东辛油田沙三中亚段沉积特征与油藏分布规律          下载免费PDF全文

陈秀艳  姜在兴  师晶  徐杰 《沉积与特提斯地质》2010,30(4):19-23

东辛油田沙三中亚段发育大量与三角洲前缘滑塌相伴生的坡移浊积扇、滑塌浊积扇、远源浊积岩以及洪水成因的水下碎屑流,发育岩性油藏及岩性-构造油藏。纵向上,湖退体系域早期准层序组PS7～PS5是最主要的油气富集层位,其次为湖侵体系域PS8;平面上,各准层序组西部油气富集程度好于东部,含油储层主要为滑塌浊积扇及部分远源浊积岩,其次为坡移浊积扇。油气分布主要受宏观沉积相带、构造、微观储集物性和成岩作用等多种因素控制,距油源远近控制油藏纵向有利层位,砂体成因类型控制着平面有利区带。  相似文献   

Measuring the speed of gravity at short distances: Sensitivity estimate     

Carlos Frajuca  Fabio da Silva Bortoli  Natan Vanelli Garcia  Nadja Simao Magalhaes 《Astronomische Nachrichten》2024,345(2-3):e230177

An experimental set up was proposed to determine the speed of gravitational signals traveling in air or in some other medium. It involves two vibrating masses—the emitters, which will be the sources of periodic tidal gravitational signals—and one sapphire-made mass that will act as a detector, positioned between the two emitters. The detector is planned to be suspended in vacuum and cooled down to 4.2 K, and its vibrational amplitude should be measured by a microwave signal (with ultra-low phase-noise) that is expected to resonate with the whispering gallery modes inside the detector. The mechanical and electrical quality factors of sapphire are quite high, yielding a very narrow detection band that reduces the detector sensitivity while amplifying the phase difference of the emitters' signals. The frequencies of the normal modes of the detector were previously determined using a finite element program. In this work, these frequencies are applied to the calculation of a first estimate of the sensitivity of the experiment.  相似文献   

Turbidite system architecture and sedimentary processes along topographically complex slopes: the Makran convergent margin     

JULIEN BOURGET  SEBASTIEN ZARAGOSI  NADINE ELLOUZ‐ZIMMERMANN  NICOLAS MOUCHOT  THIERRY GARLAN  JEAN‐LUC SCHNEIDER  VALENTINE LANFUMEY  SIGFRIED LALLEMANT 《Sedimentology》2011,58(2):376-406

This study investigates the morphology and Late Quaternary sediment distribution of the Makran turbidite system (Makran subduction zone, north‐west Indian Ocean) from a nearly complete subsurface mapping of the Oman basin, two‐dimensional seismic and a large set of coring data in order to characterize turbidite system architecture across an active (fold and thrust belt) margin. The Makran turbidite system is composed of a dense network of canyons, which cut into high relief accreted ridges and intra‐slope piggyback basins, forming at some locations connected and variably tortuous paths down complex slopes. Turbidite activity and trench filling rates are high even during the Holocene sea‐level highstand conditions. In particular, basin‐wide, sheet‐like thick mud turbidites, probably related to major mass wasting events of low recurrence time, drape the flat and unchannellized Oman abyssal plain. Longitudinal depth profiles show that the Makran canyons are highly disrupted by numerous thrust‐related large‐scale knickpoints (with gradients up to 20° and walls up to 500 m high). At the deformation front, the strong break of slope can lead to the formation of canyon‐mouth ‘plunge pools’ of variable shapes and sizes. The plunge pools observed in the western Makran are considerably larger than those previously described in sub‐surface successions; the first insights into their internal architecture and sedimentary processes are presented here. Large plunge pools in the western Makran are associated with large scoured areas at the slope break and enhanced sediment deposition downstream: high‐amplitude reflectors are observed inside the plunge pools, while their flanks are composed of thin‐bedded, fine‐grained turbidites deposited by the uppermost part of the turbidity flows. Thus, these architectural elements are associated with strong sediment segregation leading to specific trench‐fill mechanisms, as only the finer‐grained component of the flows is transferred to the abyssal plain. However, the Makran accretionary prism is characterized by strong along‐strike variability in tectonics and fluvial input distribution that might directly influence the turbidite system architecture (i.e. canyon entrenchment, plunge pool formation or channel development at canyon mouths), the sedimentary dynamics and the resulting sediment distribution. Channel formation in the abyssal plain and trench‐fill characteristics depend on the theoretical ‘equilibrium’ conditions of the feeder system, which is related closely to the balance between erosion rates and tectonic regime. Thus, the Makran turbidite system constitutes an excellent modern analogue for deep‐water sedimentary systems with structurally complex depocentres, in convergent margin settings.  相似文献   

南海海盆重力异常场特征及构造演化   总被引：5，自引：0，他引：5  

姚运生  姜卫平  晁定波 《大地构造与成矿学》2001,25(1):46-54

卫星重力测高能提供高分辩率的空间重力异常资料。本文解译了南海地块细结构的重力异常特征 ,并探讨了南海海盆的形成与演化  相似文献   

重磁异常界面反演中的计算方法   总被引：2，自引：0，他引：2  

王海燕  吴燕冈  焦新华 《世界地质》2001,20(4):379-383

迭代法和子空间法为重力异常界面反演最优化求解计算的两种方法。传统的最优化计算立意虽然简单明确，但迭代计算过程中必须的简化使得求解不稳定，加进一些限制条件之后，使计算量明显增大，以致使求解变得困难。通过引入子空间计算在矩阵求解中减少了工作量，使得加约束的最优化计算变得容易实现。通过理论分析，表明利用子空间方法的解的计算结果准确且效率较高。  相似文献   

试析小流域土力类粘性泥石流的汇流过程——以滇东北大凹子沟为例     

陈宁生  韩文喜  何杰  鄢和琳 《山地学报》2001,19(5):418-424

在分析土力类泥石流的产流特征和规律，尤其是土源与水源关系的基础上，将水文学上常用的等流时线法的基本原理应用于小流域土力类粘性泥石流的汇流计算。在具体的计算中，以滇东北蒋家沟的一支沟－大凹子沟1994－06－16的泥石流为例进行泥石流汇流流量过程的试算。计算的结果应用观测的一些数值及现象和弯道超高的最大流量计算值检验，结果表明此计算大体可以定量地反映该流域流量的过程。通过此汇流计算还可以了解阵性泥石流与连续泥石流的产生关系和机理，也可以了解降雨时段与产流时段及汇流过程时段的差别。该研究的结果也存在主客观的局限性，这一局限性反映了进一步探讨流域的产流量规律、流域等流时区划分的规律、大流域汇流计算和泥石流的波坦化规律的必然性。  相似文献   

Ocean island densities and models of lithospheric flexure     

T. A. Minshull  PH. Charvis 《Geophysical Journal International》2001,145(3):731-739

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Gravity anomalies, crustal structure and thermo-mechanical support of the Himalaya of Central Nepal     

R. Cattin  G. Martelet  P. Henry  J. P. Avouac  M. Diament  T. R. Shakya 《Geophysical Journal International》2001,147(2):381-392

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Simulation of oceanic bottom pressure for gravity space missions     

J. Wünsch  M. Thomas  Th. Gruber 《Geophysical Journal International》2001,147(2):428-434

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山西五台地区壳内低速体的重力异常的研究   总被引：1，自引：0，他引：1  

方盛明  余钦范 《地震地质》1995,17(2):109-113

运用健全的极大似然法对山西五台地区中、下地壳中存在的低密度（低速度）异常体进行了三维反演，求出该异常体的空间赋存状况，并结合浅层局部重力负异常及其它地球物理特征进行地质解释，还就其形成机制进行了讨论  相似文献