Luacustrine mudstone and sapropel coal in the middle Permian and the low Jurassic as well as cannel boghead in the middle and upper Triassic have abundant exinoid group and saprepel group, they have highest hydrocarbon-generating potentiality in the basin, while humic coal distributed in the middle and lower Jurassic has abundant vitrinite and inertrinite which has poor liquid hydrocarbon genera.

the study combined both coal petrologic and geochemical methods indicated that the sclerotia algal coal is physically and chemically different from humic coal apparently,the forming environment is mainly controlled by pH,Eh and organic content,in which Pila Alginite and Reinschia Alginite are highly dominated.

The karstic fracture water C6 exit point in underground +335m main roadway of Songzao coalmine,because of it takes in recharging from surface catch-pit,so the maximum inflow of 3500m3/h from the point composed huge threaten to mine safety.

The karstic fracture water C6 exit point in underground +335m main roadway of Songzao coalmine,because of ittakes in recharging from surface catch-pit,so the maximum inflow of 3500m3/h from the point composed huge threaten tomine safety.