Sedimentary Characterization Of Outcrops Of Quantou Formation In Songliao Basin

The Cretaceous Quantou formation in Songliao Basin is one of the main exploration target layer,Quantou strata sporadically exposed in the eastern part of the Songliao Basin,the strata generally Exposed incompletely and thin,so it's necessary to study the deposition characteristics and the sequence characteristics of the Quantou formation in Songliao Basin.As the theoretical guide to sedimentology,sequence stratigraphy and other related disciplines,on the section's location and geological research,selected the best field outcrop of Quantou Formation stratigraphic profile for location survey,based on the profile of a lithological description,sample analysis,sedimentary type research and sequence stratigraphic division and contrast,Summarize the lithologic features,the sedimentary facies types and evolution,the characteristics of sequence stratigraphy and reservoir characteristics of Quantou Formation outcrops in Songliao Basin.Using a variety of field identifications of sequence interface,Two three-order sequence boundaries were identified in the Quantou Formation outcrops in Songliao Basin in total,the outcrops of Quantou Formation is divided into three three-order sequences.In each sequence unit established the sedimentary mode of the studied profile through phase symbol recognition,and carried out a detailed analysis On the internal structure of the sedimentary system,carved out a total of three kinds of sedimentary facies,seven kinds of sedimentary subfacies and 12 kinds of sedimentary microfacies types.The sedimentary facies of outcrops of Quantou Formation in Songliao Basin include alluvial fan facies,braided river facies and meandering river facies.According to the landform features and sedimentary characteristics,the alluvial fan facies can be further divided into two subfacies which are fan-in and fan edge.There grow debris flow sedimentary micro facies,sedimentary microfacies and flowing river sedimentary micro facies in the two metastable phases,In the su'bphases,it developed riverbed detention sedimentary microfacies,batture sedimentary microfacies and sedimentary microfacies of river floodplain.Between the second and the third section of braided river facies,it deposited a sequence of meandering river facies.In the meandering river facies,there developed river bed subfacies and fluvial overflow facies.In the subphrase,there developed rivered stranded microfacies,beach sedimentary microfacies edimentary microfacies,natural levee,crevasse splay sedimentary microfacies and sedimentary microfacies of river floodplain.