FLUID INCLUSIONS: YESTERDAY, TODAY AND TOMORROW

Reviews in Mineralogy, Volume 12, FLUID INCLUSIONS, by Edwin Roedder is the only single-authored volume in the series. The volume, which was published in 1984, has sold over 6500 copies and is among the top-five selling volumes in the entire series. The scientific content of this volume, combined with the attention to presentation detail by Series Editor Paul Ribbe, has made this “the Bible” for fluid inclusionists world-wide, and it is still a valuable reference book 20 years after its initial publication.

Before about 1960, fluid inclusions were considered a curiosity by most mineralogists and were rarely studied to determine temperatures and pressures of mineral formation. Fluid inclusions had been used extensively by researchers in the Soviet Union before this, but these studies were limited by the available optical equipment and lack of PVTX data to interpret results of microthermometric analyses. Today, fluid inclusions are an accepted tool for determining the thermal evolution of geologic systems. In fact, fluid inclusions provide the most direct means of determining mineralization temperatures and pressures, and provide the only samples of mineralizing fluids that were present millions, or even billions, of years in the past. The most significant advance in fluid inclusion research during the two decades since publication of RIM 12 has been the development of analytical techniques that allow chemical analysis of individual fluid inclusions. These techniques, which include Raman, FTIR, PIXE, PIGE, and laser ablation ICPMS have significantly advanced our understanding of the chemistry and the role that fluids play in geologic systems.

In the future fluid inclusions will continue to provide valuable information concerning the evolution of hydrothermal systems. Current laser sampling techniques permit stable isotopic analysis of very large (>100 microns), individual fluid inclusions. As minimum sample size decreases and sampling techniques improve, it should become possible to determine the isotopic composition of more typical (several 10s of microns) inclusions. Similarly, improvements in sampling and increased sensitivity of analytical techniques for radiogenic isotopes should permit ages of individual fluid inclusions, and thus fluid events, to be determined.