松遼盆地南部中淺層沉積演化與油氣分布

1、松遼盆地南部中淺層沉積演化與油氣分布        松遼盆地南部蘊藏著豐富的油氣資源,目前探明儲量主要集中在泉三段至嫩江組中淺層儲層。本論文是以儲層沉積學、石油地質學和油氣成藏動力學為理論指導,綜合利用地質、地球化學、地球物理和分析化驗等資料,開展沉積體系研究及有利儲集體相帶劃分,確定松遼盆地南部中淺層沉積相類型與分布規(guī)律,建立沉積演化模式,對不同沉積類型的各相帶進行綜合評價。結合該區(qū)油氣成藏主控因素和成藏模式,對有利區(qū)域進行預測,從而達到開拓油氣勘探新領域的目的。根據詳細的巖心觀察和描述,結合測井資料、區(qū)域地質資

2、料及各項分析化驗資料等進行綜合分析,確定了松遼盆地南部中淺層的沉積體系分布規(guī)律,識別出了辮狀河、曲流河、末端扇、辮狀河扇、三角洲、淺水三角洲、辮狀三角洲與灘壩等沉積相類型,同時提出了新的沉積模式與沉積演化規(guī)律。泉三段沉積時期,氣候環(huán)境炎熱干燥,主要發(fā)育河流-末端扇沉積體系,河流相包括曲流河與辮狀河。泉四段沉積時期,研究區(qū)內沒有統(tǒng)一的匯水中心,同樣以河流-末端扇沉積為主,研究區(qū)西北部發(fā)育辮狀河扇-曲流河沉積。青山口組主要發(fā)育三角洲沉積和淺水三角洲沉積,砂體主要分布在西部地區(qū),物源主要來自西部、西南部和南部,研究區(qū)東部為泥質沉積。姚家組沉積時期,西北部英臺-白城水系發(fā)育辮狀三角洲,西南部通榆-?？?/p>

3、水系、南部長春水系發(fā)育淺水三角洲沉積。嫩一段和嫩二段主要發(fā)育濱淺湖和半深深湖沉積,零星分布薄層砂灘砂體。從嫩三段開始到嫩五段,水體逐漸變淺,湖盆范圍縮小,北部物源主要發(fā)育三角洲沉積,南部缺乏恒定物源注入?；趯嶒炇曳治鲑Y料,研究了松遼盆地南部中淺層儲集空間類型,分析了不同沉積相類型各相帶和儲集巖儲集性質的關系,對不同沉積相帶的儲集體進行了綜合評價,確定了有利相帶分布范圍。研究認為,三角洲前緣水下分流河道與河口砂壩、末端扇分流河道、辮狀河扇中部亞相辮狀河道、河流相河道亞相儲層物性較好。河流相堤岸亞相、淺水三角洲分流河道、三角洲前緣遠河道與遠砂壩、前緣席狀砂、末端扇河道漫溢相儲層物性次之。河流相河

4、漫灘、末端扇泥灘沉積與遠端盆地、前三角洲及分流間地區(qū)儲層物性較差。采用油氣成藏組合觀點,在平面、剖面上研究油藏的分布特點,分析了油氣的分布與烴源巖分布、有利儲集相帶分布、油氣輸導體系等之間的關系,確定了油氣分布的主要控制因素,總結了油氣分布的規(guī)律性認識。松遼盆地南部中淺層油氣分布主要受烴源巖分布、儲集體分布、有利的生儲蓋組合配置、有效的圈閉與斷層等因素的影響。在區(qū)帶成藏條件和油氣分布控制因素研究的基礎上,分析了松遼盆地南部中淺層不同區(qū)帶的成藏機理,對有利目標區(qū)域進行了預測There are abundant hydrocarbon resources in the south of Songl

5、iao Basin. The proven reserves mainly concentrate in the middle-shallow layer of the third member of Quantou formation to Nenjiang formation at present. This thesis is on the instruction of reservoir sedimentology, petroleum geology and hydrocarbon accumulation dynamics. Setting up the rearch of sed

6、imentary system and classify of profitable facies belt in middle-shallow layer in the south of Songliao Basin using geology, geochemistry, geophysics and analyzed assay datum. To establish the sedimentary facies type and its distribution pattern, and sedimentary evolution mode. Evaluate each facies

7、belts of different sedimentary facies comprehensively. Predict the range of profitability combine with the master factors of hydrocarbon accumulation and accumulation mode of Middle-shallow layer in the south of Songliao Basin. So obtain the object to uncover the new region of exploration activity.A

8、ccording to the detailed observation and description of core, progress the synthesized analysis by combinbing the well logging, data of areal geology and all kinds of analyzed assay datum, assured the distribution regular pattern of sedimentary system in this area. Braided river, meandering river, t

9、erminal fan, braided river fan, delta, shallow delta, braided delta and beach bar sedimentation types are identified, and bring forward the new sedimentary mode and Sedimentary evolution regular. The climate is heat and arid in the third member of Quantou formation, and river-terminal fan sedimentar

10、y system develops in this period. There is no unitary water catchment center in the fourth member of Quantou formation, river-terminal fan sediment is the major sedimentation type, braided river fan-meandering river develops in the northwest of research area. Delta and shallow delta develops in the

11、Qingshankou formation. The sand body distributes in the western area, the provenance come from the west, southwest and south of the research area, the east is muddy sediment. The braided delta develops in the northwestern Yingtai-Baicheng water system in Yaojia formation,and shallow delta develops i

12、n the southwestern Tongyu-Baokang water system and southern Changchun water system. The shore-shallow lake and hemi-deep-deep lake develop in the first and second member of Nenjiang formation, and thin bed beach sands distribute fragmentarily. The water body becomes shallow and the lake basin reduce

13、s from the third member of Nenjiang formation to the fifth member of Nenjiang formation, delta develops from the north provenance, and the constant provenance absent from the south provenance.The reservoir types in the middle-shallow layer in the south of Songliao Basin are studied based on the anal

14、ytical data from the laboratory, and the relation between facies belts and reservoir characters of different sedimentary facies are analyzed. The reservoir of different facies belt are evaluated, and profitable facies belts are defined. The result shows that the reservoir quality of underwater distr

15、ibutary channel and channel mouth bar of delta front, distributary channel of terminal fan, braided channel of middle braided river fan and the channel of river facies are well. The reservoir quality of bank of river facies, distributary channel of shallow delta, distal bar and distal channel of del

16、ta front, sand sheet, overbank of terminal fan take second place. The reservoir quality of flood plain of river facies, mud flat and distal basin of terminal fan, predelta and interchannel area are bad.Take the point of hydrocarbon accumulation association to study the planar and sectional distribut

17、ion pattern of petroleum reservoir. The relation between petroleum distribution and sources rocks distribution, profitable facies belt, petroleum dredge system and so on. Summary the regularity recognition of petroleum distribution. The petroleum distribution in the middle-shallow layer in the south of Songliao Basin is under the control of sources rocks distribution, accumulate facies belt, profitable association of source rock, reservoir and cap, effective trapping and fault and so on. The hydrocarbon accumul