APPROACHING TO CHEMICAL COMPOSITION AND APPLICATION OF RAMAN SPECTRUM OF FLUID INCLUSION——TAKING THE LOWER ORDOVICIAN RESERVOIRS IN TAHE AS AN EXAMPLE

Based on the studies of chemical composition and features of Raman spectrum(LRM),together with the relationship between the displacement values(ν) of the major chemical composition CO₂,CH₄,H₂O and the buried depth of fluid inclusion.the author has shown that: 1)It can be proposed that there are at least eight types and four assemblages inclusions occurred in the Lower Ordovician reservoirs;2) The richness of CO₂-,CH₄-hydrocarbon and H₂O-CO₂ brine inclusion are dominant in those assemblages;3) In a single inclusion,the content of methane in gas phase increase initially but decreases at later with increasing that of depth;4) The displacement value(ν) and content of methane simultaneously decrease with the buried depth of samples;5) The displacement value(ν) of water presents a non-line covariance with the depth of samples;6) The contents of methane in gas phase demonstrated a negative linear covariance of its contents carbon dioxide;and the author believed that those parameters can be used as the indicator of maturity of hydrocarbon emplacement.