Isotope geochemistry has grown over the last 60 years to become one of the most important fields in the earth sciences. It has two broad subdivisions, namely, radiogenic isotope geochemistry and stable isotope geochemistry. These subdivisions reflect the two primary reasons why the relative abundances of isotopes of elements vary in nature, which are radioactive decay and chemical fractionation; in this context, “fractionation” is any process in which the isotopes of the same element behave differently.

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

The Mediterranean Sea lies between Europe, Asia and Africa in an area famous for its ancient civilizations and cultural developments. It was an area where marine navigation was developed and where many trade routes intersected. The publication of one of the first monographs on marine geology and geography by Marsilli in 1725 suggests that the Mediterranean Sea was the cradle of marine geology.

It is known that methane (and, in smaller amounts, higher hydrocarbons) is liberated during the coalification process. The amounts of methane developed vary in the different stages of coalification. Calculations on the basis of ultimate analyses of coals of different rank done by Mott (1943), Patteisky(1952, 1964) and Jüntgen and Karweil (1966) lead to the conclusion that greater amounts of methane start to be developed when the stage of bituminous coals with about 30% of volatile matter (dry and ash-free) is reached, whereas the gas developed from lignite and less metamorphosed bituminous coals is mainly carbon dioxide.

This book is about geochemical data and how they can be used to obtain information about geological processes. Conventionally geochemical data are subdivided into four main categories: the major elements, trace elements, radiogenic isotopes and stable isotopes (see Table 1.1 ). These four types of geochemical data each form the subject of a chapter of this book. Each chapter shows how the particular form of geochemical data can be used and how it provides clues to the origin of the suite of rocks in question. Different methods of data presentation are discussed and their relative merits evaluated. <...>

Геохимические особенности осадочных пород всегда несут ту или иную информацию о происхождении этих пород - и не только о фациях седиментогенеза (как это мыслилось на заре исследований в 1960-70-е гг.), но и в более общем смысле - о процессах литогенеза в широком понимании этого термина, т.е. включая процессы выветривания, мобилизации, переноса, седиментации, диагенеза, катагенеза и, наконец, - рециклизации. Поэтому собранный и систематизированный в этой книге огромный материал не только дает подробную характеристику геохимических (а также минеральных и органических) индикаторов литогенеза, но и является, в сущности,

Isotopes originated with the emergence of elements in the Universe during the first infinitesimal fraction of a second following the postulated Big Bang now generally accepted as having started the dynamic expansion observed today.l Some remarks concerning this seminal event are in order.

Выявлены окислительно-восстановительные состояния элементов, при которых они занимают максимальные и минимальные позиции. Элементы в таких экстремальных состояниях образуют четыре периодичности (две — максимумов и две — минимумов), одна из которых является Менделеевской. Они координируются в общую систему рядами неэкстремальных элементов. Система представляет новую основу для геохимических обобщений и ныя’вления условий образования парагенезисов элементов, при которых происходит их совместная концентрация в процессах минерало-образования.
Представляет интерес для геохимиков, петрографов, минералогов и кристаллохимиков.

The continually rising standards of petroleum geoscience and oil search require an ever greater knowledge of the fundamental nature of petroleum, its origin, and its behavior in the rocks of the earth’s crust. In the early stages of the petroleum era, most oil men were not much concerned about the how, why, and when of oil and gas; all they cared to know was where. Those years are gone, and it is now more and more recognized that the how, why, and when of petroleum are critical keys to where it should be sought.