12 resultados para Willis, Mattie
em Publishing Network for Geoscientific
Chemical Analyses of ferromanganese crust from the Alguhas Bank off South-Africa in the Indian Ocean
Resumo:
This synthesis dataset contains records of freshwater peat and lake sediments from continental shelves and coastal areas. Information included is site location (when available), thickness and description of terrestrial sediments as well as underlying and overlying sediments, dates (when available), and references.
Resumo:
Using spectrochemical techniques Fe, Si, Mg, Co, Ni, Cu, V, Mo, Ti and Tl have been estimated in nineteen manganese nodules, eight from the Atlantic ocean, seven from the Pacific ocean and four from the Indian ocean. Though data on more samples are required before firm and detailed conclusions can be made about the distribution of elements in manganese nodules, several distinct features appear when the data on the nineteen samples are examined. Certain elements appear to enrich more strongly than others. For example, relative to igneous rocks Mo is much more strongly enriched than V. For several elements (Ni, Cu and particularly Co and Tl) the degree of enrichment in two Fe-low nodules is far smaller than in the other nodules. The magnitude of dispersion of concentration appears to vary considerably for different elements; thus, whereas variation of concentration of V is relatively small, that of Ni, Cu, Co and Tl is far larger. The statistical nature of the distribution of Fe in manganese nodules appears to be characteristic and different from that of the other elements studied so far. Of the possible inter-element relationships examined that of Ni-Cu appears to be the most strongly developed.
Resumo:
Mn, Fe, Ca, Co, Ni, Cu, Zn, Cd, Sn, Tl, Pb and Bi have been estimated in thirty-two nodules from the Pacific, Atlantic and Indian oceans. Various features about the composition of manganese nodules are discussed: element abundances, degrees of enrichment, inter-element relationships (notably between Ni and Cu, and between Zn and Cd), regional variations and some aspects of statistical distribution.
Resumo:
During U.S. Department of Interior, Bureau of Land Management (BLM) public hearings held in 1973, 1974 and 1975 prior to Texas Outer Continental Shelf (OCS) oil and gas lease sales, concern was expressed by the National Marine Fisheries Service, scientists from Texas A&M and the University of Texas and private citizens over the possible environmental impact of oil and gas drilling and production operations on coral reefs and fishing banks in or adjacent to lease blocks to be sold. As a result, certain restrictive regulations concerning drilling operations in the vicinity of the well documented coral reefs and biostromal communities at the East and West Flower Gardens were established by BLM, and Signal Oil Company was required to provide a biological and geological baseline study of the less well known Stetson Bank before a drilling permit could be issued. Considering the almost total lack of knowledge of the geology and biotic communities associated with the South Texas OCS banks lying in or near lease blocks to be offered for sale in 1975, BLM contracted with Texas A&M University to provide the biological and geological baseline information required to facilitate judgments as to the extent and nature of restrictive regulations on drilling near these banks which might be required to insure their protection. In pursuit of this, scientists from Texas A&M University were to direct their attention toward assessments of ground fish populations, unique biological and geological features, substratum type and distribution, and the biotic and geologic relationships between these banks and those farther north.