Abstract: The fracture characteristics of Feixianguan Formation in Xuanhan area were analyzed by whole diameter
core observation and thin section analysis information， and the growth state and longitudinal distribution of frac-
tures were studied from conventional logging data at every well； Based on ahead of analysis， fracture genesis was
researched deeply through combined with geological structures in east of Sichuan. The results show that vertical
tectonic， horizontal， diagonal and diagenesis fractures mainly develop at the lower of Feixianguan Formation； there
are two kinds of fracture that is tectonic and non-tectonic， and tectonic fracture is associated with faults， drape and
weak deformation areas， which has three kinds of mechanical causes， which are shear fractures， expansion fractures
and tensile fractures. Non-tectonic fractures can be divided into four kinds， which are diagenetic fracture， corrosion
fracture， shrinkage fracture， supergene fracture. The production practice indicates that any fracture in carbonate
reservoirs is important in both storage space and the flow channel.

Key words: carbonate rock, tectonic fracture, non-tectonic fracture, Feixianguan Formation, conventional logging