THE PRECISE SURVEY TECHNIQUE OF GEOCHEMICAL EXPLORATION IN THE OIL FIELD'S EXPLORATION AND DEVELOPMENT

The precise survey technique of geochemical exploration is a new technique that recently developed for oil field's exploration. In the basis of knowing the rules of regional geochemistry,studying the characteristics of near surface geochemical effect in discovered field,knowledge about the stratum and liquid's chemical property in different periods were obtained. In the mean time,with the help of high density regulation surveying web various methods were applied to detect the components of reservoirs and the vertical micro-migration traces of the oil and gas. These methods respectively use synthetic hydrocarbon gas(dissociate hydrocarbon, adsorptive hydrocarbon, subsistent hydrocarbon, water-dissolved hydrocarbon, high-carbon hydrocarbon), light aromatic hydrocarbon and isotope. In data processing,polybasic statistics and geological statistics were combined to acquire information in concentration lining degree,structure,fabric and analogism. At the same time,anomalous boundary was determined by simulation and the quantitative evaluation method for geochemical exploration anomalies was also discussed. The precise survey technique can specify the range of oil field, give the extension direction of discovered oil fields and provide the scientific basis for drilling production wells and exploration wells.