ALBERT

Beschreibung: This article reviews the major findings of an intensive geological and geophysical study of the Brazilian margin and adjacent oceanic and continental areas. Most of the data fits well with standard plate models for Atlantic-type margins, with clearly recognizeable pre-rift, rift, proto-oceanic and oceanic stages. However there are significant problems regarding the nature of the crust beneath the margin and the position of the boundary between oceanic and continental crust.

Beschreibung: Males of Eledone cirrhosa grow to a size little over 600 g and normally have well-developed, and presumably active, reproductive organs from about 200 g upwards. Total weight of the genital bag is well correlated with total body weight (r= 0·906). Growth of the testis precedes that of the spermatophoric sac, and the size of neither of these reproductive components is predictable from body weight. The sizes of these organs and the estimated number and length of stored spermatophores are given for 100 g intervals of total body weight. No evidence was obtained for a seasonal trend in male maturity.

Beschreibung: Many of the difficulties of staining plastic embedded tissues for light and electron microscopy derive from physical exclusion of hydrophilic staining reagents by hydrophobic embedding media. Structures which stain most intensely with hydrophilic reagents usually contain less hydrophobic plastic than do non-staining structures. Such incomplete infiltration is apparently caused by exclusion of viscous, hydrophobic monomers by physically dense and/or well hydrated tissue elements. In keeping with this, generalized staining of tissues embedded in hydrophobic media does occur when hydrophobic reagents are used. Staining of plastic-free structures with single hydrophilic reagents or with sequences of such reagents, is, however, largely rate-controlled. The surprising similarity of hydrophilic and hydrophobic plastic embedding media is discussed. Limits of this simple model are explored, with a consideration of the roles of fixative and of monomer-tissue reactions

Beschreibung: Sonic transmitters coupled to depth-sensitive strain gauges and attached to shells of Nautilus belauensis in Palau, Western Caroline Islands, established net vertical movement between 85 and 467 m, and lateral movement of about 3km over a period of 7 days and nights. Generally, the animals were found in deep water during daytime and moved to shallower water at night.

Beschreibung: We present chemical data on magmatically heterogeneous pyroclastic deposits of late Quaternary age erupted from zoned magma systems underlying Tenerife (Canary Islands), Sao Miguel and Faial (Azores), and Vesuvius. The most fractionated magmas present at each centre are respectively Na-rich phonolite, trachyte, and K-rich phonolite. Within any one deposit, chemical variation is either accompanied by changes in the phenocryst assemblage (petrographic zonation) or is largely manifested in trace element abundances, unaccompanied by any petrographic change (occult zonation). Zoning is analogous to that in calc-alkaline systems where the most fractionated products are high-silica rhyolites. When a range of magma types are considered, a correlation emerges between roofward depletion of trace elements (especially REE) in the zoned system and compatability of those same trace elements in the accessory phenocryst phases present. Thus, allanite- or chevkinite-bearing rhyolitic systems are light-REE depleted roofwards, the sphene-bearing Tenerife system is middle-REE depleted roofwards, the melanite-bearing Vesuvius system is heavy-REE depleted roofwards, while the Azores systems, which lack these phases, display roofward REE enrichment. Therefore, the behaviour of trace elements may in each case be explained by fractionation of observed phenocryst assemblages. The resemblance between features of zoned magma systems and published work on the dynamic consequences of cooling saturated aqueous solutions prompts us to suggest that sidewall crystallization and consequent boundary-layer uprise to form a capping layer at top of the system may be a plausible mechanism for the generation of both petrographic and occult zonation. Reverse zoning occurs among the first-erupted tephra of some deposits, demonstrating that the most highly differentiated magma available is not always the first to be tapped during an eruption from a zoned system.

Beschreibung: The widespread occurrence of organic-carbon-rich strata (‘black shales’) in certain portions of Jurassic, Cretaceous and Cenozoic sequences has been well-documented from Deep Sea Drilling Project sites in the Atlantic and Pacific Oceans and from sequences, now exposed on land, originally deposited in the Tethyan ocean. These ancient black shales usually have been explained by analogy with examples of modern deep-sea sediments in which organic matter locally is preserved by (1) increasing the supply of organic matter, (2) increasing the rate of sedimentation, and/or (3) decreasing the oxygen content of the bottom water. However, detailed examination of many black shales reveals characteristics that cannot be explained by simple local models, including: their approximate coincidence in time globally; their occurrence in a variety of different environments, including open oxygenated oceans, restricted basins, deep and shallow water; their interbedding with organic-carbonpoor strata which often dominate a so-called black shale sequence; their deposition by pelagic, hemipelagic, turbiditic and other processes; and the variations in type and amount of organic matter that occur even within the same sequence. A more complex model for the origin of black shales therefore appears most appropriate, in which the cyclic preservation of organic matter depends on the interplay of the three main variables, namely supply of organic matter, sedimentation rate, and deep-water oxygenation, each of which varies independently to some extent. The variation and relative importance of these parameters in individual basins and widespread black shale deposition in general are linked globally and temporally by changes in global sea-level, climate and related changes in oceanic circulation. An important and often overlooked factor for the supply of organic matter to deep-basin sediments is the frequency and magnitude of redepositional processes. The interplay of these variables is discussed in relation to the middle Cretaceous and Cenozoic organic-carbon-rich strata, in particular, which show marked differences in the relative importance of the different variables.

Beschreibung: Changes in the relative size of the ovary, oviducal glands and eggs are described for Eledone cirrhosa captured from the North Sea off Aberdeen over a 3 year period (N = 488). The analysis is based only on freshly caught animals, excluding those held in aquarium conditions (〉 5 days). Ovary enlargement and egg size estimates are used as indices of sexual maturity. Between 0–15% and 18–95% of total body weight is contributed by the ovary. Maximum egg length in the ovary ranges up to 7 mm. On these criteria, sexual maturation typically occurs at body sizes between 400–1000 g although some animals of 1000–1200 g are found showing no evidence of ovary enlargement. The majority of the monthly sample is always immature but maturation can apparently occur at almost any time of the year. Increase in mean ovary index and mean values for egg size are strongly seasonal and indicate a peak incidence of sexual maturity over 2–3 months in the July-September period. Spawning is presumed to follow within 1 month. Estimates of the fecundity of the females, based on the egg sample from the ovary, range from 2·2 × 103 to 55 × 10 3 eggs with a mean of 11 × 10 3 and a mode of 7·5 × 10 3 eggs.

Beschreibung: Female Eledone cirrhosa held in aquarium conditions for periods of time of five daysand over show relatively enlarged ovary sizes. Values for ovary index considerably exceed thoseof freshly caught animals and the incidence of the final stage of maturity, in which eggs pack the oviducts, is greater. A comparison of maturity indices for fresh and aquarium males was inconclusive. The range of factors associated with aquarium conditions is briefly reviewed and it is concluded that studies of cephalopod reproductive maturation must distinguish fresh and aquarium animals. Introduction External factors effective in inducing sexual maturation in cephalopods have been suggested several times. The influence of the absence of light has been implicated since the experiments of Wells & Wells (1959) showed that blinded Octopus vulgar is matured precociously. An effect of short day length in stimulating the optic glands of Sepia has been found by Defretin & Richard (1967) and Richard (1967) but this is not clearly the case for Octopus (Buckley, 1977). Octopuses kept in aquarium conditions for lengthy periods are said to have larger relative gonad sizes than those fresh from the sea (Wells & Wells, 1975). One of the factors associated with aquarium conditions is often a degree of starvation, and this circumstance alone is held to be a factor in inducing precocious sexual maturation in Eledone (Mangold & Boucher-Rodoni, 1973). In the course of recent studies on the growth and reproduction of Eledone cirrhosa from the North Sea (Boyle & Knobloch, 1982,1983,1984) animals which had remained in aquarium conditions for 5 days or over were separated from the analysis.

Beschreibung: Harpoon-like setae from the polychaete scale-worm, Hermione hystrix, were found embedded deeply in the brain of Octopus vulgaris. The setae had passed across the cuticular lining and muscles of the oesophagus before entering the surrounding soft nervous tissues. Further investigation showed that Octopus will eat Hermione, confirming other reports that polychaetes form part of the diet of octopods.

Beschreibung: Several specimens of the remarkable finned octopod Cirrothauma recently caught are described. The animal is taken at great depths, often near the bottom but sometimes away from it. The enormous arms and web can be spread to give a medusoid form but the animal also swims horizontally mainly using the fins, whose powerful muscles are attached to a large fin support. The animal is gelatinous and perhaps neutrally buoyant, and can almost certainly hover in the medusoid form. The mantle muscles are weak and the funnel very long. The arms are long and have a few small suckers in a single longitudinal row, only some of which have a minute suction chamber. The infundibula are small but the cuticle has small pegs with innumerable pores. The cuticle is closely similar to that of octopods and is capable of adhesion. In the base of each sucker peduncle, male and female, there is a possible light organ. The beaks are large and black, the lower strongly pointed. There is a large tongue with vestiges of a radula. The salivary papilla carries the duct of the `posterior salivary gland' which lies far forward within the buccal complex. The male ducts are simple and produce simple packets of sperms. These are found in the oviducal gland (spermatheca), where the large eggs are fertilized. The heart has an accessory chamber presumably providing extra blood flow to the long arms and large fins. The eyes are small open cups covered by a cornea but with no lens or iris. The rhabdomes are sometimes degenerate. The optic lobe is small with no granular layers of amacrine cells. The suboesophageal lobes are close together and the superior buccal lobe is attached to the brain, as in incirrate octopods. There is a large fin lobe. The peduncle lobe and basal lobes are large, in spite of the small eyes, indicating their importance for locomotion. There are no giant fibres. The supraoesophageal lobes are small, with development only of the tactile region (inferior frontal lobe) and reduction of the superior frontal and vertical lobe system. There are large epistellar bodies but no cranial photosensitive vesicles. The optic gland is clearly of neural origin. The statocysts are very large and typically octopodan with a single macula and one anticrista, but the crista is not subdivided. Cirrothauma, like other cirrates, thus shows some features that are present in Vampyroteuthis, and others that are found in decapods, as well as many present in the octopods without fins. These animals represent in some ways an early condition of the coleoid stock.

Beschreibung: The well-known caldera of Thira (Santorini), Greece, was not formed during a single eruption but is composed of two overlapping calderas superimposed upon a complex volcanic field that developed along a NE trending line of vents. Before the Minoan eruption of 1400 B.C., Thira consisted of three Java shields in the northern half of the island and a flooded depression surrounded by tuff deposits in the southern half. Andesitic lavas formed the overlapping shields of the north and were contemporaneous with and, in many places, interbedded with the southern tuff deposits. Although there appears to be little difference between the composition of magmas erupted, differences in eruption style indicate that most of the activity in the northern half of the volcanic field was subaerial, producing lava flows, whereas in the south, eruptions within a flooded depression produced a sequence of mostly phreatomagmatic tuffs. Many of these tuffs are plastered onto the walls of what appears to have been an older caldera, most probably associated with an eruption of rhyodacitic tephra 100,000 years ago. The Minoan eruption of about 1400 B.C. had four distinct phases, each reflecting a different vent geometry and eruption mechanism. The Minoan activity was preceded by minor eruptions of fine ash. (1) The eruption began with a Plinian phase, from subaerial vent(s) located on the easternmost of the lava shields. (2) Vent(s) grew toward the SW into the flooded depression. Subsequent activity deposited large-scale base surge deposits during vent widening by phreatomagmatic activity. (3) The third eruptive phase was also phreatomagmatic and produced 60% of the volume of the Minoan Tuff. This activity was nearly continuous and formed a large featureless tuff ring with poorly defined bedding. This deposit contains 5–40% lithic fragments that are typical of the westernmost lava shield and appears to have been erupted when caldera collapse began. (4) The last phase consisted of eruption of ignimbrites from vent(s) on the eastern shield, not yet involved in collapse. Collapse continued after eruption of the ignimbrites with foundering of the eastern half of the caldera. Total volume of the collapse was about 19 km3, overlapping the older caldera to form the caldera complex visible today. Intracaldera eruptions have formed the Kameni Islands along linear vents concomitant with vents that may have been sources for the Minoan Tuff.

Beschreibung: A new species of a monogenean Isancistrum subulatae (Gyrodactylidae) has been discovered on the arms and tentacles of the cephalopod mollusc Alloteuthis subulata at Plymouth and I. loliginis, on the gills of the same host, has been re-discovered for the first time since its original description in 1912. I. subulatae, like other gyrodactylids, is viviparous, and has been shown by experiments to transfer to new hosts by contagion. In nature such transfers probably take place during copulation of the hosts and since the parasite may occur in numbers of several thousands per host, it may thereby constitute a venereal disease.

Beschreibung: The feeding biology was investigated of a population of the nordic krill Meganyctiphanes norvegica which inhabits a semi-enclosed deep near the danish island Läsö. The food composition was determined during one year in monthly samples. The analysis of the stomach contents showed a remarkable diversity. Cannibalism is common, Detritus and undigestible matter form a major part of the compounds at all times of the year. The investigation of the feeding appendages gave evidence that the spectrum of food particles fed is determined by the mechanical properties of the fil tering basket. Optical control of the food is not possible because of the insufficient resolution of the eyes. This explanation of the unspecific food requirements was supported by observations on the feeding behavior. The eyes reveal a high sensibility to perceive even very dim light in contrast to their poor resolution of fine details. This feature illustrates the major role of the eyes in the control of vertical migration and orientation. Quantitative aspects of the feeding biology are dealt within the last chapter. The determination of the amount of food contained in the stomachs allowed to quantify the feeding intensity of the nordic krill. A energy budget based on recent findings is presented and its reliability discussed.

Beschreibung: The behaviour of Chelophyes has been analysed from the point of view of coordination between stem and nectophores, and an electron microscope study of the effectors and conducting elements has been carried out. Coordination between the stem and anterior nectophore involves two pathways, one epithelial and the other nervous. The nervous link consists of a bundle of small neurites and a single giant axon. There is some evidence that this mediates rapid escape behaviour. After the nerves have been cut, coordination is maintained via the epithelial route. Impulses can jump from epithelial cells into nerves but the transmission process is unclear. Neuro‐epithelial transmission involves conventional synapses. As in physonectid siphonophores, the stem has two nervous systems each with its own giant fibre, and a slow system, the endodermal epithelium. In the nectophore, marginal nerve centres generate a swimming rhythm. Conduction in the subumbrellar muscle is myoid. The exumbrellar epithelium and the subumbrellar endoderm are conducting tissues. Histological study reveals synapses in the predicted locations and gives details of myo‐epithelial organization and nervous layout. Novel histological features include elements resembling steroid‐secreting cells, which ensheath nerves and are innervated by them, and innervated giant non‐nervous cells lying between the nerve ring and the hydroecium. The subumbrellar muscle cells are shown to have sarcolemmal invaginations reminiscent of the f‐tubule system of vertebrate muscle.

Beschreibung: A program of geophysical research was carried out as a preliminary stage of study of the Santorini volcanic group. This area is of remarkable geothermal and volcanological interest, and the definition of a volcanological structural model is the starting point for an understanding of the local geodynamic processes. Gravity, magnetic and geoelectrical data proved that: (i) the core of the volcanic edifice consists of a sedimentary-metamorphic basement; (ii) the basement is tectonically disturbed and a linear tectonic system produces a graben-type structure in the middle part of the area.

Beschreibung: Die Probleme, die bei Speciesuntersuchungen von Spurenelementen mit Hilfe der Differentialpuls Anodic Stripping Voltammetrie auftreten, werden zu-sammenfassend dargestellt. Neben den bei der eigentlichen Bestimmung auftretenden Problemen, werden auch solche erwähnt, die mit der Probennahme sowie der Lagerung und Vorbehandlung der Proben in Zusammenhang stehen.

Beschreibung: 1. PCBs were administered to juvenile soles (Solea solea) with food. Homogenates of gut, liver, brain, dark skin, muscle and gills were analysed for their contents of individual PCB components. The relative contributions of individual components to total PCB were virtually indentical in the various organs sampled at the same day in a 275-day period. 2. During the experiment concentrations on a (pentane-extractable) lipid basis of most PCB components declined in all organs regardless of lipid metabolism. The results suggest that PCB patterns in organs are determined by equilibrium partitioning. So components remained mobilizable from organs whose lipid contents increased. This is in contrast with the idea that PCBs are taken up and stored in lipids under circumstances of increasing lipid content in organs. 3. The plateau-values of the steady-states of lipid based concentrations of PCB components decreased in all organs. This might have been due to changes in lipid contents or lipid composition in some organs.

Beschreibung: We studied the alteration of silicic volcanic glass of recent Towada ash in the different soil environments by means of electron-microprobe analysis. Two types of glass alteration (tentatively named [alpha] and [beta] types) were established and were distinguished on the basis of potassium and calcium contents of the glass samples. The [alpha] type glass alteration was characterized by a very large gain of potassium and a large loss of sodium. This alteration was explained by the ion exchange reaction between Na+ and H+ plus K+ without significant change in the glass structure. The [beta] type alteration characteristically showed a significant loss of potassium and a large gain of calcium and some other elements. The behaviors of alkalies and alkaline earths in the [beta] type glass could not be interpreted by the stoichiometry of exchange processes of these elements. Changes of glass structure during weathering were suggested for the [beta] type glass. There were close relationships between the mode of glass alteration, clay mineralogy of ash-derived soils, and soil environments. Only [alpha] type glass alteration was observed in the 2:1 mineral soils that showed the very low pH, very low contents of exchangeable bases, but relatively high content of exchangeable potassium. In contrast the [beta] type glass alteration was the most intense in the allophanic Ando soil, which showed a relatively high content of exchangeable bases and a high pH.

Beschreibung: The boundaries of the mud area of the inner German Bight have been mapped w1th a subbottom echo sounder. The echo profiles reveal a uniform sediment body which is chararterized by the occurrence of mud (clayey silt) in separate layers. The western part of the area is dominated by mud showing fine-sand intercalations, the well-known storm sand layers. The eastern part consists of fine-sand /mud alternate bedding. Primary stratification may be altered by bioturbation, particularly in the western part. However, the echographic uniformity of the mud area is almost independent of the regional variations of facies. At the southern, western, and northern boundaries the mud-area sediment body wedges out above the adjacent, more sandy sedimems. The eastern boundary is a system of sand tongues and channels with fine-sand/mud alternate bedding. Here, interfingering of sand and sand/mud facies may be a typical pattern in the depositional sequence due to occasional shifting of both sand tongues and channels. Based on hydrographic data from the German Bight the origin of the mud was ascribed mainly to the suspension load of the river Elbe. The suspended matter is transported towards north by the "Elbe water mass" which is a particular water body with lower salinity, as compared with surrounding North Sea waters. Main part of the suspension load is, however, deposited in the inner German Bight. The limits of mud deposition are given by the western and eastern boundaries of the "Elbe water" body as well as by shallower sand ridges surrounding the mud area in the south, east, and west.

Beschreibung: Study of Nautilus belauensis i its natural habitat in Palau, West Caroline Islands, shows that growth is slow (0.1 millimeter of shell per day on the average) and decreases as maturity is approached and that individuals may live at least 4 years beyond maturity. Age estimates for seven animals marked and recaptured between 45 and 355 days after release range from 14.5 to 17.2 years. These data indicate that the life-span of Nautilus may exceed 20 years and that its life strategy is very different from that of other living cephalopods.

Beschreibung: Abundance and size of manganese nodules lying on the ocean ftoor can be computed from multi-frequency sounding data from a survey vessel. This paper shows how individual nodule scattering response is synthesized to obtain equivalent reftectivity of nodule deposits. Then quantitative ways of measuring nodule coverage or abundance are developed so that they can be linked to acoustic responses. Examples are worked out and the Sumitomo method of synthesizing acoustic response is described.

Beschreibung: Although motion between Arabia and Africa is presently occurring along the entire length of the Red Sea, the morphology and tectonics that result from this motion vary greatly along its length. South of 21°N, the main trough is bisected by a deep axial trough which has formed by sea-floor spreading during the past 4 m.y. and is associated with large-amplitude magnetic anomalies and high heat flow. North of 25°N, an axial trough is not present and the floor of the main trough has an irregular faulted appearance. The magnetic field in the north is characterized by smooth low-amplitude anomalies with a few isolated higher amplitude magnetic anomalies commonly associated with gravity anomalies and in many places probably due to intrusions. Between these regions, the axial trough is discontinuous with a series of deeps characterized by large-amplitude magnetic anomalies alternating with shallower intertrough zones which lack magnetic anomalies. It is argued that the different regions represent successive phases in the rifting of a continent and the development of a continental margin. An initial period of diffuse extension by rotational faulting and dike injection over an area perhaps 100 km (60 mi) wide is followed by concentration of extension at a single axis and the initiation of sea-floor spreading. The main trough in the southern Red Sea, away from the deep axial trough, formed during the Miocene by the same processes of diffuse extension that are still active in the northern Red Sea. This model explains the available geologic and geophysical data and reconciles previous models for the formation of the Red Sea which emphasize either the evidence for considerable motion between Arabia and Africa or the evidence for down aulted continental crust beneath much of the Red Sea. The initial pre-sea-floor spreading stage results in considerable extension (160 km or 100 mi) at 25°N in the Red Sea), can last for several tens of millions of years, and is an important factor in the development of the continental margin. Such an extended phase of rifting and diffuse extension must be taken into account in studies of sedimentation, subsidence, and paleotemperatures.

Beschreibung: This paper reviews the status of mining offshore for sand and gravel on a world-wide basis. It discusses the technology for exploration and evaluation of sea floor mineral targets, as well as mining, transportation, and processing. Large operations in Japan and Europe are described, based upon personal observations of the author. The U.S. situation is outlined and opinions offered as to the outlook for the future.

Beschreibung: The islands of Ios and Naxos in the Cycladic archipelago, Greece, contain elongate domes over which a pervasive north- to north-northeast–stretching lineation is warped. These islands may be metamorphic core complexes of Cordilleran type, involving middle-crustal rocks drawn upward and outward from underneath the sedimentary basins now 100 km to the south. From ca. 25 Ma onward, during uplift, the crystalline rocks now exposed on the islands were deformed noncoaxially in the deeper levels of a major shallow-dipping ductile shear zone. This shear zone may have connected with low-angle normal faults in its upper levels, because it is probable that its later history involved the metamorphic complexes being dragged out from under a stretching and fracturing upper plate composed mainly of unmetamorphosed sedimentary and ophiolite suite rocks. This model can be extended to explain the exhumation of the high-pressure–low-temperature metamorphic rocks on Crete, which, with the Cyclades, forms a distended paired metamorphic belt separated by an active sedimentary basin.

Beschreibung: During a recent deep ocean research expedition, conducted by International Underwater Contractors, an important research project utilized the world's deepest, unmanned, untethered vehicle called the Epaulard. This Remotely Operated Vehicle (ROV) is capable of descending to 6100 meters; conducting a straight, grid or complex pattern survey over 12 nautical miles while taking 5000 high-quality black white photographs; and then ascending to the surface for recovery. It uses the latest in microprocessor technology to control its onboard components. The project took place in the summer of 1983 approximately 113 kilometers offshore Coos Bay, Oregon, in excess of 3600 meters of water. It was conducted in the area known as the Gorda Rift and the Juan de Fuca ridge where previous surveys have indicated the possibilities of significant amounts of polymetallic sulfides. The mission was considered a total success because the vehicle was able to take approximately 15,000 photos over a 5-day mission.

Beschreibung: On the fluoride budget of euphausiids. Investigations on Meganyctiphanes norvegica (M. Sars) and Euphausia superba Dana various aspects of the fluoride occurrence in euphausiids were chiefly examined in maintenance experiments: Fluoride uptake, release, toxicity, accumulation, dynamics during the mault cycle and function. Krill takes up dissolved fluoride quantitatively from seawater. A potential uptake via food can be neglected as a model calculation shows. The fluoride uptake was quantified for norvegica by F- analysis of experimental water. Fluoride was released rapidly from dissected cuticle and exuviae, respectively (70% and 50% of the initial value in the course of 4 hours, resp.). In dead individuals, however, the F- release was strongly delayed (40% in the course of 4 hours). The loss of the organic portion in any case proceeded more slowly and therefore reveals no direct connection with the F- liberation. The possible chemical binding in the cuticle is discussed. A raised amount of fluoride in the experimental tanks from 5 mg/1 up caused significant mortality. Dependent on the exposure time an additional fluoride accumulation took place which more than doubled the normal F- values of the carapace. More than 99% of the total fluoride in an individual is bound in the cuticle, as a balance estimation shows. The p- content of the cuticle only changes for a short period directly before (F- decrease) and after exuviation, during the synthesis of the new shell F- increase), and otherwise remains constant. Maintenance for several weeks in fluoride-free artificial seawater did not affect survival rates of experimental animals as compared to controls. Accordingly, fluoride appears not to have a vital function for krill. It is hypothesized that the significance of fluoride for euphausiids is its functional property as a structural element of a common type of skeletal construction in marine invertebrates to which high contents of phosphate and protein are characteristic.

Beschreibung: We have compiled both laboratory and worldwide field data on electrical conductivity to help understand the physical implications of deep crustal electrical profiles. Regional heat flow was used to assign temperatures to each layer in regional electrical conductivity models; we avoided those data where purely conductive heat flow suggested temperatures more than about 1000°C, substantially higher than solidus temperatures and outside the range of validity of heat flow models. The resulting plots of log conductivity σ versus 1/T demonstrate that even low-conductivity layers (LCL) have conductivities several orders of magnitude higher than dry laboratory samples and that the data can be represented by straight line fits. In addition, technically active regions show systematically higher conductivities than do shield areas. Because volatiles are usually lost in laboratory measurements and their absence is a principal difference between laboratory and field conditions, these materials probably account for the relatively higher conductivities of rocks in situ in the crust; free water in amounts of 0.01–0.1% in fracture porosity could explain crustal conductivities. Other possibilities are graphite, hydrated minerals in rare instances, and sulfur in combination with other volatiles. As most of the temperatures are less than 700°C, partial melting seems likely only in regions of highest heat flow where the conductive temperature profiles are inappropriate. Another result is that at a given temperature, crustal high-conductivity layers (HCL) are more conductive by another order of magnitude and show more scatter than do LCL's. Because the differences between HCL's and LCL's are independent of temperature, we must invoke more than temperature increases as a cause for large conductivity increases; increased fluid concentration in situ seems a probable cause for enhanced conductivities in HCL's. From the point of view of these observations, it does not matter whether the fluids are in communication with the surface or trapped at lithostatic pressures.

Beschreibung: The exchange of inorganic nutrients; ammonium, nitrate and reactive phosphate between burrows of the infaunal polychaete Nereis virens Sars and the overlying water was assessed using V-shaped sediment cores. Exchange was determined by monitoring ventilation current and nutrient concentration of in- and excurrent water. Ammonium supply appeared independent of overlying water concentrations, showing a constant release of 0.5 μmol·h−1 (for a 2-g individual + burrow system) at concentrations from 2 to 87 μM. Of this release ≈40% originated from worm excretion, and the rest from microbial mineralization. Nitrate and phosphate exchange appeared very sensitive to overlying water concentrations, having equilibrium (zero flux) at 10–15 and 3 μM, respectively. Below these concentrations nitrate showed a slight release (due to nitrification), whereas phosphate was released at a rate of 3.2 × 10−2 μmol·h−1 at 1 μM (mineralization and desorption). Above equilibrium they both were removed during water passage through worm burrows, reaching 0.4 μmol·h−1 for nitrate at 107 μM (nitrate reduction) and 3.7 × 10−2 μmol·h−1 for phosphate at 5.6 μM (adsorption processes). The burrow system apparently acted as a buffer for phosphate and, to some degree, nitrate in the overlying water. At the study site (Norsminde Fjord estuary) nereid burrows were estimated to increase the sediment-water interface 150%. About 17% of the water column was cycled through the sediment by Nereis each day. The worm + burrow system was estimated to release 95 μmol· m−2·h−1 ammonium to the overlying water, which was ≈76–90% of the total release of ammonium from the sediment (30–36% was worm excretion).

Beschreibung: Isopach asymmetry, and sediment component changes in DSDP cores from the SE Atlantic (Orange Basin) support the hypothesis of major drainage system changes in SW Africa during late Cretaceous—Cenozoic time. This involved alternations in the use of the 28°S (modern Orange River) and 31°S (modern Olifants River) exit points across the western escarpment by rivers carrying run-off from the Upper Orange/Vaal catchment areas, as well as radical re-organizations of internal drainage geometry. It is postulated that during late Cretaceous times the 28°S exit was used, with the Middle Orange River following a course in the interior well to the south (up to 150 km) of its modern channel. Sediment discharge rates from this river were relatively high (at least 10 × 106 m3 yr−1), and resulted in rapid advancement of the continental margin sediment prism west of the mouth by large-scale slumping. The Palaeogene Orange/Vaal river exit was via the 31°S escarpment crossing, and during the later part of this period, the Cape Canyon was cut across the continental shelf and slope. A significant reduction in sediment discharge (to 2.0 × 106 m3 yr−1) suggests that the Lower Tertiary climate for SW Africa was drier than that of late Cretaceous times. However, aridity did not commence until late Miocene times, when the Orange/Vaal discharge had switched back to the 28°S exit. Modern sediment discharge rates (6.5 × 106 m3 yr−1) are relatively high and reflect soil erosion caused by agricultural activity. The two major alterations in exit point of the Orange/Vaal (late Cretaceous—early Tertiary, and late Oligocene—early Miocene) are related to periods of low sea level, which promoted river capture adjacent to the western escarpment. An additional factor in the first course change may have been the disruption of the Middle Orange channel by late Cretaceous igneous intrusions. Less important internal reorganizations of the drainage system are postulated in late Miocene—Pleistocene times. Economic implications for offshore diamond distribution are briefly mentioned.

Beschreibung: Geostrophic transports in the eastern subtropical North Atlantic computed from historic hydrographic data and recent CTD measurements show a mean transport in the subtropical gyre of 11 ± 1.5 × 106 m3 s–1 in the upper 1000 m between 35W and the African coast. The dynamic method was used in conjunction with a conservation of mass scheme (Fiadeiro and Veronis, 1982) to determine the level of no motion. This level lies in the 1200 m depth near the Azores and drops to 1500 m in the tropics. The main inflow enters south of the Azores as a relatively narrow current, turns southward at the latitude of Madeira and then widens. Three current bands transport the water southward. North of the Cape Verde Islands, the current turns westward. This part of the North Equatorial Current extends more to the south in the upper 200 m than in the 200–800 m layer. The Portugal current, between the Azores and the Portuguese coast, which is thought by some to be strong, is seen here as a relatively weak flow. Maps of potential vorticity derived from smoothed density profiles are consistent with the general pattern of geostrophic transport.

Beschreibung: Reovirus 3 in the presence of foetal bovine serum was exposed to six disinfectants for times of 10, 20 and 30 sec. At the end of such exposure times the addition of skim milk terminated disinfectant activity, and residual virus was assayed using the plaque technique. The six disinfectants considered were Javex (a sodium hypochlorite disinfectant), sodium hydroxide, ethanol, Wescodyne, One Stroke Ves-Phene, and Sonacide. Ethanol (95% v/v) and 1/75 Javex (800 ppm chlorine) were the most effective virucides. Both of these agents inactivated 10(5) plaque forming units (PFU) in 30 sec. Undiluted Sonacide, 0.25% (w/v) sodium hydroxide and 1/200 Wescodyne each inactivated between 10(2) and 10(3) PFU in 30 sec. Javex at a dilution of 1/100 (600 ppm chlorine) was next in effectiveness, inactivating 10(1.5) PFU in 30 sec and was more effective than 1/50 Ves-Phene which inactivated 10(1) PFU in 30 sec. Ethanol in 70% (v/v) solution was totally ineffective in inactivating reovirus 3. Ethanol (95% v/v) after dilution in the test system was 76% (v/v) and ethanol (70% v/v) was really 56% (v/v) The effectiveness of six disinfectants in inactivation of reovirus 3.. Available from: http://www.researchgate.net/publication/16667970_The_effectiveness_of_six_disinfectants_in_inactivation_of_reovirus_3 [accessed Oct 6, 2015].

Beschreibung: Die Reise diente der methodischen Untersuchung der Dämpfung und der Geschwindigkeit seismischer Wellen und ihrer Abhängigkeiten von der Frequenz in oberflächennahen Sedimenten. Hierzu war es erforderlich, verschiedene seismische Quellen mit unterschiedlichen Signalspektren (Uniboorn, Sparker, Airgun) auf den selben Profilabschnitten einzusetzen. Daneben wurden seisrnostratigraphische Untersuchungen an aus früheren Reisen bereits bekannten Strukturen (z.B. Stauchmoränen, halokinetisch beeinflußte Strukturen nördl. Helgoland) durchgeführt. Diese Strukturen wurden auf dieser Reise erstmals digital aufgezeichnet und sind so genauerer Analyse zugänglich. Zur Bestimmung der Verteilung von Schwermetallen im Sedimentationsgebiet der Elbe wurden entlang des Elbe-Urstromtals Bodenproben entnommen.

Beschreibung: Die 94/2. Forschungsreise diente der Fortführung zoologischen Untersuchungen an der Bodenfauna des Kattegat und Skagerrak, sammeln von wirbellosen Meeresorganismen für die Forschung und Lehre sowie die Erprobung einer weiterentwickelten Stromprofilsonde DPS auf Wassertiefen über 500 m.

Beschreibung: Die Ausreise von FS "Poseidon" vom 2.7. bis 9.7.82 fand in das Skagerrak statt, um die dort auf FS "Gauß" im Jahr 1980 begonnenen mehrkanaligen reflexionsseismischen Messungen fortzusetzen. Dabei sollte vor allem die Struktur der Norwegischen Rinne im westlichen Skagerrak aufgenommen werden. Gleichzeitig diente diese Ausreise der praktischen Ausbildung von sieben indischen Gastwissenschaftlern im Bereich der marinen Geophysik, die als begleitende Maßnahme zum Bau eines indischen Forschungsschiffes bei der Schlichting Werft in Travemünde durchzuführen war. Die Gastwissenschaftler kamen von verschiedenen Institutionen des "Geological Survey of India" (=GSI) und vom "National Institute of Oceanology" in Goa. Obwohl dies Training der indischen Gastwissenschaftler ein wichtiger Bestandteil des Programms war, ließ es sich doch gut mit der Durchführung des Forschungsvorhabens verbinden.

Beschreibung: In order to collect relevant environmental data in the fishing area off southern Angola, the "R/V "GOA" made three cruises in the area in November 1970 and March and July 1971

Beschreibung: A number of moderately halophilic bacteria of diverse taxonomic groups have been studied to determine the intracellular concentrations of organic compounds at various salt concentrations. Betaine was accumulated in all of these organisms in proportion to the salinity of the medium, suggesting that this compound plays a major role in osmoregulation.

Beschreibung: The amino acid composition of total proteins of eight Ectothiorhodospira strains with different salt optima and of separated membranes of selected strains have been determined. Amino acid compositions were compared with those reported for nonhalophilic phototrophic and heterotrophic bacteria and Halobacterium halobium. The membrane fractions from Ectothiorhodospira strains requiring high salt for maximum growth contained more polar and less nonpolar amino acids than strains with low salt requirements or nonhalophilic bacteria. The content of intermediate amino acids increased with the increasing halophilic properties of the Ectothiorhodospira strains. Proteins which function in high-salt environments may therefore require such compositions to maintain their structures in highly ionic solutions.

Beschreibung: The mechanism of sulfate assimilation was investigated in Rhodopseudomonas sulfidophila, a bacterium able to grow either photoautotrophically, with sulfide as electron donor, or photoheterotrophically with sulfate as sole sulfur source. ATP sulfurylase, adenosine-5′-phosphosulfate kinase, 3′-phosphoadenosine-5′-phosphosulfate sulfotransferase, thiosulfonate reductase and cysteine synthase were present. Reduced sulfur compounds, especially sulfide and sulfite repressed all steps of sulfate activation and reduction including sulfate uptake. Adenosine-5′-phosphosulfate kinase activity in contrast to the other activities was high in the presence of cysteine or reduced glutathione in the growth medium. Sulfur was incorporated into the cellular sulfolipid from sulfate and also from reduced sulfur compounds like cysteine and thiosulfate. The activity of 3′-phosphoadenosine-5′-phosphosulfate sulfotransferase was rapidly lost during gel filtration or dialysis. From comparison with other sulfotransferases and from the specific cofactor requirement for the enzyme of R. sulfidophila it is concluded that two different low molecular weight cofactors are required in this system. A reaction sequence is proposed involving thioredoxin as the reductant of another dialysable low molecular weight cofactor, that binds to the protein.

Beschreibung: A new purple nonsulfur bacterium was isolated from enrichment cultures of a sulfide-containing marine lagoon. The bacterium is similar to Rhodopseudomonas capsulata and is described as a new species of the genus Rhodopseudomonas: Rhodopseudomonas adriatica. Cells are non-motile, 0.5–0.8 μm by 1.3–1.8 μm, and multiply by binary fission. Intracytoplasmic membranes are of the vesicular type. The photosynthetic pigments are bacteriochlorophyll a and carotenoids of the spheroidene group. Growth is possible anaerobically in the light and at low pO2 in the dark. Biotin and thiamine are required as growth factors. A wide variety of organic compounds, as well as sulfide and thiosulfate, are used as photosynthetic electron donors. Sulfide is oxidized to elemental sulfur, which is subsequently converted to sulfate, whereas thiosulfate oxidation occurs without measurable intermediate. Rhodopseudomonas adriatica is unable to assimilate sulfate, growth is only possible in the presence of a reduced sulfur compound.

Beschreibung: Seven strains of five species of the genus Ectothiorhodospira were characterized by oligonucleotide cataloguing of their 16S rRNA in order to determine the phylogenetic relationship to one another and to other phototrophic purple bacteria. All representatives of Ectothiorhodospira are members of that line of descent defined by phototrophic purple sulfur bacteria and relatives, showing a moderate relationship to those phototrophic organisms forming globules of elemental sulfur inside the cell (Chromatium and relatives). The 5 Ectothiorhodospira species fall into two subgroups. E.halophila, E. halochloris and E. abdelmalekii form one, E. mobilis, E. shaposhnikovii and the unnamed strain BN 9906 form the second subgroup. Within the two subgroups the strains are closely related, while the degree of relatedness found between members of the two subgroups is more distant.

Beschreibung: Radiative transfer modelling for a coupled ocean-atmosphere system near 685 nm indicates a sufficiently high fluorescence signal of the chlorophyll a transmitted to the top of the atmosphere. However, only the shortwave half is seen at the top of the atmosphere, the longwave half is fully masked by atmospheric oxygen and water vapour absorption. The impact of atmospheric aerosol extinction on the signal transmission is almost negligible. The Hα line of the sun, atmospheric water vapour absorption, and chlorophyll absorption near 670 nm influence radiative transfer in the shortwave tail of the fluorescence line making the search for a baseline in order to eliminate the background radiation a difficult task.