The Responses of the Deformable Earth to Different Driving Forces     

Han-wei Zhang  Qiong-xian Tie  Lei Yang 《Chinese Astronomy and Astrophysics》2008,32(2):209-215

The spatial and temporal variations of the Earth deformation and the gravitational field are important both in the theoretical research and in the construction of geospatial database. The Earth deforms due to various mechanisms and the deformation further induces changes in the gravitational potential of the Earth, i.e. the deformation-induced additional potential or the Euler gravitational increment. Based on the theory of vector spherical harmonics, we discuss in this paper the Earth deformation and gravitational increment resulting from the tidal force, loading force and the stress of the Earth's surface. We write out the expression for the Euler gravitational potential increment and the relations between different Love numbers. These are all important points in the research on Earth deformation.  相似文献   

关于秦岭造山带   总被引：4，自引：4，他引：0  

张国伟  郭安林  董云鹏  姚安平 《地质力学学报》2019,25(5):746-768

纪念老一代地球科学家李四光先生,思考地球科学与大地构造学的创新发展。文章以秦岭造山带为例思考大陆复合造山及其动力学,认知概括秦岭造山带基本属性与特质,探索认识中小多板块多期洋陆俯冲造山-陆-陆板块俯冲碰撞造山的板块复合造山,并又强烈叠加复合陆内造山,造成复杂组成与结构,形成立交桥式四维流变学分层的多层非耦合动态演化的大陆复合造山带模型,及其新的演化趋势动态和构成国家人类需求的成矿成藏物质财富与宜居的地表系统环境等,期望前瞻探索认知地球发展的未来。文章还就秦岭造山带几个有争议的问题,进行简要讨论,共求新的探索研究发展。期盼学习李四光先生学术理论精华,尤其在深化发展板块构造,探索认知大陆构造与动力学方面,创新发展地质力学,以宇宙太阳系视野探索地球动力学,推动大地构造新发展。   相似文献   

The Old Red Sandstone of Britain and Ireland — a review     

《Proceedings of the Geologists' Association. Geologists' Association》2017,128(3):409-421

  相似文献   

Origin and significance of soft-sediment deformation in the Old Red Sandstone of central South Wales,UK     

《Proceedings of the Geologists' Association. Geologists' Association》2017,128(3):422-430

Vertically oriented water-escape cusps are the most common type of soft-sediment deformation structure in sandstone-rich intervals of the fluvial Brownstones and Senni Formations (Cosheston Subgroup, Daugleddau Group) of the Lower Old Red Sandstone in the central Brecon Beacons and eastern Black Mountains, South Wales. The structures are widely distributed and occur at several stratigraphical levels. They can be divided into two styles. (1) Small-scale (height less than a single bed), isolated water-escape cusps formed when loosely packed sediment deposited rapidly in flood events liquefied in advance of subsequent flood events or pulses, causing localised fluidization due to the escape of excess pore water. Inclined cusps higher in some beds confirm the relationship of this deformation style to active flood events. (2) Horizons of larger-scale (occupying the entire bed thickness), laterally continuous water-escape cusps and fold trains can be traced for hundreds of metres to kilometres and result from widespread liquefaction in response to earthquakes. A lack of overturning indicates that their formation did not coincide with active flow conditions. Further detailed mapping is needed to clarify the continuity and extent of such structures and their relationship to faults that may have been active during sedimentation. The occurrence of triggers capable of causing liquefaction in granular materials provides a greater control on the occurrence of soft-sediment deformation than do lithological controls such as grain size or interbedding of sandstone and mudstone. The findings are broadly consistent with interpretations of soft-sediment deformation in the Cosheston Subgroup in Pembrokeshire, SW Wales.  相似文献   

Basin modeling of the Late Miocene Zeit source rock in the Sudanese portion of Red Sea Basin: Implication for hydrocarbon generation and expulsion history     

《Marine and Petroleum Geology》2017

The Late Miocene Zeit Formation is exposed in the Red Sea Basin of Sudan and represents an important oil-source rock. In this study, five (5) exploratory wells along Red Sea Basin of Sudan are used to model the petroleum generation and expulsion history of the Zeit Formation. Burial/thermal models illustrate that the Red Sea is an extensional rift basin and initially developed during the Late Eocene to Oligocene. Heat flow models show that the present-day heat flow values in the area are between 60 and 109 mW/m². The variation in values of the heat flow can be linked to the raise in the geothermal gradient from margins of the basin towards offshore basin. The offshore basin is an axial area with thick burial depth, which is the principal heat flow source.The paleo-heat flow values of the basin are approximately from 95 to 260 mW/m², increased from Oligocene to Early Pliocene and then decreased exponentially prior to Late Pliocene. This high paleo-heat flow had a considerable effect on the source rock maturation and cooking of the organic matter. The maturity history models indicate that the Zeit Formation source rock passed the late oil-window and converted the oil generated to gas during the Late Miocene.The basin models also indicate that the petroleum was expelled from the Zeit source rock during the Late Miocene (>7 Ma) and it continues to present-day, with transformation ratio of more than 50%. Therefore, the Zeit Formation acts as an effective source rock where significant amounts of petroleum are expected to be generated in the Red Sea Basin.  相似文献   

磷锑钼蓝光度法测定红土镍矿中磷量          下载免费PDF全文

司银奎 《山东国土资源》2012,28(12):52-54

试样经烘干处理后,利用硫酸和氢氟酸溶矿,硝酸提取,加氨水以氢氧化铁为载体沉淀磷酸盐,分离镍、铬、钴、铜等干扰离子,制备成硝酸溶液。中和后,以钼酸铵—酒石酸锑钾为显色剂,以抗坏血酸为还原剂,显色,在700nm处测量吸光度,利用计算机拟合标准曲线计算磷含量。此方法精密度与加标回收率均能满足质量要求。  相似文献   

Decadal variations in gravity caused by a tilt of the inner core     

Mathieu Dumberry 《Geophysical Journal International》2008,172(3):921-933

  相似文献   

Finite cube elements method for calculating gravity anomaly and structural index of solid and fractal bodies with defined boundaries     

Mostafa E. Mostafa 《Geophysical Journal International》2008,172(3):887-902

In this paper, we present the finite cube elements method (FCEM); a novel numerical tool for calculating the gravity anomaly g and structural index SI of solid models with defined boundaries and variable density distributions, tilted or in normal position (e.g. blocks, faulted blocks, cylinders, spheres, hemispheres, triaxial ellipsoids). Extending the calculation to fractal objects, such as Menger sponges of different orders and bodies defined by polyhedrons, demonstrates the robustness of FCEM. In addition, approximating the cube element by a sphere of equal volume makes the calculation of gravitation and related derivatives much simpler. In gravity modelling of a sphere, cubes with edges of 100 m and 200 m achieve a good compromise between running time and overall error.
Displaying the distribution of SI of the studied models on contour maps and profiles will have a strong impact on the forward and inverse modelling of potential field data, especially for Euler deconvolution.
For Menger sponges, plots of gravity elements g and its derivatives show similar patterns independent of fractal order. Moreover, both the pattern and magnitude of SI are independent of fractal order, allowing the use of SI as a new invariant measure for fractal objects. However, SI pattern and magnitude strongly depend on the depth to the buried bodies as do other elements
In this study, we also present a new type of plot; the structural index against distance variation diagrams from which we extract the three critical SI ( CSI ) values, one per axis. The inversion of gravity anomaly data at CSI values gives the optimal mean location of the buried body.  相似文献   

红河流域气温和蒸发量时空变化分析   总被引：2，自引：0，他引：2  

王文玲  李运刚  何大明 《云南地理环境研究》2008,20(2):109-114

使用研究区44个气象站1960-2000年的逐月20cm蒸发皿蒸发量、气温的实测资料,分析了红河流域气温和蒸发量的时空变化特征。结果表明：（1）红河流域年均气温呈上升的趋势,1960-2000年间年均气温上升了约0．52℃;其中20世纪60年代和70年代气温变化不大,80年代和90年代急剧上升;季节上以夏季上升趋势最为显著,气候倾向率为0．14℃／10a。（2）红河流域年均蒸发量呈下降的趋势,40年间下降了约45．52mm;其中60年代和70年代相差不大,80年代急剧下降,到90年代有所上升;季节上以春季和夏季下降趋势显著,气候倾向率分别为-1.63mm／10a和-7．63mm／10a。（3）年均气温和蒸发量变化的趋势具有明显的空间分布差异。全流域气温的气候倾向率在-0．21℃／10a-0．35℃／10a,主要的增温区域分布在李仙江和藤条江地区。蒸发量的气候倾向率在-48mm／10a～11mm／10a,蒸发量明显减少区域主要分布在李仙江下游的江城、元江流域的楚雄、元阳、河口和盘龙河流域的文山地区。  相似文献   

��ѹ����dz�ѹ��ˮλ��ϫЧӦ���䶨������   总被引：1，自引：0，他引：1  

刘序俨  郑小菁  陈莹  张清秀  王林 《大地测量与地球动力学》2013,33(1):35-39

???????????????λ????Ч??????????????????????????  相似文献