A broad west-to-east increase of many metal concentrations has been found in stream sediments during a reconnaissance investigation conducted in conjunction with geologic studies in the Santa Renia Fields and Beaver Peak 7–1/2 minute quadrangles near the northern end of the Carlin trend of gold deposits in the Tuscarora Mountains. This regional increase in metal concentrations coincides with a dramatic change in landform wherein high concentrations of metals in stream sediments appear to correlate directly with areas of high elevations and steep slopes in the Beaver Peak quadrangle. Robust erosion combined with high flow rates in streams from these higher elevations are envisaged to have contributed significantly to increased metal concentrations in the stream sediments by an enhanced presence of minerals with high specific gravities and a correspondingly diminished presence of minerals with low specific gravities. Minerals with low specific gravities probably have been referentially flushed down stream because of high transporting capacities for sediment by streams in the Beaver Peak quadrangle. In addition, the Carlin trend, a generally northwest-alignment of gold deposits in the Santa Renia Fields quadrangle, is well outlined by arsenic concentrations that include a maximum of approximately 54 parts per million. Further, a weakly developed distal-to-proximal metal zonation towards these gold deposits appears to be defined respectively in plots showing distributions of thallium, arsenic, antimony, and zinc. A broad area of high metal concentrations—including sharply elevated abundances of Ag, As, Au, Cd, Co, Cu, Mn, Ni, P, Sb, Sc, Te, V, and especially Zn—near the southeast corner of the Beaver Peak quadrangle primarily could be the result of stratiform mineralized rocks in the Ordovician Vinini Formation or Devonian Slaven Chert, or the result of a subsequent Mesozoic or Tertiary epigenetic overprint. <...>

Chapter 1 Geochemical and Sedimentation History of Neogene Lacustrine Sediments from the Valjevo-Mionica Basin (Serbia)
Aleksandra Šajnović, Ksenija Stojanović, Vladimir Simić and Branimir Jovančićević
Chapter 2 Arsenic Geochemistry in Groundwater System
Dionisios Panagiotaras, George Panagopoulos, Dimitrios Papoulis and Pavlos Avramidis

Chapter 3 Geochemistry of Hydrothermal Alteration in Volcanic Rocks
Silvina Marfil and Pedro Maiza

Geochemistry utilizes the principles of chemistry to explain the mechanisms regulating the workings – past and present – of the major geological systems such as the Earth’s mantle, its crust, its oceans, and its atmosphere. Geochemistry only really came of age as a science in the 1950s, when it was able to provide geologists with the means to analyze chemical elements or to determine the abundances of isotopes, and more significantly still when geologists, chemists, and physicists managed to bridge the chasms of mutual ignorance that had separated their various fields of inquiry.

The modern geologist with no knowledge of geochemistry will be severely limited. Indeed, geochemistry now pervades the discipline—providing the basis for measurement of geologic time, allowing critical insights into the Earth’s inaccessible interior, aiding in the exploration for economic resources, understanding how we are altering our environment, and unraveling the complex workings of geochemical systems on the Earth and its neighboring planets. Geochemical reasoning reveals both processes and pathways, as the book’s title implies.