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Earth and Planetary Physics 2021年第3期5卷 290-295页

作者： Ting Luo Wei Leng Laboratory of Seismology and Physics of Earth’s Interior/School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Chinese Academy of Sciences Center for Excellence in Comparative Planetology Beijing 100049China

The thermal structure of the continental subduction zone can be deduced from high-pressure and ultra-high-pressure rock samples or numerical ***,petrological data indicate that the temperature of subducted continental plates is generally higher than that derived from numerical *** this paper,a two-dimensional kinematic model is used to study the thermal structure of continental subduction zones,with or without a preceding oceanic *** results show that the removal of the preceding oceanic slab can effectively increase the slab surface temperature of the continental subduction zone in the early stage of *** can sufficiently explain the difference between the cold thermal structure obtained from previous modeling results and the hot thermal structure obtained from rock sample data.

关键词： thermal structure continental subduction zone slab breakoff numerical model

Responses of thermal structure and vertical dynamic structure of South China Sea to Typhoon Chanchu

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Journal of Hydrodynamics 2014年第3期26卷 458-466页

作者：陈宜展詹杰民罗莹莹韦永康唐灵 Department of Applied Mechanics and Engineering Sun Yat-sen University Department of Civil and Environmental Engineering The Hong Kong Polytechnic University

The response of the South China Sea（SCS） to Typhoon Chanchu（2006） was examined using the MM5 and POM model. In the POM model, sea surface boundary conditions were forced by the simulation wind field from MM5, the velocity forcing was introduced in the eastern boundary and the computational schemes of heat fluxes at the surface were introduced. Comparison with the observation data shows that the simulated results are reliable. In the response process of the SCS to Typhoon Chanchu, the influence of the heat fluxes on thermal structure of the SCS was regionally different. Strong wind forcing would lead to upwelling phenomenon in the lateral boundary of deep water basin. Furthermore, the Ekman pumping theory was used to discuss subsurface upwelling and downwelling phenomenon in typhoon forced stage.

关键词： South China Sea(SCS) typhoon thermal structure vertical dynamic structure Mesoscale Model 5(MM5) princeton ocean model(POM)

Comparative Study of Magmatism in East Pacific Rise Versus Nearby Seamounts:Constraints on Magma Supply and thermal structure Beneath Mid-ocean Ridge

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Acta Geologica Sinica(English Edition) 2011年第6期85卷 1286-1298页

作者： ZHANG Guoliang Key Laboratory of Marine Geology and Environment Institute of Oceanology Chinese Academy oJ Sciences Qingdao266071 China

Major elements of 2202 basalts from the East Pacific Rise （EPR） and 888 basalts from near- EPR seamounts are used to investigate their differences in magma crystallization pressures and mantle melting conditions. Crystallization pressure calculation from basalts with 5.0wt%〈MgO〈8.0wt % shows that magma crystallization pressures beneath near-EPR seamounts are positively and negatively correlated with Nas and Fes, respectively. However, these correlations are indistinct in axial lavas, which can be explained by chemical homogenization induced by extensive mixing processes. In each segment divided by major transforms and over-lapping spreading centers （OSCs）, near-EPR seamount lavas have higher magma crystallization pressures, higher Fes and lower Nas than the EPR lavas, which indicate cooler lithosphere, lower degrees and shallower melting depths beneath near-EPR seamounts than the EPR. The correlations between magma crystallization pressures and melting conditions beneath near-EPR seamounts imply that the source thermal state controls the melting degree and melt flux, and then melting process controls the shallow lithosphere temperature and magma crystallization depth （pressure）. The cooler mantle sources beneath near-EPR seamounts produce a lower degree of melting and a less robust magma supply, which results in a deep thermal equilibrium level and high magma crystallization pressure. The magma crystallization pressure decreases significantly as spreading rate of the EPR increases from ~80 mm/year in the north （16~N） to ~160 mm/year in the south （19~S）, while this trend is unobvious in near-EPR seamounts. This suggests that the magma supply controlled by spreading rate dominates the ridge crust temperature and magma crystallization depth, while the near-EPR seamount magma supply is not dominated by the axial spreading rate. Because most seamounts form and gain most of their volume within a narrow zone of 5-15 km from ridge axis, they provide good constraint on magma

关键词： crystallization pressure magma supply thermal structure seamount East Pacific Rise

THE VERTICAL thermal structure OF THE INDIAN OCEAN DIPOLE MODE FROM WOCE DATA

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Journal of Hydrodynamics 2001年第3期13卷 24-27页

作者： Yu Wei-dong Key Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, First Institute of Oceanography, Qingdao 266061, China First Inst. of Oceanography State Oceanic Administration Qingdao 266061 China

The Dipole Mode in tropical Indian Ocean (DMI) is a newly verified independent internal mode of atmosphere ocean system in Indian Ocean. Its surface manifestation is illustrated in detail with the aid of the historical data sets. But relatively few is known about its vertical characteristics. Here the vertical thermal structure of DMI is analyzed using the newly released WOCE GLOBAL DATA (V2.0). Attention is focused on the comparison of the abnormal upper ocean thermal structure along one section with the normal state in year 1990 respectively in two cases: in year 1994 when there was IDM but no E1 Nino and in year 1997 when there were DMI and also E1 Nino. This may shed light on the further theoretical and numerical study of IDM.

关键词： DMI thermal structure

thermal structure and Rheology of the Upper Mantle Derived from Mantle Xenoliths from Gansu Province, Western China

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Earthquake Research in China 2004年第3期18卷 281-299页

作者： ShiLanbin LinChuanyong ChenXiaode InstituteofGeology ChinaEarthquakeAdministrationBeijing100029China

Mantle xenoliths brought up by Cenozoic volcanic rocks onto the earth’s surface may provide direct information about the upper mantle beneath the volcanic region. This paper presents the study on mantle xenoliths collected from Haoti village, Dangchang County, Gansu Province, western China. The main purpose of the study is to gain an insight into the thermal structure and rheology of the upper mantle beneath the region. The results show that the upper mantle of the region is composed mainly of spinel lherzolite at shallower depth (52～75km), and garnet lherzolite at greater depth (greater than 75km), instead of harzburgite and dunite as proposed by some previous studies. The upper mantle geotherm derived from the equilibrium temperatures and pressures of xenoliths from the region is lower than that of North China, and is somewhat closer to the Oceanic geotherm. The crust-mantle boundary is determined from the geotherm to be at about 52km, and the Moho seems to be the transition zone of lower crust material with spinel lherzolite. If we take 1280℃ as the temperature of the top of asthenosphere, then the lithosphere-asthenosphere boundary should be at about 120km depth. The differential stress of the upper mantle is determined by using recrystallized grain size piezometry, while the strain rate and equivalent viscosity are determined by using the high temperature flow law of peridotite. The differential stress, strain rate and viscosity profiles constructed on the basis of the obtained values indicate that asthenospheric diapir occurred in this region during the Cenozoic time, resulting in the corresponding thinning of the lithosphere. However, the scale and intensity of the diapir was significantly less than that occurring in the North China region. Moreover, numerous small-scale shear zones with localized deformation might occur in the lithospheric mantle, as evidenced by the extensive occurrence of xenoliths with tabular equigranular texture.

关键词： Mantle xenoliths Upper mantle thermal structure Rheology Gansu Province Western China

Geodynamic modeling of thermal structure of subduction zones

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Science China Earth Sciences 2015年第6期58卷 1070-1083页

作者： LENG Wei MAO Wei Laboratory of Seismology and Physics of Earth's Interior School of Earth and Space SciencesUniversity of Science and Technology of China National Geophysical Observatory at Mengcheng

During subduction processes, slabs continuously have heat exchange with the ambient mantle, including both conduction and advection effects. The evolution of slab thermal structure is one of the dominant factors in controlling physical and chemical property changes in subduction zones. It also affects our understanding of many key geological processes, such as mineral dehydration, rock partial melting, arc volcanism, and seismic activities in subduction zones. There are mainly two ways for studying thermal structure of subduction zones with geodynamic models: analytical model and numerical model. Analytical model provides insights into the most dominant controlling physical parameters on the thermal structure, such as slab age, velocity and dip angle, shear stress and thermal conductivity, etc. Numerical model can further deal with more complicated environments, such as viscosity change in the mantle wedge, coupling process between slabs and the ambient mantle, and incorporation of petrology and mineralogy. When applying geodynamic modeling results to specific subduction zones on the Earth, there are many factors which may complicate the process, therefore it is difficult to precisely constrain the thermal structure of subduction zones. With the development of new quantitative methods in geophysics and geochemistry, we may obtain more observational constraints for thermal structure of subduction zones, thus providing more reasonable explanations for geological processes related to subduction zones.

关键词： subduction zones thermal structure analytical model numerical model

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Seasonal evolution of circulation and thermal structure in the Yellow Sea

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Chinese Journal of Oceanology and Limnology 2005年第3期23卷 269-274页

作者：庞重光白学志白虹王凡 Institute of Oceanology Chinese Academy Sciences Qingdao 266071 China

In this paper, the authors used the Princeton Ocean Model (POM) to simulate the seasonal evolu- tions of circulation and thermal structure in the Yellow Sea. The simulated circulation showed that the Yellow Sea Warm Current (YSWC) was a compensation current of monsoon-driven current, and that in winter, the YSWC became stronger with depth, and could flow across the Bohai Strait in the north. Sensitivity and control- ling tests led to the following conclusions. In winter, the direction of the Yellow Sea Coastal Current in the sur- face layer was controlled partly by tide instead of wind. In summer, a cyclonic horizontal gyre existed in the middle and eastern parts of the Yellow Sea below 10 m. The downwelling in upper layer and upwelling in lower layer were somehow similar to Hu et al. (1991) conceptual model. The calculated thermal structure showed an obvious northward extending YSWC tongue in winter, its position and coverage of the Yellow Sea Cold Water Mass in summer.

关键词： seasonal evolution numerical simulation circulation thermal structure the Yellow Sea

The transport of water in subduction zones

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Science China Earth Sciences 2016年第4期59卷 651-682页

作者： ZHENG YongFei CHEN RenXu XU Zheng ZHANG ShaoBing School of Earth and Space Sciences University of Science and Technology of China

The transport of water from subducting crust into the mantle is mainly dictated by the stability of hydrous minerals in subduction zones. The thermal structure of subduction zones is a key to dehydration of the subducting crust at different depths. Oceanic subduction zones show a large variation in the geotherm, but seismicity and arc volcanism are only prominent in cold subduction zones where geothermal gradients are low. In contrast, continental subduction zones have low geothermal gradients, resulting in metamorphism in cold subduction zones and the absence of arc volcanism during subduction. In very cold subduction zone where the geothermal gradient is very low(?5?C/km), lawsonite may carry water into great depths of ?300 km. In the hot subduction zone where the geothermal gradient is high(>25?C/km), the subducting crust dehydrates significantly at shallow depths and may partially melt at depths of <80 km to form felsic melts, into which water is highly dissolved. In this case, only a minor amount of water can be transported into great depths. A number of intermediate modes are present between these two end-member dehydration modes, making subduction-zone dehydration various. Low-T/low-P hydrous minerals are not stable in warm subduction zones with increasing subduction depths and thus break down at forearc depths of ?60–80 km to release large amounts of water. In contrast, the low-T/low-P hydrous minerals are replaced by low-T/high-P hydrous minerals in cold subduction zones with increasing subduction depths, allowing the water to be transported to subarc depths of 80–160 km. In either case, dehydration reactions not only trigger seismicity in the subducting crust but also cause hydration of the mantle wedge. Nevertheless, there are still minor amounts of water to be transported by ultrahigh-pressure hydrous minerals and nominally anhydrous minerals into the deeper mantle. The mantle wedge overlying the subducting slab does not partially melt upon water influx

关键词： Subduction zones Oceanic crust Mantle wedge thermal structure Hydrous minerals Water transport Arc magmatism

Three-dimensional thermo-rheological structure of the lithosphere in the North China Craton determined by integrating multiple observations: Implications for the formation of rifts

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Science China Earth Sciences 2020年第7期63卷 969-984页

作者： Kai WANG Xiong XIONG Yuming ZHOU Yashan FENG State Key Laboratory of Geodesy and Earth’s Dynamics Institute of Geodesy and GeophysicsChinese Academy of SciencesWuhan 430074China Institute of Geophysics and Geomatics China University of GeosciencesWuhan 430074China Department of Earth and Atmospheric Sciences Saint Louis UniversityMO 63108USA

The lithosphere of the North China Craton(NCC)has experienced significant destruction and deformation since the Mesozoic,a notable feature of which is the widespread extensional structure and lithospheric thinning in the eastern *** the thermo-rheological structure of the lithosphere is one of the main factors controlling these dynamic processes,a threedimensional thermo-rheological model of the present lithosphere in the NCC was developed based on a geophysical-petrological method using a variety of data,and its relationship with the extensional structures and the formation of rifts was further *** results show that the western NCC is characterized by thick lithosphere,low Moho temperature(TMoho1).The deformation of the western narrow rift is consistent with the localized deformation dominated by the strength of lithospheric *** the other hand,the lithosphere in the eastern NCC is characterized by extensive thinning(with lithospheric thickness of about 80–110 km).However,the decrease of lithospheric strength is not uniform,with high strength(10×1012 Pa m)observed in some areas(such as the Bohai Bay Basin and Hehuai Basin).Most of the eastern lithosphere is characterized by high TMoho(600–750°C)and low Sm/Sc(structure in the eastern *** results from palaeo-geothermal and petrological studies,we developed a thermo-rheological structure model of the lithosphere at different evolutionary stages of the NCC,and suggested that the eastern NCC had a significantly thinned and weakened lithosphere in the early stages of the formation of the rift,leading to a regional distributed extension deformation dominated by crustal strength,which eventually evolved into a series of wide ***,the cooling and accretion of the lithosphere in the subsequent stages significantly increased the strength of the

关键词： North China Craton thermal structure Rheological structure Lithospheric deformation Rift

Effects of horizontal mixing on the upper ocean temperature in the equatorial Pacific Ocean

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Acta Oceanologica Sinica 2012年第1期31卷 16-23页

作者： HUANG Chuanjiang QIAO Fangli First Institute of Oceanography State Oceanic AdministrationQingdao 266061China

The influence of horizontal mixing on the thermal structure of the equatorial Pacific Ocean is examined based on a sigma coordinate model. In general, the distributions of the temperature and currents simulated by the sigma coordinate model are very close to the climatology. However, the simulated thermocline along the equator is slightly diffusive so that there is a cold bias above the main thermocline, while there is a warm bias under the main thermocline. Both horizontal diffusivity and viscosity have important effects on the upper thermal structure in the equatorial Pacific Ocean, while their detailed dynamics are different. Horizontal diffusivity affects the thermal structure in the upper ocean mainly through regulating the vertical diffusivity, while the horizontal viscosity does mainly through regulating directly the circulate system. A large horizontal diffusivity or a small horizontal viscosity can be in favor of simulating a more realistically thermal structure in the equatorial Pacific Ocean.

关键词： horizontal mixing thermal structure equatorial Pacific Ocean