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1.
葛店煤矿双庙扩大区位于豫、皖两省交界处。勘探区为一轴向北北东向的不对称向斜构造,地层倾角26°~30°,测区深部有岩浆岩侵入体,严重影响煤层赋存形态;地表条件复杂,村庄密集、河流较多,测区东侧塌陷区水塘大面积分布.三维地震勘探野外施工难度大。本区地震勘探观测系统设计为12线18炮制,为避免偏移归位及叠加次数降低等问题,在向斜轴部两侧、村子周边及河岸处适当加密炮点,并在塌陷区利用钢钎插置检波器以保证CDP点完整性。数据处理采取了叠前反褶积、叠前时间偏移等技术,数据处理效果显著。遵循多波组对比、多个数据体综合解释的原则,以纵向、横向和任意时间剖面相结合,充分利用三维可视化技术进行地震资料解释。本次勘探成果查明了主采煤层三2^2、二2煤层的构造形态及埋藏深度;解释落差5m以上断层34条,其中修改原有断层5条;另外新发现小于5m的异常断点22个。经巷道验证煤层底板标高误差0.43%~1.96%,巷道已揭露断层7条,与解释成果基本一致。  相似文献   
2.
贾汪煤田的基本构造形态为贾汪向斜。通过对贾汪向斜北东延长段原地系统和外来系统的分析研究,认为在贾汪石炭——二叠纪煤田北界伏山前断裂的北东盘上,受构造应力的影响,奥陶系沿着其与寒武系界面间的软弱层被推覆,在原地代之以大面积分布的是青白口——震旦系及部分寒武系而非石炭——二叠系,从而造成了贾汪煤田没有向北东继续延伸。  相似文献   
3.
Seismic and sequence stratigraphy analyses, petroleum-well control and surface data studies of the Majoura–El Hfay region in the Central Atlas of Tunisia had led to identify and calibrate Jurassic seismic horizons. Seismic stratigraphic sections, seismic tectonics analyses, isochron and isopach mapping of Jurassic sequences show a differentiated structuring of platform and depocentre blocks limited by deep-seated NE–SW, north–south east–west and NW–SE faults intruded by Upper Triassic salt. The early salt migration seems to have started by the platform fracturing during the Lower Liassic rifting event. These movements are fossilized by thickness variations of Jurassic horizons, aggrading and retrograding onlap and toplap structures between subsiding rim-syncline gutters and high platform flanks intruded by salt pillows and domes. The salt migration is also attested by Middle and Upper Jurassic space depocentre migrations. Around the Majoura–El Hfay study blocks bounded by master faults, Triassic salt have pierced the Cretaceous and Tertiary sedimentary cover in a salt diapir extrusion and salt wall structures. To cite this article: D. Tanfous Amri et al., C. R. Geoscience 337 (2005).  相似文献   
4.
地质图切剖面中褶皱构造的计算机辅助编绘   总被引:7,自引:2,他引:7  
计算机对褶皱的处理能力的强弱,是决定地质图切剖面计算机辅助编绘系统实用价值大小的一个重要指标。以兰姆赛分类方案为基础,通过褶皱形态的几何特征分析,提出一种针对简单背,向斜构造的计算机辅助设计算法,并编写出相应的褶皱剖面形态的模拟程序,利用各种不同形态的褶皱实例进行试验。证明该种算法正确可靠,将其嵌入作先前开发的地质图切剖面编绘程序中,可大大提高地质图切剖面编绘的自动化水平。  相似文献   
5.
圆梁山隧道毛坝向斜段典型岩溶现象及发育分布特征   总被引:11,自引:0,他引:11  
圆梁山隧道毛坝向斜段核部及两翼的可溶地层中发衣分布有大量的典型岩溶现象,本文详尽讨论了岩溶洼地,槽谷,巨型组合槽谷和地下溶洞等大型岩溶形态的基本特征,形成机制,受控因素,并进一步认识到其发育分布主要受控于岩性和构造因素。  相似文献   
6.
冀北承德盆地中生代侏罗纪地层序列较齐全,但作为关键层位之一的九龙山组一直缺乏高精度年代学的约束。笔者首次对九龙山组凝灰岩夹层进行了LA-ICP-MS锆石U-Pb高精度定年,获得凝灰岩中岩浆锆石206Pb/238U加权平均年龄164.1±1.3 Ma。综合研究及对比表明,九龙山组的时限为158~164Ma,属中侏罗世晚期至晚侏罗世早期,对应于国际地层表的牛津期至卡洛维期,其沉积时间相对短暂。在此基础上,更新了研究区侏罗系年代地层柱状图,该认识对于深入研究燕山地区中生代侏罗纪地层格架及构造岩浆演化过程具有重要意义。  相似文献   
7.
留村金矿位于山东莱州市城区西南12 km的留村断裂带上,是发育于古老变质岩中的小型石英脉型金矿。为深入研究该矿区地层、构造与矿体在地下的延伸分布情况,加快后续数字化矿山建设,山东黄金集团应用Vulcan矿业软件对矿区开展三维地质建模。在收集相关地质实物资料的基础上,通过建立地质数据库、数据转换、地质解译等系列功能操作建立了矿区地表、岩体、构造及矿体模型,并对其进行任意剖割划分,实现了矿区地层岩性、地质构造、矿体的三维可视化,促进了本区矿体赋存规律的研究以及三维空间的成矿预测。同时利用软件强大的数据处理功能对资源量进行估值,本次估值的金资源量为1984.18 kg,与原详查报告中提交的金资源量2009.34 kg误差仅为1.25%。经估值后的每个矿块段都被赋予了精确的资源量数据,为后续矿山采矿设计与排产计划提供了准确的数据支撑,助力实现数字化、智能化矿山建设。  相似文献   
8.
The Aït Attab syncline, located in the Central High Atlas, displays a curved geometry in plan view, and is considered as one of the most spectacular fold shapes in the Central High Atlasic belt. We conducted a paleomagnetic study in Jurassic-Cretaceous red beds to investigate the origin of this geometry. The Natural Remanent Magnetization (NRM) is dominated by a secondary magnetization carried by haematite with unvarying normal polarity that has been dated at about 100 Ma. The regional fold test performed in both limbs of the syncline is positive and the paleomagnetic vectors (after tectonic correction) are parallel throughout the curvature, indicating a negative oroclinal bending test. These results are inconsistent with previous works that consider the bent geometry of this syncline to result from subsequent distortion of originally NE–SW trending structures by rotation about a vertical axis. We interpret the NRM data to demonstrate that the changing trend of the Aït Attab syncline is a primary feature, resulting from the influence of pre-existing, NE–SW and E-W-striking extensional faults that developed during a strike-slip regime. Paleomagnetic results also reveal that the tilting observed in the sampled red beds is post Albian, probably linked to the Cenozoic inversion of the High Atlasic belt.  相似文献   
9.
本文对承德县甲山正长岩体进行了岩石谱系单位划分,归并为甲山序列;对岩体的岩石化学、微量元素、稀土元素进行分析,提出深成岩体就位机制为热轻气球膨胀型式的模式。  相似文献   
10.
Fan‐shaped polycrystalline staurolite porphyroblasts, 3–4 cm in length and 0.5 cm in width, occur together with centimetre‐sized euhedral prismatic staurolite porphyroblasts in pelitic schists of the Littleton Formation on the western overturned limb of the Bolton syncline in eastern Connecticut. The fans consist of intergrown planar splays of [001] elongated prisms, which are crudely radial from a single apex. The apical angles of the radial groupings range up to 70°. The orientations of the individual staurolite prisms are related by a rigid rotation about an axis perpendicular to the fan plane. The zone axes [001] always lie in the plane of the fan. Although the angle between the [100] zone axes of the individual prisms is uniform in each fan, it ranges from +30° to ?30° in different fans. Internally, the fans display: (i) remnants of a passively captured Si foliation defined by disc‐shaped quartz blebs (type 1 inclusions) and layers of very fine carbonaceous material and tabular ilmenite platelets; (ii) bent staurolite blades and undulose extinction along low‐angle (010) subgrain boundaries near the apex of the fans; (iii) wedge‐shaped dilatational zones containing equigranular inclusion‐free quartz, mica and staurolite, and (iv) growth‐related quartz inclusion trails roughly perpendicular to a crystal face (type 2 inclusions). The Si inclusion trails are typically perpendicular to the fan surface, radiate parallel to the blades, and show little to no curvature except at the very edge of the fans where they abruptly curve through nearly 90° into parallelism with an external Se foliation. Careful examination of the three‐dimensional geometry of fans based on U‐stage measurements, serial sections and two‐circle optical goniometric measurements permits a detailed reconstruction of their sequential development. The origin of a fan involves limited intracrystalline deformation and brittle crack dilation, spalling, rotation, and growth of small marginal fragments and of new staurolite along wedge‐shaped zones along the Si inclusion surfaces. Fans preferentially develop in porphyroblasts in which Si is subparallel to the 010 cleavage. These internal features reflect the rotation and deformation of a brittle porphyroblast relative to syn‐growth shear stresses.  相似文献   
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