【摘要】：TX盆地位于我國某海域內(nèi),是我國海上油氣勘探程度較低的含油氣盆地之一。本論文研究區(qū)為TX盆地內(nèi)的西部凹陷,其勘探及研究程度較低,是否存在良好油氣資源條件是目前需要解決的問題。本論文的研究目的層為漸新統(tǒng)-中新統(tǒng),研究內(nèi)容為其內(nèi)部沉積體系的展布特征描述。前人已有的研究成果表明,該研究層段主要為海相沉積地層,內(nèi)部發(fā)育的優(yōu)質(zhì)砂巖儲層與下部深湖相烴源巖及上部區(qū)域性蓋層形成一套良好的生、儲、蓋油氣系統(tǒng)。因此,刻畫研究區(qū)內(nèi)中新統(tǒng)-漸新統(tǒng)層位內(nèi)部砂體分布特征,恢復(fù)相應(yīng)沉積體系,對TX盆地西部凹陷油氣地質(zhì)條件的研究具有較大意義。針對該問題,從前人對TX盆地西部凹陷地質(zhì)構(gòu)造背景、地層與沉積特征、盆地構(gòu)造特征等研究成果出發(fā),通過與鄰區(qū)相關(guān)地震特征、地層、層序?qū)Ρ?以地震資料為基礎(chǔ),應(yīng)用地震線描方法進行沉積盆地原始結(jié)構(gòu)重建,確定沉積環(huán)境。在此基礎(chǔ)上,選取研究區(qū)內(nèi)典型地震剖面來識別目的層內(nèi)部砂體,刻畫地震相并圈定優(yōu)質(zhì)砂體,確定其發(fā)育規(guī)律及展布特征。利用源控+相控的方法,建立三角洲-斜坡-深水扇的沉積體系脈絡(luò)關(guān)系,并結(jié)合相應(yīng)的沉積環(huán)境、水流體系等,實現(xiàn)研究區(qū)沉積體系綜合分析。最終基于沉積體系的研究,開展一定程度的油氣地質(zhì)條件研究分析。通過本次論文研究,取得了以下幾方面認(rèn)識:(1)根據(jù)地震資料分析,初步確定調(diào)查區(qū)新生界存在8個主要地震反射界面,其中T3、T6、T8-1、T9、Tg為五個區(qū)域性大型角度不整合面,并依此劃分、識別出研究區(qū)第三系發(fā)育Ⅰ-1,Ⅰ-2,Ⅱ-1,Ⅱ-2和Ⅱ-3五個構(gòu)造層序。(2)在對地震剖面精細(xì)解釋刻畫的基礎(chǔ)上,通過地震線描方法進行沉積盆地原始結(jié)構(gòu)的重建,確定研究區(qū)漸新統(tǒng)當(dāng)時的沉積環(huán)境為淺海陸架和半深海陸架內(nèi)洼陷環(huán)境、中新統(tǒng)為大陸邊緣陸架環(huán)境;又通過對地震反射特征的識別與歸類,在研究區(qū)共識別、劃分出6種優(yōu)勢地震相,并對每一種地震相進行了地質(zhì)意義分析,確定了研究區(qū)的優(yōu)勢沉積相分布,為沉積環(huán)境特征分析提供了重要依據(jù)。(3)通過波形分析,結(jié)合鄰區(qū)已驗證實例,確定研究區(qū)骨架砂體巖相的波形特征,在研究區(qū)目的層位進行砂體掃描,確定不同類型砂體的時空展布,再結(jié)合沉積相分布與沉積環(huán)境特征分析,確定研究區(qū)目的層位中新統(tǒng)、漸新統(tǒng)的沉積體系,劃分出三角洲、淺海陸架、斜坡等相帶,確定三角洲-深水扇的脈絡(luò)關(guān)系。
[Abstract]:The TX basin, which is located in a certain sea area of China, is one of the oil and gas bearing basins in China. The research area of this paper is the western sag in the TX basin, its exploration and research degree is low, whether there is good oil and gas resource condition is the problem that needs to be solved at present. The purpose of this paper is the Oligocene-Miocene, and the research content is to describe the distribution characteristics of the internal sedimentary system. The results of previous studies show that the studied formation is mainly marine sedimentary formation, and the high quality sandstone reservoir developed in the interior forms a good system of generation, reservoir and cap oil and gas with deep lacustrine source rocks and upper regional caprocks in the lower part. Therefore, it is of great significance to study the oil and gas geological conditions in the western sag of TX basin by characterizing the distribution characteristics of sand bodies inside the Miocene-Oligocene horizon and restoring the corresponding sedimentary systems in the study area. In order to solve this problem, the previous studies on the geological structure background, stratigraphic and sedimentary characteristics and basin structural characteristics of the western sag of the TX basin, based on seismic data, are based on the correlation of seismic characteristics, stratigraphy and sequence with adjacent areas. The original structure of sedimentary basin was reconstructed by seismic line drawing method, and the sedimentary environment was determined. On this basis, the typical seismic profiles in the study area are selected to identify the sand bodies in the target layer, to depict seismic facies and to delineate the high-quality sand bodies, and to determine the development and distribution characteristics of the sand bodies. By means of source-controlled facies control, the sedimentary system of delta-slope-deep-water fan is established, and the sedimentary system in the study area is analyzed synthetically by combining the corresponding sedimentary environment, flow system and so on. Finally, based on the study of sedimentary system, a certain degree of oil and gas geological conditions research and analysis. Based on the analysis of seismic data, it is preliminarily determined that there are 8 main seismic reflection interfaces in the Cenozoic region of the survey area, among which T3T6 T6-T8-1T9; Tg is a regional large angle unconformable surface, according to which, the Tertiary development 鈪，

本文編號：2379610