利用地震波特征参数解释断层落差

断层落差是断层解释的一项重要内容。通过研究断层与地震波之间的关系,提出了一种利用地震波特征参数解释断层落差的方法。通过对实际资料的解释,证明该方法是可行的。     

利用地震波特征参数解释断层落差

断层落差是断层解释的一项重要内容。通过研究断层与地震波之间的关系,提出了一种利用地震波特征参数解释断层落差的方法。通过对实际资料的解释,证明该方法是可行的      

直接利用多元地震特征参数识别微小断层

在地震地质条件较好的地区，２Ｄ地震勘探能较可靠查明落差≥１０ｍ的断层。而正在兴起的３Ｄ地震勘探，可较可靠查明落差≥５ｍ及延伸更短的断层。为了能准确地识别微小断层，除人机联作解释外，目前经常借助计算机，采用模式识别及神经网络的方法。本文介绍了一咱直接利用地震特征参数计算支隶属度，以识别微小断层的新方法，无需建立标准模式或提供训练样本。通过对实际资料的处理解释，证明该方法是可行的。     

应用概率模型定量预测断层的数量和规模

地层中的断层实际存在的数目远比构造图上的多。影响断层制图的因素除断层系统本身的复杂性外，主要受地震分辩率和地震测线网格密度的控制。讨论了地震网格密度对断层检测的影响，提出了采用Ｈｏｒｖｉｔｚ－Ｔｈｏｍｐｓｏｎ概率模型估计一个总体中断层的数目和规模，给出了该模型的计算公式，并以计算机模拟的断层总体为例介绍该方法在预测断层特征中的实际应用。     

模糊概率法检测小断层的研究及在龙东区的应用

讷发辨三维地震探已经成为煤矿采区生产补充勘探的主要手段,它的基本任务是通过人机联作解释查明落差≥５ｍ的断层。本文采用模糊概率法检测小断层,通过对龙东矿辅块设三维地震探区的研究与检测,可以将小断层落差的探精度提高了３ｍ左右。检测出的小断层经矿方验证,精度与准确度较高,效果明显。     

利用等高线拟合法预测隐伏断裂构造

论文以东庞煤矿２２２０工作面上巷实见的落差为３２米的隐伏大断怪为例，用祥实的数据资料和严密的理论推导；阐明了在巷道是过程中，用等高线拟合法分析和预测隐伏断裂构造的方法，并首次提出了用等高线的拟合程度定量预测断层落差的可行性。同时，笔者自计算机软件对断层的相关节理进行统计优选，以达到定量预测断层产状的目的。二者的有机结合对掘进巷道断裂构造超前预测的定量化研究有较好的指导意义。     

CSAMT法在断层含水性评价中的应用

在河南省平顶山地区小屯正断层上进行勘查,采用CSAMT法对落差较大断层的含、导水性进行了测量,结果表明该法不仅可以有效控制断层的空间位置,而且可以定性判断断层的富水性。说明CSAMT法的应用在断层含水性评价方面有积极的效果。     

良庄煤矿51101W工作面突水机理

新汶矿业集团良庄煤矿51101W工作面因底板突水导致工作面被淹。通过水质分析,判定突水水源是奥陶系灰岩岩溶水。根据工作面附近的地质构造推断,突水通道为延伸到奥陶系与石炭系不整合面的铲状滑动断层(该断层最大落差只有7 m左右)。结合工程实践指出,在该矿,根据断层落差来判断断层导水性的观点并不正确,并提出了“用断层落差(H)与其倾角(α)之比值(S)来说明断层对突水影响程度”的观点。      

复合煤层中夹矸对槽波探测解释断层落差的影响

槽波地震勘探技术在探测工作面内部断层、陷落柱发育情况、煤厚变化等方面已经取得较好的应用效果，现已成为井下地质构造探测的首选方法。但对于含夹矸的复合煤层地质构造的探测，槽波方法还存在一定的问题，为研究复合煤层中夹矸对槽波地震探测中断层落差解释的影响，通过建立不同的数值模型进行正演分析，并选取山西某矿复合煤层进行槽波探测试验。研究结果表明:复合煤层中的夹矸对槽波探测解释断层落差有较大影响，夹矸的厚度与煤层差异较小时，槽波探测解释断层落差时的单位煤厚标准应为复合煤层的总厚度；差异较大时，单位煤厚标准应为激发接收层的单一煤层厚度。研究结果可为槽波实际资料的解释、分析提供参考依据。      

生长断层活动强度定量研究的主要方法评述

目前,定量研究生长断层活动强度的主要方法有生长指数法、古落差法、断层活动速率法、(古)滑距法和断层位移—长度关系分析法等。在前人研究的基础上,对这些方法进行系统的补充和总结。从不同方法的提出、判别、前提假设、优缺点和关系对比等方面,进行介绍和评述。并通过实例分析,用生长指数法、古落差法、断层活动速率法和断层位移—长度关系分析法计算大张坨断层的活动强度,指出不同方法的优缺点。最后对生长断层活动定量研究方法的发展趋势进行了预测,认为生长断层活动定量研究向精度不断提高、多种方法综合运用、对断层活动演化研究更全面、揭示更多的地质和油气信息等方面发展。     

田岗断层产状的确定方法

搞清断层赋存状态对矿井安全生产至关重要。针对目前以范围表示方法确定断层产状存在精度不足的问题,山东崔庄煤矿通过在井下施工断层探孔,探明了田岗断层地质层位关系等情况,并运用平面投影法和矿体几何要素较准确地确定了田岗断层的产状要素,包括断层倾角、断层落差和断层走向等,从而取代了通常对断层产状较模糊的范围表示法。本研究方法原理简单,易于掌握,其计算结果比原有地质资料更加准确可靠。      

正断层断距纵剖面图及其运动学:概念模型与地质实例

断距纵剖面图 （T H图）是指以断层的垂直断距为横轴、以地层或地质年龄为纵轴所绘制的随地层或地质年龄所变化的断距分布图。断距纵剖面图为确定正断层类型、断层形成时间和断层的纵向演化史提供了一个简单迅捷的工具。概念模型表明,断距纵剖面图可以明确无误地区分出简单后沉积型正断层、后沉积拱顶拉张型正断层、同沉积生长型正断层及其复合型正断层。简单后沉积型正断层的断距不随地层年龄的变化而变化, 其断距纵剖面图为一垂直线段。后沉积拱顶拉张型正断层的断距随地层年龄的增大而减小并趋向零值,同沉积生长型正断层的断距随地层年龄的增大而增大,复合型正断层则具其组合型断距纵剖面形态。除简单后沉积型正断层外,断距纵剖面图中的最大断距点代表了该断层的起始形成年代。     

西藏错那-沃卡裂谷带中段邛多江地堑晚新生代正断层作用

遥感解译和地表调查结果显示, 位于西藏曲松县境内的邛多江盆地构成了藏南近南北向裂谷带最东端的错那-沃卡裂谷的中段。它是在该区近东西向逆冲构造带停止活动之后, 上地壳沿N108～115°E方向发生引张作用所形成的第四纪半地堑式断陷盆地。控制晚第四纪盆地发育的主边界正断裂带位于盆地西缘, 总体呈NNE走向, 向东倾, 长40 km左右。断裂活动位移测量和年代学测试结果表明, 该边界正断层带在5Ma左右就已开始活动, 总累计垂直位移量至少为2.6～2.8 km, 最小长期平均垂直活动速率约0.5mm/a。末次冰期盛冰期以来, 该断裂平均活动速率的最合理的估计值为1.2 ±0.6 mm/a。      

用高分辨率地震技术研究活动断层

基于重大工程前期区域工程地质勘查的需要,在华北平原北部XY地区进行了一次高分辨率P波三维地震和S波二维地震描述、刻画地下活断层的试验研究,取得了本地区浅、中、深不同深度的地震成果。其中F1断层是该区一条重要控制断层,其重、磁、电资料虽有微弱显示,但位置不准确,难以对其活动性进行评价。经过本次综合勘探后,落实了该断层的存在,并发现该断层在工区范围内的中部分裂成F1-1及F1两条断层,F1-1、F1断层在平面上呈北东向“Y”字型展布,断距在纵、横向都呈现显著的分段特征,其断距最小90m,最大可达300m。该次勘探所获纵波反射主频达120～150Hz,活动断层地震成象十分清楚。可见高分辨率三维地震与超浅层横波反射地震相结合,可有效评价活动断层,为防震减灾工程研究提供可靠信息。     

Damage zone and slip-surface evolution over μm to km scales in high-porosity Navajo sandstone, Utah

Detailed mapping of throw variations and deformation along two km-scale normal faults in the high-porosity Navajo sandstone, Utah, has been used to investigate fault growth in this lithology. The faults consist of one or more through-going, striated, slip-surfaces, accommodating the greater part of the offset surrounded by a damage zone consisting of deformation band clusters and short, unconnected slip-surfaces. In contrast to previous models for deformation in this lithology, we find that the nucleation of slip-surfaces begins where measurable throw is negligible and deformation bands are forming and increasing in number. The microstructure and porosity of deformation bands and slip surfaces are distinct and independent of the amount of offset that they accommodate, i.e. they represent different and yet contemporaneous deformation mechanisms. The point where measurable throw begins to accumulate (the fault tip) is marked by the first through-going connected slip-surface. Increase in throw towards the centre of the fault results in a three-dimensional strain field, producing orthorhombic structural geometries within the damage zone. We find that the total width of the damage zone increases as offset is accumulated. For these faults, the damage zone width is approximately 2.5 times the total fault throw.     

Scaling properties within the Gulf of Corinth, Greece; comparison between offshore and onshore active faults

The Gulf of Corinth, Greece, is a 110-km-long by 30-km-wide active graben displaying strong seismicity hosted both on north and south dipping normal faults. This complex fault pattern consists of two fault populations, offshore and onshore. The offshore fault population is investigated by densely arranged seismic reflection profiles during the last 20 years, whereas the onshore fault population displays spectacular and well exposed faults, delineated by high accuracy mapping. We analyzed fault length and throw, in order to study the scaling properties of 136 well-determined offshore and onshore faults and the comparison between the two datasets. We examined the statistical properties on both fault populations, in order to describe the role of segmentation in the growth of faults and the different stages of the evolution of the fault networks.Our results on power law relationships associated with the scaling properties of the fault zones in the Gulf of Corinth, suggest that both fault populations are bi-fractal, providing the initiation of a sature state in deformation. In addition, the vertical throw of faults shows that both fault populations have similar properties but different distributions below and above 5 km, respectively. Displacement–length ratios, show that faults larger than 9 km appear to accumulate throw without any dramatic change to their length. These observations combined with other geophysical studies within the Gulf, suggest that the characteristic fault lengths of 5 km and 9 km can be correlated to the crustal mechanical structure and the seismicity of the Gulf.     

Strain variation with progressive deformation in basement-involved trishear structures

Basement-involved structures associated with reverse, vertical and normal faults commonly involve non-parallel shear within a triangular deformation (trishear) zone located on the front limbs of the structures. Deformation within the trishear zone is characterized by shear gradients and an associated decrease in the dips of the beds in stratigraphically higher units. Geometric models suggest that the layer-parallel strain within the trishear zone depends on the type of fault (normal, reverse, or vertical), the dip and throw of the fault, the dip of the anticlinal or synclinal axial surfaces, and the distance of any unit above the initial tip of the trishear zone, located at the basement-sediment contact. At any given location, reverse faults typically show increasing layer parallel shortening, followed by decreasing layer parallel shortening and a transition to extension, with increasing throw. The transition from contraction to extension occurs at lower values of throw for stratigraphically lower units and also for faults with smaller dips. Vertical and normal faults exhibit increasing layer-parallel extension of all units with increasing throw, with larger extension for stratigraphically lower units. Experimental models suggest that the trishear zone can expand with increasing fault throw. The strain within the trishear zones is accommodated largely by secondary faults, which are rotated with progressive deformation. The strain variations in the experiments closely mimic those predicted by the geometric models for reverse, vertical, and normal faults.     

地质剖面图的计算机绘制技术

提出了一种地质剖面的计算机绘制技术－整体平移法，分层平移法，解决了剖面图形处理中两个关键问题，剖面上变倾角，变落差及任意切割交错关系的断层处理和地层曲线间的形态协调问题。