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1.
Physical properties of rocks in the zone of transition from the Asian continent to the Pacific Ocean
《International Geology Review》2012,54(11):1321-1325
Velocity-density relationships in the south of Sakhalin, Primor'ye, Chukotka, Kamchatka, and the south of the Greater Kuril island arc are based on Neogene - lower Paleozoic rock samples from the part of the crust accessible to drilling. The calculated densities differ in regions with a different type of development of the crust. A comparison of the possible nature of the stresses in the crust of such regions during post-Cretaceous time suggests a similiar pattern of evolution of the crust of Japan and the south of the Kuril arc. The increased densities in the lower part of the crust in Sakhalin and Japan could evidently serve as a source of energy for the completion of future folding of this region. The disproportion of changes in the velocities of the P and S waves with change in pressure on the rock samples suggest the possibility of discriminating the predominant directions (horizontal or vertical) of past tectonic stresses. A study of the changes in velocities of the P and S waves in the tectonically weakened regions of the crust may provide information on the present stress state of the earth. —Author. 相似文献
2.
V. M. Grannik 《Doklady Earth Sciences》2012,442(2):215-219
The structural and compositional volcanosedimentary complexes and igneous rocks of the Sakhalin marginal paleobasin as well
as the geodynamic setting were described. The Sakhalin marginal paleobasin was formed in Sakhalin Island and the adjacent
water areas at the end of the Early Cretaceous-start of the Late Cretaceous. The paleobasin was a part of the Kula Plate separated
from the ocean along with spreading zones and oceanic volcanic islands by the Sea of Okhotsk microcontinent and the Jurassic-Early
Cretaceous Sheltinga volcanic island arc. The petrochemical features and geodynamic setting of the igneous rock formation
testify to the fact that magma-generating tectonomagmatic structures of the epioceanic Sakhalin marginal paleobasin continued
functioning after its isolation under intensive terrigenous sedimentation. The Sakhalin marginal paleobasin had a heterogeneous
basement composed of oceanic and continental crust blocks of the Earth. The paleobasin completed its development in the Paleogene. 相似文献
3.
《International Geology Review》2012,54(5):591-607
The vast variety of the tectonic constituents of the Pacific mobile belt displays their interdependence suggesting, as it were, a certain unified plan of reconstruction of the Earth's crust on the regional scale. However, there is evidence of novel processes in that reconstruction, during the late Tertiary-Quaternary stage, such as the general thinning of the crust in southern Sakhalin Island and elsewhere, involving an ascent of the Mohorovi?i? and Conrad discontinuities, a basaltification of the crust's consolidated complex, accompanied by downwarping of large segments of the lithosphere. In other parts of the region, the converse of these phenomena seems apparent, in the effective mutual transformation of the upper mantle and the lower crust and, within the crust, of the basaltic and granitic layers. — V. P. Sokoloff. 相似文献
4.
E. G. Ivolga N. P. Romanovskii V. G. Gurovich Yu. F. Manilov 《Russian Journal of Pacific Geology》2013,7(5):358-367
A gravity field interpretation is performed for the North Sikhote-Alin and North Sakhalin fold structures junction area using the COSCAD-3D software package, and petrodensity and petromagnetic maps are compiled, thus making it possible to obtain new data on the petrophysical features and the deep structure of the area under study. As a result of the complex geophysical and petrophysical data’s interpretation, a sketch map of the disjunctive tectonics is compiled and the circular structure featuring a unique rock fill caused by the influence exerted by the mantle’s deep structure is identified and can be considered as a magma chamber structure with the center being in the North Sakhalin Bay. 相似文献
5.
A geological density section of the Deryugin Basin (western part of the Sea of Okhotsk) was studied along the profile Sakhalin Island-Deryugin Basin-Central Okhotsk Rise. The investigations were conducted by the method of gravity modeling, which allowed us to trace the density variations of the Earth’s crust layers along the lateral. The horizontal density stratification of the Earth’s crust layers was found, which assumes a stratified-block model of its structure. The established density structure of the Earth’s crust showed that the Deryugin Basin is located in the junction zone between the Sakhalin-Hokkaido microplate and the Okhotsk Sea Plate separated by a structural suture. The western and eastern edges of the basin belong to the aforementioned plates, respectively. It was assumed that accumulations of various mineral associations are confined to the suture zone, while the “granite” layer (basement) of the Deryugin trough walls in the western edge of the Deryugin Basin presumably contains secondary reservoirs of hydrocarbons. 相似文献
6.
The results of deep seismic profiling through Southern Sakhalin, the southern Sea of Okhotsk, and the Southern Kuril Islands
allowed the identification of deep fault zones, the hypocenter locations, the features of the stress state, and the types
of seismic dislocations at the earthquake sources. The east side of the fault was upthrown relative to the west side beneath
the southern part of the Tatar Strait and Sakhalin Island and led, as a result of multiple thrusting events along the fault
over the geologic history, to the rise and 5-8 km displacement of the seismic boundaries. The true uplift of the Greater Kuril
arc block was determined using the focal mechanism solutions. The seismoctectonics and present-day dynamics of the crustal
blocks were estimated using a detailed joint analysis of the position of the structural boundaries at the seismic section
and the seismotectonic movements according to the earthquake focal mechanisms. 相似文献
7.
浅表层天然气水合物区的海底地形特征——以鄂霍次克海为例 总被引：3，自引：2，他引：1
使用重力取样器、渔网、深潜器等手段已经在海底及以下浅表层区域采获天然气水合物样品。但关于浅表层水合物的发育机制、分布规律及与海底地形的关系等问题还缺乏基本认识。根据2006年鄂霍次克海天然气水合物调查航次的调查数据,介绍了浅表层天然气水合物区的海底地形特征。萨哈林东北陆坡区,特别是中、下陆坡区发育大量海底凸起,这些凸起一般呈不对称的丘形,宽几百米,高几十米。不同于海底沙波、沙脊,海底凸起为孤立海底地形,在南北方向上并不连续。海底凸起和浅表层天然气水合物的发育密切相关。在海底剖面仪测量结果剖面上清楚地显示古陆坡凸起的发育。普遍地,现今海底陆坡凸起的幅度要小于古陆坡凸起的幅度,个别地方古、今陆坡凸起的形态有所变化,但大部分古、今陆坡凸起是一一对应的,基本形态没有根本变化。在萨哈林陆坡地区存在两个方向的挤压应力场,分别是由德鲁根盆地向萨哈林陆坡方向的挤压应力场、萨哈林陆坡沿萨哈林走滑断裂向南的挤压应力场。海底陆坡凸起是这两大应力场复合作用的结果。浊反射区中的游离气是底辟构造中的超高压多相物质向上迁移形成的。浊反射区上方对应的海底凸起应该是宏观构造挤压和局部底辟发育叠合的结果。浊反射区上方的海底凸起,在形态等方面应该和其他仅由挤压构造原因形成的凸起有所区别,比如顶部发育裂口等。在底辟构造中,由于游离气体的向上迁移,在整个水合物稳定域中从下到上,直至海底都可能形成水合物,从而使我们有机会使用重力采样器这样的设备也能采获天然气水合物样品。 相似文献
8.
The recent geodynamics of Sakhalin Island is best described by the convergence of the Eurasian and North American (Sea of
Okhotsk) lithospheric plates, which is manifested in the high seismic activity of the island. In North Sakhalin, the plate
boundary is thought to correspond to a system of roughly N-S-trending faults, which belong to the North Sakhalin deep fault,
and the Upper-Piltun fault; the latter was ruptured by the 1995 M 7.2 Neftegorsk earthquake. This study first confirmed that
the stationary motion of the Sea of Okhotsk plate is retarded on this fault to form with time a series of drag folds and stress
field anomalies. The latter are released during the subsequent (in a 400⦒o 1000-year period) strong earthquakes by seismic
sliding on the flanks of the Upper Piltun fault. The 2003–2006 GPS observations revealed the free state of this fault zone
with relative slip rates of 5–6 mm/yr. 相似文献
9.
雅鲁藏布江蛇绿岩带内多个地幔橄榄岩体产有金刚石、碳硅石等异常矿物组合,为了进一步探讨这些异常矿物形成的物理化学条件,在前人已有的研究基础上,对泽当地幔岩体中526 kg的方辉橄榄岩样品开展人工重砂矿物学研究工作。研究表明,同雅鲁藏布江蛇绿岩带内的其他岩体相似,泽当地幔橄榄岩也选出了包含金刚石、碳硅石、锆石等30余种矿物。异常矿物组合指示泽当地幔橄榄岩中存在局部的超高压、极还原环境,可能经历了复杂的演化过程:即古老地壳物质通过深俯冲或者折沉作用,进入地幔甚至是地幔过渡带(410~660 km),随后经历了超高压、极还原环境的改造,在后续的地幔柱或地幔对流作用中从洋中脊上升至浅部环境并返回到地壳中。该过程中地幔橄榄岩中的异常矿物组合记录了岩石的演化信息,因此开展地幔橄榄岩中异常矿物组合的精细矿物学研究,对认识壳-幔物质交换以及深部地幔动力学过程都有重要的研究意义。 相似文献
10.
11.
S. M. Saprygin 《Russian Journal of Pacific Geology》2008,2(2):158-164
Detailed seismic zoning of Sakhalin based on seismological, tectonic, geomorphological, hydrogeological, and other data is discussed. It is shown that strong crustal earthquakes occurred at the boundary between the Eurasian and Okhotsk plates and their recurrence in Central Sakhalin is equal to the duration of the tectonic cycle (75 years). This boundary in North Sakhalin is marked by the Upper-Piltun fault, which was the epicenter of the 1995 Neftegorsk earthquake with an intensity of 9. The analysis of paleosoils in the fault zone showed that such events repeat with an interval of 400 years. The development of large oil and gas reservoirs on the Sakhalin shelf will be accompanied by intensification of the seismicity, which can reach a magnitude of M = 6.0–6.5 in the Lunskoye field. 相似文献
12.
A.S. Zakupin Yu.N. Levin N.V. Boginskaya O.A. Zherdeva 《Russian Geology and Geophysics》2018,59(11):1526-1532
The potential of the load-unload response ratio (LURR) method for medium-term earthquake prediction is studied for Sakhalin Island as an example. An approach to the generation of predicted conditions and assessment of their implementation in real time is considered. The results of a retrospective analysis of other large Sakhalin earthquakes are used for generalization. It is shown that deviations of prediction parameters from specified values are satisfactory for this method. It is recommended that this method be used to compile summaries of medium-term predictions for Sakhalin provided that catalogs are filled as soon as possible. 相似文献
13.
地幔氧逸度与俯冲带深部碳循环 总被引：2，自引：2，他引：0
地幔氧逸度通过改变含碳相的存在形式和迁移方式来影响深部碳循环。本文结合最新的地幔氧逸度实验模拟和岩石学研究成果,探讨了地幔氧逸度时空分布对深部碳循环的影响。文章重点结合地幔减压熔融形成洋壳、新生洋壳蚀变、洋壳俯冲变质、深俯冲洋壳熔融以及俯冲洋壳物质(流体和固体)通过岩浆(岛弧和地幔柱)作用循环出地表等重要地质过程,探讨了伴随洋壳俯冲作用的深部碳循环过程。由于地幔氧逸度的时空变化,俯冲带含碳相表现出不同的存在形式和迁移能力。通过对西南天山俯冲带碳循环的岩石学和实验研究,我们认为应当进一步深入研究俯冲带氧化还原状态及其对俯冲带深部碳循环的影响。 相似文献
14.
华北和扬子陆块及秦岭-大别造山带地表和深部太古宙基底的新信息 总被引：40，自引：4，他引：36
本文根据华北和扬子陆块及秦岭-大别造山带地表和深部出露的各种岩石中发现的继承性锆石的测年数据,报道了太古宙基底和岩浆事件的新信息,并简要地论述其地质意义。华北陆块东北缘、东南缘、北缘、西北缘共6个地区的深部都存在新太古代和中、古太古代岩浆事件的新信息;南缘深部也存在古太古代岩浆事件的新信息。在华北陆块早前寒武纪同位素年龄直方图(以太古宙岩浆事件为主)上,最高峰值位于2.45-2.6 Ga区间,而以2.5-2.55 Ga最为突出,显示该区间岩浆事件最为强烈,可能代表一次重要的碰撞事件。此外还见有2.7 Ga,2.8 -2.85 Ga,2.95-3.0 Ga,3.1-3.15 Ga,3.3-3.4 Ga,3.45-3.5 Ga,3.6 Ga和3.8 Ga等较高峰值,反映了岩浆事件不同活动阶段的演化趋势。扬子陆块北缘地表和深部有与华北陆块相似的太古宙古老基底信息。扬子陆块中部的长江中下游地区、东南缘相当于江南古陆的地区以及扬子陆块西南缘地区在地壳深部均保留有新太古代和/或古太古代岩浆锆石的年龄信息。秦岭-大别造山带从东到西,多处(主要是深部)也发现有新-中太古代残余岩浆锆石的年龄信息。 相似文献
15.
大别造山带地壳的元素丰度 总被引：5，自引：1，他引：4
大别造山带具板片叠覆式构造形态。区域地壳具3个结构层,中地壳存在地震低速层和电性低阻层。地壳总体成分为花岗闪长岩质,深部地壳成分为中性。地壳稀土总量偏高、轻重稀土分馏程度高,铁族元素偏低、亲石元素富集。造山带内部横向不均一性明显,而地壳纵向演化分异程度低于一般大陆地壳。 相似文献
16.
Donna L. Whitney Clémentine Hamelin Christian Teyssier Natalie H. Raia Megan S. Korchinski Nicholas C. A. Seaton Brian C. Bagley Anette von der Handt Françoise Roger Patrice F. Rey 《Journal of Metamorphic Geology》2020,38(3):297-327
In orogens worldwide and throughout geologic time, large volumes of deep continental crust have been exhumed in domal structures. Extension-driven ascent of bodies of deep, hot crust is a very efficient mechanism for rapid heat and mass transfer from deep to shallow crustal levels and is therefore an important mechanism in the evolution of continents. The dominant rock type in exhumed domes is quartzofeldspathic gneiss (typically migmatitic) that does not record its former high-pressure (HP) conditions in its equilibrium mineral assemblage; rather, it records the conditions of emplacement and cooling in the mid/shallow crust. Mafic rocks included in gneiss may, however, contain a fragmentary record of a HP history, and are evidence that their host rocks were also deeply sourced. An excellent example of exhumed deep crust that retains a partial HP record is in the Montagne Noire dome, French Massif Central, which contains well-preserved eclogite (garnet+omphacite+rutile+quartz) in migmatite in two locations: one in the dome core and the other at the dome margin. Both eclogites record P ~ 1.5 ± 0.2 GPa at T ~ 700 ± 20°C, but differ from each other in whole-rock and mineral composition, deformation features (shape and crystallographic preferred orientation, CPO), extent of record of prograde metamorphism in garnet and zircon, and degree of preservation of inherited zircon. Rim ages of zircon in both eclogites overlap with the oldest crystallization ages of host gneiss at c. 310 Ma, interpreted based on zircon rare earth element abundance in eclogite zircon as the age of HP metamorphism. Dome-margin eclogite zircon retains a widespread record of protolith age (c. 470–450 Ma, the same as host gneiss protolith age), whereas dome-core eclogite zircon has more scarce preservation of inherited zircon. Possible explanations for differences in the two eclogites relate to differences in the protolith mafic magma composition and history and/or the duration of metamorphic heating and extent of interaction with aqueous fluid, affecting zircon crystallization. Differences in HP deformation fabrics may relate to the position of the eclogite facies rocks relative to zones of transpression and transtension at an early stage of dome development. Regardless of differences, both eclogites experienced HP metamorphism and deformation in the deep crust at c. 310 Ma and were exhumed by lithospheric extension—with their host migmatite—near the end of the Variscan orogeny. The deep crust in this region was rapidly exhumed from ~50 to <10 km, where it equilibrated under low-P/high-T conditions, leaving a sparse but compelling record of the deep origin of most of the crust now exposed in the dome. 相似文献
17.
地球深部是大规模成矿作用的“驱动机”、“供应源”和“传输带”。深入揭示深部物质组成与分布、物质循环与能量转换、三维架构与动力过程,对理解成矿作用至关重要。岩浆岩“探针”及区域同位素(如全岩Nd、锆石Hf)填图是探索深部物质组成与演化过程的主要手段,可以探测地壳深部物质组成的三维架构,揭示新生地壳/古老地壳/再造地壳的空间分布与时空演变,从而为提升区域成矿规律认识提供深部物质制约证据,有助于成矿潜力的定量半定量评价及其区域成矿预测。文章重点总结和探讨了岩浆岩全岩Nd同位素和锆石Hf同位素区域填图在解决地壳三维架构与成矿规律方面的应用成果,深入探讨了巨量岩浆岩发育的深部驱动机制及其成矿制约,对比总结了不同类型造山带(如中亚增生造山带、青藏高原碰撞造山带、秦岭复合造山带等)和不同克拉通的地壳深部组成结构与成矿制约特色。研究显示：不论是什么造山带和克拉通,深部年轻地壳分布区制约了铜金、铜镍等矿床的形成分布;古老地壳控制了大型钼矿、铅锌矿、稀有金属等矿产;两者过渡地带常常发育铁矿等。这些研究不仅揭示了区域成矿规律,而且对成矿预测与成矿潜力评价有潜在的应用价值,有可能成为成矿规律研究特别是深部物质探测及成矿背景研究的新方向。 相似文献
18.
19.
横跨银川盆地北西西向的深地震反射剖面,清晰揭示了银川盆地边界断裂以及整个地壳的结构构造特征,这对研究具活动大陆裂谷性质的银川盆地浅-深构造关系具有重大的意义。贺兰山东麓山前断裂、黄河断裂作为银川盆地的西、东边界断裂,前者为一条缓倾斜、延伸至上、下地壳边界的犁式断裂,而后者则为一条切穿地壳并延伸进入上地幔的深大断裂。根据深地震反射剖面揭示的地壳结构特征,银川盆地浅部结构并非前人认为的"堑中堑"结构,而是表现为由一系列东倾犁式正断层控制的新生代断陷。略微下凹的Moho面几何形态以及厚2~3.2 km的层状强反射带为下地壳最显著的反射特征。Moho面深度与强反射带厚度变化趋势与银川盆地沉积厚度变化趋势几乎一致。本文认为,强反射带的成因可能是由源自地幔的基性岩浆以岩席状的形式底侵进入地壳底部造成的,而这部分形成强反射带的物质可能补偿了因银川盆地断陷而造成的地壳减薄,最终导致银川盆地之下Moho面并未像之前所认为的那样隆起。 相似文献
20.
地壳中的热流体活动与油气运移 总被引：22，自引：6，他引：22
地壳中的热流体活动实际就是地壳流体作用，是最近十多年来才被认识到并发展起来的前沿科学。地壳流体起着传输能量和搬运物质的作用，是地壳中最活跃的一种营力，直接影响和控制着整个地壳的构造、沉积、成岩和成矿等作用。通过对地壳流体的研究可能产生全新的地质科学理论。油气运移是发生在沉积盆地中的热流活动，它贯穿在整个油气的生成、运移、聚集和散失过程中，直接控制着油气藏的形成并影响着盆地中的构造活动和成岩作用。研究油气运移可以为研究整个地壳流体提供一个窗口和借鉴。不连续的幕式排烃机理可以使人们联想到地壳深部的变质流体也可能呈幕式活动并产生幕式的构造运动。在深部流体活动的作用下有必要对石油的无机成因学说、热降解机理和深盆热水运移等问题重新进行评估。 相似文献