Font Size: a A A

Study On Sequence Stratigraphy And Reservoir Characteristics Under Sequence Stratigrapy Framework: In The Devonian, Southern Guizhong-Middle Guangxi Area

Posted on:2009-08-21Degree:MasterType:Thesis
Country:ChinaCandidate:J W KangFull Text:PDF
GTID:2120360242992977Subject:Sedimentology
Abstract/Summary:PDF Full Text Request
Under the guidance of new principles and methods of modern Carbonate Petrology, Sedimentology, Sequence Stratigraphy and Reservoir Sedimentology, this thesis has taken the strata of Devonian in Southern Guizhou and Middle Guangxi area as the main targets of the study and has carried out detailed research work on sedimentary systems, sequence stratigraphy, lithofacies-paleogeography, reservoir characteristics under Sequence Stratigrapy Framework.Based on the core, geology logging, areal geology from many field-profiles and wells, combined with the data of regional sediment and structure, according to the analysis of the characteristics of different rocks, sedimentary structure and profile framework, four types of sedimentary system including shelf system, platform system, platform-basin system and platform-slope system have been recognized , and various facies, subfacies and microfacies developed in each system have also been discussed. melange shelf facies mainly develop in the shelf system. platform-basin system is the mose characteristic. Because of the change of the water depth and sedimentary sources, many kinds of sedimentary combination and cross section have formed,. Based on the origin and lithofacies, the types of platform-basin included mud stone-turbidite,mud stone- silicalite,mud stone- marlstone,silicalite- limestone have been identified.Based on the study of sequcence boundaries, the types of the sequcence boundaries can be included weathering crust,Action surface of ancient karst,Washing erosionsurface of gravity flow on slop,Transition surface of rock character and facies,on-lop surface,mfs. Depending on the recognization and characteristics of sequcence boundaries, the Devonian stratum of Southern Guizhou and Middle Guangxi area can be divided into 2 second-order and 18 third-order sequences, No.1 second-order includes 10 third-order(from No.1 to No.10) and 3 Systems tract included LST, TST,HST. No.2 second-order includes 8 third-order(from No. 11 to No. 18) and 2 Systems tract included TST,HST. whose system tracts have been detailedly discussed. Sequence stratigraphic correlation through the study area has been implemented and the isochronous sequence stratigraphic frameworks have been established. The following four have been discussed as emphases: sea-level changing, tectonic settlement, sediment supply and climate and their models have been produced respectively..Have drawn the picture of lithofacies-paleogeography and sequence stratigraphy based on regional Sedimentology and the contrast of Sedimentology Sequence stratigraphic. From the date of large-scale marine transgression in the later of Lower Devonian,space is different of the another. Third-order sequence have different facies association in the different sedimentation setting. depositional environment changed from shallow water platform to deepwater platform-basin from south to north. platform interleaving platform-basin in Devonian System is unique feature.Reservoir Types have been generalized which mainly include: biogenic reef reservoir, carbonate reservoir, hole-cavity reservoir. biogenic reef reservoir distributing on the hanging side and develop superposition reef along the platform margin. carbonate reservoir in the isolated platform and slope is best reservoir. Different reservoir have different control facters. biogenic reef reservoir,and carbonate reservoir are mainly effected by the change of sea level, sedimentary facies, diagenesis. hole-cavity reservoir developments in karstified carbonate and on both sides of dislocation and in the core corrugation,which is controlled by tectonism. mean sea-level changes influence temporal and spatial distribution and rule of the reservoir in the Sequence stratigrphy framework. The gradation of the best reservoir in the different precipitation facies is generalized from platform margin reef,beach in the platform,platform margin beach,slop,platform,ocean trough. Compaction solution and cementation of calcite destroy reservoir, dolomitization and dissolution effect meliorate reservoirBased on sedimentary facies and sequence stratigraphy and sequence stratigraphy lithofacies-paleogeography, under the sequcence stratigraphic framwork, the different kinds of reservoirs origin have been generalized:1. reservoir controlled by interface of sequence stratigraphy 2. reservoir relating TST 3. reservoir relating HST .Result shows that the favorite reservoirs include reef and bank carbonate reservoir developed during TST and reef and bank carbonate reservoir, dolomite reservoir developed during HST, Based on study of those, favorable targets have be forecasted...
Keywords/Search Tags:Southern Guizhong and Middle Guangxi area, Devonian, Carbonate sequence stratigraphy, Lithofacies-paleogeography, Sequence stratigrphy framework, Reservoir Types, Regularities of distribution
PDF Full Text Request
Related items