Middle-Upper Frasnian clastic-carbonate sequence is the new prospect on the Northern margin of Pre-Caspian depression. Kolgan unit, quite well explored in Orenburg region, could be thought of as its analog. In Kazakhstan interest to this subject had appeared after oil discovered on Chinarevskoye field. Frasnian clastic-carbonate sequence has the limited areal distribution which is because of specific sedimentological environment. Lithotypes were described in both carbonate and clastic parts, facial zonation identified, detail lithological and petrophysical characteristics given and sedimentological model proposed based on regional data, well log interpretation and core study from three wells drilled in the Northern part of Chinarevskoye field. In the result of well testing it’s found that the reservoirs are practically absent in the carbonate part therefore the main attention is paid to identification the reservoirs association with the clastic faces. Based on petrophysical parameters of different Frasnian clastic lithotypes it’s possible to conclude that in the Northern part of Chinarevskoye field the fans proximal part as well as distributary are the most promising facies for reservoir formation. Seism facies and attribute analysis of 3D seismic calibrated on the well data was used for forecasting subsurface geology in interwell space and outline zones with maximum sands in the section. Sand bodies geometry obtained from the different maps is consistent with proposed sedimentological model.
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