| The Surennuoer area is located in Beier lake depression of the Wuerxun depression in the Hailaer Basin,and has abundant hydrocarbon resources.However,due to the complex geological conditions,although the northern part already had the basic conditions for hydrocarbon accumulation,the proportion of developed reserves is low,the unused reserves are high,the favorable objectives are difficult to determine,and the progress of exploration and development is difficult.Therefore,it is necessary to study the main control factors of hydrocarbon accumulation in this area and determine the favorable target in order to further develop hydrocarbon.Based on the existing regional geological data,geochemistry data,seismic data,logging data,test data and oil test data,this paper systematically analyzes the hydrocarbon accumulation conditions in four aspects:supply condition,reservoir condition,caprock condition and trap condition,and combines the oil and gas distribution characteristics of each reservoir group in K1n,for studying the main control factors of hydrocarbon accumulation and the hydrocarbon accumulation patterns of K1n in Surennuoer area to achieve the goal of favorable selection.There are five main aspects in this thesis:1.there are 23 vertical supply paths of oil-source faults in different oil reservoir layer,mainly distributed near the Surennuoer tectonic belt and the southern depressions,and 29 lateral migration paths of sand bodies are mainly distributed in the Surennuoer tectonic belt and the middle of the study area,which converge to both sides of the Surennuoer fault and the east side of the study area as a whole.The reservoir of K1n is mainly delta sedimentary sand body,except that the sand body in the south of the study area is not connected,the sand body in other areas is connected,and the porosity is better.The caprock of the K1n is only not closed at the Surennuoer tectonic belt and part of the accompanying fault,and the rest of the caprock is vertically closed.The traps in K1n are mainly block traps,except a few in the south,the other traps are distributed in the northern and central areas of the study area.Because of the influence of sand body connectivity and fault lateral closure,the fault-fixed traps are mainly developed in the north-central region of the study area.2.there are reservoirs of fault anticline type,fault block type,fault nose type,fault occlusion type,fault-lithology type and lithologic type in K1n of Surennuoer area,mainly fault block oil and gas reservoir.The longitudinal distribution number of oil and gas wells in each layer is the most inⅡoil layer of K1n2,the second in oil formationⅠoil layer of K1n2,theⅠreservoir group in K1n1is relatively less.Oil and gas wells that have been drilled in the plane are mainly distributed around the Surennuoer fault belt,and few oil wells are found in the south.3.The hydrocarbon accumulation of K1n in Surennuoer area is mainly controlled by two factors:hydrocarbon supply condition and trap.The distribution area of hydrocarbon accumulation is mainly controlled by the vertical migration path of oil source fault and the lateral migration path of sand body,the oil and gas are mainly distributed in the range of 1.1 km from the oil-source fault and 1.5 km from the lateral migration path of the sand body.The trap controls the favorable position of hydrocarbon accumulation,but only the trap closed to the oil-source fault and the lateral migration path of sand body can be the effective trap,capture hydrocarbon and form oil and gas reservoir.4.The hydrocarbon accumulation model of K1n in Surennuoer area is the lower-born and upper-reservoir.As the main source rock strata of K1n1,the hydrocarbon formed by it during the hydrocarbon accumulation period migrated upward along the oil-source fault under the action of mechanics,Under the closed regional mud stone cover of the top in Damoguai River Formation,oil and gas conducts lateral transport in the reservoir of K1n1and K1n2,and finally accumulates into reservoir in the effective trap.5.There are 10 favorable targets for hydrocarbon accumulation in K1n of Surennuoer area,including 4 in K1n1and 6 in K1n2,which are mainly distributed near Surennuoer tectonic belt.The above research results can provide theoretical basis for the next oil and gas exploration of K1n in Surennuoer area. |
