AABW = Antarctic - Bottom Water) and a southward flow of deep-water above 4200 m (NADW = North-Atlantic Deep Water). 2. Between 1.6 and 1.4 Ma a southward flow of bottom water below 4500 m and a diminished southward flow above 4500 m can be detected. This water-mass geometry can be interpreted by an expansion of the NADW-masses and a displacement of the AABW-masses during the same time. 3. Since 1.4 Ma a northward flow of a bottom-water current developed again. This current flow created a leeside sediment ridge in the southern part of the Kane Gap and furrows in the northern part of it. 4. Beetween 400,000 and 200,000 yrs B. P. the oceanic and atmospheric circulation increased. The strengthened oceanic circulation caused an increase in carbonate dissolution, which is documented by a traceable reflector from 2800 m to 4500 m water depth. At the same time an increase of the atmospheric circulation caused a drastic rise in the pelagic sediment accumulation (〉 100%) through an intensification of upwelling. This runs parallel with a higher oceanic productivity in the northern equatorial divergence zone and an enhanced supply of fluvial and probably eolian sediments from Senegal and Guinea. 5. Before 10,000 yrs B.P. an erosive northward flowing bottom-water current prevailed below 4500 m water depth. After 10,000 yrs B.P. the bottom-water flow was sluggish and non erosive.

Description: Based on the faunal record of planktonic foraminifers in three long gravity sediment cores from the eastern equatorial Atlantic, the sea-surface temperature history over the last 750,000 years was studied at a resolution of 3,000 to 10,000 years. Detailed oxygen-isotope and paleomagnetic stratigraphy helped to identify the following major faunal events: Globorotaloides hexagonus and Globorotalia tumida flexuosa became extinct in the eastern tropical Atlantic at the isotope stage 4/5 boundary, now dated at 68,000 years B.P. The persistent occurrence of the pink variety of Globigerinoides ntber started during the late stage 12 at 410,000 years B.P. CARTUNE-age. This datum may provide an easily detectible fauna! stratigraphic marker for the mid-Brunhes Chron. The updated scheme of the Ericson zones helped the recognition of a hiatus at the northwestern slope of the Sierra Leone Basin covering oxygen-isotope stages 10 to 12. Classifying the planktonic foraminifer counts into six faunal assemblages, according to the factor analysis derived model of PFLAUMANN (1985), the tropical and the tropical-upwelling communities account for 57% at Site 16415, and 86% at Site 13519, respectively of the variance of the faunal record. A largely continuous paleotemperature record for both winter and summer seasons was obtained from the top of the Sierra Leone Rise with the winter temperatures ranging between 20 and 25° C, and the summer ones between 24 and 30° C. The record of cores from greater water depths is frequently interrupted by samples with no-analogue faun al communities and/or poor preservation. Based on the seasonality signal, during cold periods the thermal equator shifted to a geographically more asymmetrical northern position. Dissolution altering the faunal communities becomes stronger with greater water depth, the estimated mean minimum loss of specimens increases from 70% to 80% between 2,860 and 3,850 m water depth although some species will be more susceptible than others. Enhanced dissolution occurred during stage 4 but also during cold phases in the warm stages 7 and 9. Correlations between the Foraminiferal Dissolution Index and the estimated sea-surface temperatures are insignificant. Foraminiferal flux rates, negatively correlated to the flux rates of organic carbon and of diatoms, may be a result of enhanced dissolution during cold stages, destroying still more of the faunal signal than indicated by the calculated minimum loss. The fluctuations of the oxygen-isotope curves and the hibernal sea-surface temperatures are fairly coherent. During warm oxygen-isotope stages the temperature maxima lag often by 5 to 15 ka behind the respective isotope minima. during cold stages, sea-surface temperature changes are partly out of phase and contain additional fluctuations.

Description: Over 100 samples of recent surface sediments from the bottom of the Atlantic Ocean offshore of NW Africa between 34° and 6° N have been analysed palynologically. The objective of this study was to reveal the relation between source areas, transport systems, and resulting distribution patterns of pollen and spores in marine sediments off NW Africa, in order to lay a sound foundation for the interpretation of pollen records of marine cores from this area. The clear zonation of the NW-African vegetation (due to the distinct climatic gradient) is helpful in determining main source areas, and the presence of some major wind belts facilitates the registration of the average course of wind trajectories. The present circulation pattern is driven by the intertropical front (ITCZ) which shifts over the continent between c. 22° N (summer position) and c. 4° N (winter position) in the course of the year. Determination of the period of main pollen release and the average atmospheric circulation pattern effective at that time of the year is of prime importance. The distribution patterns in recent marine sediments of pollen of a series of genera and families appear to record climatological/ecological variables, such as the trajectory of the NE trade, January trades, African Easterly Jet (Saharan Air Layer), the northernmost and southernmost positions of the intertropical convergence zone, and the extent and latitudinal situation of the NW-African vegetation belts. Pollen analysis of a series of dated deep-sea cores taken between c. 35° N and the equator off NW Africa enable the construction of palaeo-distribution maps for time slices of the past, forming a register of palaeoclimatological/palaeoecological information.

Description: Molybdenum and vanadium were analysed in 9 sediment cores recovered from the continental slope and rise off NW Africa. additional chemical and sedimentological parameters as well as isotope stage boundaries were available for the same core profiles from other investigations. Molybdenum, ranging between 〈 1 and 10 ppm, occurs in two associations, either with organic carbon and sulphides in sediments with reducing conditions or with Mn oxides in oxidized near-surface core sections. Highest values (between 4 and 10 ppm Mo) are found in sulphide-rich core sections deposited during glacial times in a core from 200 m water depth. The possibility of anoxic near-bottom water conditions prevailing at this site during certain glacial intervals is discussed. In oxidized near-surface core sections, the diagenetic mobility of Mo becomes evident from strong Mo enrichment together with Mn oxides (values up to 4 ppm Mo). This enrichment is probably due to coprecipitation and/or adsorption of Mo from interstitial water to the diagenetically forming Mn oxides. The close relation between Mo and Corg results in strongly covarying sedimentation rates in both components reaching up to 10 times the rates in glacial compared to interglacial core sections. Vanadium (values between 20 and 100 ppm) does not show clear relations to climate and near-bottom or sediment milieu. It occurs mainly bound to the fine grained terrigenous fraction, associated with aluminium silicates (clay minerals) and iron oxides. Additionally positive covariation of vanadium with phosphorus in most core profiles suggest that some V may be bound to phosphates.

Description: A statistical analysis of 15 deep sea cores in the eastern North Atlantic off NW Africa revealed the typical fluctuation pattern of distinct species groups as has been described from various parts of the world ocean. Only the "WBF-group" appears to be correlated with global climatic changes, i.e. warmer periods as the Eemian and the Atlanticum. A partly antagonistic "High Productivity group" (HPR-group) is in general not linked with global changes but times of increased fertility in the surface water and the resulting flux of organic matter reaching the bottom. The groups were extracted from cluster analysis of more than 150 surface samples (HPR-group, LuTZE & CouLBOURN 1984) and a factor analysis of selected cores (WBF-group). In contrast to previous studies the observed fluctuations can not be explained by drastic changes in bottom water masses, but by the pulsation of a distinct "High Productivity Patch" in space and time. At present, this patch is located below the well known upwelling area between 22° and 12° northern latitude. It shifted to the north (up to 27° N) during the latest glacial period (18 ky), indicating an equivalent shift of upwelling productivity caused by advection of nutrient rich upwelling SACW-waters, probably during most of isotopic stages 2 and 3.

Description: Marine organic carbon is heavier isotopically (13C enriched) than most land-plant or terrestrial organic C1. Accordingly, δ 13C values of organic C in modern marine sediments are routinely interpreted in terms of the relative proportions of marine and terrestrial sources of the preserved organic matter2,3. When independent geochemical techniques are used to evaluate the source of organic matter in Cretaceous or older rocks, those rocks containing mostly marine organic C are found typically to have lighter (more-negative) δ 13C values than rocks containing mostly terrestrial organic C. Here we conclude that marine photosynthesis in mid-Cretaceous and earlier oceans generally resulted in a greater fractionation of C isotopes and produced organic C having lighter δ 13C values. Modern marine photosynthesis may be occurring under unusual geological conditions (higher oceanic primary production rates, lower P CO2) that limit dissolved CO2 availability and minimize carbon isotope fractionation4.

Description: The climate record obtained from two long Greenland ice cores reveals several brief climate oscillations during glacial time. The most recent of these oscillations, also found in continental pollen records, has greatest impact in the area under the meteorological influence of the northern Atlantic, but none in the United States. This suggests that these oscillations are caused by fluctuations in the formation rate of deep water in the northern Atlantic. As the present production of deep water in this area is driven by an excess of evaporation over precipitation and continental runoff, atmospheric water transport may be an important element in climate change. Changes in the production rate of deep water in this sector of the ocean may push the climate system from one quasi-stable mode of operation to another.

Description: A considerable number of samples recently obtained from the collections of the German research vessels "Meteor" and "Valdivia" in the eastern North Atlantic have been evaluated for their planktonic foraminiferal composition. The new data enabled a quantitative and qualitative improvement of the data base for a statistical analysis of planktonic foraminiferal fauna using the transfer function technique of IMBRIE & KIPP (1971). 134 modern sediment samples from the eastern North Atlantic were selected according to their excellent preservation of foraminifera and treated by a principle component analysis. The resultant six factors account for 96.7% of the variance of the original data comprising 15 major species and species groups. A multiple regression analysis between these factors and the actual mean sea-surface temperatures and salinities resulted in a set of equations. They can be applied for estimating past sea-surface winter and summer temperatures and salinities from planktonic foraminiferal assemblages for approximately the last 500,000 years. The new functions have a standard error of 1.2° C for winter and summer temperature and 0.4‰ for annual salinity.

Description: Sedimentological and geotechnical analyses were carried out on two undisturbed large diameter deep sea cores from the Antarctic sector of the Atlantic ocean. One core, from a silled basin within the Bransfield Strait is characterized by fine grained hemipelagic material and turbidite layers. The other core, from the continental slope of the Weddell Sea represents a typical glacial marine environment. The variations of physical properties as related to both an increasing overburden pressure (or depth below top of core) and/or to lithological changes are discussed. With increasing overburden pressure only small variations of physical properties were observed. In core 14882-2 the porosity decreases 0.7% per meter, the natural water content 6% per meter. The wet bulk density and the shear strength increase with rates of 0.015 g/cm3 and 0.5 KPa per meter. Compared to small variations in consolidation, the changes of the lithology cause more extreme variations of physical properties: e.g. decreases the natural water content by 100%, the porosity by 14%, and the wet bulk density increases by 0.23 g/cm3 due to a turbidite layer in the core from the Bransfield Strait (core 14882-2). In the core from the continental slope of the Weddell Sea (core 14875-1) two major unconformities have been detected. The ice-rafted debris of this core causes a generally lower porosity (64%), a lower natural water content (75%), a higher wet bulk density (1.55 g/cm3) and specific grain density (2.62 g/cm3), compared to the core from the Bransfield Strait (porosity 77% , natural water content 151% , wet bulk density 1.34 g/cm3, specific grain density 2.47 g/cm3).

Description: The "Meteor" cores 22M36 and 22M37 are situated on the eastern rim of the Mediterranean Ridge SW of the Peloponnesus at 3200 and 3350 m water depth. Core 22M37 contains a breccia consisting mainly of Upper Serravallian/Lower Tortonian claystone clasts. They are characterized by smectite-dominated clay mineral assemblages. The breccia contains displaced benthic foraminifers of neritic character and bryozoan debris. At the top of the breccia follows a chaotic stratigraphic sequence including Serravallian (?), Tortonian, Messinian, Pliocene and Pleistocene sediments. The deposits of Upper Tortonian to Pleistocene age are characterized by illite-dominated clay mineral assemblages. The smectite-dominated assemblages are very similar to that of the surface sediments from the extreme eastern part of the Levantine Basin which represent Nile-derived terrigenous material. It is speculated, that during Upper Serravallian/Lower Tortonian time mineral detritus derived from an early "Nile" may have been transported into the Ionian Sea. This would implicite a seafloor morphology different from today's (the Mediterranean Ridge prevents sediment transport into the Ionian Sea) and considerable tectonic movements since that time. The termination of the smectitedominated sedimentation in the considered area SW of the Peloponnesus would indicate the beginning of the barrier function of the Mediterranean Ridge. Such movements have to be inferred also from the neritic components of the breccia. They have to be explained by turbiditic influx. However, in the present morphology, turbidity currents starting from a shallow water region could not reach the core positions. Core 22M36, situated close to core 22M37, represents a Quaternary sequence (upper part of nannoplankton zone NN 19 to base of NN 21) with conglomeratic layers and unconformities. They point to tectonic movements within this time. The origin of the breccia as well as of the chaotic sequence in core 22M37 may have happened near the boundary of nannoplankton zones NN 19/20.

Description: Hydrographie data (salinity, temperature, oxygen, silicate, and phosphate) obtained on 5 stations ("Meteor" cruise 23, leg C, 8 to 26 June 1971) on a section from Lisbon, Portugal, to 44° N, 43° W (Newfoundland Basin) by both water sampling and in situ observation by the "Bathysonde" (STD), are summarized. A strong core of Mediterranean water was found at the eastern boundary of the section (38.5° N, 11.5° W). At this station, the core is accompanied by low nutrient concentrations and brings about an extended oxygen minimum (ca. 500 to 1400 m depth). The core quickly weakens towards the west and is, at the Mid-Atlantic Ridge, only apparent in the Bathysonde data. Two salinity maxima are observed within the core of Mediterranean water, the center of which speads along the isopycnal σt = 27.7. Dissolved oxygen shows a rapid concentration increase with depth below the Mediterranean water core; concentration variations with depth below the range of this increase are only small. The mean deep-water oxygen concentration increases from 5.5 ml/kg (below 2500 m) to 6.20 ml/kg (below 1500 m) in an east-west direction on the section. The upper boundary of the deep-water oxygen concentration range thereby rises from 2000 to 1300 m; this boundary marks the upper boundary of the Arctic Intermediate water. Core depths of Arctic Intermediate and of Iceland-Scotland overflow water, are derived from the potential-temperature/salinity diagrams obtained in the western basin, and are extended to the other stations by assuming lateral spreading to occur along isopycnal surfaces. The core depths for the Intermediate water obtained in this manner, are supported also by the potential-temperature to silicate relations. The bottom water of the westernmost station of the section, at 44° N, 43° W, is of Denmark Strait origin, and it produces a distinct reversal in the vertical trends of salinity, silicate, phosphate, and oxygen, at 4300 m depth. The concentration of the nuclear-weapon produced nuclide tritium increases within the Denmark Strait water core towards the bottom. Further tritium concentration peaks appear in the intermediate and deep water at this station. At the next Station east on the section at 43° N 34 ° W, tritium concentrations are essetially zero below 2000 m depth, and are distinctly smaller than on the westernmost station, between 600 m and 2000 m depth. This "Meteor" section was track F of the Atlantic network of the international Geochemical Ocean Sections Program (GEOSECS).

Description: At seven sites west of Gibraltar current and temperature variations of the Mediterranean outflow were observed during one month in spring 1971. This paper presents the obtained records of 29 current meters and 5 thermistor cables in the form of time series, amplitude spectra, and progressive vector diagrams as a basis for further evaluation. Characteristic featurcs of the currents like mean spceds, mean directions and the periodicity of the variation can be seen directly from the given plots.

Description: During the Northeast-Atlantic-Expedition of 1971, C02 concentration in the air layer near the ocean surface and C02 partial pressure in the surface water was measured between Lisbon and Weather Ship D as well as between Weather Ship D and Hamburg. These measurements were supplemented by depth profiles of C02 partial pressure in the ocean. The resulting zonal distribution is discussed. An interesting aspect of the C02 concentration values in the air layer above the ocean is their significant correlation with the temperature difference between air and water. The possible meaning of this correlation with the regard to the exchange of C02 between ocean and atmosphere is demonstrated by estimating the C02 flux for a particular case. The annual variation of C02 partial pressure in surface water is discussed for two points on longitude 30° W at which the route of the 1971 expedition intersects the route of the 1969 expedition. It is deduced that in temperate latitudes the annual variation of C02 partial pressure in surface water is related to that of surface-water temperature. Based on this relationship and on the PC02 decrease of 35 ppm measured between April and June it is estimated that the annual variation of C02 partial pressure in surface water for the oceanic area around 50° N 30° W amounts to 60 ppm ± 15 ppm.

Description: The diurnal variation in the concentration of C02 in the air and in the water near the ocean surface has been measured during the Atlantic Expedition of 1969. While at the Drift Station in the NE-trade wind belt, a mid-day minimum in the diurnal variation of C02 in the atmosphere was found similar to that measured by Kumvrn (1968) 1965 in the SE-trade wind belt. At the Equator Station under the influence of the intertropical convergence zone, on the other hand, a mid-day maximum was found. Statistical correlations between the C02 concentrations and various meteorological parameters could not be used to reveal the origin of such differing diurnal variations. By using a simple computer model it appears that a diurnal trend to the intensity of oceanic sources of C02 may be responsible for the diurnal variation of C02 in the atmosphere. Since the variations in the concentration of C02 in the near-surface waters were found to be too small to explain the variations observed in the atmosphere, other processes were discussed which lead to a stronger variation of C02 concentration in the laminar boundary film of the ocean surface. Since the C02 system in sea water is a function of both the temperature and the salinity, the concentration of C02 in the boundary film may be strongly influenced by the fluxes of radiation and evaporation. The diurnal variations found at the Equator Station can then be explained primarily through the variations in the temperature of the boundary film. At the Drift Station, however, an enrichment of salt content in this film through a greater evaporation rate may be the basis for the variations of C02 there. Such deviations in the concentrations of C02 between the laminar surface film and the near-surface waters seem important to the exchange of C02 across the sea-air interface.

Description: To estimate the disturbing influence of a ship's hull and superstructure on measurements of wind speed, air temperature and humidity and surface water temperature, data taken from R.V. "Meteor" are compared with simultaneous measurements from a meteorological buoy. It is shown that almost no systematic errors occur in the measurement of water temperature while the wet bulb temperature is generally indicated to high by 0.1°C to 0.2°C. However, due to large heating of the ship's body during daytime, a systematic increase of dry-bulb temperature is observed which also leads to erroneous values of relative humidity. During nighttime, the errors in dry-bulb temperature remain small. Wind-speed measurements, in particular, are critical from board a ship. The "Meteor" data show that the ship's values are systematically smaller than the measurements at the buoy, the difference increases with increasing wind speed. Although WARSH et al. (1972) found the same behaviour with R. V. "Discoverer", the result cannot be generalized, and similar investigation are recommended for any ship the data of which will be used for more extended evaluations. The errors are examined concerning their influence on the computation of turbulent heat fluxes from the bulk-aerodynamic equation. The result shows that, even if the diurnal march of dry-bulb temperature is corrected, the fluxes are still erroneous due to the wind-speed error. The conclusion, therefore, is that data taken from a ship are in general inappropriate for the more detailed investigation of surface-energy fluxes, unless a good correction function for all the parameters involved is known.

Description: Aerosol samples collected over the North Atlantic from ship were analysed for Sodium, Magnesium, Potassium, Calcium and Chloride. A found dependence of sea salt concentrations from wind velocity is compared with earlier results. The mean of the ratio Cl/Na was close to that for sea water; the Mg-, K- and Ca-concentrations in the aerosol, however, were enriched with respect to sea water. It is shown that continental advection influences the measured aerosol components over the North Atlantic.

Description: Satellite pictures and the results of radiosonde ascents indicate that FS "Meteor" was placed very near to or within the region of the ITCZ during the anchor station 1969 (March 8 to April 4) at the equator in 32° W. In spite of this the most frequently observed radar echoes are smaller than 100 km2, which is also shown by the small radar index (mean value 2.6%). The diurnal variation of the radar index over the ocean shows two maxima, in contrast to the continental typ. There is a weak maximum in the late afternoon due to surface heating. But the main peak occurs in the early morning (3 a.m. local time), apparently due to the increasing instability in the lower troposphere by longwave outgoing radiation. A frequently (20%) observed phenomenon is the arrangement of the echoes in organized structures, four examples of which are discussed: convergence line, shower streets, open cells.

Description: During cruises in the Norwegian Sea in 1969 and 1972 seven heat flow values were measured between Iceland and the Vøring Plateau. The six eastern values of this profile show a positive trend eastsoutheastwards which coincides with a possible transition from oceanic to continental ernst suggested by seismic results. One heat flow value taken near Iceland and 250 miles west of the others reflects the influence of the Mid-Atlantic Ridge. An estimation of the heat flow at a depth of 15 km below the measuring localities yields values with a small, possibly insignificant negative trend towards the east-southeast. The temperatures at 15 km depth are estimated to be 190°C beneath the zone of seamounts and 280 °C beneath the Vøring Plateau.

Description: The continental margin off West Africa between 22° and 27° N has not developed by simple progradation and continuous sedimentation. Two unconformities which can be followed over large distances and drillings both on land and at sea suggest that a pre-Oligocene shelf has subsided there by more than 2000 m caused by orogenic movements south of the Atlas region. The former shelf edge is marked today by a slope anticline. We prefer this regional explanation and not a global one combining the huge hiatuses in the sediment column underneath the present continental slope and rise with a dramatically stronger occanic circulation at the Paleogene/Neogene boundary. The subsided shelf sediments, the slope anticline and the unconformities are of specific interest for oil exploration.

Description: 1. ATP in deep-sea sediments can be determined after it is adsorbed on a mixture of the sediment and calcium carbonate by measuring the luminescence of the reaction of the mixture and luciferin-luciferase. 2. ATP contents of the toplayer of northeastern Atlantic sediments (Josephine Bank and northern Canary Basin) decrease with increasing depths of 252, 408, 1445, 1769, 2149, 4897, 5510 m: 0.96, 0.61, 0.13, 0.10, 0.21, 0.05, 0.07 μg ATP/ml wet sediment. The decreasing values are in accordance with the decrease of macrobenthos and meiobenthos biomass in the deep-sea. 3. The ATP content of deep-sea nematodes is about 1‰ of their wet weight. 4. At the two deepest Stations, less than 50% of the ATP measured in the sediment is represented by nematodes, copepods, other "hard" meiofauna groups and bacteria.

Description: In an area regarded to be very favourable for the study of Holocene sea level changes one or several eustatic (?) oscillations of sea have been found using sedimentological and ecological methods. After a maximum of +3 m during the Nouakchottian stage (= Middle Flandrian or Late Atlantic) about 5500 YBP a drop of sea to -3.5 ± 0.5 m about 4100 YBP is testified by stromatolitic algae indicating the former sea level within the tidal zone with high accuracy. This evidence is supported by the observation of post-Nouakchottian regressive and transgressive geologic sequences, by buried beach deposits and flooded hardgrounds, post-Nouakchottian marine terraces of different height and age, the cutting off of one large and several small bays from the open sea etc. Possibly, one or two smaller oscillations followed between 4000 and 1500 years B.P. (derived sea level curve Fig. 5). The radiocarbon age of the marine shells dated may be partly somewhat too old or too young (Chapter G, Table 1).

Description: During "Meteor"cruise 1965 the author collected 134 samples of surface sediments from the Iranian part of the Persian Gulf. Benthic Foraminifera populations have been analysed for determining their depth zonation. These data are supposed to allow detailed depth interpretation of pleistocene sediments found in cores. In addition, the ecological information might be usefull to reconstruct the depositional environment of fossil sediments in similar shallow epicontinental seas. The investigation is published in two parts: the present part 1 contains the catalogue of species with short discussions of taxonomic problems, notes on the distribution within the Persian Gulf and 11 plates, partly with scanning electron micrographs. The results of the statistical analysis are given in data tables which include number of species, percentages of 2 (and 5) ranked species, standing crop and foraminiferal numbers. The author used "species groups" to avoid ambiguities with species requiring additional taxonomic studies. However, species numbers within these units are estimated to yield applicable diversity information. - A total of 52 species and 7 "species groups" were separated, 2 new species were described. Complete series of reference material were deposited in the British Museum (N.H.), London and the U.S. National Museum, Washington (BMNH 1973: 10: 22: 1 172 and USNM 36/203331 - 203383). Part 2 (ecological part) is in preparation and is supposed to contain diagrams showing depth distribution, relation of fauna with grain size of sediments, distribution maps and the ecological interpretation of dominant distribution patterns.

Description: From the south-eastern Tyrrhenian deep-sea floor, four sediment cores of "Meteor" cruise 22 (1971) are described. These cores were taken in the basin between the Aeolian Islands and the Marsili Seamount, an elevation of more than 3000 m above the sea floor. The sedimentation of the deep-sea basin is distinguished by a sequence of turbidites with a high sedimentation rate. The composition of the clastic material and the position of the cores in the mouth area of the morphologically very pronounced Stromboli Canyon suggest an interpretation of the turbidite sequence as fan of this canyon onto the deep-sea floor. A white rhyolitic pumice-tephra at the base of the 4 m thick sequence of turbidites in core M 22-102 has been correlated with the Pelato eruption of the island of Lipari in the 6th century A.D. At the foot of the Marsili Seamount - apparently in morphologically elevated positions - the influence of the turbidite sedimentation decreases, the rate of sedimentation is lower and stratigraphic omissions are probable. Here, rather compacted globigerina marls have been found in only 15-25 cm depth. In addition, volcanic material in the form of lapilli layers, palagonitized ashes and detrital volcanic sands of the Marsili Seamount have been encountered in this area. An up to 3 cm thick layer of completely palagonitized basaltic ash intercalates with the marls at the base of two cores. Layers of very fresh olivine basaltic lapilli in core 103 and palagonitized lapilli of latitic composition in core 104 testify to an explosive submarine volcanism of the Marsili Seamount. According to the stratigraphy of core 103, the latest manifestations of this basaltic volcanism belong to the late Pleistocene (Emiliana huxleyi-zone of Nannoplankton stratigraphy). The basaltic lapilli are glassy to perhyaline with phenocrysts or microphenocrysts predominantely of olivine. The petrological character of the basaltic volcanites with high MgO, Ni, Cr and high MgO/FeO- and Ni/Co-ratios exhibits primitive basaltic features. These basalts clearly differ from basalts of the ocean floors, mid-ocean ridges and marginal basins. Prominent features are a missing ironenrichment trend and low Ti02. Al203 tends to be high, as well as K20 and related trace elements (Ba, Sr). In spite of silica undersaturation and high color index, the Marsili basalts exhibit some analogies with the calcalkaline basalts of the Aeolian arc, as well as with the undersaturated basalts of some other circumoceanic areas.

Description: Chemical analyses have been carried out on 40 samples from the sediment surface and 210 samples from cores that were taken from the edge of the African continental block at the Arabian Sea (coasts of Somalia and Kenya, from Cape Guardafui to Mombasa) on the occasion of the Indian Ocean Expedition of the German research vessel "Meteor" during the years 1964/65. The carbonate content shows its maximum on the northern part of the continental shelf of Africa, where fossil reef debris furnish the detritic portion of carbonate. In the southern part of the continental shelf of Africa the portion of carbonate is low, as it is heavily diluted by the non-carbonatic detritus. lt is also in the deep-sea that a lower carbonate content is encountered below the calcite compensation depth. Trace elements in the carbonates: On the shelf and in its vicinity Sr and Mg are enriched. The enrichment has been brought about by the portion of reef debris, as this latter contains aragonite (enrichment of Sr) as well as high-magnesium calcite. The greatest patt of the slope contains carbonates that are poor in trace elements and mainly made up of foraminifera (and of coccoliths). Below the carbonate compensation depth another enrichment of Mg takes place in the carbonates, which is probably due to a selective dissolution of calcite in comparison to dolomite. The iron and manganese contents of the carbonates are high (iron higher in coast proximity, manganese higher in the depth), but not genuine, as they come about in the course of the extraction of the carbonates as a result of the dissolution of authigenic Mn-Fe-minerals. Non-carbonatic portion of the sediments: In coast proximity an enrichment of quartz comes about. Within the quartz-rich zone it is the elements V, Cr, Fe, Ti, and B that have been enriched in the non-carbonatic components. This enrichment must be attributed to an elevated content of heavy minerals. In the case of Ti and Fe the preliminary enrichment brought about by processes of lateritisation on the continent plays a certain role. Toward the deep-sea an enrichment of the elements Mn Ni, Cu, and Zn takes place; these enrichments must be explained by authigenic Mn-Fe-minerals. Within the Mn-rich zone a belt running parallel to the coast stands out that shows an increased Mn-enrichment. However, this increase in enrichment does not apply to the elements Ni, Cu, and Zn. lt is probable that this latter increased enrichment comes about as a result of the migration of manganese to the sediment surface. (Within the sediments there prevail reductive conditions, in the presence of which Mn is capable of migration, whereas at the sediment surface its precipitation comes about under oxidizing conditions). The quantity of organic matter mainly is dependent on grain size and on the rate of sedimentation. On the shelf an inpoverishment of organic matter is to be encountered, as the sediments are coarse-grained. In the depth the impoverishment must be explained on the strength of a small rate of sedimentation. Between those two ranges organic substance is enriched. P and N show an enrichment in comparison to Corg. with this applying all the more the smaller the absolute quantity of Corg. is. In this particular case one has to do with an enrichment coming about during the diagenetic processes of organic matter. A comparison with the sediments from the Indian and Pakistani continental border in Arabian Sea shows as follows: on the African continental border the coarse detrital material has been transported farther out to deep-sea, which has something to do with the greater inclination of the surface of sedimentation. Carbonate is found in greater abundance on the African side. Its chemical composition is influenced by reef-debris which is missing by Indian-Pakistani side. The content of organic matter is lower on the African side. Contrary to that, the enrichments of N and P compared to organic matter are of an equal order of magnitude on both sides of the Arabian Sea.

Description: 85 subsamples with coelenterates collected during the "Meteor"-Expedition into the Arabian Sea and sorted out in Kiel were checked for hydromedusae. Furthermore ten samples from the southern entrance of the Red Sea and 29 samples from the "John-Murray"-Expedition into the Indian Ocean (1933/34) which were stored at the British Museum (Nat. Hist.) are considered in this paper. In all this material 47 species of hydromedusae were found. Most of them are rather common in the Indian Ocean, only Phialidinum lomae and Aglantha intermedia are new to this sea. Velella velella, Oceania armata, Köllikerina omata, Phialidinum lomae and Eucheilota tropica are recorded from the Red Sea for the first time. Between the material of the "Meteor"-Expedition and the "John-Murray"-Expedition no fundamental difference appeared. The southequatorial current system seems to be richer in species than the northern systems. Off the Indian coast a relatively high number of species was found. 3089 specimen were counted in the Material of the "Meteor"-Expedition into the Arabian Sea. Aglaura hemistoma (60%), Solmundella bitentaculata (13%) and Liriope tetraphylla (12%) account for 85% of the individuals. No significant correlation seems to exist between the numbers of specimen in different regions and biotic and/or abiotic factors.

Description: The present study deals with 3 new genera and 14 new species of the Copepoda Harpacticoidea from the Peru-Trench and the Iberian deep-sea. The systematical position of the Argestigensgroup (Cletodidae) is discussed within the taxonomical remarks concerning the genus Parameiropsis n. gen.

Description: Description of Trefusialaimus monorchis nov. gen. nov. spec., Trefusiidae, characterized by only one testis, by seminal duct without differentiation of a muscular ductus ejaculatorius, and by pericloacal papillae. Second species of genus is T. magnus (FILIPJEV 1946), syn. Trefusia magna. With particular reference to the male genital apparatus Trefusialmus combines features of Dorylaimida Alaimina and Enoplida Tripyloidea.

Description: During the Indian Ocean Expedition of R/V "Meteor" phytoplankton samples were taken with a multiple closing net ("multinet") at 103 stations. In this material the diatoms were investigated. In all 247 taxa could be identified which belong to 242 species and 5 varieties or formae of 80 genera. Of these 1 variety, 15 species, and 3 genera are newly described. New combinations were made for 18 species, and a number of old combinations was reinstated. A distribution list of all species in the investigated area is included.

Description: STEP-LIKE structures in temperature and salinity beneath the Mediterranean water have been observed in the Eastern Atlantic1–6. In Fig. 1 we show the stations where steps have been found in the area to the west of Gibraltar. Salt fingering as a result of double diffusive processes has been suggested as a possible cause for the generation of such step-like structures7. During cruise No. 23 of RV Meteor in 1971 we intended to study the small scale features of such structures8. Some previous observations6 in August/September 1970 had revealed an extensive zone where a “thermohaline staircase” existed (Fig. 1). We therefore selected stations in this area and close to it for the proposed study. A high resolution in situ conductivity-temperature-depth meter of the “Kieler Multi-Meeressonde” type was used for the vertical profiling of temperature and salinity.

Description: In July, August and September 1969 a joint German-Icelandic-Norwegian-Expedition investigated time- and space-dependent oceanographic processes in the Norwegian Sea (fig. 1) and in the waters east of theIcelandic Shelf as weil as the geological and geophysical structure of the Norwegian continental slope, the Norwegian Basin and the Jan-Mayen-Ridge. The participating research vessels were "Hafthor" from Iceland, "Helland-Hansen" from Norway, "Anton Dohrn" and "Planet" from the Federal Republic of Germany (FRG) and as shooting vessel "Nordkapp" from Norway. "Meteor" (FRG) was eliminated from the measuring programme because of engine trouble shortly before begin. Due to the prolonged activity of "Planet" the originally planned investigations were almost entirely able to be carried out. The measuring programme and the preliminary results of the geological and geophysical working groups are dealt with separately (Closs et al. 1972). Systematic sounding from "Planet" in the main working area between 62° and 63° N, and 3° 25' and 4° 50' E forms the basis for a special contour map (see supplement). As a result of improved mooring technique in the course of the expedition's oceanographic measuring programme an almost one hundred percental retrieval of instruments was achieved and herewith 49 current and 55 continuous temperature recordings over 12 to 45 days in depths between 10 and 800 m were obtained. Hydrographie sections, nine anchor- and driftstations as well as one in five days six times successively passed through triangular course gave information over stratification and its periodic changes. The distribution of stations and the position of the moored self-contained instruments in the main working area is found in figure 2. Figure 3 gives insight into the registration period and depth of the instruments of the by "Planet" in cross formation moored systems I to VI. Parallel to the work clone off Norway observations were made as to variability of physical and chemical parameters in east Iceland waters.

Description: At first a technique is presented to evaluate repeated hydrographic sections. In order to separate the periodic variations and the fluctuations which arise as a result of the horizontal motion of the profiling ship, the data at defined locations are averaged relative to time. The procedure of averaging can be applied successfully to sets of sections repeated at a constant rate under the assumption that the spatial field is approximately stationary during the time of observation and that the energy of the overlapping temporal processes is concentrated over a few spectral bands. In these cases, the mean spatial distribution can be expected as a result. The periodic part is extracted as the deviation of the actual sections from the averaged section. This procedure was applied to a set of observations made at 28 discrete stations along a triangular course at the continental shelf off the coast of Norway during the expedition "Norwegian Sea 1969". Temperature sections were repeated six times at an interval of 18 hours. The average section shows the expected downsloping of the isotherms perpendicular to the continental shelf corresponding to the Norwegian current. lt turns out that the fluctuations with respect to time during the period of observation are probably produced by semidiurnal internal tides. Wavelength and phase velocity are estimated to be A = 22 km and c = 0.5 ms-1 respectively. The waves progress towards the shelf at right angles. For depths of 250-500 m at the continental slope a considerable amplification of wave is noticed.

Description: The seaward extension and vertical structure of the Coastal Current have been studied, on the basis of a repeated hydrographic section across the Norwegian Shelf off Stad. Current measurements were obtained from five anchor stations. The current ellipses do not reveal a consistent picture of the tidal current system, indicating that the observed currents may be influenced by internal tidal waves.

Description: The N2O in air and sea water from the Iceland-Faroe ridge was analyzed during the research vessel "Meteor's" cruise 20b from May 30 to July 4, 1970. Depths of the water samples varied from surface to 1000 meters. An improved analytical method yielded an average value of 0.495 micrograms of atmospheric N2O per liter (STP) of air. A slight N2O supersaturation of the water samples with respect to air was demonstrated.

Description: A bottom water sampler ("Suctor") for application in the deep-sea, in shallow waters and in estuaries is described. It is operated by hanging it on a wire and placing it on the sea floor. After waiting for 5-20 min for allowing the stirred sediment to be removed, an electrical pump installed in the sampler is operated from board of the ship. The bottom water sampler then samples simultaneously a volume of 10 litres from each 8 depths between O and 200 cm above the bottom. The samples are sucked into plastic bags through silicon rubber tubes; both the bags and the tubes can be kept extremely clean. The samples can be stored on board in the bags or can be connected to a filtering apparatus. During operation the bottom water sampler is connected with the ship by a wire, a conductor cable and the signals of the pinger device. Hence, its operation can be controlled on board at any time. During "Meteor" expedition 23 (summer of 1971) the sampler was used successfully between Madeira and the Straits of Gibraltar. Currents of 0-2 cm/sec were observed during operation by use of a Richardson current meter operatecl 44 cm above the bottom. The compass data of the current meter prove that the bottom water sampler maintained rigid contact with the sea floor. Analysis of particular organic nitrogen did not reveal significant gradients within the first two metres above the bottom.

Description: Olive-gray mud covers the continental slope off southern Portugal; at the same time sandy, reddishbrown mud was deposited off Morocco. Biogenie carbonate is a main constituent in both sediment types, off Portugal contributing about 25% and off Morocco more than 50%. The sediment cores from the Portuguese and Moroccan continental slope can be correlated by sedimentological and micropaleontological methods (figs. 10, 15). The climatic variations during the late Pleistocene and Holocene are weil documented by the content of ice-rafted debris (figs. 8, 13) and by faunal compos1t1on of planktonic foraminifera (THIEDE 1971 ). Radiocarbon ages indicate that these variations coincide with variations in the climatic record of the Iberian Peninsula based on pollen analysis (fig. 33). The calculation of sedimentation rates allows an estimate of the amount of terrigenous supply and biogenic carbonate production during the last 15.000 years (table 5). Planctonic organisms produced about 400 gram pro 100 cm2 per 1.000 yrs, while the contribution of benthos is relatively low (2.5 gram). The sedimentation rate of planctonic foraminifera increases from the open ocean to the region of the upper continental slope (fig. 27). This trend, caused by the better food supply near the continental influx and upwelling area, appears both off Portugal and Morocco. The sedimentation rate of benthonic remains decreases by a factor of 100 from the upper continental slope to the deep-sea plain (fig. 28). lt can be shown that this decrease is caused mainly by the reduction of available food with increasing water depth (figs. 29, and 30). In contrast to the biogenic sediment supply, which off Portugal and Morocco is not quantitatively different, the terrigenous supply from the weakly humid Iberian Peninsula is 3-4 times greater than the supply from the semiarid Moroccan mainland (fig. 31 ). This difference influences diagenetic processes. Small manganese concretions and reddish staining iron oxides, which remain stable under the oxygenated conditions in the sediments off Morocco, were replaced by pyrite during the destruction of organic matter in the sediments off Portugal through anaero bic bacteria. During the late Pleistocene a maximum of terrigenous and biogenic sediment (fig. 33) was deposited together with additional, mainly coarse sediment brought in by drifting icebergs. Mediterranean outflow water reduces the sedimentation of silt- and smaller sized particles on the Portuguese continental slope between water depths of 500 and 1.500 m. As a result this sediment is mainly deposited in water depths of 2.000 and 3.000 m (fig. 32). This form of sediment distribution and the high sedimentation rate of silt-sized particles under the southern part of the outflow water (core 8066 B) are characteristic of the time at least since the late Pleistocene. This would indicate that since then the outflow pattern of the Mediterranean water has not changed.

Description: Research cruise No. 4 of R.V. "Meteor" investigated the crest and upper flanks of the southern Reykjanes Ridge, in the region bounded by 52° 15' N, 56° 45' N, 33° W, and 37° W (fig. 1). Tracks spaced about 20 nm were laid out on a northsouth and east-west grid (fig. 3). The final smoothed track plot achieved acceptable relative accuracy, despite the poor navigational control. The median rift valley, not found on the Reykjanes Ridge north of 57.5° N, begins to be a well defined feature between 53.5° N and 54.5° N (figs. 2 and 6). In the survey area, free-air anomalies are entirely positive with a mean of + 60mgals. The anomaly pattern (fig. 7) mirrors sea-floor topography. A low ( 〈 + 40 mgals), associated with the rift valley, trends north along 35° 15' W from 53° 20' N to 54° 20' N. Less pronounced ( 〈 + 60 mgals) it can be followed as far north as 56.5° N. Some more transverse positive (〉 + 80 mgals) and negative ( 〈 + 50 mgals) free-air anomalies trend east between 54° N and 56° N and a parallel low ( 〈 ± 0 mgals) lies just to the south, coinciding with the Charlie Fracture Zone at 52° 45' N. In contrast to our results, TALWANI et al. (1971) found relatively positive zones of free-air anomalies over the ridge axis, and parallel to it, at a morphologically smoother part of the ridge, north of 59° N. The dependence between water depths and free-air anomalies yields an average of 2.3 g/cm3 without, and 2.6 g/cm-3 with topographic correction. This value as well as the positive free-air anomalies alone evidences a small amount of isostatic compensation. Bouguer anomalies have been calculated with three-dimensional topographic correction for standard density of 2.67 g/cm-3 (fig. 8) and for "true" density determined from rock samples of 2.90 g/cm-3 (fig. 9). In both cases, a slope of regional negative Bouguer values, centered on the ridge axis, points to a material in greater depths which is lighter than the normal mantle material ("root"). Similar gravimetric and seismic results, respectively, were obtained by M. TALWANI et al. (1965) south, and K. ARIC (1970 and 1972) north of the survey area. A thick layer of low density material under the axis (fig. 13) may be partially molten ultrabasics ascending into the rift axis as part of the sea-floor spreading process. The rift axis is characterized by magnetic anomalies of + 1000 to 1500 gamma amplitudes (figs. 10 and 11 ). A lineation pattern, symmetrical about the rift axis, is approximated by the model profiles computed from the standard HEIRTZLER reversal chronology and 1.12 cm/year spreading half-rate in the 095° T direction of relative motion between the Europe and Americas plates (fig. 14). The same rate, within measurement error, was found by HEIRTZLER et al. (1968) on the northern pare of the Reykjanes Ridge. The decay of anomaly amplitude away from the spreading axis suggests a 50 % reduction in magnetization intensity, or a similar reduction in thickness of the magnetized layer, in the first 5 my of crustal age. The former explanation is more probable; a similar decay is found elsewhere (VOGT et al. 1970). A significant finding is that the spreading axis as well as the anomaly pattern at least back to 5 mybp is not straight like the northern Reykjanes Ridge. In contrast to the physiographic interpretation of HEEZEN who shows transverse fractures perpendicular to and offsetting the rift valley, the axis is broken into oblique sections of the order 100 km long. Spreading rates normal to these sections range from 0.97 to 1.10 cm/year. The present irregular shape of the axis was formed in the late Tertiary, some time prior to 5 mybp but after 30 mybp. A similar irregular trend, discovered from detailed surveys between 48° and 50° N, was created about 20 mybp (JOHNSON & VOGT 1972).

Description: A coordinated geochemical and sedimentological study was made of recent marine sediments which were recovered during "Meteor" Project 22 (April 1971 ), in the vicinity of the Aeolian Islands. These unconsolidated clastic sediments, ranging from clay to gravel, are mostly composed of volcanogenic and pelagic detritus and, areally much more limited, contain crystalline debris derived from Sicily. According to composition, origin and mode of deposition, four sedimentary cnvironments were distinguished: the island flanks and the bay of Vulcano, the floor of the "Canyon di Stromboli", the eastern escarpment of this canyon, and the sea basin northwest of Stromboli. The importance of turbidite cycles, current-sorted horizons, or quietly sedimented pelagic clay, varies from one environment to another. Pyroclastic debris are found in all environments. The chemical analyses show that there are definite relationships between trace element concentrations and the sedimentary environments and, as to be expected, grain-size. Significantly higher copper concentrations are found closer to Vulcano than elsewhere, whereas the zinc content, because of its higher mobility, increases in deeper off-shore environments. Although the submarine fumaroles and thermal springs around Vulcano are known to be the source of metals, it should be emphasized that the predominance of coarse sediments and the absence of reducing conditions near these sources prevent any high concentrations from forming. The relatively turbulent environments, even at depths of over 3000 m (turbidite sequences), are also far from being conducive for metal enrichment.

Description: Morphology, distribution, and origin of the "cobblestones" in the Ionian Sea are discussed on the base of the results of bathymetric and seismic measurements, carried out by the R.V. "Meteor"

Description: During the cruises No. 17 and 22 of the German research vessel "Meteor", 45 water samples were taken at 4 stations in the central part of the Mediterranean Sea. Mass spectrometrical analyses showed that systematic, but time variable changes of the oxygen isotope ratios occur. Deep water samples (T 〉 500 m) have a ± constant isotopic composition of δ18O = + 1.79‰ (SMOW) and a chlorinity of 21.399‰. These data are discussed with respect to paleotemperature determinations.

Description: The portion of the continental shelf off Spanish Sahara lying between 23° 00' N and 22° 18' N is 80 km wide, flattens slightly between 40 and 60 m and breaks to the slope at 110 m. Over 200 nautical miles of side-scan sonar profiles were run in both reconnaissance and detail track configuration. Each survey covered a strip of the bottom ca. 280 m wide. A sediment distribution pattern which appeared to have complex lateral variation was revealed to be the result of a) "windows" in a thin, fine-grained upper sand layer exposing a coarse-grained sand below. In outline these windows run the full range from strongly parallel strips (width ca. 20 m) to irregularly bounded, somewhat elongate forms (width over 200 m). They all exhibit a preferred orientation parallel to the isobaths; b) Outcrops of probable semi-lithified and truncated Pleistocene sand dunes at depths between 30 and 80 m. Other outcrops are thought to belong to Pleistocene beachrock and pre-Pleistocene strata; c) Fields of the pelecypod Pinna ramulosa in water depths between 48 and 57 m with characteristic acoustic reflections; d) Largescale, wave-formed ripples as well as current-formed megaripples. The side-scan interpretation was corroborated through underwater TV observations, coring, samling, and air-gun profiling.

Description: Recent sediments off East Africa coast show 5 facies, parallel the coast: biogene carbonate sand, olivgrey mud, foraminiferal sand, globigerine ooze, and deep sea clay. These sediments decrease progressively in grain size, carbonate content and shell debris away from the coast. They differ in the primary and biogenetic structures, degree of bioturbation, lebensspuren and content of fecal pellets.

Description: Cores from the Atlantic Ibero-Moroccan continental rise and slope contain fine-grained Late Pleistocene and Holocene sediments. These young sediments cover the continental margin in large lensformed litho- and biostratigraphically well-defined units. The total sedimentation rates range from 4 cm/1000 yrs. to 27 cm/1000 yrs. off Portugal and from 6 cm/1000 yrs. to 14 cm/1000 yrs. off Morocco. Only a small proportion of these sediments usually consists of sand-sized particles (〉 0.063 mm) which are mostly dominated by foraminifera. Both planktonic and benthic foraminifera are much more abundant in Late Pleistocene and Holocene samples from the upper slope in comparison to those from the deeper slope and from the abyssal plains. Total sedimentation rates during cool and warm climatic stages are rather similar for both groups of foraminifera. For example, in Late Holocene sediments 7 X 103 benthic and 201 X 103 planktonic foraminifera (fraction 0.63-0.20 mm) per 100 cm 2 and 1000 yrs. are preserved in the Tagus, 10-19 x 103 benthic and about 1.3 X 106 planktonic foraminifera are preserved in the Seine abyssal plain sediments. Values from the upper slope sediments are higher for benthic foraminifera by a factor of 60 off Portugal and 60 to 70 off Morocco. The values for planktonic ones differ by factots of 6-12 and 6 respectively. These numbers seem to reflect differences in production and preservation. Production rates of planktonic foraminifera generally seem to be somewhat higher during Holocene than during Late Pleistocene, and the rates of benthic foraminifera appear rather higher during Late Pleistocene than during Holocene.

Description: In 9 samples from the Josephine Bank and Great Meteor Bank 23 halacarids were found among a macrofauna; mainly on hydroids and anthozoans. The 6 species found were Halacams actenos TROUESSART, Copidognathus tricomeata (LOHMANN), C. longipes n. sp., Agane alberti (TROUESSART), Aganopsis meteoris n. sp., and Lohmannella falcata (HODGE). Agane drygalski (LOHMANN) and A. bradypus NEWELL are considered to be synonyms of A. alberti. Copidognathus longipes and Aganopsis meteoris were not yet known. Copidognathus triconeata is new to the fauna of the North Atlantic. The most common species was Agane alberti; 11 individuals were found in 7 of the 9 samples.

Description: At a longtime station near the "Große Meteor Bank" in the North Atlantic 41 subsequent hauls were made in April 1967 with the Helgoland larva net with changing bucket device. In addition 9 hauls were made during July 1967. The catches from the depth ranges of 900-700 m, 700-500 m, 500-300 m, 300-200 m, 200-100 m, and 100-0 m were collected in separate buckets during each catch series. Contamination, though possible on principle, does not seem to be of much consequence in appendicularia. After some comments on certain species caught (part A, figs. 3-6, table 1, 2) it is shown that at this station in the open ocean the density of appendicularia not only varies with the season, but that clouds of plankton may pass by it within a few hours, in which the density may vary at a ratio of ten or more to one (B, fig. 7, table 7, 8). In the composition of species as many as four species may in turn be the most abundant (C, table 3, 7, 8). For one species the composition as to size and stage of maturity may change in the same way (D, fig. 8, 9, table 4). Regarding the depth distribution there are no species restricted to deeper layers. Below 100 m the number falls to about 1% of the uppermost layer. Oikopleura longicauda, 0. cophocerca, 0. parva and Althoffia tumida as well as Fritillaria species are found between 900 and 100 m in comparatively higher numbers than Stegosoma magnum, Oikopleura albicans and 0. intermedia (E, table 1, 2, 5)

Description: 1. Three species of the genus Acanthogorgia (Farn. Acanthogorgiidae) are known to occur in the eastern North Atlantic; two of them are described as new: granulata n. sp., pico n. sp., hirsuta GRAY. The latter was also found in the Mediterranean. 2.The three species are quite distinct in their morphological characters. Each is morphologically similar to a species of the West Atlantic. The three pairs are: hirsuta/aspera, granulata/muricata, and pico/armata.

Description: Diagnoses based on observations in light and electron microscopes of Gephyrocapsa ornata HEIMDAL n. sp., Alisphaera HEIMDAL n. gen., and A. ordinata (KAMPTNER) HEIMDAL n. comb. = Acanthoica ordinata KAMPTNER are given. The coccolith morphology of the new taxa as well as the probable relationship of G. ornata to previously described species, are considered.