目前海域油气勘探,对地球物理资料依赖性高,但海上地震、地质资料有限,导致研究区精细地质认识不清.东海西湖凹陷H气田目前已认识到断裂是本区成藏关键,本次研究以新采集的海上宽频宽方位地震资料为基础,提高成像精度,运用各种地震解释方法,开展精细构造解释和特征分析,明确断裂特征、演化和成藏规律,并进一步明确气田南部有利区域,指导勘探方向,为类似构造区域研究提供新研究思路.

西湖凹陷是东海陆架盆地中重要的含油气凹陷,近期勘探证实渐新统花港组是当前主力产气层段;截至目前,西湖凹陷花港组层序地层划分方案还存在较大争议,严重制约了砂体等时对比及油气精细勘探进程.依据层序地层学结合天文旋回理论,利用小波变换和INPEFA技术对自然伽马曲线进行数学分析得到小波信号曲线、频谱及INPEFA曲线,建立了西湖凹陷花港组年代标尺及高精度层序界面格架.通过小波变换将GR曲线重构成不同阶次的小波信号曲线和频谱,以异常振动和能量团变化趋势凸显层序界面和旋回信息;同时,利用最大熵谱分析技术对GR曲线进行积分处理获得INPEFA曲线,以拐点和正负趋势定量拾取层序界面和旋回特征,将花港组划分为5套三级层序(自下而上分别命名为SQ1—SQ5).利用频谱分析明确三级层序内部地层叠置旋回,结合小波信号曲线变化特征,可将花港组划分为12套四级层序(自下而上分别命名为H12—H1).花港组GR曲线的多窗口频谱分析结果表明,5套三级层序发育持续时间介于1～3 Myr.通过多尺度多方法融合测井技术对缺少岩心和古生物化石区构建多级次等时层序地层格架具有一定推广意义,为渐新统花港组后期勘探开发提供一定的技术支持.

Forced regression is common during geological history, but due to mismatched sources andsupplies, there are fewer geological records and fewer research cases. Taking the 4th member of Weizhouformation in the Early Oligocene of Weixi'nan Sag in the Beibu Gulf Basin in the northwest of the South China Sea as the research object, the restoration of paleo-water-depth is carried out by using the seismic reflectionstructure method, the variation characteristics of paleowater depth under the background of forcedregression are clarified, and the restoration method of paleowater depth by using the delta progradationstructure method is further discussed. The research shows that during the deposition of 4th member of Weizhou Formation in the Early Oligocene, the provenance of Weixi'nan Sag was sufficient, a large incisedvalley was developed around it, and a large oblique progradation reflection structure was developed in thesag, which has typical Forced Regression characteristics, forming a large-scale forced regression systemtract. Through the fine dissection of typical progradation sections, six typical progradation reflection layersare identified. Combined with seismic, drilling and compaction coefficient, the paleo-water-depth of thelake basin is restored to be 111.2-286.5 m, with an average of 218.5 m. From the edge of the paleo-laketo the center, the height and dip angle of the progradation layers increase slowly and then decrease rapidly.In terms of water depth, it is about 230 m in the early stage, gradually deepened to about 280 m in themiddle and late stage, and rapidly decreased to 110 m in the last stage, with a change range of 61.5% comparedwith the maximum water depth; The dip angle of progradation layer is about 10° in the early stage, gradually decreases after reaching 14.5° in the middle stage, and changes rapidly to 2.9° in the final stage, with a change range of 79.8%. Combined with the regional geological research, it is considered that thegeological period experienced during the deposition of 4th member of Weizhou Formation is less than 2 Ma, and the paleowater depth and paleodip angle of progradation layers change rapidly and violently in lessthan 2 Ma, which is basically consistent with the characteristics of forced regression, which confirms theresponse characteristics of seismic reflection structure. Further, the feasibility and future research directionof paleo-water-depth restoration using delta progradation structure are discussed from the perspectiveof theoretical model simplification and restoration parameter optimization. The research results provide animportant reference for enriching the understanding of the variation characteristics of paleowater depth underthe background of forced regression.

受限于有限的断层表征手段,目前针对复杂断块油气田的断层封堵性尚无有效的综合评价方法.基于体元的构造建模技术,能够不受地震解释质量的限制,精确地在三维空间里建立地质模型.进一步依据三维地质模型,从几何形态、粗糙程度、断层与地层接触关系、断层两侧岩性对接情况以及断层泥岩涂抹等5个方面对断层面进行断层封堵性特征描述,再用神经网络算法对断层封堵性各项指标进行综合分类评价.通过实例样本的应用,为开发阶段高精度断层封堵性研究提供了思路,证实使用基于体元的构造建模技术为基础的复杂断层封堵性研究相对于传统方法具有明显优势.

东海深层HG组目的层埋藏深(＞3500m),储层具有低孔低渗特征,但局部发育“甜点”储层.由于“甜点”储层界限模糊,且与差储层及致密层地球物理响应差异小,因而预测难度大.为此,首先从井出发,在“甜点”储层主控因素分析的基础上,结合动态分析测试成果,建立分类储层综合评价标准,定义“甜点”储层界限;然后开展分类储层岩石物理分析,研究储层岩相及“甜点”储层弹性参数敏感性,通过叠前同时反演确定储层岩相及优质储层展布;最后,采用叠前AVO敏感属性流体检测技术预测含气富集区带,有效刻画“甜点”储层展布.实际应用结果表明,这种方法极大提高了研究区“甜点”储层预测的精度,为落实分级储量规模、部署开发井位和优化调整方案提供了科学的地质依据,在相似气田开发中有一定的借鉴意义.

平湖油气田经过近二十年的开采,目前已经步入开发后期.P1气藏作为平湖油气田曾经的主力产气层,由于生产井相继出水,且出水迅猛,导致三口生产井相继水淹关井.开发生产动态综合分析认为,P1气藏虽然开发井水淹,但气藏仍存在一部分剩余气.若将这部分潜力找到并有效动用,对于缓解平湖油气田生产形势有非常积极的作用.文章主要从地震、地质和油藏动态等多方面资料对P1气藏的出水来源和方向进行分析,认为P1气藏出水主要来源于放二断层开启,引入花港组地层水,大量出水使气藏中形成“水道”,致使北部B6井区还存在一定剩余气分布.

针对西湖凹陷B气田开发过程中发现的一套含气凝灰质砂岩进行研究.根据现有资料,重点利用钻录井、测井、地震、分析化验及测试数据,运用地震地质综合研究的方法,采用点—线—面—体的研究思路,对B气田凝灰质砂岩成因进行研究,分析其成藏模式,评价其勘探开发潜力,为B气田后续开发及挖潜提供依据.

深水海底扇储层蕴藏着丰富的油气资源,随着勘探开发技术的不断提高,海洋深水区成为油气勘探开发的热点.此文以A油田C油藏海底扇储层为例开展沉积相研究,利用地震、测井资料多学科精细表征储层静态特征,结合生产动态资料进行动静态互动分析.应用地震切片技术研究沉积相,解决了开发生产过程中的矛盾,评价了储层非均质性对油藏开发的影响,有助于深水海底扇储层的高效开发,同时也为开发方案的优化调整提供了可靠的地质依据.

东海西湖凹陷平北K气田平湖组为半封闭海湾相沉积,储层埋藏深,压实作用明显,且砂泥岩纵波阻抗叠置.引入横波资料后,通过测井平面均一化和岩石物理分析,认为Vp/Vs可识别储层.运用叠前同时反演,对K气田平湖组储层进行了预测,同时叠合储量计算线,为K气田开发井钻前优化提供建议.

大多数油田经过多年的高速开发使地下资源的丰度逐年变差,剩余油分布十分零散,油藏描述困难大,找到这部分剩余油难度大,将其开发出来,难度更大;过去一些行之有效的短平快增产措施,进入特高含水阶段后,这样的措施几乎已经挖掘殆尽;主力油田普遍进入特高含水、原油产量递减阶段,稠油热采进入高轮次吞吐阶段,吞吐效果变差,高效措施减少,投入产出效果变差,高效产量所占比重有所降低。针对目前的开发形势,采用精细油藏描述和精细地层对比技术,搞清剩余油的空间分布,提高原油采收率,挖潜老区剩余油。