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111.
车镇凹陷上古生界高分辨率层序地层研究 总被引:2,自引:0,他引:2
以高分辨率层序地层学原理为指导,利用测井、岩芯和录井等资料,对车镇凹陷上古生界不同级次基准面旋回进行了高分辨率层序划分。将上古生界划分为2个超长期、7个长期、16个中期和45个短期基准面旋回,精细对比研究了短期、中期和长期基准面旋回。其中,短期基准面旋回可分为2大类3种亚类,并区别出A型、B型不对称短期基准面旋回和C型对称性短期基准面旋回,总结了它们的结构特征、形成条件、岩性岩相组成;通过研究不同沉积体系下中期、长期基准面旋回特点,得出中期、长期基准面旋回的特点和发育特征,区别出不同沉积环境下层序界面特点;分析了研究区内超长期基准面旋回特征,综合分析认为车镇凹陷超长期基准面旋回以下降半旋回为主。 相似文献
112.
鱼卡煤田大煤沟组高分辨率层序地层特征及聚煤规律 总被引:1,自引:0,他引:1
利用高分辨率层序地层学理论和技术方法,综合地震、测井、岩芯和煤质资料对柴达木盆地北缘鱼卡煤田中下侏罗统大煤沟组地层河湖三角洲沉积体系进行高分辨率层序地层学分析,从中识别出短期、中期、长期3个级别的基准面旋回层序,划分出向上"变深"非对称型、向上"变浅"非对称型及对称型3种短期基准面旋回基本结构类型。依据等时地层对比法则进行不同级次基准面旋回层序的联井对比,建立了大煤沟组的等时地层格架,在等时地层格架内进行了煤层对比,并在等时地层格架内分析了聚煤规律。 相似文献
113.
Ramesh Sivanpillai X. Ben Wu R. Srinivasan Charles T. Smith Michael G. Messina 《GeoJournal》2008,71(4):211-220
Comparing satellite data derived map products are affected by differences in data characteristics, image acquisition dates,
processing techniques, and classification schemes used for assigning pixels to a thematic class. By comparing two forest maps
generated from Landsat Enhanced Thematic Mapper Plus (ETM+) and Advanced Very High Resolution Radiometer (AVHRR) images acquired
on the same day, and processed using identical classification scheme and methods these differences were minimized. The ETM+
derived map had higher classification accuracy values and more precise area estimates than the AVHRR derived map. In the ETM+
derived map, 87 of the 599 verification data were misclassified, whereas in the AVHRR derived map, 155 of the 469 verification
data were misclassified. Detailed error analyses by land cover class revealed that a land use based definition of forest accounted
for 74% (64 out of 87) and 57% (89 out of 155) of the classification errors in ETM+ and AVHRR derived maps, respectively. 相似文献
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115.
As an important reservoir type in the Bohai Bay Basin, China, lacustrine beach and bar sands which refer to the shallow water complex deposited mainly by nearshore, delta‐rim and buried hill‐related beaches as well as longshore bars were developed in a particular stage in the evolution of those faulted Cenozoic continental depressions. In the Chezhen Depression, for example, the Second Member of the Oligocene Shehejie Formation (abbr. as Es2 hereafter) formed during the rifting‐to‐thermal subsidence transitional stage. Although well developed in Es2, beach and bar sands are difficult to recognize owing to their relative thinness. The paper summarizes sedimentary characteristics of lacustrine beach and bar sands on cores and logs. Low‐angle cross‐stratification, swash stratification, as well as occasional small‐scale hummocky cross‐stratification resulted from storms can be observed in beach and bar sands. The paper distinguishes bars and beaches from each other in Es2 mainly based on the grain‐size, bed thickness, facies succession and log responses. In order to predict the distribution of beach and bars, a chrono‐stratigraphic correlation framework of Es2 in the study strata is established using a high‐resolution sequence stratigraphic approach. Es2 strata are sub‐divided into six medium‐scale cycles and the mapping of the high‐frequency cycles allows the geographic and stratigraphic distribution of both beach and bar sands to be predicted. The study shows that beach and bars are better developed in times of base‐level fall than in base‐level rise. Factors such as lake‐level fluctuation, sediment supply, palaeogeomorphology and palaeowind direction have exerted control on the formation and distribution of beach and bar sands. Finally, the genetic pattern of beach and bar sands in the Es2 unit has been constructed, which provides a foundation for the prediction of beach and bars reservoir in continental basins in general. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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117.
S. Amir Reza Beyabanaki Roozbeh Geraili Mikola Kianoosh Hatami 《Computers and Geotechnics》2008,35(3):346-356
This paper presents a new contact calculating algorithm for contacts between two polyhedra with planar boundaries in the three-dimensional discontinuous deformation analysis (3-D DDA). In this algorithm, all six type contacts in 3-D (vertex-to-face, vertex-to-edge, vertex-to-vertex, face-to-face, edge-to-edge, and edge-to-face) are simply transformed into the form of point-to-face contacts. The presented algorithm is a simple and efficient method and it can be easily coded into a computer program. In this paper, formulations of normal contact, shear contact and frictional force submatrices based on the new method are derived and the algorithm has been programmed in VC++. Examples are provided to demonstrate the new contact rule between two blocks. 相似文献
118.
砂体上倾尖灭油气藏是岩性油气藏中重要类型之一,砂体上倾尖灭的刻画与描述是上倾尖灭圈闭有效性评价的关键。在以三角洲前缘沉积为主构成的三级层序内,三角洲沉积相关砂体上倾尖灭的地质-地球物理“逐级预测”描述方法对于认识上倾尖灭油气藏分布规律及其油气勘探具有重要意义。该方法由5个部分组成:在三级层序识别的基础上,运用高精度层序地层划分技术建立了四级层序构成的高频层序地层格架;在高频层序约束下,利用地震沉积学技术描述沉积相的平面分布;在地质模型指导下,利用频谱成像技术定性确定尖灭带的分布;利用相控储层反演半定量、定量预测砂体尖灭线;根据不同成因砂体的沉积特点,利用正演模拟技术开展尖灭线的外推预测。 相似文献
119.
120.
在厚覆盖区,目前的勘查技术在探测深度和精度方面已不能满足深部资源勘查的需求,地震方法可用来弥补目前勘查技术在寻找深部隐伏矿方面的某些不足。由于金属矿区的地质构造十分复杂,金属矿勘查中的地震方法技术是一个十分复杂的课题。这里结合在甘肃金昌铜镍多金属矿区的试验研究,讨论了地震方法技术在厚覆盖区探测隐伏超基性岩体和控矿构造的试验应用效果。 相似文献