排序方式： 共有58条查询结果，搜索用时 15 毫秒
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14C加速器质谱(14C-AMS)测年技术具有测量精度高、速度快以及样品需求量少的特点,为考古年代学研究提供了一种新的途径.通过对中国考古学中的一些断代难题,例如夏商周断代工程、城头山遗址的环境考古、江西瑞昌铜岭冶铜遗址的14C-AMS测年分析,以及周原黄土地层学与年代学相结合的研究,总结了14C-AMS测年技术在提供可靠的年代、解决考古年代学中微量样品的测年难题方面,具有不可替代的优势.指出考古学的研究既要与地层学相结合,更重要的是与现代高灵敏度的测年技术相结合,并认为14C-AMS测年将成为未来中国考古年代学研究的一个重要方向. 相似文献
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为了提高煤田开采的效率,准确、快速地确定断层和裂隙发育带已迫在眉睫。而三维方差体技术突出了地层横向变化对地震道的影响,能够对三维地震地质信息进行提取,还可用于识别断层、裂隙及地层的不连续变化。这里介绍了三维方差体技术的原理及基本算法,并在山东某采区三维地震资料的解释工作中进行了实际应用。结果表明,方差体技术对断层、裂隙发育带等地质异常体具有良好的识别效果。 相似文献
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地震沉积学是在地震地层学和层序地层学基础上发展起来的、沉积地质学与地球物理学相互交叉的新兴学科,在刻画薄层砂体、表征储集层和预测岩性圈闭等方面发挥了重要作用。在表述地震沉积学发展简史的基础上,介绍了地震沉积学的基本概念、基本原理和主要研究流程;在建立精细层序地层格架基础上,重点阐述了90°相移、分频处理与频谱分解、属性优选、地层切片、地球物理反演、地震岩性解释和RGB(红色、绿色、蓝色)地震属性融合等地震沉积学关键技术以及地震沉积相实例分析。认为中国地震沉积学应该围绕不同类型沉积盆地开展油气勘探阶段地震地貌学(地震沉积相模式)和复杂(多样)地震岩性学综合研究,在油气开发阶段,充分利用RGB地震属性融合等多种地球物理方法技术,开展多种成因类型砂体构型和储集层定量表征研究。综合研究表明,地震沉积学是沉积地质学发展的新航程。 相似文献
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Simon A. J. Pattison 《Sedimentology》2020,67(1):390-430
Strongly progradational regressive stacks of shallow marine sandstones are ubiquitous in modern and ancient coastal depositional systems. Many ancient examples form prolific hydrocarbon and freshwater reservoirs in the subsurface. One of the best areas in the world to study progradational shallow marine successions is the Campanian Book Cliffs of Utah and Colorado, where the Desert Member to Lower Castlegate Sandstone interval served as a foundational data set for early sequence stratigraphic models. A strongly progradational stack of 17 parasequences comprises the Desert–Castlegate interval. Parasequences are 6·5 to 20·7 m thick. Normally regressive coarsening-upward successions are abundant, as are flat-topped, rooted foreshore sandstones. Conformable facies contacts mark the transition between the laterally adjoining nearshore terrestrial and shallow marine deposits which are genetically, temporally and spatially linked. The width of the shoreface to inner shelf facies belts varies from 4·8 to 19·9 km per parasequence, with a mean of 12·6 km. Solitary tongue shoreline trajectories are all very low to low angle ascending regressive, varying from +0·0004° to +0·171°. Stacked shoreline system trajectories are also dominantly low angle ascending regressive, with only two descending regressive trajectories, one of which intersects the depositional slope. The predominance of ascending regressive shoreline trajectories and normal regression, rarity of high frequency sequence boundaries, regressive surfaces of marine erosion and descending regressive shoreline trajectories, and absence of third-order sequence boundaries, incised valley fill deposits and no prolonged and regionally extensive sediment bypass, all point towards increasing sediment supply as the dominant driver of the Desert–Castlegate stratal architectures, while reduced accommodation (i.e. decreasing tectonic subsidence) played a secondary role. 相似文献
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Sarah K. Schultz James A. MacEachern Octavian Catuneanu Shahin E. Dashtgard 《Sedimentology》2020,67(6):2974-3002
Variability in accommodation and sedimentation rates within a basin generates significant deviations in the along-strike stratal stacking patterns of systems tracts. This variability can lead to coeval depositional units that record the juxtaposition of transgressive (retrogradational) and regressive (progradational) stratal stacking patterns. In scenarios where transgressive and regressive units are deposited concurrently, challenges arise when attempting to correlate and place systems tracts into a sequence stratigraphic framework. In these scenarios, the maximum flooding surface records a high level of diachroneity, with the position of the surface variable throughout the stratigraphic column. In this study, Viking Formation (late Albian) deposits in the Western Canada Sedimentary Basin, central Alberta, Canada, preserve significant along-strike variability of palaeoshorelines that developed in response to autogenic processes as well as allogenic controls that were active during deposition. Specifically, structural reactivation of Precambrian basement structures during Viking deposition led to significant variability in depositional environments along the palaeoshoreline. The incremental basement reactivation of the Precambrian Snowbird Tectonic Zone influenced sedimentation patterns and the creation of anomalous zones of accommodation in localized areas of the basin. Across fault boundaries and within the anomalously thick strata, both progradational and retrogradational stacking patterns occur within broadly contemporaneous deposits, complicating the correlation of stratigraphic units. While the concomitant deposition of transgressive and regressive units has been documented in a number of modern marine analogues, the concept is rarely applied to ancient successions. By identifying along-strike variabilities in shoreline geometries and incorporating the autogenic and allogenic controls that were active during deposition, a more accurate sequence stratigraphic framework can be proposed. 相似文献
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陆相裂陷盆地层序地层构成样式分析--以泌阳凹陷核三上段为例 总被引：3，自引：0，他引：3
层序地层源于被动大陆边缘盆地 ,如何将层序地层分析应用于陆相裂陷盆地是当前一个热点课题 ,近年来国内外对陆相裂陷盆地层序的研究取得了重要的成果。可容空间和沉积物供给沿着活动断层走向和倾向上的变化是控制陆相裂陷盆地层序发育样式的两个主要因素。在走向上 ,断块中部断层活动性最强 ,构造沉降最大 ,可容空间增加速率也最大 ,沉积物大多短源供给 ,以发育 型层序为主 ,向着断端 ,断层的活动性逐渐减弱 ,上盘下降和下盘上升速率相对减小 ,形成相对低地 ,是沉积物优先通过的场所 ,以 型层序发育为主。沿着倾向上 ,靠近断层的陡坡带断层活动性强 ,位移大 ,发育 型层序 ,向着远离正断层的缓坡带 ,构造活动性逐渐减弱 ,基底沉降减小 , 型层序样式发育。 型层序的下切谷和盆底扇以及斜坡扇是良好的储集体 ,具有良好的石油勘探前景 相似文献
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提出了一种基于横向切片的地物可量测性三维重构方法,利用平面单应变换和未标定的多视图完成三维重建。通过对重构物体成像进行轮廓约束及场景约束,假设一组平行平面切割重构地物,通过单应变换得到切片的轮廓线构成物体的形状,进而恢复各层轮廓线的三维值,并加入参考高度,求得重构物体的高度。实验证明了此方法对规则与不规则物体的重建均有效,使得整个三维的求解过程具有可测量性。 相似文献
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针对城市热岛效应的演化规律问题,该文以2002年7月9日湖北武汉市的Landsat遥感影像和中分辨率成像光谱仪遥感影像为研究基础,采用归一化差分植被指数,归一化建筑指数,修正后归一化水体指数分别提取了武汉市的植被区域、建筑区域、水体区域,采用密度分割方法对武汉市白天和晚上的温度进行了分区,利用改进的间隙度维数对武汉市热环境白天和晚间的分布特征进行了研究。实验结果表明:对于城市特高温区,白天比晚上的面积大而且集中;对于城市特低温区,白天比晚间面积小而且分散;为研究城市白天和夜间的热岛效应变化提供了一定的参考依据。 相似文献
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