现代地质
現代地質
현대지질
GEOSCIENCE-JOURNAL OF GRADUATE SCHOOL CHINA UNIVERSITY OF GEOSCIENCES
2014年
5期
1017-1022
,共6页
张新超%孙赞东%赵俊省%潘杨勇%吴美珍
張新超%孫讚東%趙俊省%潘楊勇%吳美珍
장신초%손찬동%조준성%반양용%오미진
塔中北斜坡%走滑断裂%断距%拉分区域%油气分布
塔中北斜坡%走滑斷裂%斷距%拉分區域%油氣分佈
탑중북사파%주활단렬%단거%랍분구역%유기분포
the Northern Slope of Tazhong area%strike-slip fault%displacement%pull-apart area%petroleum distribution
塔中北斜坡奥陶系碳酸盐岩的储层改造和油气分布,都受到走滑断裂的影响。由于区域内较大规模的走滑断裂均表现为北东向,水平断距较小,使得利用地震资料直接计算断距时存在着较大的困难。实际上,走滑断裂还普遍表现出北西向拉张特征,并沿断裂走向形成了宽度不同的拉分区域。断裂多沿北东向平直延伸,表明这些拉分区域的宽度和高度主要是受局部应力作用而形成的。这些拉分区域的宽度和高度在三维地震资料中较容易识别。根据断裂的拉分特征,提出通过计算拉分区域的宽度和高度间接识别走滑断裂的断距的方法。断距计算结果符合走滑断裂发育的地质规律,断距较大处是走滑断裂活动性较强的区域,同时也是储层改造作用强烈和油气分布较好的区域。
塔中北斜坡奧陶繫碳痠鹽巖的儲層改造和油氣分佈,都受到走滑斷裂的影響。由于區域內較大規模的走滑斷裂均錶現為北東嚮,水平斷距較小,使得利用地震資料直接計算斷距時存在著較大的睏難。實際上,走滑斷裂還普遍錶現齣北西嚮拉張特徵,併沿斷裂走嚮形成瞭寬度不同的拉分區域。斷裂多沿北東嚮平直延伸,錶明這些拉分區域的寬度和高度主要是受跼部應力作用而形成的。這些拉分區域的寬度和高度在三維地震資料中較容易識彆。根據斷裂的拉分特徵,提齣通過計算拉分區域的寬度和高度間接識彆走滑斷裂的斷距的方法。斷距計算結果符閤走滑斷裂髮育的地質規律,斷距較大處是走滑斷裂活動性較彊的區域,同時也是儲層改造作用彊烈和油氣分佈較好的區域。
탑중북사파오도계탄산염암적저층개조화유기분포,도수도주활단렬적영향。유우구역내교대규모적주활단렬균표현위북동향,수평단거교소,사득이용지진자료직접계산단거시존재착교대적곤난。실제상,주활단렬환보편표현출북서향랍장특정,병연단렬주향형성료관도불동적랍분구역。단렬다연북동향평직연신,표명저사랍분구역적관도화고도주요시수국부응력작용이형성적。저사랍분구역적관도화고도재삼유지진자료중교용역식별。근거단렬적랍분특정,제출통과계산랍분구역적관도화고도간접식별주활단렬적단거적방법。단거계산결과부합주활단렬발육적지질규률,단거교대처시주활단렬활동성교강적구역,동시야시저층개조작용강렬화유기분포교호적구역。
Reservoir reformation and petroleum distributions in Ordovician carbonate reservoirs are affected by strike-slip faults with northeast direction in the Northern Slope of Tazhong area.Large scale strike-slip faults al-ways show north-east strike direction.Unfortunately,the horizontal displacement is too shorter to be identified by using poor quality and low resolution seismic data.Strike-slip faults show ubiquitous pull-apart areas along the strike direction,because they have been affected by the tensional stress with northwest direction.And pull-apart areas are developed along the direction of strike-slip faults mainly affected by the formation of local stres-ses.The width and height of these areas are easy to be identified in 3D seismic data.A method is then proposed for displacement calculation by using the width and height of the pull-apart area to replace the horizontal dis-placement and vertical displacement of fault.Displacement calculation results by this method show a high agreement to geology regularity of strike-slip faults development.Large displacement in strike-slip faults al-ways means a high activity regional area,and also shows a profitability area for reservoir reformation or petro-leum accumulation.