南大西洋洋中脊板块构造运动过程:古地磁的约束

海底磁异常的形态与洋中脊两侧板块的微运动或变形密切相关.因此,这方面的研究可为确定板块运动的演化历史、小尺度的动力学过程以及洋中脊分段的机制等提供重要约束.本文对南大西洋一段洋中脊(31°S—34.5°S)两侧的磁异常的偏度进行了系统研究.结果表明研究区域内扩张方向并不总是垂直于洋中脊走向,并且研究区域不同剖面的扩张方向也不一致,具体表现为从北向南,平均扩张方向逐渐增加,依次为33.6°±5.3°、62.8°±13.0°以及94.3°±8.0°.这表明洋中脊的倾斜扩张机制具有复杂性,初步解释应该与转换断层的剪切应力增加有关.深部辉长岩层倾斜和扩张速率不对称性对海底磁异常偏度的影响值得深入研究.另外,由北向南确定的欧拉极向东移动,表明洋中脊两侧的板块在6.5 Ma期间存在剧烈形变.     

青藏高原东南缘构造旋转的古地磁学证据

本文在总结青藏高原东南缘近年来地质研究进展的基础上,从古地磁学的角度讨论其新生代以来的构造运动特征.结果表明:相对稳定的欧亚大陆,新生代以来山泰地块发生了约20°～80°顺时针旋转,局部地区旋转量甚至高达135°,且中部地区的旋转量明显高于南北地区;印支地块经历了～30°的顺时针旋转;川滇地块的顺时针旋转量沿102°E经度线由南向北由30°逐渐减小;另一方面,古地磁数据还揭示出山泰地块新生代以来发生了～8°的南向滑移运动.旋转量随时间的变化表明主要构造旋转发生在始新世与中中新世之间,与哀牢山—红河断裂的左行走滑时间相一致.这表明青藏高原东南缘的新生代构造运动具有差异性和复杂性,现今国际流行的挤出逃逸、地壳缩短增厚及下地壳流模式均有其局限性.值得注意的是,青藏高原东南缘可靠的新生代古地磁数据在时空分布上的严重不足,制约了我们对印度与欧亚大陆碰撞在青藏高原东南缘的运动学响应过程的深入探讨和正确理解.因此,进一步对该地区新生代地层开展深入细致的古地磁学等综合研究,无疑具有重要的科学意义.     

Paleomagnetic dating of Phanerozoic kimberlites in Siberia

Diamond bearing kimberlite pipes are exposed across the north-central part of the Siberian platform. Three main time intervals are considered to be the age of emplacement: the Devonian–Early Carboniferous, Triassic, and Cretaceous. However, isotopic age data from of the pipes are scattered and provide a very broad age interval for the magmatic activity. New paleomagnetic poles from four kimberlite pipes (Eastern Udachnaya, Western Udachnaya, International and Obnazhennaya) are obtained to estimate their paleomagnetic age. The mean primary magnetization directions for the pipes are as follows: D = 4.3°, I = − 44.5° (k = 29.4, α₉₅ = 7.4°, N = 14); D = 340.5°, I = − 65.6° (k = 12.9, α₉₅ = 19.4°, N = 6); D = 291.1°, I = − 78.1° (k = 27.5, α₉₅ = 14.9°, N = 5); and D = 306.7°, I = − 82.6° (k = 38.4, α₉₅ = 5.8°, N = 17), respectively. On the basis of a comparison with the Siberian apparent polar wander path (APWP) we estimate the age of kimberlite magmatism, assuming primary magnetizations in these rocks. The paleomagnetic ages are as follows: 428 ± 13 Ma for Eastern Udachnaya; 251 ± 30 Ma for International pipe; and 168 ± 11 Ma for Obnazhennaya pipe. The Western Udachnaya pipe was remagnetized and no clear paleomagnetic age could be determined. The ages of magmatic activity span the Early Silurian to Middle Late Jurassic. Early Silurian magmatism could be associated with the formation of the Viluy rift. Middle to Late Jurassic magmatic activity is most likely related to subduction related to the accretion of surrounding terranes to Siberia.     

Apparent polar wander path and tectonic movement of the North China Block in Phanerozoic

The results on the Early Paleozoic from the North China Block (NCB) are reported. and a series of reliable poles are selected from the available Phanerozoic data, based on the conventional reliability criteria, e.g. the number of samples, the uncertainty limit, any suspected incomplete demagnetization or overprint and field test (including fold, reversal, conglomerate tests). Especially, paleopole data is excluded if the sampling area suffered from the tectonic (e.g. rotation) and thermal effects. A new Phanerozoic apparent polar wander (APW) path for the NCB is compiled, and its tectonic evolution is discussed.     

西秦岭东段对青藏高原东向扩展过程构造响应的古地磁制约

为探究青藏高原东向扩展隆升过程中"十字构造"枢纽处西秦岭各部分的变形特征,在舟曲、武都、成县和凤县等地区下白垩统和新近系中开展了详细的古地磁研究.获得了舟曲和成县地区的早白垩世古地磁极(舟曲85.7°N,279.8°E,A95=9.1°;成县72.3°N,226.3°E,A95=6.8°),以及武都地区的新近纪古地磁极(65.8°N,206.1°E,A95=12.8°).将其分别与同时代的华北地区古磁极进行对比后表明：(1)早白垩世之后,舟曲地区相对于华北发生了14.7±5.8°的逆时针局部构造旋转;(2)成县地区早白垩世古地磁极与华北参考极一致;(3)新近纪之后,武都地区相对于华北参考极发生了25.1±5.6°的顺时针局部构造旋转.结合前人成果,我们认为：青藏高原向东扩展演化过程在西秦岭地区的构造响应,各构造部位展示出不同的活动特征.北西侧区域表现为左行走滑断裂,控制断裂两侧地块呈现原地顺时针旋转,与青藏高原东北部地区的动力机制一致;南西侧区域主体受控于松潘甘孜北东向挤压逆冲,并在北东向次生走滑断裂作用下平移错动,伴随断裂附近的拖曳变形,导致局部逆时针转动;东部区域早期走滑断裂形成拉分盆地,晚期受挤压应力改造,边界断裂发生构造翻转,盆地内弱变形.     

Paleomagnetic constraints on Miocene rotation in the central Japan Arc

We present new Middle Miocene paleomagnetic data for the central Japan Arc, and discuss their implications for Miocene rotation. To obtain a refined paleodirection, we made magnetic measurements on basaltic to andesitic lavas and intrusive rocks from 12 sites in the Tsugu volcanic rocks (ca 15 Ma) in the northern part of the Shitara area, Japan. Significant secondary magnetizations in samples with strong magnetic intensities are interpreted as lightning‐induced components. Mean directions carried by magnetite and/or titanomagnetite were determined for all sites. An overall mean direction with a northerly declination was obtained from dual‐polarity site means for nine sites. This direction is indistinguishable from the mean direction for coeval parallel dikes in the northern part of the Shitara area, and also indistinguishable from the Miocene reference direction derived from the paleopole for the North China Block in the Asian continent. These comparisons suggest little or no rotation or latitudinal motion in the study area with respect to the North China Block since 15 Ma. We obtained a refined early Middle Miocene paleodirection (D = 9.7°, I = 52.5°, α₉₅ = 4.8°; 30 sites) and paleopole (82.0°N, 230.8°E, A₉₅ = 5.6°) for Shitara by combining data from the Tsugu volcanic rocks and a coeval dike swarm. An anomalous direction found at three sites could be a record of an extraordinary field during a geomagnetic polarity transition or excursion. Paleomagnetic data from Shitara suggest that: (i) the western wing of the Kanto Syntaxis, a prominent cuspate geologic structure in central Honshu, underwent a counterclockwise rotation with respect to the main part of the southwestern Japan Arc between ca 17.5 Ma and 15 Ma; (ii) collision between the Japan and Izu–Bonin (Ogasawara) Arcs began prior to 15 Ma; and (iii) clockwise rotation of the entire southwestern part of the Japan Arc had ceased by 15 Ma.     

New paleomagnetic constraints on the late Cretaceous and early Cenozoic tectonic history of the Eastern Pontides

The Pontides are characterized by a series of Mesozoic-Cenozoic fold belts comprising a N-vergent foreland fold and thrust belt in the Western Pontides and a concave, upward-shaped fold belt in the Eastern Pontides. The curvature of the fold belt follows the Caucasus which may imply a phase of oroclinal bending. In order to test whether the fold curvature represents a phase of oroclinal bending, a paleomagnetic study has been carried out in the Eastern Pontides on late Cretaceous and middle Eocene volcanic and sedimentary rocks from 29 sites. Rock magnetic studies reveal medium-temperature components with an unblocking temperature of 400–580 °C, indicating pseudo-single domain titanomagnetite as the most abundant carrier of magnetic remanence in the middle Eocene rocks studied here. In the upper Cretaceous rocks, a high-temperature component with an unblocking range of 580–650 °C was isolated. Stepwise thermal and alternating field demagnetization isolated two components of remanent magnetization in middle Eocene rocks comprising a low unblocking temperature/coercivity component near the present field direction and a characteristic remanent magnetization (ChRM) component of D_s = 332.3°, I_s = 49.9° (k = 33.3, α₉₅ = 9.2°, N = 15 sites). A positive fold test at a 95% confidence level and a reversal test indicate a primary magnetization. Component analysis of the upper Cretaceous rocks identifies a stable ChRM D_s = 160.3°, I_s = −45.0°, (k =  85.6, α₉₅ = 6.0°, N =  8 sites) following removal of secondary remanence. Their ChRM direction passes fold and reversal tests at a 95% confidence level. Both the upper Cretaceous and middle Eocene paleomagnetic data from the Eastern Pontides and the Lesser Caucasus clearly demonstrate evidence of oroclinal bending that occurred contemporaneouslywith the convergence between Arabia and Eurasia in the Paleocene.     

中国西部及邻区活动地块边界带现代构造应力场

利用哈佛全球矩心矩张量解数据和许忠淮认为1920mdash;1999年可靠的中国大陆震源机制解数据, 反演了中国西部及邻区活动地块边界带上现代构造应力场．通过对FMSI反演程序多次的输入和检验, 得到了边界带上的应力场．边界带上最大主压应力sigma;1轴绝大多数近水平. 在90deg;E以西的中国西部大陆及邻区, sigma;1轴水平方向基本上为近SN向;在青藏高原的东北部, sigma;1轴水平方向基本上为近NE向;在青藏高原的东南部, sigma;1轴水平方向绕喜马拉雅构造东端顺时针方向旋转．最小主压应力sigma;3轴倾角呈两极分布,西域地块区内活动地块边界带和青藏地块区内东北缘部分段sigma;3轴倾角较陡, 而青藏地块区内sigma;3轴倾角近水平, 所以西域地块区和青藏地块区内东北部相对于其它大部分青藏地块区, 有更多的逆冲地震．应力场在同一个边界带具有非均匀性. 北天山带、南天山带、西秦岭mdash;德令哈带、岷山mdash;龙门山带和安宁河mdash;小江带的非均匀性相对要小一些, 西昆仑带、海原mdash;祁连带、东昆仑带、玛尼mdash;玉树带、澜沧江带和滇西西边界带的非均匀性相对要大, 而喀喇昆仑mdash;嘉黎带和喜马拉雅带的非均匀性最显著．由于震源机制解数据的限制, 本文给出的是边界带上部分段的应力场．      

Active tectonic blocks and strong earthquakes in the continent of China

The primary pattern of the late Cenozoic to the present tectonic deformation of China is characterized by relative movements and interactions of tectonic blocks. Active tectonic blocks are geological units that have been separated from each other by active tectonic zones. Boundaries between blocks are the highest gradient of differential movement. Most of tectonic activity occurs on boundaries of the blocks. Earthquakes are results of abrupt releases of accumulated strain energy that reaches the threshold of strength of the earth’s crust. Boundaries of tectonic blocks are the locations of most discontinuous deformation and highest gradient of stress accumulation, thus are the most likely places for strain energy accumulation and releases, and in turn, devastating earthquakes. Almost all earthquakes of magnitude greater than 8 and 80%–90% of earthquakes of magnitude over 7 occur along boundaries of active tectonic blocks. This fact indicates that differential movements and interactions of active tectonic blocks are the primary mechanism for the occurrences of devastating earthquakes.     

黑龙江省饶河枕状玄武岩古地磁学研究及其构造意义

蛇绿岩中枕状玄武岩的古地磁学研究可为古海洋的恢复与演化提供定量化依据.黑龙江省饶河地区中侏罗世枕状玄武岩的岩石学、岩石磁学研究表明,该岩石具备水下喷出特点,发育辉长结构,载磁矿物为磁铁矿.17个采点181块样品的热退磁实验表明,中侏罗世枕状玄武岩记录了高温分量和中温分量,前者为熔岩喷发记录的原生剩磁方向,平均方向D/I=59.4°/46.3°,α95=6.8°,对应的极位置为40.3°N,224.6°E,A95=7°;后者可能为晚侏罗世—早白垩世岩浆热事件的叠加,平均方向D/I=55.4°/60.6°,α95=3.9°,对应的极位置为50.8°N,210.6°E,A95=5.2°.综合考虑区域地质背景,将这一结果与邻区同时代的古地磁数据对比,推测在中侏罗世之前,在饶河杂岩与佳木斯地体之间存在一定规模的海域,与现今日本海相似;早白垩世时期,该海域封闭,饶河杂岩与华北、西伯利亚板块在动力学上已成为整体.     

Active tectonic blocks and strong earthquakes in the continent of China

The primary pattern of the late Cenozoic to the present tectonic deformation of China is characterized by relative movements and interactions of tectonic blocks. Active tectonic blocks are geological units that have been separated from each other by active tectonic zones. Boundaries between blocks are the highest gradient of differential movement. Most of tectonic activity occurs on boundaries of the blocks. Earthquakes are results of abrupt releases of accumulated strain energy that reaches the threshold of strength of the earth's crust. Boundaries of tectonic blocks are the locations of most discontinuous deformation and highest gradient of stress accumulation, thus are the most likely places for strain energy accumulation and releases, and in turn, devastating earthquakes. Almost all earthquakes of magnitude greater than 8 and 80%-90% of earthquakes of magnitude over 7 occur along boundaries of active tectonic blocks. This fact indicates that differential movements and interactions of active tectonic blocks are the primary mechanism for the occurrences of devastating earthquakes.     

Paleomagnetic constraints on the late Cretaceous and Cenozoic tectonics of southeastern Asia

Many features of the Cenozoic tectonic history of central and southeastern Asia can be understood as direct consequences of the thrust and penetration of India into Asia. Recent indentation experiments with plasticine (Tapponnier et al. [7]) have extended this idea and have led to the prediction of a pattern of large rotations and displacements of continental blocks that can be tested by paleomagnetism. The available Cretaceous and Cenozoic paleomagnetic data from this part of the world have been reviewed and a new APWP for Eurasia has been constructed for reference. The negligible rotation of South China and large clockwise rotation of Indochina are consistent with the model, i.e., with an history of large-scale left-lateral strike-slip motion along the Altyn Tagh and Red River faults. Data from Malaya and Borneo can be reconciled with the model, although in a less straightforward fashion. The large counter clockwise rotation of South Tibet implies that it rotated in sympathy with India during the collision and suggests that future indentation experiments should include this feature. Finally a middle Cretaceous reconstruction of the south margin of Asia is proposed. One interesting result is the restored continuity of geological features in Tibet and Indochina, with active subduction of oceanic (Indian plate) crust taking place to the south at subtropical latitudes.     

Paleomagnetic constraints on eruption patterns at the Pacaya composite volcano,Guatemala

Pacaya volcano is an active composite volcano located in the volcanic highlands of Guatemala about 40 km south of Guatemala City. Volcanism at Pacaya alternates between Strombolian and Vulcanian, and during the past five years there has been a marked increase in the violence of eruptions. The volcano is composed principally of basalt flows interbedded with thin scoria fall units, several pyroclastic surge beds, and at least one welded tuff. Between 400 and 2000 years BP the W-SW sector of the volcano collapsed producing a horseshoeshaped amphitheater (0.65 km³) and providing a window into the cone's infrastructure. Lava flows and tephra exposed in the amphitheater are more then 200 m thick and when combined with flows erupted recently represent between 30 and 40% of the cone's history. Pacaya is ideally suited for a paleomagnetic study into the timing and duration of eruption episodes at a large, composite volcano. We drilled 27 paleomagnetic sites (25 aa flows, 1 dike, and 1 welded tuff) from four lava-flow sequences with between 4 and 14 sites per sequence. The four sequences represent initial through historic activity at Pacaya. We resolved, what appear to be, 22 time-independent paleomagnetic sites by averaging together directions from successive sites where the sitemean directions were indistinguishable at the 95% level of confidence. However, mean-sequence directions of individual lava-flow sequences yielded unusually high Fisher precision parameters (k=44–224) and small circles of 63% confidence (a₆₃=1.6–6.1°) suggesting as few as three or four time-independent sites were collected. This indicates that activity as Pacaya is strongly episodic and that episodes are characterized by voluminous outpouring of lavas. Modelling the data using Holocene PSV rates confirms this and shows that differences in within-sequence directions (6–11.5°) are consistent with emplacement of lava-flow sequences in less than 100 years to as many as 300 years. Relatively larger differences in directions (18–23°) between subjacent lava-flow sequences indicates that repose is at least 300–500 years and could be even longer.     

华北不同构造块体地壳结构及其对比研究

华北古大陆块体经多期构造运动的改造使地壳构造具有明显的分块特征. 利用华北地区近30条、共约两万公里的深地震测深资料及成果,进一步研究华北各次级块体内部地壳细结构,对比分析各块体的结构差异. 根据不同的地壳结构特征,华北地壳可分为三大类：西部鄂尔多斯盆地地壳结构简单,基底结构完整,为稳定古大陆地壳;华北中部隆起区太行山及北部阴山、燕山隆起区地壳结构相对简单,中部地壳和下地壳局部区域轻微速度逆转,可能与该区域地壳增厚隆升的壳内介质解耦形变有关;华北东部裂陷盆地地壳结构复杂, 基底下陷、破碎,壳内介质松散、速度低,Moho上隆、地壳减薄,横向结构差异明显,显示了新生地壳构造特征. 在此基础上,综合研究、探讨了华北地壳分块构造以及与之相关的动力学演化.     

黑龙江东部白垩纪-古近纪古地磁初步结果及其构造意义

陆内块体旋转是周边构造环境和深部构造活动相互作用的结果.前人研究表明华北东部和俄罗斯远东地区晚中生代以来的块体旋转样式,很可能以牡丹江断裂为界发生了显著变化.进一步对牡丹江断裂两侧块体晚中生代以来的块体旋转样式的限定,有助于正确理解这一差异旋转的机制.对采自黑龙江省东部白垩纪和古近纪岩石的(51个采点)古地磁学研究表明,相对于稳定欧亚大陆,牡丹江断裂东侧的佳木斯地块内部的穆棱、鸡西、七台河和桦南地区旋转样式一致,整体发生了30°~40°的逆时针旋转,逆时针旋转很可能发生在晚白垩世末之后.华北东部及俄罗斯远东地区的差异性相对旋转很可能与白垩纪以来太平洋板块的俯冲作用和作为深俯冲带的牡丹江断裂的重新活化有关.     

Sedimentary fill history of the Huicheng Basin in the West Qinling Mountains and associated constraints on Mesozoic intracontinental tectonic evolution

The Qinling Orogenic Belt is divided commonly by the Fengxian-Taibai strike-slip shear zone and the Huicheng Basin into the East and West Qinling mountains,which show significant geological differences after the Indosinian orogeny.The Fengxian-Taibai fault zone and the Meso-Cenozoic Huicheng Basin,situated at the boundary of the East and West Qinling,provide a natural laboratory for tectonic analysis and sedimentological study of intracontinental tectonic evolution of the Qinling Orogenic Belt.In order to explain the dynamic development of the Huicheng Basin and elucidate its post-orogenic tectonic evolution at the junction of the East and West Qinling,we studied the geometry and kinematics of fault zones between the blocks of West Qinling,as well as the sedimentary fill history of the Huicheng Basin.First,we found that after the collisional orogeny in the Late Triassic,post-orogenic extensional collapse occurred in the Early and Middle Jurassic within the Qinling Orogenic Belt,resulting in a series of rift basins.Second,in the Late Jurassic and Early Cretaceous,a NE-SW compressive stress field caused large-scale sinistral strike-slip faults in the Qinling Orogenic Belt,causing intracontinental escape tectonics at the junction of the East and West Qinling,including eastward finite escape of the East Qinling micro-plate and southwest lateral escape of the Bikou Terrane.Meanwhile,the strike-slip-related Early Cretaceous sedimentary basin was formed with a right-order echelon arrangement in sinistral shear zones along the southern margin of the Huicheng fault.Overall during the Mesozoic,the Huicheng Basin and surrounding areas experienced four tectonic evolutionary stages,including extensional rift basin development in the Early and Middle Jurassic,intense compressive uplift in the Late Jurassic,formation of a strike-slip extensional basin in the Early Cretaceous,and compressive uplift in the Late Cretaceous.     

New constraints on the tectonic evolution of the eastern Indian Ocean

From marine magnetic anomaly studies, a fossil spreading ridge is identified beneath the Nicobar Fan in the northwestern Wharton Basin. Several north-south-trending transform faults offset this ridge left-laterally east of the 86°E transform fault. Our findings show that this ridge, which was part of the plate boundary between the Indian and Australian plates, ceased its spreading shortly after formation of magnetic anomaly 20 (～ 45.6m.y. B.P.). Since the breakup of Australia and Antarctica probably occurred sometime between 110 and 90 m.y. B.P., we suggest that the Indian, Australian, and Antarctic plates were moving relative to one another from about 90 to 45 m.y. B.P. A triple junction would have existed in the southeastern Indian Ocean during that period of time. At anomaly 19 time (～ 45m.y. B.P.), the junction became inactive, and Australia and India became a single plate. The northwest-southeast-trending Southeast Indian Ridge was formed by connecting the India-Antarctica spreading center with the Australia-Antarctica spreading center. Its activity has continued to the present time.     

Paleomagnetic study on the Early Triassic red beds from Jiaocheng, Shanxi Province--Local rotation and tectonic significance

Paleomagnetic and rock magnetic study has been conducted on the Early Triassicred beds of Liujiagou Formation from Jiaocheng, Shanxi Province. Hematite was shown as themain magnetic mineral. After eradicating an initial viscous component at room temperature to～100℃-200℃, thermal demagnetization shows that most samples contain two remanencecomponents, intermediate-temperature remanence component at 250℃-500℃ and high-tem-perature component at 500℃-680℃. The intermediate-temperature component has a negativefold test at the 95% confidence level. And the pole position of the intermediate-temperaturecomponent in geographic coordinates is correlated with the Middle Jurassic reference pole of theNorth China Block (NCB) within the 95% confidence, suggesting that it might be a remagnetiza-tion component acquired during the Yanshanian period. The high-temperature component con-tains both reversal and normal polarities with positive fold test and C-level positive reversal test atthe 95% confidence level, which suggests that this high-temperature component can be regardedas primary magnetization. Comparison of this newly obtained Early Triassic paleopole with thecoeval mean pole of the Ordos Basin suggests that a locally relative rotation may have happenedbetween the Ordos and the Jiaocheng area of Shanxi Province. This rotation may be related withtwo faults: one is Lishi big fault separating Ordos from Shanxi and the other is Jiaocheng big fault,which is situated in the southeast of sampling locality and was still in motion during the Cenozoic.     

Geological constraints for tectonic models of the alpha ridge

Initial interpretations of the CESAR geological samples are re-examined in light of new data from the Alpha Ridge and circum-Arctic region. A composite stratigraphy for the CESAR and Fletcher Island (T-3) pre-Neogene cores shows a sequence of Campanian-Maastrichtian organic-rich terrigenous mud overlain by Maastrichtian-Eocene biosiliceous marine deposits with a low organic content, terminating in volcanoclastic mudstone of Late Eocene age. CESAR core 6 contains a transition zone in which biosiliceous sediment is replaced by volcanoclastic and terrigenous sediment of Paleocene-Eocene age. Palynomorphs provide a Late Eocene age for the volcanic outcrop dredged from Northern Alpha Ridge. Textural and geochemical studies of laminated biosiliceous sediments were made with special techniques for quantitative analyses of very small samples (1–10 mg) and particle sizes of less than 5 microns. Results show that the laminated sediments were deposited very slowly in an oxidizing environment. Laminae in CESAR core 6 mainly reflect cyclical variations in the formation and/or accumulation of particulate iron, probably due to periodic hydrothermal venting. Absence of detrital sediment, sparsity of pyroclastic material and lack of diagenetic alteration of the biogenic sediments suggest that the eastern Alpha Ridge was not an area of major tectonic activity during the Eurekan Orogeny, from ca. 80-40 Ma.     

Preliminary results on kinematic model of tectonic blocks derived from high precision GPS observations in Southwest China

ＰｒｅｌｉｍｉｎａｒｙｒｅｓｕｌｔｓｏｎｋｉｎｅｍａｔｉｃｍｏｄｅｌｏｆｔｅｃｔｏｎｉｃｂｌｏｃｋｓｄｅｒｉｖｅｄｆｒｏｍｈｉｇｈｐｒｅｃｉｓｉｏｎＧＰＳｏｂｓｅｒｖａｔｉｏｎｓｉｎＳｏｕｔｈｗｅｓｔＣｈｉｎａＬＩＲＥＮＨＵＡＮＧ１）（黄立人）...