Sedimentary System Research On Putaohua Oil Layer Of Talaha-Yingtai Area

The first member of Yaojia Formation,Putaohua Reservoir of the lower cretaceous,is the study layer of Talaha-Yingtai area in Gulong Region,locating in western part of Qijia-Gulong sag of the central depressed area of Songliao basin.Previous have researched on the different blocks of this area,and put forward a number of different opinions.Based on previous studies,guided by the theories of sequence stratigraphy,sedimentology,re-division of the Putaohua Reservoir,and then carried out corresponding deposition system,to deepen oil sands development and reservoir characteristics,which provides the basis instruction for increasing on production.First,based on high-resolution sequence stratigraphy principles,focusing on selected study area in detail coring and high resolution core observation cycle interface identification,combined with logging,seismic data,establish Putaohua five-layer method and sequence comparison standards,build targan-Yingtai area Putaohua unified sequence stratigraphic framework,will Putaohua into a mid-cycle(PI reservoir group),three short-term cycles(PI upper,PI middle,PI lower).On the basis of division at all levels of the base-level cycle times,when short-term cycles,such as stratigraphic correlation of units in the study area were sequence stratigraphic correlation established Putaohua sequence stratigraphic framework.Within this sequence stratigraphic framework for the area to take the lithology and structure,core and logging data,single well facies,particle size analysis,well logs and other information for each port single well microfacies identification.Based on the coring detailed microfacies study,on the other did not coring wells logging data interpretation,looking strong point logging with flags attribute clustering analysis combined with seismic data,etc.treatment of sedimentary microfacies distribution sectional study in a peaceful face.Summarize the main sand body types in the study area,and the distribution of oil sexual relations.Combined with core and logging data,single well facies,we did a comprehensive study on single well facies,and then confirmed types of sedimentary faces in the study area which develops delta facies and lake facies in Putaohua oil layer.Delta front subfacies is the main subfacies,of which microfacies types mainly are underwater distributary channel,mouth bar,sand sheet,sub-sea crevasse channel and underwater distributary interchannels.Lake facies mainly develops shore-shallow lake microfacies.Heavy minerals data and sandstone content revealed that controlled mainly by the western provenance system and accidentally by the northern provenance system,source rock of this study area is mainly acidic magmatic rocks.On the basis of the study above,profile contrast were implemented and eight phase-plane diagrams in super-short-term cycle units were drawed,which established the time and space evolution of sedimentary system of this area.What we have achieved makes us believe that Putaohua reservoir deposits in a deepening water,sand body fading retrograding sedimentary sequence.