Fracture Character And Distribution Evaluation Of Fracture In Xuer, Xinchang Area

In the laboratory part, observed the core from14wells, analysed the type, occurrence, lithology, density, length, width, filled condition of the fractures, and further, use the FMI to defined the open fractures, the half filled fractures and the full filled fractures. From the compare of identified fracture and the well log, analyse the well log characteristic of the fractures, build up a standard of identify the fractures. Contemporary, use several methods to identify the fractures,such as, distinguishing method、R/S method、probabilistic neural network. Then, compare the identification results with the fractures which were seen on the cores. Finally, On the basis of structural curvature、paleo-structural stress field simulation and structure filtering, this paper generalize the fracture development of the second member of Xujiahe formation in Xinchang area.Summarize the observation of outcrop, core and well log exploration, the fracture in the study field represent to many groups, mainly strike direction are NEE-SWW, W-E, NE-SW, the development of nature fracture effected by the structure, lithology, depth of the formation, fault and crustal stress。Most of the fractures are low-angle fracture followed by high-angle fracture and vertical fracture, the majority of the fractures are half filled fracture, filled by calcite, part of them are filled by mud and carbon. Finally, use comprehensive evaluation Fa to evaluate the distribution of fracture on the plane, the fracture of the study area can be divided into two types:development areaand not development area.