Isotopic Application in High Saline Conditions

Abstract

Evaporite minerals record the hydrogeochemical conditions in which they precipitated. And therefore they can be used to reconstruct the paleoclimate and paleoenvironments. Evaporite minerals are also major sources of industrial minerals including gypsum, halite, borates, lithium concentrates, and others. Because of their scientific significance and economic importance, evaporite minerals and their isotopic hydrochemical processes linked to their formation have been the focus of many geologists and paleoclimatologists. This chapter will discuss the application of isotopes of hydrogen, oxygen, sulfur, strontium, and boron in saline conditions. This will include the following: the δ 18 O and δ D of hydrated water of gypsum and their paleoclimate since 2.2 Ma in the Qaidam Basin, NE Tibetan Plateau; the δ 18 O and δ D of the interlayer water of clay minerals in salar lacustrine sediments; and the 87 Sr/ 86 Sr, δ 34 S, and δ 11 B of halite from evaporite deposits in Khorat Plateau, Laos, and Yunnan and their application in the origins of brine.