Chemistry of interstitial waters of samples from DSDP Leg 25

Interstitial water analyses from sediments collected during Leg 25 of the Deep Sea Drilling Project have revealed that in the southwest Indian Ocean, great chemical activity exists in sediments in various depositional environments. Variable sedimentation rates allow us to set some interesting boundary conditions on chemical and transport processes in these interstitial waters, particularly with regard to the distribution of dissolved sulfate. In terrigenous rapidly deposited sediments, large depletions are observed in magnesium and potassium, whereas relatively small decreases in dissolved calcium occur. In slowly deposited detrital sediments, also, large decreases in potassium and magnesium coincide with very large calcium increases. In truly pelagic sediments, a one to one replacement of magnesium by calcium is observed in the interstitial waters, presumably due to reactions in the basal sediment layers. Biogenous deposits have great influence on dissolved silica (sponge spicules and radiolarians) and on dissolved strontium (carbonate recrystallization). Otherwise, dissolved silica reflects the clay mineralogy and shows variations which seem particularly dependent on the presence or absence of kaolinite. Variable dissolved manganese values reflect reducing conditions and/or availability of manganese in the solid phases for mobilization in reducing sediments.

Chemical composition of bottom sediments and rocks from DSDP Holes 3-14 through 64-477

Data on analyses of chemical composition of DSDP samples of bottom sediments and rocks carried out in P.P. Shirshov Institute of Oceanology are reported. Basal sediments and sedimentary rocks prevail in the sample set.

Ages, lithologie descriptions and mineral analyses from different DSDP holes in the Indian Ocean

The present work is based on mineralogical studies of sand and silt layers from a number of Deep Sea Drilling Project sites in the Indian Ocean belonging to different physiographic provinces of different ages. The minerals can be grouped into two major associations: a hornblende-opaque association with varying amounts of pyroxene, garnet, epidote, zircon, etc. and a biotite-chlorite-muscovite assemblage. The dominance of unstable minerals indicates a first generation, though evidence of reworking is reflected in the zircon and tourmaline grains at some sites. A large variety of minerals at some sites indicates a complex source. The mineral composition is nearly homogeneous at different sites for the entire length of the core, indicating that they have been derived from the same source during the deposition of that interval. However, the provenance changed by tectonic activity, the effect of which has been reflected in the mineralogy of some sites. An attempt was made to describe the mineralogic characteristics and their tectonic interpretations in the Pliocene and Miocene periods in the Ganges and Indus fan sites and also in the Wharton and Mozambique basin sites. Similar attempts could not be made for other ages in other physiographic provinces as the numbers of samples were too few. Within the limited scope, some idea about the mineralogical character of different basins and different physiographic provinces can be obtained from the present study. Mineralogical evidence also suggests very long transport of sediments in the deep sea. Regional variation of mineralogy has resulted due to source, sea-floor configuration, selective removal, reworking by different agencies and the processes operating in the ocean. There is no relation between a particular age and a set mineral assemblage for the Cenozoic sediments of the Indian Ocean.

Basalt analyses from different DSDP Holes in the Mozambique Basin and Ridge and from the Southwest Indian Ridge

Basalts from DSDP Sites 248, 249, 250 and 251 in the southwestern Indian Ocean formed in a complex tectonic region affected by the separation of Africa and South America. The different ages and variable geochemical features of these DSDP basalts probably reflect this tectonic complexity. For example, Site 251 on the flanks of the Southwest Indian Ridge is represented by normal MORB which probably originated at the Southwest Indian Ridge. Site 250 in the Mozambique Basin includes an older incompatible- element enriched unit which may represent basalt associated with the Prince Edward Fracture Zone; the upper unit is normal MORB. Basalts at Site 248 also in the Mozambique Basin are geochemically very unlike MORB and have strong continental affinities; they are also comparable in age to some of the continental Karroo basalts. They appear to be related to a subcontinental mantle source or to contamination by continental basement associated with the tectonic elevation of the Mozambique Ridge. Basalts from Site 249 on the Mozambique Ridge are relatively weathered but appear to be normal MORB. Their age, location, and composition are consistent with their origin at an early Cretaceous rift which has been postulated to have separated the Falkland Plateau from the Mozambique Ridge.

Na 1 Nachlass Max Horkheimer, 559 - Korrespondenzen mit Leo Löwenthal (p. VI 25, 1-248)

124 Briefe zwischen Leo Löwenthal und Max Horkheimer; 1 Brief von Leo Löwenthal an Theodor W. Adorno, 29.12.1954; 2 Briefe zwischen Max Horkheimer und Marjorie Fiske, 1954/1955; 2 Briefe zwischen Leo Löwenthal und Frederick Ungar, Oktober 1954; 2 Briefe zwischen Daniel Lerner und Leo Löwenthal, Oktober 1954; 3 Briefe zwischen Leo Löwenthal und Herbert Blumer, Oktober 1954; 1 Brief von Alice H. Maier an H. P. Edelman, 10.06.1954; 2 Briefe von Leo Löwenthal an The Trustes of Hermann Weil Memorial Foundation (New York), 27.04.1955; 1 Brief von Max Horkheimer an The Trustes of Hermann Weil Memorial Foundation (New York), Juni 1954; 4 Briefe zwischen Leo Löwenthal und Chauncy D. Harris, 1954/1955; 2 Briefe zwischen John I. Kirkpatrick und Leo Löwenthal, 1954; 3 Briefe zwischen Leo Löwenthal und R. Wendell Harrison, Mai 1954; 2 Briefe von Leo Löwenthal an Gustave E. von Grunebaum, 1954; 1 Brief von Leo Löwenthal an Morton Grodzins, 12.05.1954; 2 Briefe von Max Horkheimer an Charles Y. Glock, 1954; 1 Brief von Jeremiah Kaplan an Leo Löwenthal, 15.03.1954; 2 Briefe zwischen Leo Löwenthal und Max Rheinstein, März 1954; 1 Brief von Frederick Pollock an Max Rheinstein, [1954];