井震结合井间等时地层对比方法及其应用

井间地层对比是油气勘探开发的重要内容.由于测井资料的井间对比存在穿时问题,因此提出一种井震结合的等时地层对比方法.从岩心资料出发,利用岩心资料对测井资料进行刻度,并充分利用现代测井新技术,对测井资料进行岩相、沉积(微)相划分和层序地层分析.通过合成地震记录与层位标定,把单井分析结果标注到地震剖面上去,确定地震反射同相轴的地质意义.分别利用测井资料和地震资料确定岩相、沉积相以及层序地层特征,通过层位标定后,使得这些特征在剖面上和空间上达到一致来保证标定结果的准确性.在具有等时意义的地震强同相轴的控制下,参考约束地震反演剖面,根据高分辨率层序划分结果完成井间等时地层对比.这样的对比保证了井间对比的等时性,又确定了地震反射同相轴的地质意义,使测井、地震、地质三者紧密结合.这一方法对于建立正确的地层模型具有重要的指导意义.通过在胜坨油田某区块的实际应用,取得了良好的效果.     

基于地震沉积学方法的沉积相研究--以涠西南凹陷涠洲组三段为例

探讨地震沉积学方法在陆相薄互层的沉积相研究思路。地震沉积学主要是利用三维高精度地震资料来研究沉积岩及其形成过程,提高分辨率处理和分频解释有利于建立高频层序地层格架,等时地层切片可以用来约束划分最小等时地层单元。90°相位转换使地震同相轴具有岩性意义,可以用来刻画薄层砂体的形态及分布特征。优选能反映砂体形态的属性与反射波形特征,并结合物源方向、沉积体系类型来编制精细的沉积相分布图。以涠西南凹陷古近系涠洲组三段地层为例,开展地震沉积学方法的沉积相研究。识别并确立了研究区内7砂组最小等时地层单元,利用东西方向物源特征及砂体形态、90度相位转换地震振幅属性、波形特征,准确的勾画出7砂组以东、西两侧向湖盆推进的辫状河三角洲为规律的沉积相图。     

准噶尔盆地彩南地区石树沟群地震层序划分与层…

从地震资料入手，根据某些古凸起部位石树沟群内部存在的削截、上超、下超等不整合反射，将彩南地区石树沟群划分３个地震层序，通过区域追踪以及钻井和露头资料的综合分析，发现这３个地震层序分别与头屯河组、齐古组和喀拉扎组３个岩石地层单元相对应，头屯河组顶界的不整合系构造抬升剥蚀所形成，属构造成因，齐古组顶界的不整合系丘形侧积作用所形成，属沉积成因，地震相分析表明这３个层序（组）为３期物源来自北北东向克拉美丽     

准噶尔盆地彩南地区石树沟群地震层序划分与层序地层学解释

从地震资料入手,根据某些古凸起部位石树沟群内部存在的削截、上超、下超等不整合反射,将彩南地区石树沟群划分为3个地震层序。通过区域追踪以及钻井和露头资料的综合分析,发现这3个地震层序分别与头屯河组、齐古组和喀拉扎组3个岩石地层单元相对应。头屯河组顶界的不整合系构造抬升剥蚀所形成,属构造成因,齐古组顶界的不整合系丘形侧积作用所形成,属沉积成因。地震相分析表明这3个层序（组）为3期物源来自北北东向克拉美丽山的洪积扇沉积,其地层发育和沉积相特征受构造、物源和古气候3大因素的控制。在地震资料所揭示出的石树沟群内部和顶界不整合面附近及某些丘形、透镜形沉积体中,存在多种可能的地层圈闭。     

地震沉积学在川东北YB地区沉积相分析中的应用

将地震沉积学理论应用于川东北YB地区陆相须家河组二段沉积相分析。以低频层序界面为约束条件,采用三维地震相位展开技术建立高频层序地层格架;利用三维Wheeler变换技术自动拉平高分辨层序地层格架的地震同相轴,建立等时年代地层格架,将地震数据体转换为年代地层数据体;在此基础上,提取具有等时意义的年代地层切片进行沉积相分析。结果表明:该方法能直观地反映沉积体的几何形态、展布规律、纵向演化和平面变迁等特征,对后续的勘探开发具有指导意义。      

地震沉积学的概念、方法和技术

简单地讲,地震沉积学是应用地震信息研究沉积岩及其形成过程的学科,它是继地震地层学、层序地层学之后的又一门新的边缘交叉学科。其研究内容、方法和技术与地震地层学、层序地层学和沉积学等其他学科都有所不同,地震沉积学最大的理论突破在于对地震同相轴穿时性的重新认识。但它是沉积学的发展而不是替代,地震沉积学研究要以地质研究为基础,在沉积学规律的指导下进行。90°相位转换、地层切片和分频解释是地震沉积学中的三项关键技术。相位转换使地震相位具有了地层意义,可以用于高频层序地层的地震解释;地层切片是沿两个等时界面间等比例内插出的一系列层面进行切片来研究沉积体系和沉积相平面展布的技术;基于不同频率地震资料反映地质信息的不同,采用分频解释的方法,使得地震解释结果的地质意义更加明确。      

地层切片穿时现象对地震属性的影响

结合实际地震资料,采用以同相轴(波峰相位)为中心上下一个视周期内(穿时半个视周期)跳跃解释层位、以同相轴为中心上下3/2个视周期内(穿时3/4视周期)跳跃解释层位和严格按照同相轴(波峰相位)解释层位,并以解释出的层位为顶约束,以另一自动追踪同相轴解释的层位为底约束,内插建立层段地层切片;通过对不同方式制作的地层切片进行对比,研究了穿时对属性地层切片的影响。研究发现:轻微穿时对属性地层切片有一定的影响,但对地层切片上岩相分布的整体态势影响不大;瞬时相位和振幅瞬时值相关性不明显;当穿时超过3/4视周期时,振幅瞬时值属性地层切片上岩相分布的整体态势将受到很大影响,穿时程度越大,属性切片受到的影响也越大;穿时对属性地层切片的影响与时窗大小和属性本身的特性有关,时窗越小,影响越明显;与瞬时属性相比,切片属性为时窗内统计类属性时,穿时对属性地层切片的影响较小。     

珠江口盆地恩平凹陷古近系恩平组地震沉积学研究

根据珠江口盆地恩平凹陷高精度的三维地震和钻井等资料,将古近系恩平组分为3个三级层序PSQ1、PSQ2、PSQ3。基于建立的等时层序地层格架,开展了岩石物理分析、分频处理、90°相位转换和地层切片等一系列的地震沉积学分析,取得了以下认识:1建立了不同岩性与波阻抗的对应关系,强振幅对应于砂岩,弱振幅对应于泥岩;2地层切片指示研究区西部多为条带状分布的振幅异常,东北部为朵叶状分布的振幅异常;3恩平凹陷北部PSQ1、PSQ2层序发育扇三角洲相,PSQ3层序发育辫状河三角洲相;恩平凹陷西部在整个恩平组沉积时期仅发育辫状河三角洲相。     

和什托洛盖盆地中下侏罗统地震层序地层研究

开展地震层序地层学研究对含煤盆地层序地层格架建立、沉积体系划分和整体煤层对比具有重要意义。地震层序解释以地震剖面为基础,识别不同级别的不整合面及与之对应的界面,并进行横向对比追踪与闭合,建立等时地层格架。本文基于新疆西北部和什托洛盖盆地丰富的地震剖面,结合钻井标定和测井解释,开展对和什托洛盖盆地中下侏罗统地震层序地层特征研究,结果表明,和什托洛盖盆地中下侏罗统可识别出2个二级层序界面、6个三级层序界面,并划分为1个二级层序,7个三级层序;其中,八道湾组可划分为3个三级层序,三工河组和西山窑组各划分为2个三级层序。SQ1高位体系域、SQ6湖扩体系域及SQ7高位体系城普遍发育煤层,主要煤层位于SQ7高位体系域。     

地震剖面线性化处理和沉积相解释

用黑白同相轴的时深地震剖面来解释沉积相和研究层序地层时，由于分辨率低，难于正确分辨反射结构和外部几何形态。地震剖面经过线性化处理后，将黑白同相轴变成线状剖面图，相对提高了剖面的分辨率，使研究与解释更加清晰，内容更加丰富。作出若干沉积相和火山相的解释模式。     

Late Quaternary coastal and inner shelf stratigraphy, Apalachicola Delta region, Florida

Since the beginning of the Tertiary the sedimentology of the Gulf of Mexico Basin has been dominated by the depositional activity of the Mississippi River. The sedimentologic influence of the Mississippi diminishes with distance east or west of the Louisiana shelf, however. The Texas and northwest Florida shelf margins, for example, are characterized by a series of smaller deltas. In the inner and mid-shelf areas of these regions the near-surface sedimentary units include infilled stream channels and small deltas. Such features are commonly observed in sub-bottom seismic records from the middle and inner shelf of the northeastern Gulf, along the Apalachicola River coast of northwest Florida.

The Apalachicola River is the principal source of clastic sediment to the northeastern Gulf of Mexico. During the late Holocene virtually all of the river's sediment load has been deposited in the modern Apalachicola Delta and in the river's estuary, Apalachicola Bay, which has been filling rapidly. During late Quaternary lowstands, prior to the development of the modern estuary, the river traversed the present-day inner and mid-shelf, incising a network of channels. Based on seismic records, many of these buried shelf channels were considerably larger than their modern counterparts.

During lowstands the Apalachicola River also deposited coarse sediment on the shelf as deltaic and associated river-mouth sediments. These deposits comprise the modern near-surface sediments of the inner and middle shelf. An investigation of subsurface sedimentary features observed in seismic profiles provides details on the late Quaternary development of the northeastern Gulf of Mexico shelf. Seismic reflection profiles obtained on the inner and mid-shelf regions of northwest Florida reveal an approximately 50 m thickness of late Quaternary sediments, comprised of two and sometimes three discrete clastic sequences. Two lower fluvial sequences total as much as 40–50 m in thickness. A transgressive marine sand deposit overlies the older features in some places, varying in thickness from 0 to 5 m. Identification of seismic facies, combined with stratigraphic data from a suite of coastal boreholes, enables correlation of offshore seismic stratigraphic units with late Tertiary and Quaternary coastal stratigraphy.     

冲绳海槽西部陆坡第四纪沉积地层划分

冲绳海槽西部陆坡是认识深海斜坡沉积的重要区域。通过对高分辨率地震资料的精细解释,结合已有的研究成果,在冲绳海槽西部陆坡海底以下识别出4个主要的地震层序界面,相应地划分出四个主要地震层序,各层序分别对应全新世沉积层(Q4)、晚更新世沉积层(Q3)、中更新世沉积层(Q2)和早更新世沉积层(Q1)。从陆坡上部往下由斜交前积反射结构过渡到杂乱的反射结构,在地震剖面上可识别出杂乱的丘形反射单元,是滑塌体和重力流沉积的典型地震反射特征,反映出一种高能的、极不稳定的沉积环境。海槽轴部以平行-亚平行的地震反射特征为主,显示了稳定的深海-半深海的沉积环境。地震反射结构的多样性反映了冲绳海槽西部陆坡沉积环境的复杂性和沉机作用类型的多样性,沉积地层结构是多种因素共同作用的结果。东海陆架和冲绳海槽发育相同的第四纪地层垂向序列,同时冲绳海槽西部陆坡与东海陆架第四纪沉积层在层序界面、沉积层厚度、变形程度和产状等方面存在着差异,单靠地震资料来进行两个地区的地层对比存在着不确定性。     

Effects of low- to high-angle normal faults on sedimentary architectures in the Eocene Wenchang Formation,Enping Sag,Pearl River Mouth Basin,South China Sea

The effects of low- to high-angle (>30°) normal faults on sedimentary architectural units in the Eocene Wenchang Formation, Enping Sag, Pearl River Mouth Basin (PRMB), South China Sea were investigated utilising a high-quality 3D seismic data set and restored paleogeomorphology. It has been shown that sequence stratigraphic units and sedimentary architecture are significantly controlled by the low- to high-angle normal faults. The Wenchang Formation, a second-order sequence, can be subdivided into two para-second-sequences (the Lower and Upper Wenchang sequences, E₂W^L and E₂W^U) and seven third-order sequences (from base to top: SQ1～SQ7). The low-angle fault confined sequence architecture of the Wenchang Formation is mainly characterised by lateral stacking with the ratio of the vertical subsidence (V) to horizontal slip (H) being reduced from 1/2 for E₂W^L to 1/6 for E₂W^U. In contrast, the high-angle fault confined sequence is characterised by vertical stacking with the ratio of V/H close to 1 for sequences SQ1 to SQ7. In the 3D seismic area, the features of sediment-dispersal pattern were interpreted based on an integrated analysis of paleogeomorphology, seismic reflection characteristics, stratal thickness distribution and multiple attribute clustering. The results show that the large-scale fan delta, belt-shape lacustrine deposit and bird-foot braided delta systems mainly developed in the low-angle fault confined sequences, whereas small-scale fan delta, rhombus-shaped lacustrine deposit and lobe-shaped braided delta systems inherited tectono-sedimentary architectures in the high-angle fault confined sequences.     

地震射线追踪法的模型研究与应用

论述了用数字方法设计出地层弹性波速度模型的原理和方法,阐述了地震射线追踪法的算法并用其对数字模型的反射、折射波时距曲线做了计算,通过实例分析了复杂速度结构与地震剖面的对应关系,可指导解释人员根据实际地质情况任意设计地层模型进行计算,很快得出结果。     

Seismic Sequence in Carbonate Rocks By Vibrational Liquefaction1

Abstract On the basis of the records of strong seismic events taking place in soft carbonate sediments, a new seismic sequence system of vibrational liquefaction is established, which consists of a series of units, such as escaped structure of micrite veins and liquefied deformation formed in the period of seismic liquefaction, land subsidence structure after liquefaction, tsunamic hummocky and turbidite produced by seismic events, This sequence is a generalization and summation of field observation in vast areas, which shows the whole process of a strong seismic event and provides an unified theoretical explanation. The pattern of the seismic sequence by vibrational liquefaction provides one of correlation standards for geologists in the field to discriminate events in carbonate sequences. Based on the pattern of seismic sequence, the authors first advance a new conception of the Palaeo - Tanlu (Tancheng - Lujiang) Zone and discuss primarily its geological significations.     

Harmonic Analysis of Sedimentary Cyclic Sequences in Kansas, Midcontinent, USA

Several stratigraphic sequences in the Upper Carboniferous (Pennsylvanian) in Kansas (Midcontinent, USA) were analyzed quantitatively for periodic repetitions. The sequences were coded by lithologic type into strings of datasets. The strings then were analyzed by an adaptation of a one-dimensional Fourier transform analysis and examined for evidence of periodicity. The method was tested using different states in coding to determine the robustness of the method and data. The most persistent response is in multiples of 8–10 ft (2.5–3.0 m) and probably is dependent on the depositional thickness of the original lithologic units. Other cyclicities occurred in multiples of the basic frequency of 8–10 with persistent ones at 22 and 30 feet (6.5–9.0 m) and large ones at 80 and 160 feet (25–50 m). These levels of thickness relate well to the basic cyclothem and megacyclothem as measured on outcrop. We propose that this approach is a suitable one for analyzing cyclic events in the stratigraphic record.     

南海北部白云凹陷深水区SQ13.8深水扇砂体识别与分布研究：以SF-5为例

珠江口盆地白云凹陷在继“白云运动”之后,在13.8 Ma发生了一次大规模的海退事件,海平面下降至陆架坡折带附近,三角洲向盆地方向推进最远,十分有利于深水扇的发育。通过深水陆坡区B6井及陆架边缘多口井的井震标定,结合钻井、测井分析,系统总结出具有厚度较大（20~40 m）、以泥质粉砂岩为主的斜坡扇储层,对应低频、短轴、强振幅的地震反射特征,在负极性显示的地震剖面上,表现为强波谷地震响应。层序地层格架分析认为工区处于SQ13.8“陆架边缘三角洲—沉积过路区—斜坡扇”的沉积环境,并在层序格架的约束下,通过合成地震记录建立井-震关系,对斜坡扇区第5套砂层组（SF-5）进行储层识别与追踪解释,确定SF-5砂层为主体分布在陆架坡折带外侧陆坡区的丘状体,平面形态似帚状或朵叶状,具有斜坡扇的特征,其优质储层主要分布在工区的中部-西部地区,呈NW-SE方向条带状展布。     

Structure of a silica diagenetic transformation zone: the Gjallar Ridge,offshore Norway

Three‐dimensional seismic data from the Gjallar Ridge were used together with X‐ray diffraction data, scientific boreholes and wireline logs to analyse the seismic structure of a silica diagenetic transformation zone. The following features were identified: (i) an interval some 150 to 300 m thick that contains anomalously high‐amplitude reflections; (ii) a strong reflection event at the top of this interval which cross‐cuts stratigraphy, interpreted as the transformation boundary between opal‐A‐rich and opal‐CT‐rich sediment; (iii) amplitude variations on stratigraphic reflections within the interval, attributed to variations in the proportions of opal‐A and opal‐CT; and (iv) a second, deeper, cross‐cutting reflection event within the interval, interpreted as the transformation boundary between opal‐CT‐rich and quartz‐rich sediment. The base of the interval containing the anomalously high‐amplitude reflections is interpreted as a stratigraphic reflection demarcating the base of the silica‐rich strata. On a stratigraphic reflection within the interval of high amplitudes, roughly circular regions of anomalously high amplitude with diameters of 0·8 to 2·5 km are separated by lower amplitude regions. This pattern is similar to the cells previously identified at the opal‐A to opal‐CT transformation boundary and probably results from more complete transformation of opal‐A to opal‐CT. All of these observations provide the first recognition from seismic data that silica diagenetic transformations are not always narrow boundaries represented by single cross‐cutting seismic reflection events, as implied previously, but can be heterogeneous and hundreds of metres in thickness, as observed at outcrop.     

Seismic Sequence in Carbonate Rocks By Vibrational Liquefaction

On the basis of the records of strong seismic events taking place in soft carbonate sediments, a new seismic sequence system of vibrational liquefaction is established, which consists of a series of units, such as escaped structure of micrite veins and liquefied deformation formed in the period of seismic liquefaction, land subsidence structure after liquefaction, tsunamic hummocky and turbidite produced by seismic events, This sequence is a generalization and summation of field observation in vast areas, which shows the whole process of a strong seismic event and provides an unified theoretical explanation. The pattern of the seismic sequence by vibrational liquefaction provides one of correlation standards for geologists in the field to discriminate events in carbonate sequences. Based on the pattern of seismic sequence, the authors first advance a new conception of the Palaeo-Tanlu (Tancheng-Lujiang) Zone and discuss primarily its geological significations.