Discriminate method of coal structure based on correspondence analysis technology:A case study in the Anze area,Qinshui Basin

To better understand the effect of coal structure on CBM exploitation,the plane distribution and vertical vari- ation of coal structure were accurately acquired. Using six kinds of logging data from 88 coal coring samples in 13 ex- ploration wells,the coal coring samples were systematically and quantitatively divided by using correspondence analysis technology,which showed that the core samples of different coal structures acquired from core logging data clustered together in the corresponding analysis map obtained from correspondence analysis (the matching rate of the classifica- tion coal coring samples divided by using correspondence analysis and coal structure acquired from core logging data was 97. 7% ). Based on the result from corresponding analysis,the coal structure of the remaining CBM wells can be evaluated. Therefore the coal structure distribution of the Anze area can be acquired. The coal structures were evalua- ted:vertically,undeformed coals in the top and bottom,cataclastic coals positioned between the undeformed and granu- lated coals,and granulated coals located in the middle;horizontally,furthermore,the undeformed coals and cataclastic coals are located in the northern and near An12 in the southern parts of the study area (area Ⅰ);the granulated coals are mainly near the well An28 and An22 in the southern and near the fault F1 and fault F2 in the south-central parts of the study area (area Ⅱ);Reservoir condition of area Ⅰ is more favorable than area Ⅰ in southern and south-cen- tral area.