藏南康马奥陶系及其底砾岩的发现并初论喜马拉雅沉积盖层与统一变质基底的关系

藏南北喜马拉雅拉轨岗日带康马岩体西南侧，奥陶系及其底砾岩覆盖于前奥陶系拉轨岗日群(POL)之上，后者被515～485Ma拉轨岗日构造穹隆带花岗岩侵入，沿不整合面又被泛非运动最晚期的基性脉岩侵入。奥陶系与前奥陶系的接触关系为伸展不整合，与喜马拉雅甚至冈底斯带有关剖面完全可以对比。这一不整合面即是冈瓦纳大陆北缘统一变质基底和沉积盖层的分界；冈瓦纳大陆统一变质基底的形成始于震旦纪末的“泛非运动”，其终止时间在喜屿拉雅及以北地区可以延续至寒武纪—奥陶纪之交。表现为区域上不断的伸展—拉张—裂解的构造环境。由此可以认为伸展构造亦是控制统一变质基底与沉积盖层的形成机制之一。     

郯庐断裂带早白垩世走滑运动中的构造、岩浆、沉积事件

郯庐断裂带内一系列走滑糜棱岩类的^40Ar/^39Ar测年表明，郯庐断裂早白垩世发生了左旋走滑运动。这一大规模的走滑运动，造成了两类走滑构造，一类为变质岩中低绿片岩相左旋韧性剪切带，另一类为中生代火成岩、沉积岩中的脆性、脆-韧性左行平移断层。这反映断裂带的走滑运动从早白垩世初期持续到早白垩世后期。断裂带的走滑运动诱发大规模的、以富钾、中酸性为主的岩浆活动。地球化学分析显示，这些岩浆岩既有壳源的信息，也有幔源的贡献，反映是断裂减压、壳-幔相互作用下形成的岩浆活动，也暗示断裂带在走滑期切入壳-幔边界。该断裂带走滑运动中，除了在莱阳盆地形成了拉分盆地外，还在合肥盆地东部造成了走滑挠曲盆地，控制下白垩统朱巷组的沉积，郯庐断裂带早白垩世走滑运动中的构造、岩浆、沉积事件，是西太平洋伊泽纳崎板块高速斜向俯冲的结果，属于滨太平洋构造。     

柴达木盆地及其邻区早—中二叠世构造岩相古地理格局

通过大量野外观察、分析测试和综合研究,结合覆盖全区不同比例尺的区域地质调查资料,对柴达木盆地及其邻区早—中二叠世构造岩相古地理格局进行了研究,并探讨了其形成机制。结果表明：柴达木盆地及其邻区中、北部早—中二叠世为陆内盆山裂谷系统,主体处于伸展构造背景,总体表现为堑垒相间的构造古地理格局;南部为巴颜喀拉洋盆,早—中二叠世是巴颜喀拉洋盆扩张最为剧烈且规模最大的时期,巴颜喀拉洋盆中洋岛、海山遍布;早—中二叠世晚期强烈的华力西构造运动使古板块间的相对运动加剧,巴颜喀拉洋盆大洋岩石圈板块向北强烈俯冲,形成东昆仑陆缘岩浆弧及其南部增生带,东昆仑陆缘岩浆弧岩浆活动十分强烈,宗务隆山—西秦岭陆源裂谷盆地进一步发育,形成十分复杂的构造岩相古地理格局。早—中二叠世是研究区地球动力学机制从强烈扩张到强烈汇聚的转折时期,加强其构造岩相古地理研究对建立该区地层序列、探讨其地质演化历史以及指导找矿等均具有重要意义。     

论库姆塔格沙漠羽毛状断裂的成因 ——“八一泉运动”及其与青藏高原隆升、 气候变化的关系

通过野外调查和同位素测年, 讨论了库姆塔格沙漠羽毛状断裂的形成与"八一泉运动"有关, 纠正了前人所说的八一泉雅丹下部褶皱断裂地层属上新世地层的传统概念, 实际上是早更新世湖相地层于中更新世晚期因发生八一泉构造运动形成的褶皱断裂的变形地层带. 所称的上新世地层实际是中更新世晚期的变形地层, 这也是227 ka BP左右的"八一泉运动"的证据, 讨论了它在青藏高原的隆升过程中的特殊阶段, 及其对青藏高原以北地区气候环境的影响, 重新建立了青藏高原隆升与冰期、 间冰期气候变化的序列, 并首次探讨了与中国东部冰缘期的对比问题.     

HORIZONTAL MOVEMENT CHARACTERISTICS OF THE ACTIVE SANWEISHAN FAULT AND ITS MECHANISM: CONSTRAINTS ON THE GROWTH OF THE NORTHERN QINGHAI-TIBETAN PLATEAU

The northern margin of the Qinghai-Tibet Plateau is currently the leading edge of uplift and expansion of the plateau. Over the years, a lot of research has been carried out on the deformation and evolution of the northeastern margin of the Qinghai-Tibet Plateau, and many ideas have been put forward, but there are also many disputes. The Altyn Tagh Fault constitutes the northern boundary of the Qinghai-Tibet Plateau, and there are two active faults on the north side of the Altyn Tagh Fault, named Sanweishan Fault with NEE strike and Nanjieshan Fault with EW strike. Especially, studies on the geometric and kinematic parameters of Sanweishan Fault since the Late Quaternary, which is nearly parallel with the Altyn Tagn Fault, are of great significance for understanding the deformation transfer and distribution in the northwestward extension of the Qinghai-Tibet Plateau. Therefore, interpretation of the fault landforms and statistical analysis of the horizontal displacement on the Sanweishan Fault and its newly discovered western extension are carried out in this paper. We believe that the Sanweishan Fault is an important branch of the eastern section of the Altyn Tagh fault zone. It is located at the front edge of the northwestern Qinghai-Tibet Plateau and is a left-lateral strike-slip and thrust active fault. Based on the interpretation of satellite imagery and microgeomorphology field investigation of Sanweishan main fault and its western segments, it's been found that the Sanweishan main fault constitutes the contact boundary between the Sanweishan Mountain and the alluvial fans. In the bedrock interior and on the north side of the Mogao Grottoes, there are also some branch faults distributed nearly parallel to the main fault. The main fault is about 150km long, striking 65°, mainly dipping SE with dip angles from 50° to 70°. The main fault can be divided into three segments in the spatial geometric distribution:the western segment(Xizhuigou-Dongshuigou, I), which is about 35km long, the middle segment(Dongshuigou-Shigongkouzi, Ⅱ), about 65km long, and the east segment(Shigongkouzi-Shuangta, Ⅲ), about 50km long. The above three segments are arranged in the left or right stepovers. In the west of Mingshashan, it's been found that the fault scarps are distributed near Danghe Reservoir and Yangguan Town in the west of Minshashan Mountain, and we thought those scarps are the westward extension of the main Sanweishan Fault. Along the main fault and its western extension, the different levels of water system(including gullies and rills)and ridges have been offset synchronously, forming a series of fault micro-geomorphology. The scale of the offset water system is proportional to the horizontal displacement. The frequency statistical analysis of the horizontal displacement shows that the displacement has obvious grouping characteristics, which are divided into 6 groups, and the corresponding peaks are 3.4m, 6.7m, 11.4m, 15m, 22m and 26m, respectively. Among them, 3.4m represents the coseismic displacement of the latest ancient earthquake event, and the larger displacement peak represents the accumulation of coseismic displacements of multi-paleoearthquake events. This kind of displacement characterized by approximately equal interval increase indicates that the Sanweishan Fault has experienced multiple characteristic earthquakes since the Late Quaternary and has the possibility of occurrence of earthquakes greater than magnitude 7. The distribution of displacement and structural transformation of the end of the fault indicate that Sanweishan Fault is an "Altyn Tagh Fault"in its infancy. The activities of Sanweishan Fault and its accompanying mountain uplift are the result of the transpression of the northern margin of the Qinghai-Tibet Plateau, representing one of the growth patterns of the northern margin of the plateau.     

东北地区的新构造运动特征分析及新构造运动分区

东北地区包括辽宁，吉林省，黑龙江三省，由于横跨华北和东北两个不同的断块区，东北地区的新构造运动具有显著的区域分异特点，晚第三纪以来，东北地区的构造运动继承了早期构造运动的特点，以断块差异升降运动为主要运动形式。     

昆仑山口西8.1级地震前后地壳垂直运动的负位错模型

利用昆仑山口西8．1级地震震区外围格尔木一五道梁300km长水准测线在1979,1991和2002年3期垂直形变资料,借助研究改进的负位错模型获取发震构造及其相关断裂的运动、变形特征及应力应变积累部位和强度,对与此次大震有关的区域构造形变背景及可能的震后影响进行了研究。结果表明：1991～2002年相对1979～1991年垂直差异运动及应变积累加速增强的特征与昆仑山口西8．1级地震孕育有关;且这样的一个地壳垂直运动加速过程可能还未因地震发生而结束,发震构造相关的断裂构造部位仍有发生较强地震的可能。     

闽西南清流地区加里东期花岗岩锆石U-Pb年代学及Hf同位素组成研究

通过对玮埔岩体两个代表性样品进行锆石的LA-ICP-MSU-Pb测年获得的206Pb/238U加权平均年龄分别为(429.9±3.0)Ma、(446.3±4.0)Ma,证明该岩体确实不是最早认为的印支期花岗岩,而是加里东期岩体。同时对宁化岩体一个样品的锆石LA-ICP-MSU-Pb测年结果得到206Pb/238U加权平均年龄为(448.2±2.5)Ma,同样属于加里东期岩体。进一步对闽西南清流地区玮埔和宁化岩体的锆石Lu-Hf同位素组成分析表明,εHf(t)值主要集中在-0.8～-10.4之间,且Hf二阶段模式年龄(TDM2)集中在1.72～2.34Ga之间,表明其岩浆源区来自华夏地块元古代地壳物质。并结合其他己发表的相关年代学和地球化学资料,可以推断包括玮埔和宁化岩体在内的华南内陆地区加里东期花岗岩很可能是元古宙基底深熔而成的产物;其形成与陆内地壳物质叠置加厚所引起的再造作用关系紧密。     

Precise Dating and Geological Significance of the Caledonian Shangyou Pluton in South Jiangxi Province

The zircon SHRIMP dating age for the Shangyou granites is 464±11 Ma. The geological feature of the pluton is consistent with the isotopic age, which shows that it is a product of Caledonian orogenesis. The Shangyou granites are regarded as peraluminous crust-derived granites to possess the typical geochemical characteristics of calc-alkaline rocks on the active continental margin with enriched Si, K, Al （A/CNK -- 1.11 on average）, HREE, Rb, U, Th and heavily depleted V, Cr, Co, Ni, as well as Ti-Y, Nb-Ta, Zr, Sr, P and Ba, to be commonly corundum normative （av C -- 1.44）. The Shangyou granites with higher 87Sr/86Sr ratios （0.707126-0.712186）, ENd（t） values （-7.29 to -10.22） and （tDM） values （1.52-1.63 Ga）, which are considered to result from partial melting of continental crust metamorphic sedimentary rocks with relatively low of crust maturation degree corresponding to the Middle Proterozoic, to have some possible contributions of mantle-derived components. The Shangyou granites are regarded as post-collision granites, which were formed in a transitional tectonic setting from compression to extension in the Middle Ordovician period after the Yangtze plate was subducted beneath the Cathaysian plate. The Ar-Ar total ages of K-feldspar and biotite are 292.1 Ma and 295.5 Ma respectively, which have recorded information of a late-stage thermal alteration event.     

长期极移的成因

依据宋贯一等(2006)发表的"极移的成因及其移动特征"一文中的研究成果,对其中极移反向(由东向西)运动的时问分布进一步研究得知:在地球公转所处的四季位置中,自转极(北极)反向运动时间仅发生在当年的11月1日(立冬日为11月7、8日)到第二年的2月15日(立春日为2月4、5日)这一段时间之内;其它时间(季节)均为自转极正向(由西向东)运动时段.对比冬至日前后和夏至目前后极移的运动方向可知,它们相对太阳的运动方向虽然相反,由于它们分别处在轨道的东、西方向的两侧,从空间上看来,它们的运动方向却是一致的(即都是向自转极以西运动).基于上述原因,经过一个回归年的太阳光压激发之后,极移运动轨迹的年平均位置向CIO(国际极点)的西侧移动了.在下一个周年期激发时段,上述现象将在上一回归年极移年平均位置的基础上继续进行,逐年累积即形成长期极移.这就是周年期激发机制引起的长期极移及观测的极移运动轨迹均落在CIO西侧的原因.