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Acta Geologica Sinica(English Edition) 2011年第1期85卷 211-222页

作者： ZHANG Keliang wei dongping College of Earth Science Graduate University of the Chinese Academy of Sciences Beijing 100049 China

For the purpose of investigating the influence of metastable olivine（MO） phase transformations on both deep seismicity and stagnation of slabs,we constructed a 2-dimensional finite element thermal model for a 120 Ma-old 50°dipping oceanic lithosphere descending at 10 cm/yr with velocity boundary layers,which would mitigate the interference of constant velocity field for the slab. The resulting temperatures show that most of intermediate and deep earthquakes occurring within the Tonga slab are occurring inside the 800℃and 1200℃isotherm,*** elevation of olivine transformation near～410 km and respective persistence of metastable olivine and spinel within the transition zone and beneath 660 km would thus result in bimodal positive,zonal,negative density anomalies,*** results together with the resulting pressure anomalies may reflect the stress pattern of the Tonga slab：（i） slab pull force exerts above a depth of～230 km;（ii） MO existence changes the buoyancy force within the transition zone and facilitates slab stagnation at a depth of 660 km;（iii） as the subducting materials accumulated over 660 km,deepest earthquakes occur due to MO transformation;（iv） a flattened‘slab’ may penetrate into the lower mantle due to the density increment of Sp transformation.

关键词： kinematic thermal model subduction zone velocity boundary layer metastable olivine,double seismic zone finite element method

夏秋高温干旱对不同下种时间甘蔗产量性状的影响

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热带作物学报 2025年第1期46卷 135-142页

作者：吴炫柯贾若欣何燕蒋春云韦剑锋韦冬萍刘志平柳州市气象局/柳州市农业气象试验站广西柳州545003 广西壮族自治区气象科学研究所广西南宁530022 广西凤糖生化股份有限公司广西柳州545002 广西科技大学广西柳州545006 柳州工学院广西柳州545616

近年来在全球气候变暖加剧的背景下,广西极端天气频发,夏秋高温少雨干旱发展加重,严重影响甘蔗生产,科学选择适宜的下种时间,是应对夏秋干旱灾害的一个重要途径。本研究于2021、2022年在广西柳州沙塘国家农业气象试验站设置甘蔗农田试验... 详细信息

近年来在全球气候变暖加剧的背景下,广西极端天气频发,夏秋高温少雨干旱发展加重,严重影响甘蔗生产,科学选择适宜的下种时间,是应对夏秋干旱灾害的一个重要途径。本研究于2021、2022年在广西柳州沙塘国家农业气象试验站设置甘蔗农田试验点,采用3个甘蔗品种,2—5月进行7期分期下种田间试验,通过利用这2个年度典型的夏秋高温干旱年景,研究夏秋高温干旱对不同下种时间甘蔗产量性状的影响。试验结果表明:(1)在夏秋高温干旱年景条件下,随着下种时间的延迟,甘蔗收获期茎长、茎粗、单茎重、理论产量均呈现明显下降的趋势,2021、2022年下种时间A1各品种茎长为178~227 cm,茎粗为27.6~30.3 mm,单茎重为1.05~1.42 kg,下种时间A7各品种茎长仅为76~145 cm,茎粗为21.5~30.0 mm,单茎重为0.26~0.85 kg;(2)在3月种植的新植蔗,理论产量在76.65~104.10 t/hm^(2)之间,甘蔗能利用前期比较适宜的气象条件,缓解夏秋高温干旱对甘蔗的影响;在4—5月期间种植的新植蔗,受干旱影响较大,其中5月30日下种理论产量仅为18.90~63.75 t/hm^(2),甘蔗产量显著下降;(3)甘蔗品种ROC22和GL05136在茎长、单茎重和理论产量方面比GT42有优势,但是在茎粗方面GT42有优势,ROC22和GL05136抗旱性较强。因此,在夏秋高温干旱年景下,选择适宜抗旱品种,春种甘蔗尽量适时提早种植,加快甘蔗前期生长进度;在夏秋干旱来临之前,获得健壮植株,提高自身抗旱能力,将气象灾害影响降到最低,可达到高产、稳产的目的。

关键词：甘蔗分期下种气象因子抗旱性高温干旱

基于^(15)N示踪技术的甘蔗不同季节播种对氮肥利用效率影响研究

同方期刊数据库博看期刊评论

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核农学报 2025年第2期39卷 369-376页

作者：韦剑锋韦冬萍胡桂娟罗小芬吴炫柯胡文莉黄锴霖马纪广西科技大学广西柳州545006 柳州工学院广西柳州545616 柳州市农业气象试验站广西柳州545005

为促进甘蔗(Saccharum spp.)氮肥高效利用,以甘蔗品种桂糖42号为材料,采用田间微区^(15)N示踪技术分析秋季(8月20日)、春季(2月20日)和夏季(5月20日)播种甘蔗的氮肥利用效率及去向。结果表明,3个播期新植蔗吸收的N有21.56%~33.93%来自... 详细信息

为促进甘蔗(Saccharum spp.)氮肥高效利用,以甘蔗品种桂糖42号为材料,采用田间微区^(15)N示踪技术分析秋季(8月20日)、春季(2月20日)和夏季(5月20日)播种甘蔗的氮肥利用效率及去向。结果表明,3个播期新植蔗吸收的N有21.56%~33.93%来自当季施用的氮肥,氮肥利用率、残留率和损失率分别为16.84%~21.50%、42.71%~47.45%和31.05%~39.43%;宿根蔗吸收的N来自上季施用氮肥的比率为6.65%~9.16%,上季氮肥在宿根季的利用率、残留率和损失率分别为4.15%~6.58%、30.25%~31.26%和8.31%~9.61%。3个播期两季甘蔗氮肥残留均随土层深度的增加而大幅递减,但0~40 cm土层残留以夏季播种较多,40~60 cm土层残留以秋季播种较多。秋季播种两季蔗茎干物质积累量为59693.69 kg·hm^(-2),较春季、夏季播种增加2.74%和34.43%;夏季播种两季甘蔗的氮肥利用率为28.08%,较秋季、春季播种提高4.63和6.58个百分点;春季播种两季甘蔗的氮肥损失率为47.85%,较秋季、夏季播种增加1.54和7.19个百分点。可见,甘蔗秋季播种产量较高,夏季播种氮肥吸收较多、损失较少,但夏季播种新植蔗吸收的大量氮肥未能转化为增产效应。本研究结果可为优化广西甘蔗氮肥施用提供科学依据。

关键词：甘蔗播种期 ^(15)N示踪氮肥利用氮素残留

维普期刊数据库博看期刊

Correlation between plate age and layer separation of double seismic zones

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Earthquake Science 2012年第1期25卷 95-101页

作者： Keliang Zhang and dongping wei State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China Key Laboratory of Computational Geodynamics Chinese Academy of SciencesBeijing 100049China College of Earth Science Graduate University of Chinese Academy of SciencesBeijing 100049China

Global seismicity catalogs are sufficient for characterizing double seismic zones （DSZs） in subducting slab and facilitate to estimate layer separation without inconsistent uncertainties as local catalogs. Previous studies have shown the correlation between DSZs layer separation and plate age while correlation for those younger than -60 Ma is suspicious. The lacking of DSZs with layer separation less than 10 km further makes it difficult to precisely estimate such correlation. Thus, we incorporate eight DSZs data determined through local seismicity into globally-determined dataset and reexamine such correlation. The best fitting results show that both a linear model and a square root of plate age can mathematically fit the layer separation well. However, it is difficult to distinguish these two models when plate age is greater than -20 Ma since their difference is less than 2 km. However, if extrapolation is possible, both models should provide physical information that DSZs will not form if there is no subducting lithosphere. As a result, the DSZs cannot be produced until the oceanic lithospheric age becomes greater than 0.9 Ma in the square root model while the linear model gives a misleading result. As such the square root model demonstrates the relationship physically better than the linear one, it still needs further test in the future with more available data, nevertheless, our study might also provide evidence for the suggestion that the plate age is a primary control factor of the DSZs geometry as well as the subducting process which disregards any local tectonic stresses.

关键词： double seismic zone layer separation plate age correlation best fitting

Implicit expansion rate of the Earth in global plate motions

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Geodesy and Geodynamics 2019年第3期10卷 228-234页

作者： Changyi Xu Xiao Yu dongping wei Institute of Earthquake Forecasting China Earthquake AdministrationBeijingChina Institute of Earth Sciences Academia SinicaTaipeiTaiwan Key Laboratory of Computational Geodynamics University of Chinese Academy of SciencesBeijingChina

Based on eight published plate motion models, we separately estimated the net area changes of tectonic plates and the area change of the solid Earth surface over geological time using the Euler vectors of plates with determined boundaries. Then, under the context of a currently expanding Earth, we inferred the change rate of the Earth’s mean radius from the estimated net area changes. The results show that the total increases and decreases in the areas of different plates cannot be compensated. Specifically, the area of the Northern Hemisphere decreases while that of the Southern Hemisphere increases, but the net area of the solid Earth surface slightly increases in th computing period(0.01 Ma). For the latest NNRMORVEL56 plate motion model, the area of the Southern Hemisphere increases by 7802 km2 while the area of the Northern Hemisphere decreases by 7711 km^2. This indicates a net area increase of 91 km2 in the solid Earth surface corresponding to an expansion rate of 0.06 mm/a for the Earths mean *** result coincides with the slow rate of expansion derived from geodetic measurements and geophysical modeling.

关键词： Plate motion model Area change of plate boundary Earth expansion

Near-surface Geothermal Gradient Observation and Geothermal Analyses in the Xianshuihe Fault Zone,Eastern Tibetan Plateau

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Acta Geologica Sinica(English Edition) 2017年第2期91卷 414-428页

作者： LIU Qianqian SHI Yanan wei dongping HAN Peng CHEN Shunyun LIU Peixun LIU Liqiang Key Laboratory of Computational Geodynamics Chinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake Administration

The Xianshuihe fault（XSHF） zone, characterized by intense tectonic activity, is located at the southwest boundary of the Bayan Har block, where several major earthquakes have occurred, including the 2008 Wenchuan and the 2013 Lushan earthquakes. This study analysed underground temperature sequence data for four years at seven measuring points at different depths（maximum depth： 18.9 m） in the southeastern section of the XSHF zone. High-frequency atmospheric noise was removed from the temperature sequences to obtain relatively stable temperature fields and heat fluxes near the measurement points. Our measurements show that the surrounding bedrock at（the seven stations distributed in the fault zone） had heat flux values range from-41.0 to 206 m W/m^2, with a median value of 54.3 m W/m^2. The results indicate a low heat flux in the northern section of DaofuKangting and a relatively high heat flux in the southern section of Kangting, which is consistent with the temperature distributions of the hot springs near the fault. Furthermore, our results suggest that the heat transfer in this field results primarily from stable underground heat conduction. In addition, the underground hydrothermal activity is also an obvious factor controlling the geothermal gradient.

关键词： temperature sequence records geothermal gradient heat flow heat flux Xianshuihe fault zone Tibet Plateau Proto-Tethys

Lattice-Preferred orientations of olivine in subducting oceanic lithosphere derived from the observed seismic anisotropies in double seismic zones

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Earthquake Science 2016年第4期29卷 243-258页

作者： Peng Han dongping wei Keliang Zhang Zhentian Sun Xiaoya Zhou Key Laboratory of Computational Geodynamics Chinese Academy of Sciences Beijing 100049 China College of Earth Science University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029China Beijing Geotherm Research Institute Beijing 100143 China

Subduction zones can generally be classified into Mariana type and Chilean type depending on plate ages, plate thicknesses, subduction angles, back-arc deformation patterns, etc. The double seismic zones （DSZs） in sub- duction zones are mainly divided into type I and type II which, respectively, correspond to the Mariana type and Chilean type in most cases. Seismic anisotropy is an important parameter characterizing the geophysical fea- tures of the lithosphere, including the subduction zones, and can be described by the two parameters of delay time ~t and fast wave polarization direction ~b. We totally col- lected 524 seismic anisotropy data records from 24 DSZs and analyzed the statistical correlations between seismic anisotropy and the related physical parameters of DSZs. Our statistical analysis demonstrated that the fast wave polarization directions are parallel to the trench strike with no more than 30~ for most type I DSZs, while being nearlyperpendicular to the trench strike for type II DSZs. We also calculated roughly linear correlations that the delay time 6t increases with dip angles but decreases with subduction rates. A linear equation was summarized to describe the strong correlation between DSZ＇s subduction angle DSZ and seismic anisotropy in subduction zones. These results suggest that the anisotropic structure of the subducting lithosphere can be described as a possible equivalent crystal similar to the olivine crystal with three mutually orthogonal polarization axes, of which the longest and the second axes are nearly along the trench-perpendicular and trench-parallel directions, respectively.

关键词： Seismic anisotropy Double seismic zonesSubduction zone processes Plate motions Microstructures

A Discussion on Correlations of Plate Motion with Seismic Anisotropy and Stress Field in Plate Boundary Zones

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Earthquake Research in China 2015年第3期29卷 319-330页

作者： Han Peng Liu Qianqian Sun Zhentian wei dongping Key Laboratory of Computational Geodynamics Chinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences Shaanxi Branch of China Geological Exploration Center of Building Materials Industry Beijing Geotherm Research Institute

In many parts of the global plates,including subduction zones,mid-ocean ridges and even the interior of the continental plates,seismic anisotropy has a certain correlation with image of absolute plate motion( APM),or is in accord with the predominant direction of the intraplate stress field. In our study,a statistical analysis is done on the correlations of plate motion with seismic anisotropy as well as a stress field within nine plate boundaries which contain major subduction zones in the globe. Results indicate that absolute or relative plate motion( RPM) controls the seismic anisotropy and stress field of the plate boundary,which is especially obvious for the RPM. It can also be inferred that the correlation of RPM is better than that of APM. Because of the complexity of subduction mechanism and diversity of controlling factors at plate boundaries containing subduction zones,the correlation becomes much complex. Sources of anisotropy at various depths show different characteristics,and stress state is controlled by many factors,thus further discussions on the correlations are required.

关键词： Seismic anisotropy Plate motion Stress field Correlation

Preface to the special issue on recent advances of deep structure,seismic anisotropy and seismotectonics in China

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Earthquake Science 2012年第1期25卷 1-2页

作者： dongping wei Fenglin Niu Yuan Gao Xuzhang Shen College of Earth Science Graduate University of Chinese Academy of SciencesBeijing 100049China Department of Earth Science Rice UniversityHoustonTX 77005USA Institute of Earthquake Science China Earthquake AdministrationBeijing 100036China Lanzhou Institute of Seismology China Earthquake AdministrationLanzhou 730000China

A workshop on crustal structure and seismotectonics was held on the Chinese Teacher＇s Day, the September 10th of 2011, in the city Lanzhou, China. Scientists and graduate students from Chinese Academy of Sciences, China Earthquake Administration, Chinese Academy of Geological Sciences, and Japan Agency for Marine-Earth Science and Technology delivered over 20 oral presentations, with topics covering crustal and upper mantle structure, seismic anisotropy, recent earthquakes and seismotectonics,

关键词： Preface special issue deep structure seismotectonics

Global Plate Motions and Their Impact on the Earth's Surface Area Change

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Earthquake Research in China 2010年第3期24卷 344-352页

作者： Cao Shuai Zhang Keliang wei dongping Laboratory of Computational Geodynamics Graduate University of the Chinese Academy of Sciences Beijing 100049 China

Based on their Euler poles, we calculated the relative velocities between every two plates in the typical global plate motion models, respectively, and estimated the area change along these boundaries. In our calculations, plates on both sides accommodated area changes depending on the boundary types： extensional, convergent or transform, so we can estimate area change of each plate and then globally. Our preliminary results show that the area of the southern hemisphere increased while that of the northern hemisphere decreased over the past I million years, and global area has increased by 26,000km^2 to 36,000km^2, which corresponds to the 160m - 250m increment on the Earth＇s radius if all these area increments are attributed to Earth＇s expansion. Taking the NUVEL-1 model as an example, of the 14 plates in this model, 11 are decreasing, but the global area has increased because of the larger increment amount from Africa, North America and Antarctica. Finally, we also discussed factors affecting the global area change such as subduction zone retreating and back-arc spreading.

关键词： Plate Motions NUVEL-1 Model Pacific Plate Subduction