The stable isotope and minor element geochemistry of Neocomian (Lower Cretaceous) pelagic carbonates of the North Atlantic Basin (Deep Sea Drilling Project Sites 105, 367, 387, 391, and 603) was examined to develop a diagenetic model for pelagic limestones. In particular, we hoped to test the fidelity of whole-rock geochemical records as paleoceanographic indicators for pelagic deposits of pre-...

A fundamental challenge in modern mantle geochemistry is to link geochemical data with geological and geophysical observations. Most of the early geochemical models involved a layered mantle and the concept of geochemical reservoirs. Indeed, the two layer mantle model has been implicit in almost all geochemical literature and the provenance of oceanic island basalt (OIB) and mid-ocean ridge bas...

The surface geochemical response to bedrock containing elevated levels of the platinum group elements (PGE) is commonly so subtle that standard geochemical methods are insufficiently sensitive to assist the exploration geologist. At the Geological Survey of Canada, recent research on analytical methods by one of us (GEMH) has been directed toward the development of a selective leach of soils an...

Introduction Volcanism on Venus has produced a rich array of volcanic landforms [1], which in turn suggests a broad range of magma production and differentiation environments. In the next decade, it is possible that one or more landers associated with New Frontiers or Flagship class missions to Venus will provide new geochemical observations of the Venus surface. The goal of this work is to mak...

Contamination of groundwater by naturally occurring arsenic has recently become a disturbing environmental problem in Viterbo area, Central Italy. Arsenic concentrations in most of the public supply networks exceed the maximum allowable limit of 10 μg/l (WHO) for drinking water. The primary purpose of this paper is to obtain a better understanding of the factors contributing to the high levels ...

Microorganisms have contributed significantly to subsurface energy resources by converting organic matter in hydrocarbon reservoirs into methane, the main component of natural gas. In this study, we consider environmental controls on microbial populations in coal-bearing strata of the Cherokee basin, an unconventional natural gas resource in southeast Kansas, USA. Pennsylvanian-age strata in th...

sediments are generally regarded as the sink for dissolved elements carried out to the sea by rivers. in order to study the source and mechanism of metal transport in sea water, 123 surface sediment samples were taken by using grab sampler in the northwest part of the persian gulf in summer. grain size analysis and geochemical analysis by icp-oes were carried out on samples after sample prepara...