斯通利波在碳酸盐岩储层解释中的应用   总被引：1，自引：0，他引：1  

孔祥荣 《新疆地质》2005,23(3):296-299

在塔河油田碳酸特岩裂缝性储层中，采用声波全波列测井及偶极横波测井来获取丰富信息，主要成分波有纵波、横波、斯通利波，主要采用时域和频域2种信启、提取方法，来获得声波时差、频率和能量信息．其能量衰减和能量值的大小可以反映地层渗透性能，斯通利波能量的相对变化可用来定性划分渗透层，反射波能量反映渗透性地层的裂缝分布，为划分渗透层提供了良好的条件．  相似文献   

基于GIS的云南普朗斑岩铜矿床三维成矿预测   总被引：1，自引：0，他引：1  

王功文  郭远生  杜杨松  范玉华  郭欣  庞振山  陈建平 《矿床地质》2007,26(6):651-658

文章根据云南普朗斑岩铜矿床地质特征以及矿区72个见矿钻孔中8145个岩芯样品的铜含量分析数据,采用GIS空间分析技术和利用邻近距离统计分析方法,优化和提取了矿床定位预测所需点位的数据信息(包含三维空间坐标及其对应的铜含量数值)。在此基础上,选用反距离权重内插法,在比例尺1:10000的尺度上,确定了该矿区铜元素在海拔3171～4319m不同高度的空间分布状况,并利用3D-GIS的规则六面体成像技术和邻近采样点插值法,建立了该铜矿床含矿岩体(铜含量不小于0.2%)和铜矿体(铜含量不小于0.3%)的三维模型,确定含矿岩体和铜矿体的形态为"锥状体"。最后,在综合分析云南普朗铜矿床特征及其保存条件和剥蚀状况以及钻探资料和矿床三维空间特征的基础上,确定矿床的南西侧具有较好的找矿潜力,认为矿床的东、北两侧深部是有利的成矿远景区。  相似文献   

Correlations between the in situ acoustic properties and geotechnical parameters of sediments in the Yellow Sea,China     

《Journal of Asian Earth Sciences》2013

Knowledge about the marine sediment acoustic properties is a key to understanding wave propagation in sediments and is very important for military oceanography and ocean engineering. We developed a hydraulic-drived self-contained in situ sediment acoustic measurement system, and measured for the first time the in situ acoustic properties of sediments on 78 stations in the Yellow Sea, China, by employing this system. The relationships between the in situ measured acoustic properties and the onboard or laboratory determined geotechnical parameters were analyzed. Porosity was found to be the dominant factor in reducing velocity in a quadratic fashion; velocity showed an increment with bulk density and a decrement with mean grain size and clay content both with a nonlinear dependence; acoustic attenuation showed a bell-shaped correlation with porosity and mean grain size but reduced with clay content of the sediments. The attenuation results indicate that intergrain friction rather than viscous interactions between pore fluid and solid grains is the dominant loss mechanism in our marine sediments. The relationships established would be used to predict the geotechnical parameters from in situ measured acoustic properties and vice versa, as well as being an indicator of the seafloor processes, potential gas bubbles hazard and gas hydrates resources or other suitable targets of acoustic surveys.  相似文献   

梯度塑性理论及其在地质灾害预测研究中的应用     

王学滨  唐巨鹏  潘一山 《中国地质灾害与防治学报》2004,15(2):53-58,43

岩石结构稳定性问题是岩土工程实践中迫切需要解决的重要课题之一。文章以地震为例，讨论了地质灾害的局部化特征，介绍了经典弹、塑性理论的某些缺陷及梯度塑性理论的几点优越性：(1)控制方程总是适定的；(2)病态网格依赖性消失；(3)局部化带宽度由材料的内部长度完全确定；(4)可对岩石结构的尺寸效应及失稳回跳进行合理解释和预测；(5)对预测宏观及微观问题均比较有效。介绍了基于梯度塑性理论的岩石变形、破坏及稳定性研究进展。梯度塑性理论可用于研究单轴压缩条件下，岩石试件发生剪切破坏时全程应力一应变曲线、尺寸效应、剪切带倾角尺寸效应及失稳回跳等问题。它们对土木工程及岩土工程均十分重要。若将单轴压缩岩样比拟为矿柱，则该失稳判据即为矿柱岩爆准则。梯度塑性理论可用于研究韧性断层带内部应变、应变率分布规律、断层带错动位移及带内孔隙度分布规律，为韧性断层带定量分析提供了新的手段。此外，该理论还可对直剪试验机——岩样系统不稳定性进行分析，系统失稳可比拟为断层岩爆。发展基于梯度塑性理论尺度律及失稳判据等解析解一方面可加深对岩石变形、破坏的理解；另一方面。还可用来检验数值结果的正确性。  相似文献   

雷歌源头及传播原点探析     

杨励轩 《广东海洋大学学报》2014,(2):49-53

在雷州半岛民系结构变迁史与我国悠久而顽强的民歌传统等众多因素作用下,闽南民歌获得落地三雷的历史机遇,并随着雷话的生成及扩张进而本土化生成富有本土气息的雷歌,获得当地民众的文化认可,成为雷州文化重要构成之一。  相似文献   

用于声波方程数值模拟的时间-空间域有限差分系数确定新方法   总被引：4，自引：4，他引：0       下载免费PDF全文

梁文全  杨长春  王彦飞  刘红伟 《地球物理学报》2013,56(10):3497-3506

声波方程数值模拟已广泛应用于理论地震计算,同时构成了地震逆时偏移成像技术的基础.对于有限差分法而言,在满足一定的稳定性条件时,普遍存在着因网格化而形成的数值频散效应.如何有效地缓解或压制数值频散是有限差分方法研究的关键所在.为精确求解空间偏导数,相继发展了高阶差分格式优化方法和伪谱方法.近期,为更好地缓解数值频散,提出了时间-空间域有限差分方法,该方法采用了泰勒展开近似方法来确定有限差分格式系数,因而只能保证在一定的小范围内很好的拟合波场传播规律.为进一步压制数值频散效应,本文引入了时间-空间域特定波数点满足频散关系的方法,根据震源、波速和网格间距确定波数范围,同时考虑了多个传播角度,然后建立方程确定了相应的有限差分格式系数,使得差分系数能在更大范围符合波场传播规律.通过频散分析和正演模拟,验证了本文方法的有效性.  相似文献   

Movements in the harlequin fish (Othos dentex), a large predatory serranid from southern Australia: implications for detection and protection     

S Bryars  PJ Rogers 《新西兰海洋与淡水研究杂志》2016,50(4):600-618

The harlequin fish (Othos dentex) is the largest serranid found in the temperate waters of southern Australia. Acoustic telemetry was used to continuously track the movements and activity patterns of 10 harlequin fish (330–620?mm total length; 0.5–3?kg weight) for a 16-month period at a coastal reef site. Data showed that the harlequin fish is a site-attached, diurnal predator, with a relatively small home range in comparison with other temperate reef fishes from Australia and New Zealand. These characteristics indicate that the harlequin fish is susceptible to localised depletions from fishing, but that it can be protected within no-take marine protected areas and can be detected with appropriate daytime monitoring techniques. Individuals also displayed discrete depth preferences on the reef slope, evidence of a nocturnal home base, and homing ability following disturbance from an extreme storm event.  相似文献   

南黄海盆地南部坳陷南五凹三垛组剥蚀量研究     

袭著纲  王鹏 《江苏地质》2014,38(4):536-541

南黄海盆地南五凹自白垩纪以来经历了4期构造运动,其中古近纪末期三垛运动最为强烈,造成大范围的剥蚀。结合井资料,综合利用泥页岩声波时差法、镜质体反射率Ro差值法,从点上对三垛组剥蚀量进行了恢复;然后依托二维地震剖面,利用地层趋势法对该期剥蚀量进行了区域成图。结果表明,该事件中南五凹最大剥蚀厚度在凹陷西部,一般为700~950 m;东部剥蚀厚度一般为300~500 m,整体剥蚀厚度小于新近系地层补偿厚度。三垛组剥蚀量的研究对认识南五凹的成藏史及油气分布规律具有重要意义。  相似文献   

Monitoring and evaluating the stability of soil slopes: A review on various available methods and feasibility of acoustic emission technique     

《Comptes Rendus Geoscience》2014,346(9-10):223-232

Landslide is considered as one of the major natural hazards that cause enormous social and economic losses. Some techniques have been introduced to monitor the stability of slopes, such as the global positioning system (GPS), the geographic information system (GIS), aerial photography, and inclinometers. Each one of these offers advantages against others, but at the same time also possesses different limitations. Acoustic emission (AE) has recently been recognized as one of the feasible techniques to monitor soil slope. This article addresses issues involved in application of AE techniques for soil slope monitoring. If it is properly instrumented, AE could provide effective solutions for detecting early activities related to landslide development and giving early warning to such failures.  相似文献   

Variations in sediment yield over the advance and retreat of a calving glacier, Laguna San Rafael, North Patagonian Icefield     

Michèle Koppes  Richard Sylwester  Bernard Hallet 《Quaternary Research》2010,73(1):84-95

Bathymetric and sub-bottom acoustic data were collected in Laguna San Rafael, Chile, to determine sediment yields during the Little Ice Age advance and subsequent retreat of San Rafael Glacier. The sediment volumes and subaqueous landforms imaged are used to interpret the proglacial dynamics and estimate erosion rates from a temperate tidewater glacier over a complete advance-retreat cycle. Sediment yields from San Rafael Glacier averaged 2.7 × 10⁷ m³/a since the end of the Little Ice Age, circa AD 1898, corresponding to average basin-wide erosion rates of 23 ± 9 mm/a; the highest erosion rates, 68 ± 23 mm/a, occurred at the start of the retreat phase, and have since been steadily decreasing. Erosion rates were much lower during glacial advance, averaging at most 7 mm/a, than during retreat. Such large glacial sediment yields over two centuries of advance and retreat suggest that the contribution of sediments stored subglacially cannot account for much of the sediment being delivered to the terminus today. The detailed sub-bottom information of a proglacial lagoon yields important clues as to the timing of erosion, deposition and transfer of glacigenic sediments from orogens to the continental shelves, and the influence of glacier dynamics on this process.  相似文献