EH4及地质雷达在隧道事故调查中的应用

引水隧道施工中屡次发生坍塌,用探地雷达对衬砌质量及地质情况进行探测。经数据反演,清晰勾画出衬砌背后空洞、松散堆积体分布范围,地下水的赋存特征,为治理事故提供切实可靠依据。     

CHIM法在双沟金矿深部找矿中应用及效果

双沟金矿常规找矿方法难有突破。用地电化学勘查法(CHIM)对矿区深部开展隐伏矿预测,共圈定金异常4个,经钻探工程验证,深部已发现金矿脉。     

地质雷达在公路山体地质灾害调查中的应用

对临沧市南撒至班考二级公路山体地质灾害勘察中,地质雷达取得了较好的地质效果,确定地下岩溶发育区的空间展布规律、岩溶破碎带的形态及延伸,为进一步认识山体地质灾害及其勘察治理提供了地球物理依据。     

月球探测中月面热环境影响的研究现状

在月球探测中,多光谱、热红外、被动微波辐射等探测技术被广泛应用于月表物质组分和物理特性的探测,也积累了大量探测数据。月球太阳辐照、月球表面温度、地球反照和内部热流等月面热环境的变化,改变了月表物质反射率、热发射率以及其他电磁学等基本性质,制约了探测数据的准确解译;同时,大幅度的太阳辐射强度和月面温度变化也直接威胁月面探测中巡视探测器和宇航员的安全。但是,目前月球表面热环境对探测活动的影响认识还比较欠缺,月面热环境的时空变化规律认识还不够充分,在实验研究不足的情况下对各种探测方式的影响缺乏系统的理解。结合月球探测的发展,进一步立足实验手段和探测结果,通过开展不同地形条件下月面太阳辐射和物理温度的时间变化和空间分布规律研究、探测数据与月面热环境参数时空匹配问题研究、建设具备类似物质组成和月面热环境特征的实验场地以及开展系统的热环境影响模拟实验研究,全面认识月面热环境参数的时空变化规律,探讨月面热环境对不同探测方式的影响将是月面热环境研究的重要内容。     

塔里木盆地西部玛东冲断带构造特征与形成演化

玛东冲断带属典型的后展式叠瓦冲断带,前三排断裂冲断作用形成于桑塔木组沉积之前,第④和第⑤排断层形成于奥陶纪末。冲断带南部位于和田古隆起岩溶斜坡,奥陶系岩溶储层充填程度低,前三排构造在海西晚期内有活化特征,有助于缝洞型储层形成。冲断带南部中寒武统膏盐层厚度比北部小,断裂活化与中下寒武统烃源岩主生烃期配合良好,油气垂向输导能力大于北部,奥陶系风化壳油气丰度大于北部。整个冲断带由于寒武系膏盐层封盖作用,滑脱断层向上输导油气的数量有限,大部分油气仍滞留在中下寒武统中,具较大勘探潜力。     

岩性油气藏关键技术攻关与应用研究——以准噶尔盆地准东阜11井区为例

随着准噶尔盆地腹部及准东地区勘探程度不断提高,勘探对象也变得复杂,已往古凸起上的断块和低幅度背斜为主的勘探目标变得越来越少,勘探目标转向斜坡区和深凹陷的岩性油气藏成为必然趋势,此类油气藏的主要特点是:圈闭幅度较低,砂层厚度较小,横向变化快,地震识别、落实评价困难.本文针对地质难点,以准噶尔盆地准东阜11井区岩性油气藏为研究对象,逐步形成准噶尔盆地岩性油气藏勘探方法、应用效果体系;在具体工作中利用地质、地震、测井相结合的综合研究方法,分析了准东阜11井区岩性油气藏特征,建立了岩性油气藏勘探理论和方法,开发和自研出了一套适合准噶尔盆地碎屑岩岩性圈闭识别与评价的技术系列,主要包括精细的井震标定技术、精细的全三维自动追踪技术、断裂识别技术、动态构造演化分析技术、沉积微相分析技术、储层预测技术、流体预测技术及有利目标区块选择评价技术;利用此技术系列对准东地区阜11井区侏罗系三工河组(J1s)发育的岩性圈闭进行了综合预测,识别了三个可供钻探的断层-岩性圈闭,其沉积微相为扇三角洲前缘的席状砂,圈闭面积在1.75 km2～6.1 km2之间,砂岩厚度在10 m～25 m之间,油气检测处于有利位置,累计圈闭面积达12.39km2,从而扩大了该区岩性圈闭识别的数量和精度,为岩性油气藏的勘探、开发提供了有力的技术支撑.     

大地水准面异常在湖南地区的地球物理解释

以湖南地区为例,利用超高阶地球重力位模型EGM2008计算了研究区的重力大地水准面,并采用棱柱体公式和球体公式相结合的方法分别进行了完全地形改正和Airy-Heiskanen局部均衡改正,得到布格大地水准面和均衡大地水准面.对三种大地水准面进行不同波长分量的分离处理,得到包含不同深度异常信息的剩余大地水准面,并结合其他地球物理资料对研究区进行了详细的地球物理解释.结果表明,剩余重力大地水准面可以有效地反映出研究区内的深部构造特征,如深大断裂带分布、构造块体位置、上地幔密度横向分布等,但对地壳内异常结构反映不明显;研究区岩石圈密度变化相对平缓,厚度由东向西增加;根据剩余均衡大地水准面及研究区Airy局部均衡莫霍面,可以大致推测出研究区的莫霍面起伏形态以及均衡状态,可作为一种有用的参考信息.     

Why Web GIS May Not Be Enough: A Case Study with the Virtual Research Vessel

During several decades of investigation, the East Pacific Rise seafloor-spreading center at 9°-10°N has been explored by marine geologists, geophysicists, chemists, and biologists, and has emerged as one of the best studied sections of the global midocean ridge. It is an example of a region for which there is now a great wealth of observational data, results, and data-driven theoretical studies. However, these have yet to be fully utilized, either by research scientists or educators. While the situation is improving, a large amount of data, results, and related theoretical models still exist either in an inert, noninteractive form (e.g., journal publications) or as unlinked and currently incompatible computer data or algorithms. Presented here is the prototype of a computational environment and toolset, called the Virtual Research Vessel, to improve the situation by providing marine scientists and educators with simultaneous access to data, maps, and numerical models. While infrastructure is desired and needed for ready access to data and the resulting maps via web GIS in order to link disparate data sets (data to data), it is argued that data must also be linked to models for better exploration of new relations between observables, refinement of numerical simulations, and the quantitative evaluation of scientific hypotheses. For widespread data access, web GIS is therefore only a preliminary step rather than a final solution, and the ongoing implementation of the Virtual Research Vessel (scheduled for final completion in 2004-2005) is a case study for the midocean ridge community to test the effectiveness of moving beyond the data-to-data mode towards data-to-models and data-to-interpretation.     

The national geophysical data center bathymetric program

The National Geophysical Data Center's (NGDC's) mission is data management in the broadest sense, playing a role in the nation's research into the environment and providing data to a wide group of users. NGDC also operates components of the International Council of Scientific Unions (ICSU) World Data Center A. The Marine Geology and Geophysics Division of NGDC handles bathymetric data acquisition, manipulation, archival, and dissemination and operates the International Hydrographic Organization Data Center for Digital Bathymetry. Four major data bases have been developed to manage the large volume of data received: the Global Marine Geophysical Data Base (geophysical data acquired in a time series); the NOAA National Ocean Service Hydrographic Data Base; the International Hydrographic Data Base (contains bathymetric data, other than NOS surveys, with no time‐tagging); and the Multibeam Bathymetric Data Base. In addition, gridded data sets such as ETOPO5 are available from NGDC. Bathymetric data are acquired by NGDC through data exchange, funded and contract programs, processing of long‐term data holdings, data digitization from hardcopy sources, and national and international linkages. NGDC personnel participate nationally and internationally on numerous committees associated with studies of the seafloor including charting and bathymetric needs.     

Development of tongue-shaped and multilobate rock glaciers in alpine environments – Interpretations from ground penetrating radar surveys

Rock glaciers occur as lobate or tongue-shaped landforms composed of mixtures of poorly sorted, angular to blocky rock debris and ice. These landforms serve as primary sinks for ice and water storage in mountainous areas and represent transitional forms in the debris transport system, accounting for ~ 60% of all mass transport in some alpine regions. Observations of active (flowing) alpine rock glaciers indicate a common association between the debris that originates from cirque headwalls and the depositional lobes that comprise them. The delivery of this debris to the rock glacier is regulated primarily by the rate of headwall erosion and the point of origin of debris along the headwall. These factors control the relative movement of individual depositional lobes as well as the overall rate of propagation of a rock glacier. In recent geophysical studies, a number of alpine rock glaciers on Prins Karls Forland and Nordenskiöldland, Svalbard, Norway, and the San Juan Mountains of southwest Colorado, USA, have been imaged using ground penetrating radar (GPR) to determine if a relationship exists between the internal structure and surface morphology. Results indicate that the overall morphologic expression of alpine rock glaciers is related to lobate deposition during catastrophic episodes of rockfall that originated from associated cirque headwalls. Longitudinal GPR profiles from alpine rock glaciers examined in this study suggests that the difference in gross morphology between the lobate and tongue-shaped rock glaciers can be attributed primarily (but not exclusively) to cirque geometry, frequency and locations of debris discharge within the cirque, and the trend and magnitude of valley gradient in relation to cirque orientation. Collectively, these factors determine the manner in which high magnitude debris discharges, which seem to be the primary mechanism of formation, accumulate to form these rock glaciers.