Three-dimensional structural models,evolution and petroleum geological significances of transtensional faults in the Ziyang area,central Sichuan Basin,SW China

With drilling and seismic data of Transtensional(strike-slip)Fault System in the Ziyang area of the central Sichuan Basin,SW China plane-section integrated structural interpretation,3-D fault framework model building,fault throw analyzing,and balanced profile restoration,it is pointed out that the transtensional fault system in the Ziyang 3-D seismic survey consists of the northeast-trending F_(I)19 and F_(I)20 fault zones dominated by extensional deformation,as well as 3 sets of northwest-trending en echelon normal faults experienced dextral shear deformation.Among them,the F_(I)19 and F_(I)20 fault zones cut through the Neoproterozoic to Lower Triassic Jialingjiang Formation,presenting a 3-D structure of an“S”-shaped ribbon.And before Permian and during the Early Triassic,the F_(I)19 and F_(I)20 fault zones underwent at least two periods of structural superimposition.Besides,the 3 sets of northwest-trending en echelon normal faults are composed of small normal faults arranged in pairs,with opposite dip directions and partially left-stepped arrangement.And before Permian,they had formed almost,restricting the eastward growth and propagation of the F_(I)19 fault zone.The F_(I)19 and F_(I)20 fault zones communicate multiple sets of source rocks and reservoirs from deep to shallow,and the timing of fault activity matches well with oil and gas generation peaks.If there were favorable Cambrian-Triassic sedimentary facies and reservoirs developing on the local anticlinal belts of both sides of the F_(I)19 and F_(I)20 fault zones,the major reservoirs in this area are expected to achieve breakthroughs in oil and gas exploration.

Three-dimensional geological modelling and direction of hydrothermal alteration of Horne deposit, Blake River Group, Quebec, Canada

The Horne deposit with rich Cu and Au in Noranda region of Black River Group in Quebec has high economic significance.Current researches on Horne deposit are mostly based on two-dimensional maps and statistical data.It is hard to reflect the spatial structure and characteristics of Horne orebody directly.In this paper,GIS was used to digitize the mining plan-view maps at different depths,stope maps,the boundary of the massive sulfide in drilling trajectories as well as the grade data of Au and Cu of Horne deposit.Meanwhile,the authors established the grade attribute database.Subsequently the three-dimensional(3D)geological model and grade attribute model of Horne orebody were established by Geological Object Computer Aided Design(GOCAD).Positions of two vents and directions of hydrothermal alteration in Horne deposit were inferred based on the property of the major fault,characteristics of hydrothermal alteration,the enrichment morphology and spatial distribution of high-grade Cu in the Cu attribute model.

Application of oblique photogrammetry technique in geological hazard identification and decision management

With the continuous development of the oblique photography technique, it has been used more and more widely in the field of geological disasters. It can quickly obtain the three-dimensional(3D) real scene model of dangerous mountainous areas under the premise of ensuring the safety of personnel while restoring the real geographic information as much as possible. However, geological disaster areas are often accompanied by many adverse factors such as cliffs and dense vegetation. Based on this, the paper introduced the flight line design of oblique photogrammetry, analyzed the multi-platform data fusion processing, studied the multi-period data dynamic evaluation technology and proposed the application methods of data acquisition, early warning, disaster assessment and decision management suitable for geological disaster identification through the analysis of actual cases, which will help geologists to plan and control geological work more scientifically and rationally, improve work efficiency and reduce the potential personnel safety hazards in the process of geological survey, to offer technical support to the application of oblique photogrammetry in geological disaster identification and decision making and provide the scientific basis for personal and property safety protection and later-stage geological disaster management in disaster areas.

Risk Assessment of Coal Mine Water Hazard Based on Three-Dimensional Model of Geology and Underground Space

Mine safety have top-five disasters,which including the water,gas,fire,dust and geological dynamic disaster.The coal mine water disaster is one of the important factors which restricted the development of China’s coal production.It is showed by statistics that 60%of mine accidents are affected by groundwater,which not only result in the production losses,casualties and a variety of

3D geological modeling for mineral resource assessment of the Tongshan Cu deposit,Heilongjiang Province,China

Three-dimensional geological modeling （3DGM） assists geologists to quantitatively study in three-dimensional （3D） space structures that define temporal and spatial relationships between geological objects. The 3D property model can also be used to infer or deduce causes of geological objects. 3DGM technology provides technical support for extraction of diverse geoscience information, 3D modeling, and quantitative calculation of mineral resources. Based on metallogenic concepts and an ore deposit model, 3DGM technology is applied to analyze geological characteristics of the Tongshan Cu deposit in order to define a metallogenic model and develop a virtual borehole technology; a BP neural network and a 3D interpolation technique were combined to integrate multiple geoscience information in a 3D environment. The results indicate： （1） on basis of the concept of magmatic-hydrothermal Cu polymetallic mineraliza- tion and a porphyry Cu deposit model, a spatial relational database of multiple geoscience information for mineralization in the study area （geology, geophysics, geochemistry, borehole, and cross-section data） was established, and 3D metallogenic geological objects including mineralization stratum, granodiorite, alteration rock, and magnetic anomaly were constructed; （2） on basis of the 3D ore deposit model, 23,800 effective surveys from 94 boreholes and 21 sections were applied to establish 3D orebody models with a kriging interpolation method; （3） combined 23,800 surveys involving 21 sections, using VC＋＋ and OpenGL platform, virtual borehole and virtual section with BP network, and an improved inverse distance interpolation （IDW） method were used to predict and delineate mineralization potential targets （Cu-grade of cell not less than 0.1%）; （4） comparison of 3D ore bodies, metallogenic geological objects of mineralization, and potential targets of mineralization models in the study area, delineated the 3D spatial and temporal relationship and causal processes among the ore bodies, alteration rock, metallo- genic stratum, intrusive rock, and the Tongshan Fault. This study provides important technical support and a scientific basis for assessment of the Tongshan Cu deposit and surrounding exploration and mineral resources.

Implicit modeling of complex orebody with constraints of geological rules

To dynamically update the shape of orebody according to the knowledge of a structural geologist’s insight,an approach of orebody implicit modeling from raw drillhole data using the generalized radial basis function interpolant was presented.A variety of constraint rules,including geology trend line,geology constraint line,geology trend surface,geology constraint surface and anisotropy,which can be converted into interpolation constraints,were developed to dynamically control the geology trends.Combined with the interactive tools of constraint rules,this method can avoid the shortcomings of the explicit modeling method based on the contour stitching,such as poor model quality,and is difficult to update dynamically,and simplify the modeling process of orebody.The results of numerical experiments show that the 3D ore body model can be reconstructed quickly,accurately and dynamically by the implicit modeling method.

A method of reconstructing 3D model from 2D geological cross-section based on self-adaptive spatial sampling:A case study of Cretaceous McMurray reservoirs in a block of Canada

An orthogonal 2D training image is constructed from the geological analysis results of well logs and sedimentary facies;the 2 D probabilities in three directions are obtained through linear pooling method and then aggregated by the logarithmic linear pooling to determine the 3 D multi-point pattern probabilities at the unknown points,to realize the reconstruction of a 3 D model from 2D cross-section.To solve the problems of reducing pattern variability in the 2 D training image and increasing sampling uncertainty,an adaptive spatial sampling method is introduced,and an iterative simulation strategy is adopted,in which sample points from the region with higher reliability of the previous simulation results are extracted to be additional condition points in the following simulation to improve the pattern probability sampling stability.The comparison of lateral accretion layer conceptual models shows that the reconstructing algorithm using self-adaptive spatial sampling can improve the accuracy of pattern sampling and rationality of spatial structure characteristics,and accurately reflect the morphology and distribution pattern of the lateral accretion layer.Application of the method in reconstructing the meandering river reservoir of the Cretaceous McMurray Formation in Canada shows that the new method can accurately reproduce the shape,spatial distribution pattern and development features of complex lateral accretion layers in the meandering river reservoir under tide effect.The test by sparse wells shows that the simulation accuracy is above 85%,and the coincidence rate of interpretation and prediction results of newly drilled horizontal wells is up to 80%.

Enhanced history matching process by incorporation of saturation logs as model selection criteria

This paper proposes a methodology for an alternative history matching process enhanced by the incorporation of a simplified binary interpretation of reservoir saturation logs(RST) as objective function. Incorporating fluids saturation logs during the history matching phase unlocks the possibility to adjust or select models that better represent the near wellbore waterfront movement, which is particularly important for uncertainty mitigation during future well interference assessments in water driven reservoirs. For the purposes of this study, a semi-synthetic open-source reservoir model was used as base case to evaluate the proposed methodology. The reservoir model represents a water driven, highly heterogenous sandstone reservoir from Namorado field in Brazil. To effectively compare the proposed methodology against the conventional methods, a commercial reservoir simulator was used in combination with a state-of-the-art benchmarking workflow based on the Big LoopTMapproach. A well-known group of binary metrics were evaluated to be used as the objective function, and the Matthew correlation coefficient(MCC) has been proved to offer the best results when using binary data from water saturation logs. History matching results obtained with the proposed methodology allowed the selection of a more reliable group of reservoir models,especially for cases with high heterogeneity. The methodology also offers additional information and understanding of sweep behaviour behind the well casing at specific production zones, thus revealing full model potential to define new wells and reservoir development opportunities.

煤矿待采孤立块段地质构造复杂程度评价

煤矿区地质构造复杂程度是煤矿安全生产时最为关心的问题之一。结合已采区探采对比结果和前期生产的经验,对比待采块段与已采采区地质构造复杂程度,可以用于指导待采块段后期的补勘设计、采掘设计、采煤方法选择,以及煤矿水害防治和瓦斯治理等。为构建煤矿区地质构造复杂程度的定量评价模型,采用“滑动窗口法”统计各评价单元指标数据,采用AHP-熵权主客观确权法确定指标权重,继而栅格加权叠加计算,完成地质构造复杂程度综合指数图,对煤矿区地质构造复杂程度进行了等级划分与评价。在上述研究基础上,对比已采区和西一采区—东一采区间待采孤立块段范围地质构造复杂程度评价结果,得出待采块段以极复杂型构造为主。最终评价结果表明,评价指标、评价方法和评价模型总体是合理的。

基于加权信息量模型的地质灾害易发性评价

湘乡市地质灾害频发,对该地区造成了巨大的经济损失和人员伤亡,基于研究区DEM、遥感等数据,利用了ArcGIS软件对湘乡市划分为10 m×10 m的栅格单元,选取了高程、坡度、坡向、工程地质岩组、月平均降雨量等8个指标作为评价因子,通过主客观权重相结合的方法确定了各指标的权重,结合信息量模型计算出研究区各评价单元的信息量值,采用自然断点法将研究区划分为高易发区、中易发区、低易发区,AUC值为0.863,与历史发灾情况吻合,表明了该方法具有较好的评价效果,为后续的防灾减灾提供了理论依据。

精细化贴近摄影测量技术在地质灾害调查中的应用

地质灾害工作区域条件复杂,多为陡峭险峰地带,易落石滑坡,为地质灾害调查工作带来诸多不便,增加了传统地质灾害调查工作的危险系数。随着无人机摄影测量技术的研究及发展,其以高效率、低成本、安全性高、成果多样化等优势在地质灾害调查中得到应用。本文阐述以一种新型的精细化建模方式——贴近摄影测量技术应用在地质灾害调查中,通过该技术制作某滑坡灾害区精细化实景三维模型,解译山体细部纹理,监测危岩体发育情况。经项目实验,精细化贴近摄影测量技术满足了地质灾害调查技术的要求,实现了由“实地调查”到“解译调查”的过渡。

A methodology for 3D modeling and visualization of geological objects

Geological body structure is the product of the geological evolution in the time dimension, which is presented in 3D configuration in the natural world. However, many geologists still record and process their geological data using the 2D or 1D pattern, which results in the loss of a large quantity of spatial data. One of the reasons is that the current methods have limitations on how to express underground geological objects. To analyze and interpret geological models, we present a layer data model to organize different kinds of geological datasets. The data model implemented the unification expression and storage of geological data and geometric models. In addition, it is a method for visualizing large-scaled geological datasets through building multi-resolution geological models rapidly, which can meet the demand of the operation, analysis, and interpretation of 3D geological objects. It proves that our methodology is competent for 3D modeling and self-adaptive visualization of large geological objects and it is a good way to solve the problem of integration and share of geological spatial data.

From the Area to the Point-Study on the Key Technology of 3D Geological Hazard Modeling in Three Gorges Reservoir Area

Taking hundreds of pieces of hazardous geological maps （1 ： 10 000） of Three Gorges res-ervoir area （3GR） as background, we establish regional three-dimensional （3D） geo-hazard modelusing DEM （digital elevation model） superposed surface images and geo-hazards elements. Based on landslides and other geo-hazard survey data,using improved B-REP（boundary representa-tion）entity data structure （two-body 3D data structure）, we set up 3D solid models for each hazardous bodies in each hazardous geological maps. Then we integrate the two types of 3D models with different scales from area to point, which are the regional geo-hazard 3D model and the solid models of each disaster body, in order to provide a visual processing and analysis plat-form for danger partition, stability evaluation, disaster prevention and control, early warning and command.

以饱和度测井数据为油藏模型选择标准的改进历史拟合方法

提出了一种将储集层饱和度测井数据二元简化形式作为油藏模型选择标准的改进历史拟合方法,使用半合成开源油藏模型作为基础模型对提出的方法进行评估,并与常规方法进行了比较。历史拟合阶段引入流体饱和度测井数据,有助于调整或选择能够更好地表征近井地带水驱前缘推进的模型,从而有效降低水驱油藏后续井间干扰评价的不确定性。研究表明,对含水饱和度测井数据进行二元分类时,马修斯相关系数作为分类指标的效果最佳。与常规方法相比,根据提出的方法可以选出一组更可靠的储集层(特别是强非均质性储集层)模型,选出的模型历史拟合效果更好,对近井地带含水饱和度、生产井及其不同层位含水率的拟合质量更好。

数字区域地质调查基本理论与技术方法研究

文章根据美国、加拿大、澳大利亚、英国等在数字填图技术方面的研究现状,结合我国实际情况,对数字填图技术的理论基础、数字填图的区调数据模型、数字填图的技术流程、实现数字填图技术的工具与方法等数字填图基本理论与技术方法进行了初步探讨。

安哥拉深水水道地质知识库建立及应用

利用浅层(上新统)三维高频地震资料的剖面、切片和属性信息,对安哥拉陆坡区深水水道特征和定量关系进行研究,在复合水道和单一水道两个层次上建立了安哥拉地区浊积水道定量化地质知识库。研究结果表明:研究区单一水道活动方式类似于曲流河点坝模式,即单一水道仅沿侧向(垂直于古流向)整体迁移,不存在整体"下游扫动"分量,且在平面上其侧积复合体呈"同心半环状",单一水道的砂体以垂向加积方式充填在轴部,厚度向边部减薄;单一水道的宽度与深度、弯曲弧长与弯曲度之间存在较好的正相关性;复合水道样式按照内部单一水道的活动方式分为(I)侧向迁移、(II)斜列迁移和(III)摆动迁移三类模式,且(I)类主要发育在高弯曲段(弯曲度>1.3),II类和III类主要发育在低弯曲段(1<弯曲度≤1.3);该地质知识库成功应用到实际三维地质建模中,具有推广价值。本文研究不仅可以完善深水水道定量分布模式,而且可以有效降低此类油田开发风险,具有理论和实际意义。

煤矿地测信息系统(MSGIS)

本文介绍了一个专门为地测部门设计和开发的软件系统——地质、测量信息系统(MSGIS),并从理论的角度着重介绍了其中的专业CAD系统(MgCAD)的系统结构、3D地质模型、图形数据库和地测图形的自动处理技术。

面向对象的地质图数据模型研究与实践

地质数据模型是地质应用问题向计算机应用系统转换的桥梁,是地质数据库建设和地质信息系统开发的基础。开发面向对象的地质图数据模型是为了更好地满足各种应用需求,合理高效地组织、存储和管理地质图数据,方便用户进行数据分析与知识发掘。基于现有的GIS空间数据建模技术和技术平台原则,结合数据库建设实践,建立了应用模型与组织模型统一的地质图数据模型。

主TIN模式下面向拓扑的三维地质块体构建方法

当前普遍采用主TIN模式对层状地质体进行三维结构建模,然而在地质块体的构建方面还有所欠缺。考虑到由于尖灭、出露等现象引起的各地质块体间空间位置关系的复杂性,根据主TIN建模的特点,处理完地层相交与高程调整之后,通过对地层面中某个区域内的三角网与上下地层中对应区域内的三角网的重叠次数的不同,设置子面类型标记,从而分离出一个地层面中不同类型的子面。依据子面的类型可以快速建立地质块体与被引用的各子面之间的对应关系,最终自动分离出地层中的各个地质块体,并保证相邻块体在邻接处有唯一的公共子面,由此可建立各地质块体间的空间拓扑关系。

一种含断层的复杂层状地质体三维自动构模方法研究

为了使复杂地质体建模过程趋向于自动化、简单化,在分析了复杂层状地质体的空间信息特征的基础上,提出了一种针对含断层的层状地质体的自动构建方法。该方法先对地质钻孔资料、地质报告图进行预处理,从而获得离散的数据点;然后选择基于表面模型的建模方法,根据从钻孔分层信息到剖面图再到地层面的建模流程,分别构建出地质体的顶、底两个地层表面模型;根据空间拓扑关系处理断层结构,将断层以两条首尾相连的约束线嵌入地面模型中;最后使用轮廓线拼接法生成侧面,将顶、底、侧面缝合成封闭的三维地层体模型。利用自主开发的三维可视化系统对该方法进行验证实现,并成功应用于山西省某煤田矿区的三维地质建模中,实践表明,该建模方法高效快速,自动化程度高,所构建的地质体模型表达复杂地质结构的效果良好。