Research On Upper Ordovician Reservoir Characteristics Of Reef Bank In Tazhong62 Well Area

Under the guide of the theories of advanced carbonate diagenesis and reservoir geology,and associating with the newest progress relevant domestic and abroad,systermatically researched the reservoir characteristics, property,pore texture,division and evaluation of upper Ordovician reef bank inTazhong62 well area both from macrography and micrography.Pointing to the feature that the strata developed controlled by palergeomorphy,reef bank grew upward and sea level relative variability,then on the basis of synthetically analyzing Hthology and logging curves features,and applying the theories of sequence stratigraphy,divided Lianglitage Formation into TST and HST from bottom to top,and 3-4 parasequence sets,8 parasequences,and 11 members.furthermore, recognized shelf margin reef,grain bank, shelf margin bioherm and interbank sea these four facies and 12 subfacies.Analyzing associating with reservoir diagenesis and main controlling factors,established the reservoir developed pattern and porosity evolution sketch map.pointed out the first time that the development of upper Ordovician reef bank reservoir were controlled by the reef's geomorgraphy,reef facies combination and fresh water dissolution,that is to say the distribution of reservoir and oil pool fitting the reef's geomorgraphy.this is meaningful to explore or predict this kind of slopes both in reality and theory.Researched the reservoir developed feature and changing regularity laterally,predicted the reservoir distributing regularity,established the reservoir geological pattern, synthetically evaluated and predicted good reservoir distribution and favorable exploring goal .point out that the reservoir interzone was fissure-pore type, outer zone were fissure-hole and cave types,what was significant to the next exploration.