Coal reservoirs have strong heterogeneity,andin-situ stress has an important influence on coaldeformation and productivity.In this paper,thefactor analysis method is used to construct a coalreservoir in-situ stress calculation model based on alarge number of coal reservoirs' microscopic com-position,coal quality,fracturing,and logging data.The research results show that the coal ranks of thestudied coal reservoirs are relatively high,mainlylean coal-anthracite.The conventional loggingresponse curve of coal seam is obviously differentfrom that of roof and floor sand and mudstone.It ischaracterized by three lows and three highs,name-ly,low gamma (GR),low spontaneous potential(SP),low density (DEN),and high longitudinalwave time difference (AC),high compensationneutron(CNL) and high resistivity (deep lateralresistivity RD and shallow lateral resistivity RS)features.The stress state of the coal seam calculatedby the fracturing method satisfies: horizontal mini-mum principal stress (oh) 展开▼
