The Characteristic Of The Reservoir And Favorable Area Prediction In The Chang 10₁ Oil-bearing Bed In The Ansai Oil Field, Ordos Basin

Ansai area is located in Shanbei slope of Ordos Basin. According to the characters of lithology, electricity and oilness, the Chang 10 oil-bearing bed is subdivided into Chang 1011, Chang 1012, Chang 1013,Chang102and Chang 103.According to the analysis of the fades marks, such as lithology, sedimentary structure, fossils, logging facies and other marks in the study area, the analysis of the facies shows that the Chang 10 oil-bearing bed is delta plain. The main sedimentary microfacies is distributary channel.Feldspathic sandstones and debris feldspathic sandstones are the mainly reservoir sandstone of Chang 10 oil-bearing bed in the study area. The porosity is mainly the kind of intergranular pore and lomontite dissolved pore. Compare the geochemistry characteristics of Chang 10 crude oil and Chang 7,Chang 9 dark mudstone, according to the relation of biomarkers and inclusions distribution characteristics, consider that Chang 10 oil sources is Chang 9 source rock.Chang 10 oil poor is in controlled of many factors. The development of Chang 10 oil poor is in controlled of the source rock. Overpressure is the main power of Chang 10 oil-gas migration. Fracture gives the way of the oil-gas migration. The main types of Chang 10 oil poor are structure-lithological oil poor and lithological oil poor.On the base of the above research, used the favorable sedimentary microfacies sand body characteristic, property characteristic and oil test results and other parameters, predicted and evaluated Chang 1011 and Chang 1012 reservoir sand bodies, we were selected 1 practical construction area,4 potential exploration areas and 2 vision areas.