Tectonic hydrothermal dolomite and its significance of reservoirs in Tarim basin

The outcrop and core data show that there have developed wide distribution of tectonic hydrothermal dolomitization of Lower Palaeozoic in Tarim basin.This kind of dolomitization have its special characteristics from petrology and geochemistry,and marked as saddle dolomite and euhedral dolomite,existing as coarse grain structure in cracks and holes with the high homogenization temperature and salinity from fluid inclusions and the lighter carbon and oxygen isotope values which has a range of overlapping with around rocks on geochemistry,while Sr isotopes is not obvious and showing features from their origin rocks.There have obvious difference with Devonian hydrothermal dolomite in Seaga basin.The extensive development of the Permian magmatic thermal event of Tarim basin maybe is the main causes of tectonic hydrothermal dolomite.The reservoir related to tectonic hydrothermal dolomite are mostly high-quality reservoir,which distribution are closely related to fracture and unconformity,will be a favorable target for oil and gas exploration.