The Study Of The Interpretation Criterion For Low Permeability And Thin-poor Watered Out Zones In Longhupao Oilfield

Saertu oil reservoir in the western peripheral Daqing Placanticline belongs to fluvial, deltaic and inshore-shallow lake facies.The thickness of the sedimentary rocks is thin and the thin interbeds of sandstone and mudstone is rich. And furthermore, due to the control of multiple factors including faults, structures and lithology, these oil reservoirs have become complex low-medium permeability ones. The reservoir physical differences and the contradictions between interlayer are quite apparent. The forms of the sand distribution in different Blocks are also different.Longhupao oilfield is the early-developed and medium-low permeably oilfield in this area.The depth of the Saertu oil reservoir is between 1460m and 1530m. The lithologies are mainly the fine sandstone and Siltstone with mud. The clastic components of the sandstone are quartz,feldspar and debris and certain carbonate. The effective porosity in the Saertu oil reservoir is mainly between 14%and 23%, average in 18.7%.The air permeability is mainly between 0.4mD and 150mD, average in 40mD.Recently the research area has entered into the high water cut stage. Because of many factors, the water flooded degree of the Saertu oil reservoir is high and the water flooded zone is hard to identify in Saertu oil reservoir.Firstly, the response features and identifications of the well logging is bad which is affected by high mud and calcium in the waterflood front of the Saertu oil reservoir in Longhupao oilfield, the rich thin Interbeds and the thickness;secondly,affected by the depth of well logging's probe,the technology of the well logging can only be used to analysis the water flooded situation near the shaft and its plane distribution is hard to understand. And furthermore,due to the increased production in recently years, the seepage ane its law in the underground changes clearly and complex. Therefore it is necessary to start the the study of the interpretation criterion for watered out zones in long26 area of the Longhupao oilfield.Facing the difficulties about the interpretation for watered out zones in this area, on the basis of this reservoir classification,this project starts from water flooded the mechanism and analysis the changes of the resistivity and the different types of variation of reservoir petrophysical parameters during water flooded process. Setting up interpretation chart and standard of the water flooded zone respectively. Taking into account the limitations of the well logging,we can carry out logging pyrolysis and gas chromatography laboratory analysis by using the sidewall core data and establish methods of waterflood front by appling the material balance equation.Calculating the waterflood front by using the dynamic and static data of the encryption Well. Figuring out the plane situation of water flooded,we add and amend the interpretation results of the water flooded zone and establish a dynamic interpretation and process about well logging to mud logging.Through the study of this project,we explore some new methods about the water flooded zone of the low permeability oilfield in the western peripheral Daqing and can also provide certain experience basis to the other oilfield's Encryption...