| With the progress of developing technology,more and more proved low-permeability reserves have be discovered,and it has become an important field in energy development.Low permeability reservoir development relies mainly on the fracturing process,cracking the formation with fractures,whose permieability is much bigger than the formation,so that improving formation permeability,reducing the flow resistance of oil to wellbore,finally enhancing the oil recovery.However,most hydralic fractures in shallow and low-permeability reservoirs are horizontal fractures,which is definitily different from vertical fractures,thus research of horizontal fracture seepage mechanisim has an important significance to development of shallow and low-permeability reservoirs.This paper make Chang 6 formation of Yan Chang Oil Field as an example,and start the research with petrological characteristics,pore characteristics,and formation distribution characteristic,and in base on geological research,hydralic horizontal fracture cracking seepage characteristics was dicoverd.Then combining cracing seepage mechanisim with on-site fracuring data,getting 3 mehod of judging fracture morphology,which is applied well in Yan Yan Chang Oil Field.Based on Darcy Law Theory,making three-dimensional flowing experiment with one horizontal fracture model and double horizontal fractures model both are in large scale,which simulated flowing in horizontal fracures.Then dealing with experimental data,we found characteristics of pressure and streamline distribution,and revealed horizontal fracture seepage law.At last,in base on the Darcy Law Theory and flow experiment,and combining prodution in vertical and horizontal both direction,with consideration of pressure gradient,the productivity equation of vertical well with horizontal fracture was derivated.And then fractors effecting productivity were analisized,such as fracture length,fracture shape and pressure gradient. |
PDF Full Text Request