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Influence of mantle convection to the crustal movement pattern in the northeastern margin of the Tibetan Plateau based on numerical simulation

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Science China Earth Sciences 2018年第11期61卷 1644-1658页

作者： Aiyu ZHU dongning zhang Tao ZHU Yingxing GUO Institute of Geophysics China Earthquake Administration Key Laboratory of Seismic Observation and Geophysical Imaging Institute of GeophysicsChina Earthquake Administration

Based on the recent observations about the movement and rheological structure of the lithosphere and deformation pattern of the crust, we developed a three-dimensional finite element model for the northeastern margin of the Tibetan *** model considered the impacts of both external and internal conditions, including mantle convection, gravitational potential energy and block interactions. We compared the simulated surface movement rates to the observed GPS velocities, and the results revealed that crustal movement gradually decreased toward the edge of the plateau. The factors controlling this pattern are the interactions of adjacent blocks, gravitational potential energy of the plateau, and also mantle convection as well. Additionally,according to the observation that there was an apparent difference between the horizontal movement rate of the lithosphere and convective velocity of the underlying mantle, and also based on the results of seismic anisotropy studies that suggest different strengths and deformation regimes of the lithosphere in different tectonic blocks, we proposed that the impact of mantle convection on the lithosphere may have varied in space, and introduced a parameter named mantle convection intensity factor in numerical simulations. Our simulation results show consistent surface movement rates with GPS observations, which further supports the viewpoint of seismic anisotropy studies, i.e., the degree of coupling between the crust and mantle varies significantly among different blocks.

关键词： Northeastern margin of the Tibetan Plateau Crustal movement Mantle convection Numerical simulation

Geodynamic simulation of the WenChuan Ms8.0 and Lushan Ms7.0 earthquakes

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Geodesy and Geodynamics 2019年第1期10卷 49-57页

作者： Li Liao Jiansi Yang dongning zhang Institute of Geophysics China Earthquake Administration

The Lushan Ms7.0 earthquake, occurred on April 20th, 2013, is another strong earthquake that occurred on Longmen Mountain Faults after the Wenchuan Ms8.0 earthquake. In this paper we construct a finite element model depicting fault frictional mechanism to study the geodynamics of these two strong earthquakes. The locations of the initial rupture points and the dislocation forms of the Wenchuan earthquake and Lushan earthquake are simulated to find out the potential relationship between the two earthquakes. Simulative results show that the elevation, fault geometry, and the different rheological strengths between the Sichuan basin and Tibetan plateau play an important role in the earthquake dynamics. The dynamic simulation shows the initial rupture points are located at Yingxiu county and the rupture process is mainly along the northeast direction for the Wenchuan earthquake. In particular, the different frictional strengths caused by the fluid pressure decrease between the southern and northern segments of Longmenshan faults after the Wenchuan earthquake have affected the initial rupture point and the fault dislocation form of the Lushan earthquake, when considering the thrust of Tibetan plateau to Sichuan basin as the major dynamic source.

关键词： Finite element model Initial rupture point Dislocation form Numerical simulation

Electrical conductivities of two granite samples in southern Tibet and their geophysical implications

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Science China Earth Sciences 2017年第8期60卷 1522-1532页

作者： GUO YingXing WANG DuoJun ZHOU YongSheng LIU ZaiYang YU YingJie LI DanYang zhang dongning ZHU AiYu Institute of Geophysics China Earthquake Administration College of Earth Sciences University of Chinese Academy of Sciences The State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake Administration

There are clear differences in the electrical conductivities of the crustal granites of the Qinghai-Tibet *** these granites are among the major rock types on the Qinghai-Tibet Plateau, it is very important to detect the electrical conductivity of granites under high temperatures and pressures to study the electrical conductivity structure of this area. Using impedance spectroscopy at a frequency range of 10.1–106 Hz, the electrical conductivity of the muscovite-granite collected from Yadong was investigated at a confining pressure of 1.0 GPa and temperatures ranging from 577 to 996 K, while the electrical conductivity of the biotite-granite collected from Lhasa was investigated at a pressure of 1.0 GPa and temperatures ranging from587 to 1382 K. The calculated activation enthalpies of the Yadong muscovite-granite sample is 0.92 eV in the low-temperature range(577–919 K) and 2.16 eV in the high-temperature range(919–996 K). The activation enthalpies of the Lhasa biotite-granite sample is 0.48 eV in the low-temperature range(587–990 K) and 2.06 eV in the high-temperature range(990–1382 K). The change in the activation enthalpies of the granites at different temperature ranges may be associated with the dehydration of the two samples. The electrical conductivities of the granite samples obtained in the laboratory using impedance spectroscopy correspond well with field observations conducted near the sampling points, both in terms of the actual conductivity values and the observed variations between the low-temperature and high-temperature regimes. This correlation of laboratory and field conductivities indicates that the conductivities of the crustal rocks in the two regions closely correspond to granite *** calculated the electrical conductivities of muscovite-granite and biotite-granite samples using the effective medium and HS boundary models. When applied to the crustal rocks of southern Tibet, the results of the geophysical conductivity

关键词： Electrical conductivity High temperature and pressure Granite Southern Tibet Plateau

Numerical simulation of the segmentation of the stress state of the Anninghe-Zemuhe-Xiaojiang faults

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Science China Earth Sciences 2016年第12期59卷 384-396页

作者： ZHU AiYu zhang dongning JIANG ChangSheng Institute of Geophysics China Earthquake Administration

We established a three-dimensional finite element model of the Anninghe-Zemuhe-Xiaojiang faults region using contact surfaces of different sizes to describe the spatial segmentation characteristics of the faults. Our model is based on constraints from GPS observations, models of the crust and upper mantle, precise earthquake locations, the tectonic stress field, the slip rate of the faults, and the rheology of the lithosphere in the Sichuan-Yunnan area. Considering the influence of strong earthquakes since A.D. 1327, we analyzed the main controlling factors of the characteristics of the strong earthquakes and also studied by numerical simulation the possible areas of future earthquake risk and their relationship with tectonic stress. The numerical results showed that the gravitational potential energy of the Qinghai-Tibet Plateau and the interaction of adjacent blocks are the main kinetic factors affecting the characteristics of the tectonic stress distribution. There appears to be some correspondence between the distribution of tectonic stress and the b value; however, we also found that some low b value locations correspond to regions of lower stress. This contradiction may be the result of some comprehensive factors, such as the release of strain energy caused by strong earthquakes.

关键词： Anninghe-Zemuhe-Xiaojiang faults Stress state Gravitational potential energy b value Numerical simulation

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基于改进电导增量法的光伏最大功率点跟踪策略研究

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太阳能学报 2022年第8期43卷 82-90页

作者：张东宁机械总院集团云南省机械研究设计院昆明650031

以太阳电池的物理数学模型为研究对象,通过对太阳电池输出特性的分析,提出一种基于电导增量法的无级电压扰动叠加自适应的最大功率点跟踪(MPPT)简洁控制方法,在PSIM仿真环境下,与常规的固定步长电导增量法进行对比分析。仿真研究及实验... 详细信息

以太阳电池的物理数学模型为研究对象,通过对太阳电池输出特性的分析,提出一种基于电导增量法的无级电压扰动叠加自适应的最大功率点跟踪(MPPT)简洁控制方法,在PSIM仿真环境下,与常规的固定步长电导增量法进行对比分析。仿真研究及实验结果表明,该方法在太阳光照强度或负载突变及稳态时均能快速有效实现最大功率跟踪控制,为光伏发电MPPT控制的设计应用提供了参考。

关键词：太阳电池电导最大功率点跟踪器仿真建模阶跃响应

推进人类命运共同体建设中的世界民族融合——以Biblexcel计量分析“中华民族多元一体格局”研究成果为基础

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世界民族 2019年第5期 24-36页

作者：张东宁东北师范大学政法学院

1989年,费孝通先生凭借宏大的空间视野、翔实的历史资料提出“中华民族多元一体格局”的论断,引发学界30年愈加热烈的研究和讨论。本文按图索骥,将民族的自觉与自在作为这一论断的逻辑前提,进而梳理获得四个关联问题;随后,使用Bibexcel... 详细信息

1989年,费孝通先生凭借宏大的空间视野、翔实的历史资料提出“中华民族多元一体格局”的论断,引发学界30年愈加热烈的研究和讨论。本文按图索骥,将民族的自觉与自在作为这一论断的逻辑前提,进而梳理获得四个关联问题;随后,使用Bibexcel、Notexpress、Pajek等软件,搜集含有“多元一体”关键词的相关文献406篇,通过数据统计和分析,尤其是关键词矩阵和聚类图表,尝试解读30年来“中华民族多元一体格局”的研究历程,进而深入了解研究共同体以及四个关联问题认知的脉络与状况、发展的丰富与完善。最终,于时代变迁中发现,全球化发展和中国崛起正在丰富中华民族自觉与自在意识的内涵,使得再次瞻望“中华民族多元一体格局”研究前景时,更加深信,即使遭遇严峻的挑战,这一论断也必将在更为广阔的空间里创建新的价值,尤其会成为构建人类命运共同体过程中世界民族融合不可或缺的精神财富。

关键词：人类命运共同体多元一体费孝通中华民族文献计量

中国大陆地壳应变能密度年变化率图像与强震活动关系的初步探讨

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地震 1999年第1期19卷 26-32页

作者：张东宁许忠淮中国地震局地球物理研究所中国北京100081

以现代构造应力场和地壳运动的观测结果为约束条件，利用有限元方法计算了中国大陆地壳应变能密度年变化率。三维有限元模型采用粘弹性本构关系，包含了中国大陆主要活动断裂带。在青藏高原考虑了因高海拔地势蓄集的附加重力势能和地壳... 详细信息

以现代构造应力场和地壳运动的观测结果为约束条件，利用有限元方法计算了中国大陆地壳应变能密度年变化率。三维有限元模型采用粘弹性本构关系，包含了中国大陆主要活动断裂带。在青藏高原考虑了因高海拔地势蓄集的附加重力势能和地壳山根浮力作用。边界条件主要考虑了印度洋板块和太平洋板块对欧亚板块的挤压作用。把模拟结果与强震活动的时间和空间分布特征相比较。地壳应变能密度年变化率正、负值过渡带分别对应着龙门山断裂带、燕山一阴山构造带、天山构造带、鲜水河小江断裂带、红河断裂带、鄂尔多斯周边断裂带。而这些构造带均是历史上强地震的多发带。由应变能密度年变化率的数值估计，中国西部地震活动带的强震重复周期应该在250年左右。而华北中、南部地区的强震重复周期要长得多。

关键词：中国大陆地壳应变能密度年变化率强震活动

积极保暖干预对剖宫产所致手术源性低体温的影响

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解放军护理杂志 2018年第21期35卷 45-49页

作者：张东宁南京市浦口医院手术室江苏南京210031

目的探讨手术室积极保暖干预措施对剖宫产术后手术源性低体温的影响。方法便利抽样选择2017年1-6月在医院待产的健康产妇共120名,按照随机数字表法分为干预组(62例)和对照组(58例)。对照组产妇采用常规保暖措施,干预组产妇则由手术室护... 详细信息

目的探讨手术室积极保暖干预措施对剖宫产术后手术源性低体温的影响。方法便利抽样选择2017年1-6月在医院待产的健康产妇共120名,按照随机数字表法分为干预组(62例)和对照组(58例)。对照组产妇采用常规保暖措施,干预组产妇则由手术室护士进行输注加温液体以及强制性空气变暖毯联用的积极保暖护理措施。观察两组产妇的体核温度、低体温发生率、颤抖程度、温度舒适性以及新生儿的Apgar评分等指标。结果干预组体核温度、温度舒适性高于对照组(P0.05)。结论积极保暖干预可有效提高产妇核心温度,减少颤抖并降低其严重程度,提高产妇主观舒适度,可在临床上推广应用。

关键词：积极保暖干预剖宫产手术源性低体温

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汶川地震对芦山地震孕震环境影响的数值模拟

科学通报 2017年第17期62卷 1882-1895页

作者：郭颖星祝爱玉张东宁中国地震局地球物理研究所北京100081 中国地震局地震观测与地球物理成像重点实验室北京100081

利用有限元数值模拟方法,以汶川地震和芦山地震的野外地质调查、同震位移和汶川地震前形变观测结果为约束,分析研究了高海拔地形蓄积的重力位能作用下,中地壳低速层的存在以及中央断裂和前山断裂同时破裂的条件下汶川地震的发生对龙门... 详细信息

利用有限元数值模拟方法,以汶川地震和芦山地震的野外地质调查、同震位移和汶川地震前形变观测结果为约束,分析研究了高海拔地形蓄积的重力位能作用下,中地壳低速层的存在以及中央断裂和前山断裂同时破裂的条件下汶川地震的发生对龙门山南段孕震环境的影响.模拟计算结果显示,在一定的模型壳幔介质属性及空间结构下,龙门山断裂带西侧低速层的存在、青藏高原向四川盆地过渡带的地形特征以及汶川地震时中央断裂和前山断裂同时破裂的条件,是控制汶川地震对芦山地震孕震环境影响程度的重要因素.其中,地形和低速层对汶川地震引发的芦山地震孕震环境库仑破裂应力变化的影响最为显著,在所选剖面的北东段,地形特征的影响更为明显,而汶川地震双破裂面的影响则较小.

关键词：汶川地震芦山地震孕震环境库仑破裂应力数值模拟