Geochemical barrier zones play an important role in determining various physical systems and characteristics of the oceans, e.g. hydrodynamics, salinity, temperature and light. In this book, each of the 40 barrier zones covered are illustrated and defined by physical-chemical parameters. Among the topics discussed are the processes of inflow, transformation and precipitation of the sedimentary layer of the open oceans and more restricted areas such as the Baltic, Black and Mediterranean Seas. This well-illustrated book may serve as the basis for courses such as "Marine Geochemistry" or "Ocean Usage" and can be useful to researchers in the fields of geology, geography, marine chemistry, geoecology and hydrochemistry.

The monograph presented to foreign readers has been prepared by the famous Soviet investigators of processes of geochemistry and sedimentation in the Mediterranean Sea. For more than 20 years E.M. Emelyanov has examined the recent sedimentation of the Mediterranean Sea and K.M. Shimkus has studied the Quaternary and the earlier sedi mentation of the area. The authors, scientific workers from the P.P. Shirshov Institute of Oceanology, USSR Academy of Sciences (Atlantic and Southern Depart ments), took part not only in numerous cruises on oceanographic vessels of the USSR, but in the study of cores of the deep-sea drilling on R/V "Glomar Challenger." A great number of scientific papers and some books devoted to the processes of sedimentation and geochemistry of the Mediterranean Sea were written by them. Although the scientific interests of the authors are not only limited to these questions, I should like to emphasise these aspects of their scientific activity when introducing this book. The Mediterranean Sea is a suitable natural laboratory for solving a number of principal problems of marine sedimentation and lithogenesis."

The monograph presented to foreign readers has been prepared by the famous Soviet investigators of processes of geochemistry and sedimentation in the Mediterranean Sea. For more than 20 years E.M. Emelyanov has examined the recent sedimentation of the Mediterranean Sea and K.M. Shimkus has studied the Quaternary and the earlier sedi mentation of the area. The authors, scientific workers from the P.P. Shirshov Institute of Oceanology, USSR Academy of Sciences (Atlantic and Southern Depart ments), took part not only in numerous cruises on oceanographic vessels of the USSR, but in the study of cores of the deep-sea drilling on R/V "Glomar Challenger." A great number of scientific papers and some books devoted to the processes of sedimentation and geochemistry of the Mediterranean Sea were written by them. Although the scientific interests of the authors are not only limited to these questions, I should like to emphasise these aspects of their scientific activity when introducing this book. The Mediterranean Sea is a suitable natural laboratory for solving a number of principal problems of marine sedimentation and lithogenesis."

Geochemical barrier zones play an important role in determining various physical systems and characteristics of the oceans, e.g. hydrodynamics, salinity, temperature and light. In this book, each of the 40 barrier zones covered are illustrated and defined by physical-chemical parameters. Among the topics discussed are the processes of inflow, transformation and precipitation of the sedimentary layer of the open oceans and more restricted areas such as the Baltic, Black and Mediterranean Seas. This well-illustrated book may serve as the basis for courses such as "Marine Geochemistry" or "Ocean Usage" and can be useful to researchers in the fields of geology, geography, marine chemistry, geoecology and hydrochemistry.