滇西北新生代逆冲推覆构造

滇西北地区新生代逆冲推覆构造较为发育，从西到东可分出走向NS、相互平行的4带：澜沧江带，云岭带，石钟山带和剑川-洱源带。其中，澜沧江带与云岭带组成对冲格局，云岭带又与石钟山带组成反冲格局，石钟山带与剑川-洱源带又组成对冲格局。参与逆冲推覆的地层主要是中生代三叠系、侏罗系、白垩系及新生代云龙组、宝相寺组，推覆体由石炭系、二叠系、上三叠统岩石组成。逆冲推覆时间为喜马拉雅期。     

阳城横河逆冲推覆构造研究

横河逆冲推覆构造呈北西向挟持于临汾一运城盆地南东边界断裂与新生代同善一承留北西西向断裂间,为两构造带之次级“P”方向剪裂隙。上述两带分别具为右行扭动及左行扭动特征,指示横河逆冲推覆构造带形成于喜马拉雅期。     

南秦岭中新生代逆冲推覆构造事件与金矿的形成

南秦岭中新生代是陆内逆冲推覆褶皱造山和其后的构造伸展的重要时期,前者以形成大型超壳断裂、大型推覆构造、大型紧闭褶皱为特色;后者以形成一系列岩浆岩和大型滑脱构造(张性构造)为主。地质地球物理研究发现秦岭造山带发育一系列由北向南的同碰撞推覆体(张国伟等,1996;许志琴等,1986;袁学诚等,1996)。其中柞水-山阳断裂带     

闽北仁寿地区逆冲推覆构造

逆冲推覆构造发育于闽北变质岩中，由一系列规模不等向南东倾的叠瓦状逆冲推覆断层及其上盘的推覆岩席组成，由南燕向北西方推覆，往逆冲方面可分为上，下2个逆冲推覆构造系，是前展式逆冲推覆构造，作用时期发生于印支期－燕山期。     

论内蒙古大青山地区逆冲推覆构造

大青山逆冲推覆构造发育在石拐断陷盆地南侧,由一系列规模大涉等向南倾的叠瓦状逆冲推覆断层构成,由南南西向北北东方向推覆,是单冲型逆推覆构造。由北向南分为前缘挤压滑构造带、斜歪倒转褶皱逆冲断层带和逆冲推覆岩席及叠瓦状逆冲断层带。     

东昆仑南部晚新生代逆冲推覆构造系统

通过对东大滩—东温泉地区的路线地质观测与构造填图,在东昆仑南部发现晚新生代大型逆冲推覆构造系统。沿低角度逆冲断层,早二叠世大理岩和早三叠世砂板岩自北向南逆冲推覆于古新统—始新统风火山群紫红色砾岩和渐新世砖红色砂砾岩之上,形成大量不同规模的飞来峰;沿主逆冲断层发育厚层断层角砾岩与断层泥,局部形成碳酸盐质糜棱岩。东昆仑南部逆冲推覆构造的发育时代为渐新世晚期—中新世早期,主要形成、活动时期为26～13.5Ma;估算最小逆冲推覆距离为30～35km,最小逆冲推覆运动速率为2.4～2.8mm/a。东昆仑南部晚新生代逆冲推覆构造运动与现今山脉快速隆升存在着动力学成因联系。     

澜沧地区的逆冲推覆构造研究

云南澜沧地区的逆冲推覆构造很发育．可划分为老厂、孟连一澜沧、孟梭及竹塘一澜沧等四个带。推覆构造由推覆体、飞来峰、构造窗、逆冲断层及原地系统等组成，推覆体变形弱、褶皱不发育，符合冲断式推覆模式，具有双重逆冲构造结构．宏观与微观构造都表明形成于较浅的构造层次。推覆构造的形成演化与澜沧裂谷的发展有关，可划分为三期。逆冲推覆的区域应力来自地体向东的碰撞拼接，是印度板块与扬子板块汇聚的重要构造事件。     

藏北改则新生代早期逆冲推覆构造系统

藏北改则及邻区新生代早期发育大型逆冲推覆构造系统,由不同方向的逆冲断层、不同时代的构造岩片、不同规模的飞来峰和构造窗、不同类型的褶皱构造组成.羌塘中部发育羌中薄皮推覆构造,石炭系板岩和二叠系白云质灰岩自北向南逆冲推覆于上白垩统与古近系红层之上,形成大型逆冲岩席和弧形逆冲断层,原地系统古近纪红层下伏三叠系—侏罗系海相烃源岩.羌塘南部发育南羌塘薄皮推覆构造,导致班公—怒江蛇绿岩、三叠系—侏罗系海相地层及侏罗纪混杂岩自北向南逆冲推覆于古近纪红层与下白垩统海相沉积岩层之上,形成三条蛇绿岩片带、大量飞来峰和厚度较大的构造片岩.中新世早期火山岩层和湖相沉积呈角度不整合覆盖逆冲断层、褶皱构造和逆冲岩席,不整合面上覆火山岩年龄为23.7~19.1 Ma,指示中新世早期改则及邻区基本结束了强烈逆冲推覆构造运动.估算羌中逆冲推覆构造的推覆距离约100~115 km,南羌塘逆冲推覆构造的推覆距离约82~110 km;新生代早期改则逆冲推覆构造系统近南北方向逆冲推覆总距离为182~225 km,对应地壳缩短率为(50.3±2.7)%.     

闽西南回龙地区逆冲推覆构造

闽西南回龙地区逆冲推覆发育于桃溪变质核杂岩构造东南缘，由一系列规模不等，倾向南东东的叠瓦状逆冲断层及逆冲岩席组成，推覆运移方向由南东东入北西西，具明显分带，为单冲型逆冲推覆构造，形成发育时期为燕山期。     

藏北新生代火山作用的时空演化与高原隆升

本文通过对藏北新生代火山岩的岩石化学和同位素年龄资料的综合分析,系统确定了火山岩的岩石系列组合及其生成时序。根据岩石系列的时空演化规律将藏北新生代火山活动划分为3个构造—岩浆亚旋回,火山活动自南向北依次形成羌塘(44～24 Ma)、中昆仑—可可西里(19～7 Ma)、西昆仑—玉门(约5 Ma以来)3条火山岩亚带。各岩带分别以高钾钙碱性或钾玄岩系列构成火山活动的主体, 以碱性钾质火山活动而结束。构造—火山旋回与高原脉动隆升具有明显的耦合性,旋回间歇期与高原夷平期相对应。笔者认为这一火山作用规律是高原每次脉动隆升过程中,构造性质由挤压、增厚,向伸展滑移转化的结果,火山作用旋回受岩石圈水平挤压、增厚和深部地幔热物质沿构造薄弱带挤压上升两种作用的相互消长所制约。     

鲁西隆起和济阳坳陷新生代隆坳耦合关系

为探讨鲁西隆起的抬升史,研究鲁西隆起和济阳坳陷之间的隆-坳演化关系,进一步揭示渤海湾盆地的演化特征,主要利用裂变径迹分析和裂变径迹t-T模拟方法建立了新生代鲁西隆起的抬升史和济阳坳陷的沉降史。鲁西隆起三期抬升史分别为62～53Ma、44～37Ma和23～20Ma,济阳坳陷在65～46Ma和46～38Ma期间为快速构造沉降期,构造沉降量大,23Ma左右坳陷抬升。对比研究表明,新生代鲁西隆起的抬升与济阳坳陷沉降之间存在隆-坳耦合关系。鲁西隆起的抬升控制了济阳坳陷烃源岩的形成、油气运移时间和油气分布由南向北迁移,并为济阳坳陷古潜山油藏提供了有效的储集空间。研究还认为,鲁西隆起与济阳坳陷的隆坳耦合关系是渤海湾盆地及周边山系盆山耦合事件的一个组成部分。     

藏北唐古拉山地区沱沱河组孢粉组合及其地层意义

唐古拉山地区广泛出露早新生代陆相红层, 确定这些红层的时代对认识青藏高原的形成具有非常重要的意义.沱沱河组上部的孢粉化石组合以被子植物花粉为主, 且主要为三沟和三孔沟类, 包括栎粉属 (尤其是小栎粉和小亨氏栎粉) 、楝粉属、坡氏粉属和三孔沟粉属等, 具孔类花粉很少, 大部分属种为古近纪常见分子;组合中出现少量鸡爪勒粉属、唇形三沟粉属、山萝卜粉属、管花菊粉属等草本植物花粉;并含有零星古老类型的成分, 如克拉梭粉属、五边粉属和江汉粉属;裸子植物花粉含量低, 蕨类植物孢子零星.基于孢粉组合特征分析, 认为沱沱河组上部的地质时代为始新世中晚期, 为进一步完善了该区新生代地层系统提供了新的依据.      

藏北高原新生代火山岩地球化学系列划分及成因分析

根据K—Ar法和Ar-Ar法定年数据，藏北新生代火山岩从早到晚可划分为多格错仁和走构油茶错高钾钙碱性系列(40—30Ma)、巴毛穷宗和鱼鳞山白榴石碧玄岩—响岩系列(29—24Ma)以及黑石北湖钾玄岩系列(1．5Ma)。从岩石化学和同位素方面对区内新生代火山岩进行了研究，认为藏北新生代火山岩同时具有板内碱性玄武岩和岛弧玄武岩的双重地球化学特征。在成因和源区上各系列存在着差异，高钾钙碱性系列为富集地幔玄武岩底侵作用导致地壳物质部分熔融的产物，并经历了地壳的AF过程。而白榴石碧玄岩—响岩系列和钾玄岩系列来自与古俯冲有关的“古老富集地幔”，为岩浆分离结晶作用的产物。岩浆起源深度随时间变新逐渐变大。     

Cenozoic Vertical-Axis Rotations of the Hoh Xil Basin, Central–Northern Tibet

Understanding the Cenozoic vertical-axis rotation in the Tibetan Plateau is crucial for continental dynamic evolution. Paleomagnetic and rock magnetic investigations were carried out for the Oligocene and Miocene continental rocks of the Hoh Xil basin in order to better understand the tectonic rotations of central Tibet. The study area was located in the Tongtianhe area located in the southern part of the Hoh Xil basin and northern margin of the Tanggula thrust system in central-northern Tibet. A total of 160 independently oriented paleomagnetic samples were drilled from the Tongtianhe section for this study. The magnetic properties of magnetite and hematite have been recognized by measurements of magnetic susceptibility vs. temperature curves and unblocking temperatures. The mean directions of the Oligocene Yaxicuo Group in stratigraphic coordinates(Declination/Inclination = 354.9°/29.3°, k = 33.0, α_(95) = 13.5°, N =5 Sites) and of the Miocene Wudaoliang Group in stratigraphic coordinates(Declination/Inclination = 3.6°/36.4°, k = 161.0, α_(95) = 9.7°, N =3 Sites) pass reversal tests, indicating the primary nature of the characteristic magnetizations. Our results suggested that the sampled areas in the Tuotuohe depression of the Hoh Xil basin have undergone no paleomagnetically detectable rotations under single thrusting from the Tanggula thrust system. Our findings, together with constraints from other tectonic characteristics reported by previous paleomagnetic studies, suggest tectonic rotations in the Cuoredejia and Wudaoliang depressions of the Hoh Xil basin were affected by strike-slip faulting of the Fenghuo Shan-Nangqian thrust systems. A closer examination of geological data and different vertical-axis rotation magnitudes suggest the tectonic history of the Hoh Xil basin may be controlled by thrust and strike-slip faulting since the Eocene.     

新生代酒西盆地沉积特征及其与祁连山隆升关系的研究

酒西盆地普遍缺失上白垩统-始新统,在渐新世晚期开始接受沉积,并形成厚约3．9km的中下第三系一第四系河流相沉积约,不整合覆盖于下白垩统上。渐新统火烧沟组仅在盆地北部出露,往盆地南部尖灭,古流向向南,其物源区应在北部,可能和阿尔金断裂的活动有关。白杨河组全盆均有分布,北祁连山中也有沉积。山中-盆内沉积相由山麓相转变为河湖相,变化明显;古流向大致向北,说明当时祁连山开始隆升,成为白杨河组的物源区。对酒西盆地中、新生界的重矿物进行了系统分析,白杨河组重矿物绝对含量的脉动增加明显,显示白杨河组沉积物源发生变化,原因可能是北祁连山开始隆升,酒西盆地的沉积物源由北转向南侧的祁连山。重矿物的相对含量以及ATi,GZi和ZTR特征值也指示了白杨河组时期矿物成熟度低,构造活动强烈,可能对应着北祁连山的开始隆升。     

Cenozoic stratigraphy of the Sahara,Northern Africa

This paper presents an overview of the Cenozoic stratigraphic record in the Sahara, and shows that the strata display some remarkably similar characteristics across much of the region. In fact, some lithologies of certain ages are exceptionally widespread and persistent, and many of the changes from one lithology to another appear to have been relatively synchronous across the Sahara. The general stratigraphic succession is that of a transition from early Cenozoic carbonate strata to late Cenozoic siliciclastic strata. This transition in lithology coincides with a long-term eustatic fall in sea level since the middle Cretaceous and with a global climate transition from a Late Cretaceous–Early Eocene “warm mode” to a Late Eocene–Quaternary “cool mode”. Much of the shorter-term stratigraphic variability in the Sahara (and even the regional unconformities) also can be correlated with specific changes in sea level, climate, and tectonic activity during the Cenozoic. Specifically, Paleocene and Eocene carbonate strata and phosphate are suggestive of a warm and humid climate, whereas latest Eocene evaporitic strata (and an end-Eocene regional unconformity) are correlated with a eustatic fall in sea level, the build-up of ice in Antarctica, and the appearance of relatively arid climates in the Sahara. The absence of Oligocene strata throughout much of the Sahara is attributed to the effects of generally low eustatic sea level during the Oligocene and tectonic uplift in certain areas during the Late Eocene and Oligocene. Miocene sandstone and conglomerate are attributed to the effects of continued tectonic uplift around the Sahara, generally low eustatic sea level, and enough rainfall to support the development of extensive fluvial systems. Middle–Upper Miocene carbonate strata accumulated in northern Libya in response to a eustatic rise in sea level, whereas Upper Miocene mudstone accumulated along the south side of the Atlas Mountains because uplift of the mountains blocked fluvial access to the Mediterranean Sea. Uppermost Miocene evaporites (and an end-Miocene regional unconformity) in the northern Sahara are correlated with the Messinian desiccation of the Mediterranean Sea. Abundant and widespread Pliocene paleosols are attributed to the onset of relatively arid climate conditions and (or) greater variability of climate conditions, and the appearance of persistent and widespread eolian sediments in the Sahara is coincident with the major glaciation in the northern hemisphere during the Pliocene.     

太行山南缘新生代的隆升与断陷过程

作者通过太行山南缘夷平面、河流阶地、山前盆地和中新生代断裂的调查研究,揭示了太行山南缘新生代的断陷与隆升过程,认为太行山南缘地区新生代以来的构造活动以断裂的断陷、隆升为特征,分为三个相对稳定夷平时期和三个快速隆升阶段,形成三级夷平面.第四纪以来的快速隆升过程可进一步划分为六次相对快速抬升和六个相对稳定堆积时期,形成六级阶地.古近纪断陷活动强烈,第四纪除山前断裂以外,其它断裂未见活动.