Interpretation Of Tight Oil Horizontal Wells In Qanan Area

With the long-term development of conventional oil and gas resources,the technical difficulties and economic costs of conventional oil and gas exploitation have increased.Unconventional oil and gas has become the focus of future oil and gas exploitation.The exploration and development of compact oil is another new hotspot of global unconventional oil and gas exploration and development after shale gas.According to the initial results of industrial exploitation of Elmcoulee Bakken Formation in Williston Basin,American oil has been produced.The world energy pattern has been changed by the increased of exploitation to a certain extent.Comparing with foreign countries,China is rich in dense oil and gas resources.Some important exploration discoveries have been made in the technical pages of exploration and development,which have great potential for China's important oil replacement resources in the future.Generally,the exploitation of tight oil is fracturing before water flooding.TOC with total organic matter content is difficult to form a continuous conclusion because of its high cost of coring,which brings inconvenience to the evaluation of hydrocarbon source rock abundance,and it is difficult to guide the exploration and development of tight oil accurately and effectively,and brings difficulties to unconventional oil and gas exploitation.Quan4 reservoir of Fuxin uplift in southern Songliao Basin is a source reservoir,located in Changling sag of Songliao Basin.The reservoir has abundant reserves with an area of 4600 km2 and a reserve scale of 500 million tons.The proved reserves account for more than 50%of the total reserves.Most of the horizontal wells are concentrated in thin reservoirs with ultra-low porosity and permeability,and most of the reservoirs have poor physical properties.In addition to conventional oil,Qian'an area of Jilin Oilfield will focus on exploration and development of tight oil in the near future.This paper collects and collates the data of horizontal and vertical well logging and oil testing in Qian'an area.Through logging evaluation of reservoir parameters of horizontal wells in Qian'an area,such as shale content,porosity,permeability,irreducible water saturation,residual oil saturation and water saturation,the interpretation model is established,the reservoir types are divided,the identification criteria of oil and water layers are established,the oil and water layers are compared,and the oil and water layers are identified.The standard compliance rate was 91.4%.Using the horizontal well logging interpretation software(DIPLOG),the two-dimensional interpretation mapping of horizontal well and its guide hole or adjacent wells is carried out.The baseline section is selected to obtain the logging parameters of the baseline section.The improved TOC model of three-para meter tight oil is established.Compared with the classical LogR model,the improved TOC content model has higher accuracy and the error is reduced by nearly 5%compared with LogR model.Reservoirs are divided into 10 wells and 110 formations,which are divided into four types aceording to TOC eontent.The relationship between TOC content and logging parameters is studied.It is found that the saturation and hydrocarbon expulsion distance are negatively correlated with pore structure in reservoirs with different TOC content.By comparing and analyzing the oil saturation of 41 reservoirs in three wells calculated by Archie for mula,it i5 found that the oil saturation of most horizontal sections is within the allowable error range,the error of oil saturation calculated by hydrocarbon expulsion distance H is 1.28%,and the error of oil saturation calculated by pore index isl.34%.It can be used to guide the exploration and development of tight oil and plays an important role in unconventional oil and gas development.