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Geology topics

C.W. Dick

Publications and source records attributed to C.W. Dick.

2 recordsLinked to original sources

Trans-Amazon Drilling Project (TADP): origins and evolution of the forests, climate, and hydrology of the South American tropics

This article presents the scientific rationale for an ambitious ICDP drilling project to continuously sample Late Cretaceous to modern sediment in four different sedimentary basins that transect the equatorial Amazon of Brazil, from the Andean foreland to the Atlantic Ocean. The goals of this project are to document the evolution of plant biodiversity in the Amazon forests and to relate biotic diversification to changes in the physical environment, including climate, tectonism, and the surface landscape. These goals require long sedimentary records from each of the major sedimentary basins across the heart of the Brazilian Amazon, which can only be obtained by drilling because of the scarcity of Cenozoic outcrops. The proposed drilling will provide the first long, nearly continuous regional records of the Cenozoic history of the forests, their plant diversity, and the associated changes in climate and environment. It also will address fundamental questions about landscape evolution, including the history of Andean uplift and erosion as recorded in Andean foreland basins and the development of west-to-east hydrologic continuity between the Andes, the Amazon lowlands, and the equatorial Atlantic. Because many modern rivers of the Amazon basin flow along the major axes of the old sedimentary basins, we plan to locate drill sites on the margin of large rivers and to access the targeted drill sites by navigation along these rivers.

Amazon region

Ovarian fluid: Its role in fertilization

FISH-CULTURISTs, in general, do not agree as to the time of actual fertilization of artificially spawned salmonid eggs. Some fish-culturists believe that the eggs are fertilized in the milt before water is added, while others are equally certain that fertilization is not achieved until after water is added. This difference of opinion has probably existed since the advent of the dry spawning method, in which milt is added to the eggs without the presence of water in the spawning pan. According to the "Manual of Fish-Culture" published by the U. S. Commission of Fish and Fisheries in 1900, it was known that eggs and milt from salmon maintain their viability for many hours if held in open containers, that both eggs and milt soon lose their viability when water is added, and that the milt and fluid around the eggs can be "utilized in impregnating masses of eggs when there is a scarcity of males, as sometimes occurs toward the close of the spawning season." The object of the studies reported here was to confirm some of the foregoing observations and to determine whether salmonid eggs could be fertilized without the supportive action of water.

Progressive Fish-Culturist