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1.
提出一个简单的假说来解释为什么在相对稳定的板块内部地区会存在高地震活动区与高构造形变区．首先,对于大多数板内地区而言,特别是大陆地盾地区与老的海洋盆地,下地壳与上地幔的温度相当低,那里的岩石相对坚硬在这些地区不可能发生明显的岩石圈变形,因为岩石图累积强度大大超过板块驱动力．相反,如果下地壳与上地幔温度相对较高,板块驱动力则主要由上地壳承受,因为下地壳与上地幔相对软弱在这种地区,由于岩石圈累积强度与板块驱动力大小相当,构造形变相对较快．本文将这种假说应用在位于美国中部的新马德里地震带与周围地区．地震带内部热流密度值约为60mw／m2,略高于本区背景热流密度值45mW／m2．计算得到的地温梯度与实验室结果所揭示的延性流动定律表明,在地震带内下地壳与上地幔相当软弱,板内应力主要由上地壳传递．那里的形变速率相对较高．与此相反,在周围地区热流值相对较低,岩石四累积强度大大超过板块驱动力,构造应力由地壳与上地幔共同承受热流值的大小和下地壳上地幔的受力状态是决定地震活动性在地震带内与周围地区强烈对比的主要因素． 相似文献
2.
R. Westaway 《Pure and Applied Geophysics》2002,159(1-3):7-62
—?During the late nineteenth century, coastal parts of northern California experienced seismicity which was more intense than at any other time in its historical record and was concentrated in Spring. The seasonal character of this anomalous seismicity was statistically significant from the 1880s, if not earlier, until the time of the great 1906 earthquake. It can be explained as a result of seasonal stress transients caused by the large seasonal sediment loads which accumulated in coastal bays that overlie active strike-slip faults, as a result of hydraulic mining of gold in inland areas. Such localised loading will increase the absolute vertical stress and reduce the absolute horizontal stress, thus facilitating shear failure by unclamping vertical fault planes. However, rather than simply influencing the timing of earthquakes which would otherwise have occurred anyway sometime later, this process appears to have affected the character of the region's seismicity, causing a sequence of magnitude 5–6 earthquakes which propagated outward from these coastal depocentres. These results have three important implications. First, the proposed physical mechanism is only feasible provided the deepest continental crust in this region has a viscosity no greater than ～1017?Pa?s, giving it a Maxwell time of the order of weeks. These observations of seasonal seismicity thus suggest that such low viscosities are reasonable, a conclusion which has been difficult to establish using other evidence. They indicate that future calculations of the stress field in this region, for instance for investigating the role of earthquake triggering, should incorporate this response by lower-crustal flow, not just the immediate elastic effect. Second, the conclusion that seasonal stress transients caused by seasonal changes in surface processes can affect seismicity, has important implications for hazard assessment. It raises the possibility that surface processes may influence the seasonal timing and character of seismicity in other regions also. Finally, it indicates that the decades of intense seismicity, widely interpreted as precursory activity to the 1906 earthquake, were atypical of the longer-term record. Analogous sequences of moderate-sized events cannot necessarily be expected to provide advance warning of future large earthquakes in this region. 相似文献
3.
The Pamir plateau, located north of the western syntaxis of the India-Eurasia collision system, is regarded as one of the most possible places of the ongoing continental deep subduction. Based on a N-S trending linear seismic array across the Pamir plateau, we use the methods of the harmonic analysis of receiver functions and the cubic spline interpolation of surface wave dispersions to coordinate their resolutions, and perform a joint inversion of these datasets to construct a 2-D S-wave velocity model of the crust and uppermost mantle there. A spatial configuration among the intermediate-depth seismicity, Moho topography, and low-velocity anomalies within the crust and upper mantle is revealed, which provides new seismological constraints on the geodynamic processes of the continental subduction. These results not only further confirm the deep subduction of the Asian continental lower crust beneath the Pamir plateau, but also indicate the importance of the metamorphic dehydration of the subducting continental crustal material in the genesis of the intermediate-depth seismicity and the crustal deformation. 相似文献
4.
T. Boldizsár 《Pure and Applied Geophysics》1970,80(1):260-266
Summary Although active volcanic territories are not characterised by extreme high heat flow, yet terrestrial heat is one of the main, if not hte first cause of volcanic activities. About 94 per cent of the known active volcanoes are in connection with orogenic zones including ocean ridges, which mean that processes responsible for the evolution of the continents cause the overwhelming majority of volcanism.There stages of the evolution of the continental crust can be distinguished: 1.) Growth of the continental cores by differentiation, 2.) Existence of peripheral growing zones around the first core, 3.) Intergrowth of the existing continents.Volcanism, as well as seismicity are manifestations of the evolution of the crust which is caused by the development of heat sources in the mantle. The heat partly melt the upper mantle and induce slow plastic flow in connection of differentiation. The space, left empty by continental uplift is filled by the slow plastic inflow of mantle from the ocean. This slow redistribution of mantle and curstal rocks disturbs the stress field, the rocks fail along the strained zones and zones of fractures appear sometimes with volcanic activity. 相似文献
5.
大量的地质和地球物理资料表明 ,年轻的大陆构造活动区的下地壳可能因热软化而出现透入性非地震式顺层韧性流动 ,这种下地壳层流作用驱动大陆上地壳发生地震式脆性断块运动 ,形成盆山格局 ,发生圈层耦合。大陆下地壳低粘度物质顺层流动可能是在地幔岩浆底侵作用为下地壳提供热能和添加幔源物质的基础上 ,并在地幔上升派生的重力和剪切力作用下 ,造成大陆下地壳热软化物质从盆地下部的幔隆区顺层流向相邻造山带之下的幔拗区。在下地壳层流过程中 ,地温场和速度场发生变 相似文献
6.
Stress field and seismicity in the Indian shield: Effects of the collision between India and Eurasia
Intraplate stresses and intraplate seismicity in the Indian subcontinent are strongly affected by the continued convergence between India and Eurasia. The mean orientation of the maximum horizontal compression in the Indian subcontinent is subparallel to the direction of the ridge push at the plate boundary as well as to the direction of compression expected to arise from the net resistive forces at the Himalayan collision zone, indicating that the intraplate stresses in the subcontinent, including the shield area, are caused by plate tectonic processes. Spatial distribution of historic and instrumentally recorded earthquakes indicate that the seismic activity is mostly confined to linear belts while the remaining large area of the shield is stable. The available conventional heat flow data and other indicators of heat flow suggest hotter geotherms in the linear belts, leading to amplification of stresses in the upper brittle crust. Many of the faults in these linear belts, which happen to be 200–80 m.y. old, are being reactivated either in a strike-slip or thrust-faulting mode. The reactivation mechanisms have been analyzed by taking into consideration the amplification of stresses, pore pressures, geological history of the faults and their orientation with respect to the contemporaneous stress field. The seismicity of the Indian shield is explained in terms of these reactivation mechanisms. 相似文献
7.
根据“网状塑性流动”大陆动力学模型,岩石圈的变形方式由浅层脆性向深层延性的转变以及岩石圈下层网状塑性流动的控制作用,导致板块内部的多层构造变形。GPS方法或断层错动反演方法所测定的只是浅表地壳。多震层的应变速率可用“地震复发间隔法”,根据先后两次地震的复发间隔和后发地震的发震概率予以估计。基于岩石圈下层塑性流动网络共轭角与挤压变形之间的关系,可运用“共轭角法”估计该层的应变,并结合对于变形时间的估计,进一步推算网络的特征应变速率。文中给出了亚洲中东部地区岩石圈下层特征应变速率的等值线图,其数量级为10-15～10-14/s。控制多震层地震活动的主要是塑性流动网带,其应变速率大于网络的特征应变速率,除此以外,多震层的应变速率还受到驱动边界的直接作用、塑性流动波和上下层之间非连续分布软弱层的影响。根据青藏高原至华北平原11个潜在震源区所在地段多震层应变速率与岩石圈下层特征应变速率的对比分析,除临汾盆地1处偏差较大外,其余10处两者间表现出显著的线性相关,其比值β平均为1.75,分布范围为1.25～2.25。文中建议在进行中长期地震预测时,可根据岩石圈下层特征应变速率等值线图,结合比值β的引入,粗略地估计各潜在震源 相似文献
8.
《Journal of Geodynamics》2003,35(1-2):173-189
The special type of intraplate microseismicity with swarm-like occurrence of earthquakes within the Vogtland/NW-Bohemian Region is analysed to reveal the nature and the origin of the seismogenic regime. The long-term data set of continuous seismic monitoring since 1962, including more than 26000 events within a range of about 5 units of local magnitude, provides an unique database for statistical investigations. Most earthquakes occur in narrow hypocentral volumes (clusters) within the lower part of the upper crust, but also single event occurrence outside of spatial clusters is observed. Temporal distribution of events is concentrated in clusters (swarms), which last some days until few month in dependence of intensity. Since 1962 three strong swarms occurred (1962, 1985/86, 2000), including two seismic cycles. Spatial clusters are distributed along a fault system of regional extension (Leipzig-Regensburger Störung), which is supposed to act as the joint tectonic fracture zone for the whole seismogenic region. Seismicity is analysed by fractal analysis, suggesting a unifractal behaviour of seismicity and uniform character of seismotectonic regime for the whole region. A tendency of decreasing fractal dimension values is observed for temporal distribution of earthquakes, indicating an increasing degree of temporal clustering from swarm to swarm. Following the idea of earthquake triggering by magma intrusions and related fluid and gas release into the tectonically pre-stressed parts of the crust, a steady increased intensity of intrusion and/or fluid and gas release might account for that observation. Additionally, seismic parameters for Vogtland/NW-Bohemia intraplate seismicity are compared with an adequate data set of mining-induced seismicity in a nearby mine of Lubin/Poland and with synthetic data sets to evaluate parameter estimation. Due to different seismogenic regime of tectonic and induced seismicity, significant differences between b-values and temporal dimension values are observed. Most significant for intraplate seismicity are relatively low fractal dimension values for temporal distribution. That observation reflects the strong degree of temporal earthquake clustering, which might explain the episodic character of earthquake swarms and support the idea of push-like triggering of earthquake avalanches by intruding magma. 相似文献
9.
Xiaozhi Yang 《Surveys in Geophysics》2011,32(6):875-903
Electromagnetic measurements have demonstrated that the lower continental crust has remarkable electrical anomalies of high
conductivity and electrical anisotropy on a global scale (probably with some local exceptions), but their origin is a long-standing
and controversial problem. Typical electrical properties of the lower continental crust include: (1) the electrical conductivity
is usually 10−4 to 10−1 S/m; (2) the overlying shallow crust and underlying upper mantle are in most cases less conductive; (3) the electrical conductivity
is statistically much higher in Phanerozoic than in Precambrian areas; (4) horizontal anisotropy has been resolved in many
areas; and (5) in some regions there appear to be correlations between high electrical conductivity and other physical properties
such as seismic reflections. The explanation based on conduction by interconnected, highly conductive phases such as fluids,
melts, or graphite films in grain boundary zones has various problems in accounting for geophysically resolved electrical
conductivity and other chemical and physical properties of the lower crust. The lower continental crust is dominated by mafic
granulites (in particular beneath stable regions), with nominally anhydrous clinopyroxene, orthopyroxene, and plagioclase
as the main assemblages, and the prevailing temperatures are mostly 700–1,000°C as estimated from xenolith data, surface heat
flow, and seismic imaging. Pyroxenes have significantly higher Fe content in the lower crust than in the upper mantle (peridotites),
and plagioclase has higher Na content in the lower crust than in the shallow crust (granites). Minerals in the lower continental
crust generally contain trace amounts of water as H-related point defects, from less than 100 to more than 1,000 ppm H2O (by weight), with concentrations usually higher than those in the upper mantle. Observations of xenolith granulites captured
by volcano-related eruptions indicate that the lower continental crust is characterized by alternating pyroxene-rich and plagioclase-rich
layers. Experimental studies on typical lower crustal minerals have shown that their electrical conductivity can be significantly
enhanced by the higher contents of Fe (for pyroxenes), Na (for plagioclase), and water (for all minerals) at thermodynamic
conditions corresponding to the lower continental crust, e.g., to levels comparable to those measured by geophysical field
surveys. Preferred orientation of hydrous plagioclase, e.g., due to ductile flow in the deep crust, and alternating mineral
fabrics of pyroxene-rich and plagioclase-rich layers can lead to substantial anisotropy of electrical conductivity. Electrical
conductivity properties in many regions of the lower continental crust, especially beneath stable areas, can mostly be accounted
for by solid-state conduction due to the major constituents; other special, additional conduction mechanisms due to grain
boundary phases are not strictly necessary. 相似文献
10.
N.B.W. Harris C.J. Hawkesworth P. Van Calsteren F. McDermott 《Earth and Planetary Science Letters》1987,83(1-4)
Nd isotopic data from the Zimbabwe and Kaapvaal cratons and the Limpopo, Kalahari, Namaqualand and Damara mobile belts imply that over 50% of present-day continental crust in this region had separated from the mantle by the end of the Archaean and that< 10% of continental crust of southern Africa has formed in the last 1.0 Ga. Such a growth rate implies that average erosion rates through geological time were high and that evolution of continental crust has been dominated by crustal growth prior to 1.4 Ga, and crustal reworking since that time. The evolution of average crust is not represented directly by clastic sediment samples but may be determined from sediment analyses if both the time of orogeneses and the average erosion rate are known. Both trace element data from southern Africa granitoids and the high erosion rates implied by the isotopic study suggest that growth of continental crust in the Archaean was by underplating rather than lateral accretion, but arc accretion was the dominant mechanism after 2.0 Ga. 相似文献
11.
《中国科学:地球科学(英文版)》2017,(3)
The Qinling-Dabie orogen is an important tectonic belt that trends east-west and divides continental China into northern and southern parts.Due to its strong deformation,complicated structure,multiphase structural superposition and the massive exposed high and ultrahigh metamorphic rocks,its tectonic formation and geodynamical evolution are hot research topics worldwide.Previous studies mainly focused on the regional geological or geochemical aspects,whereas the geophysical constraints are few and isolated,in particular on the orogenic scale.Here,we integrate the available P- and S-wave seismic and seismicity data,and construct the rheological structures along the Qinling-Dabie orogen.The results demonstrate that:(1)there are strong lateral variations in the crustal velocity between the western and eastern sections of the Qinling-Dabie orogen,indicating the different origin and tectonic evolution between these two parts;(2) the lateral variations are also manifested in the rheological structure.The rigid blocks,such as South China and Ordos basin(North China Craton),resist deformation and show low seismicity.The weak regions,such as the margin of Tibet and western Qinling-Dabie experience strong deformation and accumulated stress,thus show active seismicity;(3) in the lower crust of most of the HP/UHP terranes the values of P-wave velocity are higher than the global average ones;finally(4) low P- and S-wave velocities and low strength in the lower crust and lithospheric mantle beneath Dabie indicate lithospheric delamination,and/or high temperature,and partial melting condition. 相似文献
12.
The continental crust is exposed in cross-section at numerous sites on the earth's surface. These exposures, which appear to have formed by obduction along great faults during continental collision, may be recognized by exposures of deep crustal rocks exhibiting asymmetric patterns of metamorphic grade and age across the faults and by distinctive Bouguer anomaly patterns reflecting dipping basement structure and an anomalously deep mantle. From an examination of five complexes which meet these criteria, it is concluded that the most prominent layering in the crust is not compositional but metamorphic. The lower crust consists of granulite facies rocks of mafic to intermediate composition while the intermediate and shallow levels consist predominantly of amphibolite facies gneisses and greenschist facies supracrustal rocks, respectively. Post-metamorphic granitic intrusions are common at intermediate to shallow levels. Position of discontinuities in refraction velocity, where present, commonly correspond to changes in composition or metamorphic grade with depth. The continental crust is characterized by lateral and vertical heterogeneities of varying scale which are the apparent cause of the complex seismic reflections recorded by COCORP. Field observations, coupled with geochemical data, indicate a complex evolution of the lower crust which can include anatexis, multiple deformation, polymetamorphism and reworking of older crustal material. The complexity of the crust is thus the result of continuous evolution by recycling and metamorphism through time in a variety of tectonic environments. 相似文献
13.
14.
Thermally, the lithosphere may be defined as that outer portion of the earth in which heat is transferred primarily by conduction. It generally includes the crust and part of the mantle. The thermal regime of continental lithosphere is determined by many factors including heat flow from the asthenosphere, the vertical and lateral variation of both thermal conductivity and radiogenic heat production, tectonic history, and such superficial processes as climatic history and the shallow hydrothermal regime. From studies of the global heat flow data set, two generalizations regarding continental lithosphere have arisen, namely that: 1) there is a negative correlation between heat flow and tectonic age of continental lithosphere; and 2) the thermal evolution of continental lithosphere is similar to that of ocean basins with the result that the “stable geotherm” is similar in both environments. When continental heat-flow data are studied from a regional rather than a global point of view, considerable doubt arises as to the general applicability of either statement. R. U. M. Rao and his associates have demonstrated that while Precambrian terranes do have demonstrably lower heat flows than, say, Tertiary terranes, the data are not normally distributed and it is not possible to establish a negative correlation between heat flow and age in any rigorous statistical way. The scatter in the relation may be explained in terms of the variations in the duration, intensity and even the sign of continental thermotectonic events in contrast to the simple situation (creation of new oceanic lithosphere at mid-ocean ridges) which prevails in the oceans. The scatter also is partially attributable to the large and laterally variable radiogenic component of heat flow on continents. For a province for which a heat flow-heat production relation has been established, much of the scatter in surface heat flow due to crustal radiogenic heat production versus age is eliminated by determining reduced heat flow (surface heat flow minus radiogenic component) as a function of tectonic age, but much scatter remains, and it is still not possible to establish a heat flux-age relation in a rigorous way. Primarily because of the spatial variability in radiogenic heat production, no single geotherm can be used to characterize the thermal regime of a stable continental terrane. Thus, while some sites on stable continental blocks may have a geotherm fortuitously similar to that for old ocean basins, there is no reason to expect that this will be true generally, and many stable continental terranes will be characterized by geotherms markedly different from the geotherm for old ocean basins. 相似文献
15.
Mike Sandiford 《Earth and Planetary Science Letters》2002,201(2):309-320
The late Phanerozoic Alice Springs Orogen in central Australia is an archetypal intraplate orogen characterised by a dense, granulitic core exhumed from beneath a carapace comprising a highly radiogenic granitic mid-upper crust and sediments deposited in a shallow intracratonic basin. Exhumation occurred in large part along a crustal penetrative fault system, the Redbank Shear Zone, producing one of the largest gravity anomalies (∼150 mgal) known from the continental interiors. The lithospheric strength implied by the preservation of this anomaly for more than 300 Myr raises the intriguing conundrum of what localised the intraplate deformation in the first place. Available biostratigraphic and thermochronologic data imply bulk convergence rates of less than 1 mm/yr for the orogen as a whole, several orders of magnitude lower than typical of plate margin orogens. The thermal and mechanical evolution of intraplate orogens deformed at such low thermal Peclet numbers differs in fundamental ways from plate margin orogens. In particular, at such low thermal Peclet numbers the conductive response to exhumation of heat sources cools the mid to deep crust during progressive orogenic activity. This is consistent with the hypothesis that the density structure and associated gravity anomalies may have been locked-in by virtue of the strength acquired during the orogenic process provided that the lithospheric strength changes associated with a reduction in average crustal temperature of 20-30°C are of the same order as the forces that drive intraplate deformation. 相似文献
16.
L.B. Christiansen S. Hurwitz S.E. Ingebritsen 《Earth and Planetary Science Letters》2005,240(2):307-321
We examine 20-yr data sets of seismic activity from 10 volcanic areas in the western United States for annual periodic signals (seasonality), focusing on large calderas (Long Valley caldera and Yellowstone) and stratovolcanoes (Cascade Range). We apply several statistical methods to test for seasonality in the seismic catalogs. In 4 of the 10 regions, statistically significant seasonal modulation of seismicity (> 90% probability) occurs, such that there is an increase in the monthly seismicity during a given portion of the year. In five regions, seasonal seismicity is significant in the upper 3 km of the crust. Peak seismicity occurs in the summer and autumn in Mt. St. Helens, Hebgen Lake/Madison Valley, Yellowstone Lake, and Mammoth Mountain. In the eastern south moat of Long Valley caldera (LVC) peak seismicity occurs in the winter and spring. We quantify the possible external forcing mechanisms that could modulate seasonal seismicity. Both snow unloading and groundwater recharge can generate large stress changes of > 5 kPa at seismogenic depths and may thus contribute to seasonality. 相似文献
17.
Redistribution and export of contaminated sediment within eastern Fukushima Prefecture due to typhoon flooding 
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下载免费PDF全文 Akihiro Kitamura Hiroshi Kurikami Kazuyuki Sakuma Alex Malins Masahiko Okumura Masahiko Machida Koji Mori Kazuhiro Tada Yasuhiro Tawara Takamaru Kobayashi Takafumi Yoshida Hiroyuki Tosaka 《地球表面变化过程与地形》2016,41(12):1708-1726
Tropical cyclones expose river basins to heavy rainfall and flooding, and cause substantial soil erosion and sediment transport. There is heightened interest in the effects of typhoon floods on river basins in northeast Japan, as the migration of radiocaesium‐bearing soils contaminated by the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident will affect future radiation levels. The five main catchments surrounding FDNPP are the Odaka, Ukedo, Maeda, Kuma and Tomioka basins, but little quantitative modelling has been undertaken to identify the sediment redistribution patterns and controlling processes across these basins. Here we address this issue and report catchment‐scale modelling of the five basins using the GETFLOWS simulation code. The three‐dimensional (3D) models of the basins incorporated details of the geology, soil type, land cover, and used data from meteorological records as inputs. The simulation results were checked against field monitoring data for water flow rates, suspended sediment concentrations and accumulated sediment erosion and deposition. The results show that the majority of annual sediment migration in the basins occurs over storm periods, thus making typhoons the main vectors for redistribution. The Ukedo and Tomioka basins are the most important basins in the region in terms of overall sediment transport, followed by the other three basins each with similar discharge amounts. Erosion is strongly correlated with the underlying geology and the surface topography in the study area. A low permeability Pliocene Dainenji formation in the coastal area causes high surface water flow rates and soil erosion. Conversely, erosion is lower in an area with high permeability granite basement rocks between the Hatagawa and Futaba faults in the centre of the study area. Land cover is also a factor controlling differences in erosion and transport rates between forested areas in the west of the study area and predominantly agricultural areas towards the east. The largest sediment depositions occur in the Ogaki and Takigawa Dams, at the confluence of the Takase and Ukedo Rivers, and at the Ukedo River mouth. Having clarified the sediment redistribution patterns and controlling processes, these results can assist the ongoing task of monitoring radioactive caesium redistribution within Fukushima Prefecture, and contribute to the design and implementation of measures to protect health and the environment. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
18.
基于Ｍａｘｗｅｌｌ和Ｋｅｌｖｉｎ流变模型，以延续时间与松弛期的比值，即松弛数，作为衡量指标，对地壳、上地幔不同层次的变形属性进行了判别。结果表明，除软流圈地幔主要为粘性流动外，其上各层的情况是：在漫长的地质过程中，不仅岩石圈地幔和下地壳属于粘性，上地壳也有可能处于粘性流动状态；在延续数十年的情况下，上地壳以及岩石圈地幔都可能呈弹性状态；延续时间介乎二者，通常上地壳为弹性，下地壳和岩石圈地幔为粘性或滞弹粘性。此外，还结合变形属性的判别，就岩石圈地幔的流动和板内的驱动力远程传递等问题进行了讨论 相似文献
19.
Terrence J. Toy 《地球表面变化过程与地形》1989,14(4):289-302
Comparative erosion rates provide a rational basis for evaluating reclamation success because the work performed by erosion processes is a function of both forces and resistances operating on a surface. Sheetwash erosion data collected by the LEMI technique over several years at the Dave Johnston Mine in east-central Wyoming show that, based upon average values, there is generally little difference between the erosion rates of natural and reclaimed hillslopes at this locale. Therefore, it is permissible to infer that the reclamation programme has been successful from a geomorphic perspective. However, there is considerable variation in erosion rates about the average for individual hillslopes in both the natural and reclaimed groups. Examination of these data by hillslope element and segment show that, based upon average values, the concave elements of natural and reclaimed hillslopes experience the highest rate of sheetwash erosion. Again, however, there is considerable variation about the average and considerable erosion can occur in any element or segment of particular hillslopes. Lastly, there are seasonal oscillations of hillslope surface elevation with frost-heaving prevalent during the late autumn to early spring months and erosion prevalent during the late spring to early autumn months. 相似文献
20.
The study of the netlike earthquake distribution indicates that in the central-eastern part of Asia continent there are two network systems: the central-eastern Asia system and the southeastern China system.As interpreted by the multilayer tectonic model,they might be a manifestation of the plastic-flow network systems in the lower lithosphere,including the lower crust and the mantle lid.Each network system is enclosed by different types of boundaries,including one driving boundary and some constraining and releasing boundaries.The two plastic-flow network systems with the Himalayan and Taiwan arcs as their driving boundaries play the role of controlling the intraplate tectonic deformation,stress field,seismicity,and subdivision of tectonic units. 相似文献