ALBERT

Description: A 0.25 m**2 United States Naval Electronics Laboratory box corer was used to take replicate samples from an oligotrophic bottom under the North Pacific Central Water Mass (~28°N, 155°W). The bottom is a red clay with manganese nodules at a depth of 5500-5800 m. Macrofaunal density ranges from 84 to 160 individuals per m**2 and is therefore much the same as in Northwest Atlantic Gyre waters. Of the macrofaunal taxa, polychaetes dominate (55 %), followed by tanaids (18 %), bivalves (7 %), and isopods (6 %). Meiofaunal taxa were only partially retained by the 297 µm screen used in washing. Even then, they are 1.5-3.9 times as abundant as the macrofaunal taxa, with nematodes being numerically dominant by far. Foraminifera seem to comprise an important portion of the community, but could not be assessed accurately because of the inability to discriminate living and dead tests. Remains of what are probably xenophyophoridans are also very important, but offer the same problem. Faunal diversity is extremely high, with deposit feeders comprising the overwhelming majority. Most species are rare, being encountered only once. The distributions of only three species show any significant deviation from randomness. The polychaete fauna from box cores collected from 90 miles to the north was not significantly different from that of the principal study locality. Concordance appeared at several taxonomic levels, from species through macrofaunal/meiofaunal relationships. As a result, the variation in total animal abundance shows aggregation among cores. We discuss Sokolova's concept of a deep-sea oligotrophic zone dominated by suspension feeders, and reconcile it with our present findings. The high diversity of the fauna combined with the low food level contradict theories that relate diversity directly with productivity.

Description: Small glassy spheres, ellipsoids, teardrops, cylinders and dumbbells occur in large numbers in Tertiary deep sea clays cored in the northeastern Pacific by the Deep Sea Drilling Project. These objects morphologically resemble microtektites, but have the composition of an oceanic tholeiite. On the basis of their composition and stratigraphic relationship it is considered that they are of volcanic origin and most likely have been formed in deep water by submarine volcanic processes.

Description: For temperature investigations, a core in the Mediterranean Sea (No 189 of the Swedish Deep-Sea Expedition 1947-1948) was sampled at approximately 10 m intervals. Globigerina dubia, G. inflata and Globigerinoides rubra were seperated from each sample and their test were investigated for stable oxygen isotopic measurement. Oxygen isotopic analysis showed the following: 1) Ten stages are indicated. 2) The temperature minimum of stage 2 corresponds to a racliocarbon age of 17,200 years. 3) Temperature maxima of odd stages are about equal to the modern August mean, except that of stage 5 which is considerably higher and, probably reflects the influx of ice melt water. 4) Temperature minima of even stages are all very low, especially that of stage 2, and reflect conditions similar to those now prevailing around Newfoundland. 5) The temperature record indicates that during most of the time covered by the core, the Mediterranean was cooler than at present and that conditions similar to the present occurred only during comparatively short intervals. 6) Minor temperature fluctuations occur, especially in the warmer stages, which are of doubtful significance. 7) An average rate of sedimentation of 4.3 cm/1000 years is indicated for the whole core.