地质-地震储层预测技术及其在渤海海域的应用

利用地震进行储层预测是石油勘探的必要和必须技术,对高风险、高投入、钻井少的海上油气勘探来说具有更为重要的意义。地质-地震储层预测技术的核心是地震和地质的紧密结合。与勘探进程上由构造油气藏向隐蔽油气藏勘探转变相适应,地震-地质结合也必须由宏观、描述、类比层次向精细、成因、动态层次延伸,注重由分析不同沉积相带砂泥岩波阻抗关系出发,通过建立正演模型来确定不同地震属性的地质意义;注重将不同体系域地震反射特征的变化与A/S比值、现代三角洲类型联系起来,从而通过地震剖面及其平面特征刻画不同体系域砂体特征,为寻找不同类型隐蔽圈闭指明方向。储层预测从层序地层学应用到地震沉积学充分体现了地震与地质结合的两个层次。地质-地震储层预测技术为渤海海域近年来探明的储量快速增长做出了巨大的贡献,同时也促进了沉积储层研究的发展。

火山岩地层地震反射特征和地震-地质联合解释:以徐家围子断陷为例

火山岩地层的地震反射特征可通过地震参数、反射结构与地震相、地震地层结构进行地质解释.徐家围子断陷营城组是一套以火山岩占优势的火山岩地层.钻遇营城组钻井与地震资料匹配给出了各种地震属性、反射结构和地震相的地质解释.在徐家围子断陷地震三维工区开展的火山岩地层的地震一地质联合解释包含三个层次:地震参数、反射结构与地震相、地震地层结构,反映火山作用和与相关的沉积作用的地层记录,其中反射结构与地震相是解释的重要环节.平行和发散反射结构可出现在自火山斜坡至盆地的环境,是火山物质较连续的展布和平稳堆积.前积反射结构可出现在火山斜坡至盆地的过渡环境,是火山物质的不连续和快速堆积.丘状和披盖反射结构可出现在火山口至盆地的各种环境中,与岩浆穹窿和基浪沉积有关.充填反射结构可出现在许多环境中,是火山物质下切冲蚀作用形成的.火山岩地层地震-地质解释遵循由大到小和由粗而细的原则,对应地震参数、反射结构与地震相和地震地层结构.

地震-地质综合研究方法述评

在油气勘探技术的发展过程中,地震技术和地质思维方式不断结合,相继产生了地震地层学、层序地层学和地震沉积学。地震地层学探索地震反射相位与地质层位、沉积相之间的关系;层序地层学分析地震反射特征与地质构造、岩石沉积的成因联系;地震沉积学是一门新兴的综合研究方法,尝试寻找地震特殊处理与解释、地震特征属性与地层沉积特征的内在联系。油气勘探技术的发展趋势将主要使用地震第三级特征属性,尝试进行地震储层、流体地震识别的研究。文中从基本概念、基本原理、研究方法和地震-地质综合解释4方面进行了综合阐述,并对其主要在陆相湖盆的应用进行对比分析,进而分析出地震-地质综合研究技术与方法的发展趋势。

断陷盆地岩性油气藏快速勘探的实用地质—地震相结合配套技术——以塔南凹陷为例

陆相断陷盆地岩性圈闭目标的快速识别和优选,需要先进地质理论指导与地震技术应用两方面的有机结合。本文通过对塔南凹陷岩性油气藏快速勘探过程中使用的地质理论和地震技术进行总结,建立了一套复杂断陷盆地岩性油气藏快速探明储量规模的实用地质一地震配套技术系列。在岩性油气藏勘探程度不断加深的过程中,综合采用构造分析、层序分析、相带分析和成藏分析等地质分析方法进行指导,配合使用精细构造解释、地震多属性分析、井—震约束下的拟声波波阻抗反演等地震技术,实现岩性圈闭的"定背景、定层系、定区带和定目标",有效地解决了塔南凹陷岩性油藏勘探中遇到的地质难题,在较短的时间内实现了岩性油藏勘探的突破和基本探明。这一技术系列对同类断陷盆地岩性油气藏的勘探具有重要的借鉴和指导意义。

地震-地质综合储层预测技术在乌石A构造沉积微相研究中的应用

乌石A构造流沙港组三段沉积时期发育大型扇三角洲相沉积,其中优质储层为扇三角洲水下分流河道砂岩,因此,重点研究该区沉积微相特征,落实优质储层的发育规律及分布趋势是实现油气突破的关键。设置了地震-地质综合储层预测技术对沉积相进行精细研究,该方法结合了地质、地震和测井三方面的资料,从沉积相出发,以沉积相控制反演结果,最终引出精细的沉积相模式,实现了地震和地质的有机融合。该方法在乌石A构造区取得了有效成果,通过对流三段水下分流河道进行精细刻画,落实了储层"甜点"发育区,提出的井位部署建议钻探之后均钻遇优质储层,扩大了储量规模,为乌石A构造立架建产打下了坚实的基础。

地震-地质导向技术在盆缘复杂构造带的应用——以南川区为例

南川页岩气田位于川东南盆缘构造带,目标层系五峰组—龙马溪组经过多期构造运动改造,地层变形强烈,断裂、褶皱发育,地层产状变化剧烈,水平井的地质导向工作难度大。为保证水平井顺利入窗,提高靶窗钻遇率,本文以地震-地质一体化导向技术为研究目标。建立了层控、断控、井控的“三控”特色速度建模技术,得到较为可靠的深度域数据体。以深度域地震数据为基础,建立工区构造模型、地质模型,立体把控目的层空间展布形态,优化了靶点深度和水平段地层产状的预测方法。综合分析认为,地震-地质导向技术在水平井精准着窗、靶窗平稳穿行等导向关键环节均呈现了良好的指示意义。是复杂构造带油气效益勘探开发行之有效的技术方法,值得在同类型区块推广应用。

石油地震地质学研究新进展——“2011年石油地震地质学学术研讨会”侧记

文中综述了当前石油地震地质学研究的新动向、新进展,包括地震沉积学、地震储层学及地震成藏学等方面。指出地震-地质一体化的研究思路及方法在当前油气勘探实践中发挥了重要作用,尤其是针对陆相砂泥岩薄互层的砂体勘探中,人们在地震沉积学(寻找砂体)—地震储层学(确定有效砂体)—地震成藏学(发现油气藏)的研究道路上取得了显著成果。文中还对石油地震地质学的未来发展提出了展望。

塔中中西部地区鹰山组“串珠状”反射地震地质特征及主控因素分析

塔中中西部地区在地震剖面上常见"串珠状"地震反射,通过对常规地震剖面的剖析,可将研究区"串珠状"反射细分为强"串珠"反射和弱"串珠"反射。两者的区别在于反射能量的强弱,在地震剖面上两类反射具有一定的相似性。从地质上解析,两者也具有类似的成因和控制因素,其分布主要受到了构造断裂、风化壳岩溶及埋藏岩溶的影响。通过对塔中中西部地区鹰山组"串珠状"反射地质特征的描述,建立起该区单井地震-地质模型,并对研究区形成"串珠状"反射的控制因素进行分析,明确了"串珠状"反射的发育分布模式。

松辽盆地火山岩相地震特征及其与控陷断裂的关系

在松辽盆地营城组火山岩中识别出5相15亚相。控陷断裂控制火山岩相分布，火山喷发中心沿大断裂呈串珠状分布。靠近深断裂一侧从下到上相序为喷溢相-侵出相／火山通道相，远离深断裂一侧相序为喷溢相-爆发相-喷溢相或火山沉积相；横向上相序为火山通道／侵出相-喷溢相-爆发相-火山沉积相。喷溢相呈席状披盖或丘状，中弱振幅，中频，连续性中-差，见断续渡状反射，横向宽约6～10km，纵向厚约200-400m。爆发相呈楔状或透镜状、中强振幅、中低频、连续性差-中，横向宽约6～8km，纵向厚约100～200m。而火山通道相和侵出相呈（陡）丘状、中强振幅、低频、杂乱反射，仅分布在火山口附近，横向宽多小于2km，纵向厚约100-200m。火山沉积相呈上超充填，中强振幅，中频，连续性好，分布在低洼地区，横向宽约4～7km，纵向厚约50～150m。

The algorithm of 3D multi-scale volumetric curvature and its application

To fully extract and mine the multi-scale features of reservoirs and geologic structures in time/depth and space dimensions, a new 3D multi-scale volumetric curvature （MSVC） methodology is presented in this paper. We also propose a fast algorithm for computing 3D volumetric curvature. In comparison to conventional volumetric curvature attributes, its main improvements and key algorithms introduce multi-frequency components expansion in time-frequency domain and the corresponding multi-scale adaptive differential operator in the wavenumber domain, into the volumetric curvature calculation. This methodology can simultaneously depict seismic multi-scale features in both time and space. Additionally, we use data fusion of volumetric curvatures at various scales to take full advantage of the geologic features and anomalies extracted by curvature measurements at different scales. The 3D MSVC can highlight geologic anomalies and reduce noise at the same time. Thus, it improves the interpretation efficiency of curvature attributes analysis. The 3D MSVC is applied to both land and marine 3D seismic data. The results demonstrate that it can indicate the spatial distribution of reservoirs, detect faults and fracture zones, and identify their multi-scale properties.

Preventing and Limiting Exposure to Geo-Hazards:Some Lessons from Two Mountain Villages Destroyed by the Wenchuan Earthquake

This paper examines the experiences of two mountain communities- Yinchanggou and Donghekou in the Wenchuan earthquake of May 12, 2008, where Yinchanggou's tourism economy and natural park system was destroyed and Donghekou was buried by a landslide. We conducted research surveys on both the communities, interviewing survivors and local officials, and observed the destruction/reconstruction, geological, and living conditions. We suggest that protracted educational processes be put into place so that mountain communities possess a knowledge base to consider long-term disaster prevention when building the economy in the fragile and geo-hazardous conditions of the Longmenshan. The Donghekou Earthquake Ruins Park is an exemplar of turning disaster into sustainable, safe development for small mountain villages.

Exploration and Study on Deep Crust Structural Characteristics in the Jiashi-Artux Seismic Region

The data from two deep seismic sounding profiles was processed and studied comprehensively. The results show that crust_mantle structures in the investigated region obviously display layered characteristics and velocity structures and tectonic features have larger distinction in different geological structure blocks. The boundary interface C between the upper and lower crust and Moho fluctuate greatly. The shallowest depths of C (30 0km) and Moho (45 5km) under Jiashi deepen sharply from Jiashi to the western Kunlun mountain areas, where the depths of C and Moho are 44 0km and 70 0km, respectively. The higher velocity structures in the Tarim massif determine its relatively “stable” characteristics in crust tectonics. The phenomenon in the Jiashi region, where the distribution of earthquake foci mostly range from 20km to 40km in depth, may infer that the local uplift of C and Moho interface, anomalously lower velocity bodies and deep large faults control earthquake occurrence and seismogenic processes in the Jiashi strong earthquake swarm.

Analysis on Dam-Breaking Mode of Tangjiashan Barrier Dam in Beichuan County

Tangjiashan landslide is a typical high-speed consequent landslide of medium-steep dip angle. This landslide triggered by earthquake took place in about semi-minute. The relative sliding displacement is 900 meters, so average sliding speed is about 30 meters per second. The longitudinal length of barrier dam which is formed by high-speed landslide along river is 803.4 meters; and maximum width crossing river is 611.8 meters. And its volume is estimated about 20.37 million steres. Through detailed geological investigation of the barrier dam, together with early geological information before earthquake, geological structures of the barrier dam and its stability of upstream and downstream slopes are studied when water level reaches different elevations in condition of continual after shocks with seismic intensity of 7 or 8 Richter scale. On this basis, dam-breaking mode of barrier dam is discussed deeply. Thereby, analytic results provide significant guidance and advices to front headquarters of Tangjiashan barrier dam, so that some proper engineering measures can be implemented and flood discharge can be carried out well.

Anomalous astronomical time-latitude residuals:a potential earthquake precursor

The geophysical mechanism behind astronomical time-latitude residuals （ATLR） are discussed. The photoelectric astrolabe at Yunnan Observatory （YO） observed apparent synchronous anomalous ATLR before the Wenchuan M8.0 earthquake （EQ） in May 12, 2008 and the Lushan M7.0 EQ n April 20, 2013. We compared the ATLR from the YO photoelectric astrolabe and EQ data since 1976. Anomalous ATLR was observed before several strong EQs in the Yunnan Province. We believe the photoelectric astrolabe can be used to predict strong EQs and the anomalous ATLR are a potential EQ precursor.

GiT-based structural geologic feature analysis of the southern segment of Longmenshan fault zone for earthquake evidence

The Longmenshan fault is a thrust fault which runs along the base of the Longmen Mountains in Siehuan province, southwestern China. The southern segment of the fault had two distinct responses to the Ms 8 Wenehuan and Ms 7 Lushan earthquakes. This study determines characteristics of the structural geology of the Longmenshan fault to evaluate how it influenced the two aforementioned earthquakes. This research was done within a Geo- information Technologies （GiT） environment based on multi-source remote sensing and crustal movement data extracted from the Global Positioning System （GPS）. The spatial distribution of the southern segment of the Longmenshan fault zone was comprehensively analyzed to study both earthquakes. The study revealed that the Wenehuan and Lushan earthquakes occurred on two relatively independent faults. In addition, there was a nearly constant-velocity crustal movement zone between the two epicenters that probably had a compressive stress with slow motion. Furthermore, the central fault and a mountain back fault gradually merged from north to south. The Lushan earthquake of the Wenchuan earthquake. was not an affershock The research showed that fault zones within 30-50 km of State Highway 318 are intensive and complex. In addition, crustal movement velocity decreased rapidly, with a strong multi-directional shear zone. Thus, activity in that zone was likely stronger than in the northern part over the medium to long term.

Study on Active Faults and Seismogenic Structure for the 1989 Batang M6.2～6.7 Earthquake Swarm in the Litang-Batang Region of West Sichuan,China

Fault structures in the Litang-Batang region of West Sichuan are mainly sub-longitudinal and a set of NNE- and NW-trending conjugate shear fracture zones is developed. In this paper, emphasis is put on explaining the movement patterns along the fault structures in the region since the late Pleistocene-Holocene on the basis of detailed interpretation of TM satellite images and aero-photos in geomorphologic aspect of active structures. The sub-latitudinal shortening rate along the sub-longitudinal Jinshajiang fault zone is determined to be 2～3mm/a since the late Quaternary, the horizontal dextral slip movement rate along the NNE-trending Batang fault is 1.3～2.7mm/a on average, and the horizontal sinistral slip movement rate along the NW-trending Litang fault is 2.6～4.4 mm/a on average. The general status of the recent crustal movement in the region and the regularities of block motion caused by it are analyzed in combination with data of geophysical fields, focal mechanism solutions and GPS measurements. The occurrence of the 1989 Batang M6.2～6.7 earthquake swarm is suggested to be the result of tensional rupture along the sub-latitudinal normal fault derived from the conjugate shearing along the NNE-trending Batang and the NW-trending Litang faults. It reveals a typical seismic case produced by normal faulting in a compressional tectonic environment.

Relocation of Earthquakes in the Northeastern Tianshan Mountains Area and Improvement of Local 1-D Crustal Velocity Model

We apply three methods to relocate 599 earthquake events that occurred from August 2004 to August 2005 in the northeastern Tianshan Mountains area ( 85°30' ～ 88°30'E,43°00' ～ 44°40' N ) by using travel times recorded by regional seismic network and 10 portable seismic stations deployed around the Urumqi city. By comparing the reliability of different results,we determined a suitable location method,and an improved 1-D crustal velocity model of the study area. The uncertainty of earthquake location is significantly reduced with combined data of seismic network and portable stations. The relocated events are clearly associated with regional tectonics of the northeastern Tianshan Mountains area, and are also in agreement with the existence of active faults imaged by deep seismic reflection profile. The relocated seismicity discovers some potential traces of buried active faults,which need to be validated further.

Sands modeling constrained by high-resolution seismic data

In the phase of field evaluation, the changing of interwell reservoir may be out of control if the geological model was built only on well data due to few existing wells. The uncertainty of the interwell reservoir interpolation based only on well data can be decreased by comprehensive utilization of geological, logging and seismic data, especially by using highly relative seismic properties from 3D seismic data adjusted by well point data to restrict interpolation of geological properties. A 3D-geological model which takes the sand body as the direct modeling object was built through stacking the structure, reservoir and water/oil/gas properties together in 3D space.

The Activity of Liaocheng-Lankao Buried Fault During the Quaternary —An Important Buried Active Fault in the Eastern China Plain

On the basis of locating by the geochemical prospecting, shallow seismic sounding, drilling, geological profiling, and neogeochronological dating, we first found out the dislocation amount along the Liaocheng-Lankao buried fault since the Quaternary and the age of its latest activity phase and determined that the upper break point by the fault dislocation reaches 20 m below the surface. The latest activity phase was in the early Holocene and the fault is a shallow-buried active fault. An average dislocation rate along the fault is 0.12 nun/a since the Quaternary. Thus, it is a buried active fault with intermediate to strong movement strength in the eastern China.

Geo-engineering Lessons Learned from the 2008 Wenchuan Earthquake in Sichuan and Their Significance to Reconstruction

The 2008 Wenchuan earthquake in Sichuan of China was the result of quake-triggering along an active several hundred-kilometer-long fault. The subsequent landslides and debris flow geohazards are dominating factors in planning post-disaster recovery and rebuilding. This paper presents recommendations for coping with large-scale geohazards and disasters. It is essential to establish a national emergency management system for huge scale catastrophe and earthquake precursor identification. Town construction must be kept away from active faults, especially to improve town safety in areas with high risk of seismic and geological hazards, and it is important to improve geohazard investigation and remediation for mountain areas that have become loosened by earthquake activity. Geological factors must be better understood to reduce direct and secondary risks and effects of earthquakes. Site selections for public relocation require clear and informed analysis of geological and social risk reduction, so that relocation, infrastructure reconstruction, and commemorative relic-sites can be protected.