The Oxidation-Reduction Potential in Geology

ISBN-13: 9781468415957 / Angielski / Miękka / 2012 / 122 str.

M. F. Stashchuk; M. F. Stashchuk

Opis

Within very recent time, when investigating the allowing one to explain possible transformations according to variations in different characteristics physicochemical conditions under which sedimen tary rocks formed, geologists were satisfied with of the environment. logical premises prompted by sound judgment. The present book is written within the indicat ed framework. I am pleased that this book, in which Recognizing the great role of this factor in develop ment of the science, it is still necessary to keep in the graphical method is used and popularized, has mind that sound judgment based on impressions and been translated into English. subjective experience of the observer does not al In giving a physicochemical evaluation of ways bring us to an understanding of objective existing methods for determining the oxidation reduction conditions under which sedimentary rocks reality. Probably greater success in explaining the form, I have tried to present the material in such a way that the warning against too formal an applica physicochemical features of the environment in which sediments accumulate may be achieved by tion of thermodynamics is obvious."

Spis treści

1 The Principal Methods of Determining Oxidation — Reduction Conditions.- The Fe../Fe… Ratio and Eh.- The Forms of Sulfur as Indicators of Oxidation — Reduction Conditions.- The Relationship of Organic Matter in Sediments and the Oxidation — Reduction Potential.- Iron-Mineral Indicators of Oxidation — Reduction Conditions.- Garrels’ Thermodynamic Diagrams.- Other Methods of Determining Oxidation-Reduction Conditions.- 2 Thermodynamic Principles for Investigating the Conditions of Mineral Formation.- The Solubility of Compounds and the Maximum Work of a Reaction.- The Concept of the Oxidation-Reduction Potential.- Analysis of Some Errors.- 3 Stability Diagrams of Iron Minerals.- Stability Boundary of the Natural Environment.- The System Fe(OH)3-Fe3O4-Fe(OH)2.- The System Fe(OH)3-Fe3O4-Fe(OH)2 + CO2.- The Appearance and Behavior of Sulfide Ions in Sediments.- Mineral Forms of Iron Sulfides in Sedimentary Rocks and Recent Sediments.- Stability Diagrams of Sulfides.- 4 Conditions for Formation of Iron Minerals during Sedimentation and Diagenesis.- Change of pH during the Diagenesis of Sediments.- Change of Oxidation — Reduction Potential during Diagenesis of Sediments.- The Distribution of Hydrogen Sulfide.- Analysis of Mineral Formation.- Indicators of Oxidation — Reduction Conditions under Which Sedimentary Rocks Form.- Conclusions.- Literature Cited.