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The Huadian shale gas blocks in Western areas of Huan-Hubei includes Hefeng,Laifeng-Xianfeng,Yongshun and Huayuan blocks with total areages of 4058km2,the geotectonic position of four blocks located on western areas of Hunan-Hubei fold thrust belt of Yangtze plate,and which has undergone several tectonic movements.In early stage of early Cambrian,a set of deep-shallow shelf clastic rocks were deposited with a large scale transgression in Sichuan,Chongqing,Hunan and Hubei areas.After Middle Ordovician,with the compression of the Yangze block,the western areas of Hunan-Hubei continuous subsided and a flow retarding stillwater basin formed,and lead to a set of grey black carbon-bearing shales of lower Longmaxi Formation were deposited.Because of the complicated tectonic changes with the characteristics of high amplitude uplifting and large scale compression,the Lower Paleozoic shales is serious in deformation,strong in destruction and distributed mainly as high dipping folds.The study showed that it had favorable conditions for shale gas accumulation in western areas of Hunan-Hubei.The Lower Cambrian Niutitang shale distributed widely in whole areas and its depth ranged from 1500 to 6000m.The burial depth has largest in Hefeng Block with the maximum depth of 8000m and lower depth in Huayuan Block with the maximum depth of 3000m.The overall thickness of the shale formation more than 100m in the four blocks.The TOC value in most areas is over 2.0% and the largest value is 14.64%.The thermal maturity which measured with Ro ranges from 2.5% to 3.5% and it reaches dry gas zone.Through shale gas favored intervals selection,the thickness of shale gas with TOC>2.0% ranges from 60m to 120m.The Longmaxi shale of Lower Silurian was eroded in certain areas due to the Guangxi Movement.The Longmaxi shale was all eroded in Huayuan Block,the distribution in other three blocks is 2053km2,and the depth is less than 3000m.The Longmaxi shale in Hefeng Block is deeper with maximum depth is over 5000m and the thickness is 20-80m.The TOC values range from 1.4% to 5.0% and the shale thickness with TOC>2.0% is 10-35m.The Ro is between 2.35% and 3.10% and it belongs to the dry gas zones.Through analysis of Rocks and Minerals,the brittle minerals content of Niutitang and Longmaxi shales are both relatively high,the quartz and feldspar content of Niutitang shale is 47%-88%,longmaxi shale is 44%-77%,and high angle microfractures were found in Changye 1 well and Yongye 1 well,and those characteristics showed that brittle fractures easily be produced in Niutitang and Longmaxi shales.Considering the shales burial depth,thickness,TOC value and the distribution of faults,a multiple factors analysis were used to selecting favorable areas,Niutitang shales have 7 favorable areas and the most favorable ones distributed in Bayan syncline areas of Huayuan block,Lonamgxi shales have 1 favorable area and distributed in Lianghekou syncline core of Laifeng-Xianfeng block.