Rodinia裂解与华南微板块形成和演化

介绍了Rodinia研究的历史、现状及主要进展,分析了华南相关地块在Rodinia中的位置以及从Rodinia到Pangea的演化历程.分析结果表明,扬子陆块从Rodinia裂离后,其间在Gondwana形成时,可能发生过湘桂地体、云开地体、浙闽地体、保山地体和腾冲地体的碰撞拼贴造山作用过程.在古特提斯演化阶段,这些地体随古特提斯洋的开启而与扬子陆块裂离,并逐渐形成多岛洋的构造格局,之后又随Pangea的形成而再次与扬子陆块碰撞拼贴增生.因此,Rodinia,Gondwana,Pangea等的形成、裂解和裂离后地体的拼贴增生是认识华南大地构造格局和演化的关键之一.Rodinia应该是华南大地构造研究值得重视的重要课题.     

内蒙古东北部及周边地区前中生代构造发展演化史

内蒙古东北部地处西伯利亚板块南缘,南与中朝板块相邻。元古代—古生代期间历经西伯利亚板块的向南增生、地体拼贴、“中东亚洋”关闭和西伯利亚－中朝板块的对接碰撞形成统一欧亚板块等一系列构造事件,形成规模巨大的兴安－内蒙古地槽褶皱系（大陆边缘造山带）。中新生代主要受欧亚板块和太平洋板块运动的影响,表现为陆内造山作用,形成三种性质不同的叠合盆地。     

华北板块北缘东段古生代沉积特征及盆地演化研究进展

通过对吉林伊通、长春、永吉、桦甸等野外实地考察,结合前人研究成果,总结华北板块与西伯利亚板块碰撞拼贴方式、古亚洲洋南支洋闭合过程以及华北板块北缘沉积特征与盆地演化。研究区地质构造错综复杂,沉积体系保存不全;受中新生代构造的影响,叠加了中新生代构造变形、岩浆活动和成矿作用;地层被破坏,多为哑地层,上述原因导致对古亚洲洋闭合之前盆地的性质及演化认识不一,制约了对有关重要科学问题的深入研究。采用沉积学的方法,结合构造地质学、地球化学、古生物地层学、同位素测年等理论和方法,依据现存古生代地层和不同构造部位的沉积盆地类型及其基本特征,开展古生代构造古地理演化研究,恢复沟弧盆体系的分布以及岛弧的类型、时代,探讨古亚洲洋的闭合过程,将是探讨华北板块北缘东段构造演化特征的新思路。     

华北板块南部高变质煤条带成因机制

 为确定华北板块南缘高变质煤条带形成机制与形成时代,通过研究华北板块南缘中二叠统山西组二1煤层煤级分布和岩浆岩空间展布特征,结合华北板块与扬子板块碰撞历史,利用地质学"重力均衡"原理和日本岩石学家都城秋穗提出的"双变质带"理论,建立碰撞热流模型并合理解释导致高变质煤条带形成的热流来源,得出:1)扬子板块向华北板块的俯冲作用,在华北板块南缘前陆盆地形成高温低压带,促进了煤化作用,形成高变质煤条带;2)结合地质资料和区域构造特征分析,发现高变质煤带走向与印支期构造走向(东-西)一致,该高变质煤条带形成于印支期。燕山期岩浆控制了华北板块南缘大部分煤变质作用,但是在晋城-济源一带其煤变质是由于印支期板块碰撞形成的异常热作用的结果。     

中国地体构造研究进展综述

地体构造理论被应用于中国地质的具体实践已经１５年并取得了丰硕的成果,主要表现在：１．中国境内地体构造的划分,２．地体构造理论上的创新,包括地体定义的完善;板块、微板块、地体、板惩、覆体五者之间的理论甄别,地体的古板块单元重建和古地体古大洋研究;地体拼贴增生和裂解离散的形式和过程,地体运动形成的沉积盆地和能源矿产;３．方法学上的进展,主要有古地磁喾综合地球物理学、微古生物及其对含放射虫硅质岩的新认识     

塔里木盆地与相邻褶被带的区域构造演化

据新地质资料，塔里木盆地和周边褶皱带的区域构造演化可分为四个阶段：（1）前震旦纪：“古新疆克拉通”的形成；（2）震旦纪一中泥盆世：“古南天山洋”的开合和“新疆克拉通板块”的重新拼合；（3）晚泥盆世－三叠纪：“新疆克拉通板块”的局部裂解与拼贴，“新天山洋”的开与合；（4）侏罗纪－第四纪：冈底斯地块北向碰撞，印度板块与欧亚板块碰撞，塔里木盆地及周边区域构造格局最终形成。     

四川攀西拼贴构造

攀枝花－西昌地区位于扬子板块的西南缘。文章运用地体学说，根据断裂、沉积建造、岩浆活动和地球物理等标志的地体解析方法，将其划分为六大地体。并探讨了晋宁期以来，各地体拼合和离散的历史。研究表明该区在地质历史中构造面貌是不断变化的，是一典型的拼贴构造。     

板块运动对松辽盆地构造演化的影响

松辽盆地演化过程中主要受古太平洋板块（〉75Ma）与太平洋板块的影响。根据火山岩年龄分布可以看出松辽盆地演化过程中经过印支、燕山、喜马拉雅山这三个大的构造旋回。在白垩纪以前,根据库拉板块与太平洋板块的俯冲速率及方向变化,结合盆地地层充填特征,认为盆地演化分为六个阶段：基底拼合褶皱期、初始裂陷期、裂陷阶段、坳陷阶段、构造反转阶段、新生代小幅度伸展断陷阶段。     

基于地理学视角的经济板块研究进展

经济板块作为人地关系相互作用的产物,是人地关系地域系统研究的重要内容.文章从产业集群、城市群、主体功能区等方面阐释了地理学视角下经济板块研究的内涵,从经济板块重力、支撑力和摩擦力等作用方式分析了区域经济板块的演变机理.研究认为,经济主体(企业-产业-城市)通过不同的组织与功能塑造了经济板块格局,经济板块基于自身特性在板块的支持力与外界环境的摩擦力作用下不断发展演化.经济板块是自然环境与社会经济耦合作用形成的空间地域实体,基于经济板块研究的不完备性和多学科交叉性、时空尺度的多样性等特点,当前研究应加强国内外对比、创新方法、重视人地关系的相互反馈,不断深化理论、扩展实证研究,以期为协调人地关系、优化人地关系地域系统提供理论指导.     

华北地台金矿成矿规律

根据长其对华北地台金矿的研究,发现一系列有意义的地质地球化学特征并得出许多重要结论,如：１．华北地台是由许多地体拼贴而成,如华熊,嵩箕,鲁西,胶北,胶南和黄海地体等;２．基底地层年代学是确定地体类型的重要基础。Ｏ－型地体是具有太古代绿岩带和早元古绿岩带;Ｃ－型地体祗具有太古代绿岩带,前者有利于金矿的形成;３．中生代华北地台构造环境是岩浆作用和成矿作用的决定因素。这与中生代古太平洋板块和初始欧亚板块     

The spring soil moisture and the summer rainfall in eastern China

The relation between the soil moisture in spring and the rainfall in summer in eastern China is investi- gated. Results show that the summer rainfall in eastern China is closely related to the spring soil moisture in the area from North China to the lower reaches of Yangtze River (NCYR). When spring soil moisture anomalies over NCYR are positive, the summer precipitation exhibits positive anomalies in Northeast China and the lower reaches of Yangtze River, and negative anomalies in southern China and North China. The higher soil moisture over NCYR cools land surface and reduces the land-sea tem- perature gradient, which weakens East Asian summer monsoon. The western Pacific Subtropical High (WPSH) is located to the south and shifts westward, resulting in more rainfall in the lower reaches of Yangtze River and less in southern China and North China.     

下扬子地区盆地的"四层楼"结构及其动力学机制

下扬子地区震旦纪以来经历了不同的大地构造与地球动力学背景 ,盆地演化相应地经历了震旦纪—中三叠世海盆→晚三叠世—中侏罗世沿江前陆盆地→晚侏罗世—早白垩世火山岩盆地→晚白垩世—早第三纪陆相伸展盆地。下扬子地区震旦纪—中三叠世海盆发育于伸展性被动大陆边缘。沿江前陆盆地形成于扬子与华北板块碰撞活动中的前陆变形带上。火山岩盆地出现于区域性走滑剪切和环太平洋岩浆弧背景下。库拉—太平洋板块高角度、高速正面向东亚大陆下的俯冲 ,造成了岩石圈上拱拉张 ,从而产生了晚白垩世—早第三纪的陆相伸展盆地。随着西太平洋边缘弧后盆地的出现及印度与欧亚板块的碰撞 ,中国东部遭受近东西向挤压 ,从而结束了下扬子地区的盆地演化历史。     

Finding of Neoproterozoic （～775 Ma） magmatism recorded in metamorphic complexes from the North Qilian orogen： Evidence from SHRIMP zircon U-Pb dating

The Qilian Mountain is considered a part of the Cen- tral Orogenic Belt of China[1]. The Central Orogenic Belt of China, extending for a distance of about 4000 km long in the E-W direction from the east coast west- ward through the mainland China all the …     

鲁东胶北地区的变形与变质演化史

本文依据在烟台－蓬莱－栖霞地区的详细构造与变质研究，分析胶北地区太古代以来的变形与变质演化历史及其意义．继太古代胶东群形成之后的胶东事件，在胶东群中造成了第一期的南北向构造和同构造麻粒岩相高级区域变质．于粉子山群沉积之后、大致１７亿年前发生的粉子山事件使胶北地区基底最后固结．这期造山事件在基底中产生了广泛的平缓变形面理、褶皱及同构造角闪岩相区域变质．晚石炭世的蓬莱事件，以北北东一南南西向挤压造成了蓬莱群及基底中普遍的北西西－南东东向褶皱及低绿片岩相区域变质．蓬莱事件是华北与扬子板块沿胶南带碰撞的结果．胶北地区的后蓬莱事件造成了局部的北北京向膝折和褶皱，并未伴生区域变质．这一变形事件可能是晚三叠世印支运动或侏罗纪燕山运动的结果．     

Variations in carbon isotopic composition in the subcontinental lithospheric mantle beneath the Yangtze and North China Cratons: Evidence from in-situ analysis of diamonds using SIMS

The components and evolution of subcontinental lithospheric mantle beneath the North China Craton and the Yangtze Craton is a current topic in the geological study of China and the carbon isotopic composition of diamond is one of the most direct probes into cratonic lithospheric mantle processes.In this paper,in-situ SIMS(Secondary Ion Mass Spectrometry) techniques were used to analyze the carbon isotope compositions at different internal growth zones of diamonds from Shandong and Liaoning in the North China Craton and Hunan in the Yangtze Craton.It was found that the carbon isotopic range of diamonds from the North China Craton are rather distinct from those of the Yangtze Craton;the former has a range of 6.0‰ to 2.0‰(relative to VPDB) with an average value of 3.0‰ in their core areas,which is consistent with global peridotitic diamonds;the diamonds from the Yangtze Craton,however,have a carbon isotopic range from 8.6‰ to 3.0‰ with an average value of 7.4‰ in their core areas,being more consistent with global eclogitic diamonds.The variations of carbon isotope ratios between different internal growth zones in individual diamonds were different in the three diamond localities studied.There was a clear correlation between changes in carbon isotopic composition and phases of diamond dissolution and new growth,while no correlation was observed between δ13C and internal inclusions.The variations suggest that the carbon isotopic compositions of mantle fluids were changing during the process of diamond crystallization,and that the heterogeneity of the carbon isotopic composition in mantle carbon reservoirs was a more important factor than carbon isotope fractionation in controlling the carbon isotopic compositions and their variation in diamonds.In addition,the preliminary results of in-situ nitrogen analyses demonstrated that the variation of carbon isotopic compositions between the core and outer growth zones does not correlate with nitrogen abundances,implying either that diamonds crystallized in an open environment or that the carbon isotopic composition and nitrogen contents in mantle fluids were controlled by other,not yet understood factors.The experimental results provide hints that the isotopic composition of carbon and its original sources were different in metasomatic fluids controlling diamond formation in the mantle beneath the North China Craton and the Yangtze Craton.     

辽东青城子矿田煌斑岩锆石U-Pb年龄及其地质意义

为了深入了解辽东青城子矿集区煌斑岩岩石成因、形成的大地构造环境和地质意义,通过单颗粒锆石LA-ICP-MS U-Pb定年系统和X射线荧光光谱仪,对青城子矿集区煌斑岩进行锆石U-Pb年代学和主量元素地球化学方面研究.结果表明,煌斑岩具有低硅、富镁铁的特点,煌斑岩侵位年龄为(226.0±1.0)M a~(227.7±1.3)M a,属于晚三叠世岩浆活动的产物.结合区域构造背景和前人研究,推测煌斑岩是扬子克拉通-华北克拉通深俯冲过程的板片断离的产物,扬子克拉通的深俯冲和陆-陆碰撞可能是华北克拉通东部在中生代破坏的主要原因.     

A possible relict mantle wedge: Geochemical evidence from Paleogene volcanics in North China

The major and trace element and isotopic composition were analyzed for the Paleogene volcanics in North China dated by the K-Ar method. The geochemical data show that most volcanics are in calc-alkaline series and the minor is in alkaline series. They differ obviously from Neogene and Quaternary volcanics in geochemistry. In particular, the Paleogene volcanics from the southern part of North China were derived from enriched lithospheric mantle (EMII), which were likely to be a relict mantle wedge formed during the subduction of the Yangtze plate into the North China plate in late Triassic (Indo-Sinian).     

中国南方大地构造演化及泥盆纪古构造格局

晋宁旋回的若干古老地体经拼合形成原始华南大陆地壳;澄江旋回破裂解体;加里东旋回经多次拉张、挤压后,扬子陆块与华夏陆块拼合形成统一的华南板块;海西—印支旋回在挤压上升背景上平静拉伸张裂,最后发生大陆碰撞;燕山—喜马拉雅旋回发生拉张断陷。泥盆纪古构造格局表现为华南海西期古大陆板块及其南、西缘的被动大陆边缘。可划分出华南陆块、右江-南岭被动陆缘、南秦岭-龙门山-盐瀑、丽江被动陆缘、钦防残留海槽以及它们的次一级构造环境。