Terrigenous Sequence Stratigraphy Characteristic Hydrocarbon Exploration Of Fault-depressed Lacustrine Basin: A Case Study Of Early Cretaceous, Honghaoersute Sag, Erlian Basin

From macro to micro and from qualitative to quantitative evaluation, this paper, applicating the theory and technological method of sequence stratigraphy, seismic stratigraphy-, reservoir sedimentology, combining with multispecialty and mutisubject theory that used geology, log, seismic, mathematics and earth physics and basing on synthetic application of regional geology, core, log, seismic and petrophysical property data, has studied the inner structure and characteristic of sequence, system tract and depositional system.Combining with high resolution seismic data and log data, this paper makes a profound analysis of the space pattern and reservoir predictability of depositional system on oil and gas pools of honghaoersute sag. By means of Kiba formation, K.ibt' and Kibt2 segments analysis on the equivalent time stratigraphic framework, subtle traps will be predicted on stratigraphic traps and lithological traps.The results from the research indicated that:(1) This paper further indicates the control significance of southern boundary fault displacement component, which downthrown side forms syncline or anticline, and points out that 4 anticlines in south are adjustment zone and are the entering lake position of ancient river. The structural framework gives rise to that the seg is intensivly indiscriminate and is major abeam migration.(2) This paper has firstly identified these genetic units on shore beach-shore face, longshore zone, longshore sands, erosional channel, leveed channel, turbidite lobes, turbidite sheet, slump, debris flow, density-modified grain flow etc; At the same time, and points out that the lake of Cretaceous is open-type fresh water lake.(3) 6 the 3rd-order sequence have been identified in early Cretaceous, the position of sequence is erected on 2 sets andesite.(4) A veries of depositional system of early Cretaceous have been identified firstly:basin floor fan, slope fan, leveed channel, subparallel facies, slump facies, lowstand wedge, TST, HST. Combining with seismic reflection and log response, this paper discusses distribution of above facies, microfacies and reservoir characteristics.(5) Based on the integrated sequence stratigraphy analysis of typical wells section and many well-to-well section, the control of hinge fault is confirmed.System tracts of downfaulted block perfectly develop, from lower position to higher position,upfaulted block (west-north region of the gentle slop) is in turn PGC, TST, HST,overlapping in SB. IVF provides important reservoir on gentle slope.(6) Deposition-Seismic response is obvious, 17 series (3 types) seismic facies have firstly been identificated in early Cretaceous and from seismic facies to deposition facies has been finished. There has been a certain recognition to sediment source, migration direction, depositional system distribution and reservoir favorable zones within sequence.(7) Reservoir heterogeneity is strong in intra-system tracts and in inter-system tracts. Four quantitative models of reservoir heterogeneity in intra-system tracts are reserched.(8) Hydrocarbon characteristic and system tracts have been analysised, and reservoir evaluation has been finished about middle-east sag. This paper points out 3( I type) hydrocarbon prospect and 4( II type) hydrocarbon prospect and favorable depositional condition of uncertain prospect is analysised too.