The Characteristics And Genesis Of Salt Minerals From The Fengcheng Formation In Urho Area, Junggar Basin

Hydrothermal sedimentary has been the frontier aspect and research hotspot of geology all over the world, research reports for lacustrine facies hydrothermal sedimentary rock relatively less within home and abroad. The tight oil reservoir of Fengcheng formation in Urho Area is a set of very special lacustrine dead color fine salt-bearing volcano sedimentary formation, and lithology is deep lacustrine facies dolomitic rock types in which rich in salt minerals, early research thinks that belong to relatively rare sublacustrine hydrothermal jet flow sedimentary genesis. The deep lake sedimentary formations in the development of a large number of salt minerals such as Dolomite, Ankerite, Reedmergnerite, Shortite, Nahcolite, Halite, Anhydrite, etc. Caused great concern in the author’s team, but rarely mentioned in the previous research.In this paper, full investigation previous research results about salt minerals of marine\lacustrine, evaporation\hydrothermal genesis, sedimentology, petrology, mineralogy, reservoir geology and geochemistry and other disciplines theory as a guide, the deep study of Fengcheng Formation salt minerals in study area are researched in detail by the means of drilling core observation, thin section identification, scanning electron microscope, X-ray diffraction, electron microprobe, isotope, trace element, rare earth elements, fluid inclusion microthermometry and laser Raman analysis methods and techniques.By analyzing the regional tectonic setting, sedimentary environment, petrological and mineralogical characteristics of the study area, obtained the characteristics of salt minerals, and demonstrate salt minerals from Fengcheng Formation in study area are different from modern evaporation salt lake deposition salt minerals, shows the particularity. By analyzing geochemical characteristics obtained the properties and sources of minerogenic fluid, and demonstrate sedimentary environments of salt minerals belong to a environment of relatively closed, reduction, intermittent and mixed deep lake waters. On the basis of this analysis, obtained the genetic types of salt minerals, and establish a double diffusion convection salt formation mode of deep hydrothermal solution of endogenous and exogenous causes of lacustrine salt minerals from Fengcheng Formation in study area.