西北地质
西北地質
서북지질
Northwestern Geology
2015年
4期
234-242
,共9页
微构造%鼻隆构造%低渗透油层%油气成藏%有利探区%勘探
微構造%鼻隆構造%低滲透油層%油氣成藏%有利探區%勘探
미구조%비륭구조%저삼투유층%유기성장%유리탐구%감탐
small structure%paleo-nose structure%reservoir formation%favorable exploration ar-ea%oil/gas exploration
低渗透岩性油藏成藏作用主要受控沉积相和成岩作用。但是，勘探实践表明，在砂体背景之上分布的微构造对低渗透油气成藏具有明显的控制作用。位于鄂尔多斯盆地中东部的丰富川油田西区为多层系低渗透复合含油区，油气成藏类型复杂多样。笔者以该区为例，在对该区主要含油层系微构造及其演化特征研究基础上，探讨鼻状隆起构造对油气富集成藏的控制作用。研究表明，丰富川油田西区在东高、西低的西倾单斜背景上发育多个自东向西倾没的鼻状隆起构造；本区侏罗纪古河道下切深度小，残余的长1厚层泥岩限制了油气向上运移，延安组石油富集程度明显弱于延长组。低幅度鼻状隆起微构造对长2和长4+5油气成藏具有明显的控制作用，长2油层组顶面构造高点清楚，微隆起构造对油气富集控制作用非常明显，长2油藏具上油下水特征，发育低水和边水，油水界面清楚，具有岩性构造油藏的基本特征。而长4+5和长6油藏除了岩性油藏外，也发育构造岩性复合油藏。研究表明，微构造研究对低渗透油层油气富集规律研究和老油区扩边勘探具有重要指导意义。
低滲透巖性油藏成藏作用主要受控沉積相和成巖作用。但是，勘探實踐錶明，在砂體揹景之上分佈的微構造對低滲透油氣成藏具有明顯的控製作用。位于鄂爾多斯盆地中東部的豐富川油田西區為多層繫低滲透複閤含油區，油氣成藏類型複雜多樣。筆者以該區為例，在對該區主要含油層繫微構造及其縯化特徵研究基礎上，探討鼻狀隆起構造對油氣富集成藏的控製作用。研究錶明，豐富川油田西區在東高、西低的西傾單斜揹景上髮育多箇自東嚮西傾沒的鼻狀隆起構造；本區侏囉紀古河道下切深度小，殘餘的長1厚層泥巖限製瞭油氣嚮上運移，延安組石油富集程度明顯弱于延長組。低幅度鼻狀隆起微構造對長2和長4+5油氣成藏具有明顯的控製作用，長2油層組頂麵構造高點清楚，微隆起構造對油氣富集控製作用非常明顯，長2油藏具上油下水特徵，髮育低水和邊水，油水界麵清楚，具有巖性構造油藏的基本特徵。而長4+5和長6油藏除瞭巖性油藏外，也髮育構造巖性複閤油藏。研究錶明，微構造研究對低滲透油層油氣富集規律研究和老油區擴邊勘探具有重要指導意義。
저삼투암성유장성장작용주요수공침적상화성암작용。단시，감탐실천표명，재사체배경지상분포적미구조대저삼투유기성장구유명현적공제작용。위우악이다사분지중동부적봉부천유전서구위다층계저삼투복합함유구，유기성장류형복잡다양。필자이해구위례，재대해구주요함유층계미구조급기연화특정연구기출상，탐토비상륭기구조대유기부집성장적공제작용。연구표명，봉부천유전서구재동고、서저적서경단사배경상발육다개자동향서경몰적비상륭기구조；본구주라기고하도하절심도소，잔여적장1후층니암한제료유기향상운이，연안조석유부집정도명현약우연장조。저폭도비상륭기미구조대장2화장4+5유기성장구유명현적공제작용，장2유층조정면구조고점청초，미륭기구조대유기부집공제작용비상명현，장2유장구상유하수특정，발육저수화변수，유수계면청초，구유암성구조유장적기본특정。이장4+5화장6유장제료암성유장외，야발육구조암성복합유장。연구표명，미구조연구대저삼투유층유기부집규률연구화로유구확변감탐구유중요지도의의。
Western exploration area of Fengfuchuan Oilfield,located in the middle-eastern part of Ordos Basin,is the multi-layer composite petroliferous region of low permeability,with compli-cated type of reservoir accumulation. And the development of micro structure controls reservoir enrichment of some layers. This becomes an important direction for expansion and continuous ex-ploration in oil region. This paper is based on the analysis of micro structural characteristic,for-mation and evolution in the Yan 9 ,Yan 8 of Yan′ an Formation and Chang 2,Chang 4 + 5, Chang 6 of Yanchang Formation which are the main oil-bearing sequences,and is based on the study of accumulation time and migration law,combined with the differences of multiple factors superposition of reservoir enrichment. And this paper shows the relationship between micro structure and reservoir enrichment. The micro structure is the nose-shaped uplift developed on the background of slope in different horizons,in which the nose uplift area developed in Yan 9, Yan 8,Chang 2 and parts of Chang 4 +5 reservoir and the main sandbody superimposition part become a favorable area for migration and accumulation of oil and gas. Synthetic analysis uses the relationship between micro structure in this region and reservoir enrichment,and selects 5 favora-ble exploration target areas in the study area. Of the 5 favorable exploration target areas,in Ding 20 well area,Yao 304 well area,Ding 85 well area and Yao 243 well area,the tectonic uplift of both sides of the zonal range is the key zone of oil and gas exploration in the Yanchang Forma-tion. The ancient branch valley and slope on both sides developed in the Renjiagou and Guozhuang become a favorable exploration area for ancient landform reservoir of Yanan Forma-tion. This study can provide a reliable guarantee for oil exploration in the future.
