Inorganic Geochemical Techniques
Part I of this manual describes inorganic geochemical techniques that can be used to deduce the origin of a dolomite and establishes guidelines that geologists can follow to interpret dolomite geochemical data.
Our specific goal in studying dolomitization is to gain a better understanding of the factors that control a dolomite unit's extent and shape — to determine whether it is stratiform, structurally controlled, etc. The geochemical techniques that are most useful in attaining this goal are:
Produced formation water analyses
Oxygen and hydrogen isotopic compositions
Oxygen and carbon isotopic compositions
Fluid inclusion homogenization temperatures and salinities
Strontium isotopic compositions
Trace element concentrations (particularly Fe and Mn)
The analytical techniques in (1.) shed light on whether dolomite has formed from present-day well or formation fluids. When analyzing a produced formation water, relevant questions one might ask are: “Did this water originate as expelled interstitial evaporite brine, invaded meteoric water, or seawater?”; and “Was the water ever involved in dolomitizing limestone?”
The analytical techniques in (2.) shed light on the physical and chemical environment in which a dolomite formed. When analyzing dolomite, relevant questions one might ask include: “At what temperature and depth did dolomitization occur?”; “What was the salinity of the fluid responsible for dolomitization?”; and “To what extent did organic matter maturation and degradation products and siliciclastic diagenesis contribute to
Figures & Tables
Dolomite Reservoirs: Geochemical Techniques for Evaluating Origin and Distribution was written to address the need for a short, clear text that explains commonly used inorganic geochemical techniques and their application to dolomite petroleum reservoirs. This volume contains two parts. Part I consists of chapters on different geochemical techniques, with guidelines on how best to apply them, interpret the data, and recognize and avoid the pitfalls and misconceptions that are commonly encountered. Part II consists of case studies of dolomite petroleum reservoirs that formed in each of the major dolomitization environments. This publication will help geoscientists better understand the many ways in which geochemistry can be used to address dolomite reservoir problems.