Resources Potential Evaluation Of Shale Gas In Paleogene Of Liaohe Depression In Bohai Bay Basin

The shale gas exploration in Liaohe is not yet mature.This paper studied three depressed areas(including Damintun depression,west depression,eastern depression),embarked on the organic-rich shale in the Es4&Es3.It not only has important theoretical value,but also play a strong role in promoting reality to speed up of shale gas resource potential of exploration and evaluation.Based on the development of shale geological setting and geochemical data,from shale's construction and sedimentary background,development characteristics in the vertical and horizontal,the type of organic matter,organic matter abundance,maturity of organic matter and mineral composition of rock,gas and other aspects of organic-rich shales in the Es4&Es3,this paper analyzed the characteristics systematically,selected some favorable areas,and estimated the amount of geological resources.Liaohe Depression in the Paleogene was ont only rifting peak period,but also the heyday of the basin development.In the time,it developed two sets of mud and shale system.Identified in the study area,organic-rich shale intervals through mud cores,logs and other methods,and found that the organic-rich shale in the Es3 was better than Es4,and organic-rich shale development focused on the sub-sections of the Es4 and under sub-section of the Es3.They are the favored choice for layers of shale oil and gas exploration.But its depth generally larger,over 3500 meters,is not conducive to the development of shale oil and gas.Though the analysis of the testing of shale organic geochemical parameters,it was found that types of organic-rich shale organic matter of Es4 were ?1-?2 and of Es3 were mainly ?-? 1 partial oil generation.Total organic carbon content was generally in the range of 1%to 3%,at the high maturity-over mature stage,and organic matter enriched in lower Es3 and upper Es4.Maturity of organic matter was generally low,higher only in the recessed area,and overall was in the oil generation stage,only part of the Health and wet-dry gas phase.Mineral content of brittle shale was High,average generally greater than 45%,with good potential to be fracturing.The main contributors to the brittleness are quartz,feldspar and other siliceous minerals,and carbonate content is small.Response characteristics by drilling,well testing and well-site analytical and experimental methods such as adsorption isotherm,it was found that in the study area two sets of organic-rich shale gas is good,and they far exceeds the minimum industry standards.The key parameters were stacked above a comprehensive analysis to obtain favorable area class ? resources,estimate the amount of resources and geology,obtained by Volume:The ? favorable areas of shale gas of Upper Es4 resources 0.037786 ×1012m3;Lower Es3 resources 0.43563 × 1012m3.