东北东部虎林盆地的构造特征、成盆机制及敦-密断裂带北东段的形成时代

虎林盆地位于黑龙江省东部,是叠置在佳木斯地块之上的中、新生代断陷-坳陷盆地,其构造变形可以划分为3个构造演化阶段：早白垩世为NW-SE向伸展作用阶段,主要形成一系列各自独立的NE向箕状断陷群;晚白垩世为NW-SE向挤压作用阶段,使部分早期控陷正断层发生反转,形成反转构造,虎林盆地转化为具有多个沉降中心的NE向挤压坳陷盆地群;古近纪-第四纪为NNW-SSE向挤压作用阶段,虎林盆地的构造格局发生了重大变化,不仅使部分早期控陷正断层发生反转作用形成大型反转构造,而且在七虎林河凹陷与中央隆起之间形成NEE向大型逆冲断层（敦-密断裂）和断层传播褶皱,它们共同控制了盆地的形成和沉积作用,虎林盆地转化为具有1个中央隆起和南、北2个坳陷的NEE向挤压坳陷型盆地。东北地区自白垩纪以来始终处于活动大陆边缘的大地构造背景,包括虎林盆地在内的东北东部盆地群的形成与伊泽纳奇板块、太平洋板块向欧亚板块的俯冲作用有关。敦-密断裂带总体上呈NE向展布,具有左行走滑的性质,在靠近虎林盆地的北东段转变为NEE向展布,断层的性质也转变为逆冲断层,敦-密断裂带北东段的逆冲作用很可能与该断裂带的NE向左行走滑作用在NEE向的转换挤压有关。敦-密断裂带自古近纪始新世-渐新世虎林期开始活动,一直持续活动到第四纪。     

大杨树盆地的构造特征及变形期次

大杨树盆地是叠置于大兴安岭造山带的东部,与松辽盆地紧邻,呈北北东向长条带状展布的中新生代断陷-坳陷型盆地。大杨树盆地经历了多期变形作用,具有以伸展构造为主、并被挤压构造和反转构造叠加的构造特征。早白垩世龙江期主要受到了NWW—SEE向的拉伸作用,形成一系列北北东向控陷犁式正断层组合,在控陷断层的上盘发育小型箕状断陷;早白垩世九峰山期,大杨树盆地受挤压作用控制,使早期形成的断陷盆地发生反转作用,形成正反转构造,同时在某些地段形成逆冲断层和断层传播褶皱;早白垩世甘河期,大杨树盆地再次受到伸展作用,形成了一系列北北东向小型断陷。早白垩世晚期(甘河期之后)—晚白垩世早期,大杨树盆地受到强烈的挤压作用,使早期控陷正断层出现正反转作用,在盆地的浅部形成大型断层传播褶皱,使大杨树盆地全面隆升遭受剥蚀。第四纪大杨树盆地具有伸展的特征,发育一系列小型伸展断陷。     

湖南涟邵煤田梅城-寒婆坳地区控煤构造分带特征

梅城-寒婆坳地区位于湖南省涟邵煤田北段西部,受多期构造运动影响,区内广泛发育紧密线状褶皱和一系列由南东往北西挤压形成的逆冲断层。依据野外观测及地质资料分析了研究区构造几何形态,提出该区构造具有分带分段的特征,自北向南划分为北、中、南三个构造区带,自西向东分为西、中、东三个带。北段主体构造线方向为NE向,构造样式以叠瓦状逆冲断层为主;中段主体断层走向由NNE转为近SN向,以褶皱为主,推覆断裂为辅,局部发育白垩系红层;南段构造转为SN向,为一东翼被破坏的向斜。     

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,由一系列规模大小不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,是单冲型逆冲推覆构造。由北向南分为前缘挤压滑脱构造带、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。     

塔西南坳陷甫沙构造带正反转构造及其石油地质意义

塔西南坳陷甫沙构造带褶皱冲断强烈,古近系膏泥岩下层构造变形复杂,具有正反转构造变形特征。侏罗纪—白垩纪区域伸展环境发育大量正断层,后期在喜马拉雅运动中受挤压反转。南部发育高角度基底卷入正反转断层,中部发育叠瓦式逆冲断层,北部边缘变形微弱。相应地将甫沙构造带划分为反转断隆背斜带、楔状叠瓦构造带和逆冲前缘构造带;反转程度南强北弱、西强东弱。对区域构造变形环境的分析表明,西昆仑山隆升引发水平挤压叠加垂直向上的剪切作用,使先存高角度正断层容易被迁就利用进而发生正反转。对正反转相关构造圈闭评价认为:反转断隆背斜带发育的圈闭规模大,幅度低,埋藏浅,落实程度高,但上覆膏泥岩层薄,被断层破坏强烈,油气散失严重;楔状叠瓦构造带发育的圈闭规模小,幅度大,埋藏深,落实程度低,上覆膏泥岩层厚,有利于油气保存;逆冲前缘构造带发育低幅度隆起和地层岩性圈闭。     

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。     

松辽盆地伏龙泉断陷构造特征及演化

伏龙泉断陷是松辽盆地一级构造单元东南部隆起之上的二级构造单元,构造特征比较复杂。地震剖面解释表明,伏龙泉断陷自白垩纪以来主要经历了4个构造演化阶段:在火石岭组营城组下部沉积时期为近EW向伸展作用阶段,形成以大型犁式正断层为控陷断层的近NS向箕状半地堑和滚动背斜;在营城组上部泉头组中段沉积时期为近EW向挤压作用阶段,使早期控陷正断层发生反转作用而转化为逆断层,靠近控陷断层的西部边界由于断层上盘的逆冲而隆升,在凹陷中部形成NS向断层传播褶皱,在控陷断层下盘形成双重构造;在泉头组上段嫩江组沉积时期为近NS向离散型走滑作用阶段,形成具有倾向滑移分量的走滑断层组合和负花状构造;在四方台组新生界下部沉积时期为近EW向挤压作用阶段,使在早期控陷断层再次表现为上盘逆冲的特征,在断层上盘形成一大型反转背斜。松辽盆地伸展、挤压、走滑应力场的变化可能与太平洋板块的俯冲角度、方向和速率的变化有关。     

中国含油气盆地的反转构造样式及其油气聚集

反转构造主要指伸展盆地中地堑、半地堑系统遭受挤压变形所产生的压缩构造。它一般经历拉张断陷、稳定坳陷及挤压反转三个演化阶段,构造反转形成的各种褶皱背斜构造直接叠覆在生油断陷之上,生运储配置关系得天独厚,有利于油气聚集。对我国油气勘探反转构造进行成因分类,归纳出断层型、走滑型、热力型及重力型四大类,每一类又可识别出若干种。如断层型反转褶皱,根据张性断层与压性断层的相互叠加关系,可以识别出六种:断层扩展反转褶皱,断层弯曲反转褶皱,断层滑脱反转褶皱,截断型反转褶皱,滑脱逆掩断坡型反转构造,褶皱型反转构造。其中又以断层扩展、断层弯曲、滑脱逆掩断坡和褶皱型等反转构造的含油气性最好。     

周口坳陷叶鲁断裂带构造特征及其演化

叶鲁断裂带位于华北克拉通南部,是鲁山-舞阳-阜阳-淮南断裂带的重要组成部分,控制着周口坳陷谭庄、舞阳等凹陷的形成与演化。据钻井、地震剖面解释和平衡剖面分析,在秦岭-大别造山带挤压活动的影响下,叶鲁断裂带在晚侏罗世—早白垩世向NNE方向强烈逆冲,主断层面倾角约37°,伸展率可达-22 m/Ma;晚白垩世—古近纪,周口坳陷处于伸展构造环境,该断裂带发生负反转构造作用。通过三角剪切软件模拟了叶鲁断裂带主断层在周参12井区的构造演化过程。模拟显示主断层形成时的总滑动量约为6 100 m,断层传播量为9 150 m,三角剪切角为150°,p/s值为1.5。     

松辽盆地南缘十屋断陷构造物理模拟研究

松辽盆地十屋断陷早期伸展阶段形成断陷和坳陷沉积,晚期挤压阶段发生盆地反转。采用铲形和直线形2种边界断层模拟十屋断陷的形成和演化过程。模拟实验结果表明,较陡的主干断层控制的半地堑断陷在侧向挤压过程中发生盆地反转,但是早期形成的正断层不一定发育成为反转断层,而是正断层的倾角变陡,并导致在断陷内的上部盖层中发育形成新的逆断层。这一实验结果较好地解释了松辽盆地十屋断陷的构造演化特征,即断陷期形成的正断层在后期反转构造中受到挤压时发生产状变化并在拗陷期沉积盖层中发育逆断层     

Geohistory analysis and basin development of the Neogene succession, NE Iraq

The Neogene succession in the studied area is represented by seven formations (Serikagni, Euphrates, Dhiban, Jeribe, Fatha, Injana, and Muqdadiya formations). The area of study is located in the Unstable Shelf within the Low Folded Zone and the north part of the Stable Shelf (Mesopotamian Zone). This study included the geohistory analysis of the Neogene succession and interpretation the changes of the accumulation and subsidence rates and compared them with the space available to explanation the basin development. At The Early Miocene (Aquitanian age), the Sirekagni and Euphrates formations was deposited during a major transgression with high rates of subsidence and accumulation in the Himreen, Makhul, and north of Tigris subzones, while the Chemchemal–Arbil and Butmah–Mosul subzones were positive areas. This period ended with a sea withdrawal to the southeast to generate the Dhiban lagoonal basin which was characterized by low accumulation and subsidence rates. During the Early Burdigalian, the Jeribe Formation was deposited during another sea level rise that covered the area except the Chemchemal–Arbil and Butmah–Mosul subzones representing the uplifted positive area. The sea level rise continued to the early Langhian age where the transition beds for the Fatha Formation was deposited to mark the maximum flooding surface covering all the study area. The Fatha Formation was deposited at the Late Langhian to the Early Serravallian during sea level stillstand with high accumulation and subsidence rates in the Himreen subzone and the Chemchemal–Arbil subzone. This period ended without a clear tectonic activity. The period from Late Miocene to Pliocene was characterized by high tectonic activity and sea level fall where fluvial–lacustrine environment prevailed to deposit the Injana and Muqdadiya formations. The Injana Formation was deposited during the Late Serravallian–Tortonian in the Himreen and Chemchemal–Butmah subzones; in addition to the northern part of Tigris subzone. The areas of high rates of accumulation and subsidence were located near Jambour while the southwestern part was affected by an uplift generating the Himreen structure. The Chemchemal–Butmah subzones was characterized by a high uplift in the southeast part where Kirkuk and Chemchemal structures were forming, while The northeastern part (from Bi Hassan to the borehole Kirkuk-117) was with low accumulation and subsidence rates. The linear region between these parts (Khabaz oil field) showed an abnormal values for accumulation and subsidence rates (very high); this region corresponds to the location and direction of Anah–Fatha–Qalat Dizah Fault which suggest that the fault was active during that time. The tectonic activity continued to uplift all the north of the study area as well as the West and the East during the Late Tortonian to the Piacenzian where the Muqdadiya Formation was deposited in the area between Jambour to Khabaz oilfields. Then the succession was deformed and uplifted to approximately 800 m above the sea level as in the present day.     

东秦岭北部富碱侵入岩岩石化学与分布特征

在东秦岭北部，富碱侵入岩的侵位与空间分布受同一个区域构造带（华并陆块南缘）控制，构成一个区域性的富碱岩浆岩带。根据岩石学和岩石化学研究，岩石类型主要分为三大类：（1）碱性岩类，即含有似长石或碱性暗色矿物的正长岩类；（2）碱性花岗岩类，包括钠铁闪石花岗岩及孪生的钾长花岗岩类；（3）石英正长岩类，包括碱性长石为主的石英正长岩、英碱正长岩和花岗正长（斑）岩类。根据富碱岩浆岩带的岩石化学特征，自北而南可以划分为三个亚带：北部碱性岩亚带，以SiO2饱和而l2O3不饱和出现碱性暗色矿物为特征；中部碱性花岗岩亚带，以SiO2强饱和而Al2O3不饱和出现碱性暗色矿物和大量石英为特征；南部石英正长岩亚带，以SiO2和Al2O3都饱和但CaO强烈亏损，缺乏Ca质斜长石，出现碱性长石占长石总量的绝对优势（一般＞95％）为特征。三个亚带富碱岩浆在化学成分方面虽有差异，但共同具有富碱高钾钙征，ALK＝10－15，K2O含量范围5％－15％，K2O／Na2O＝1．26－8．30。     

对苏皖断裂带的初步研究(郯—庐断裂研究之二)

苏皖断裂带是郯庐断裂的南段,即在江苏和皖北地区部分的区域名称。和山东的沂沭断裂带一样,由东、西两个断裂亚带(束)组成。本文通过对苏皖新裂带地质构造基本特征的研究和整理,纠正了过去不尽合理的连法,特别是南部近巢湖一带东、西界断裂的连法;本文还比较系统地分析了苏皖断裂带的发生、发展历史,并对苏皖断裂带的构造归宿进行了初步探讨。笔者认为:苏皖断裂带应属经向构造带。它的总体走向为近南北—北北东,倾角较陡。是一条很有意义的成岩成矿物质来源的通道。关于苏皖断裂带成为分割新华夏构造系在江苏和皖北境内第二隆起带和第二沉降带的分野断裂带,也即是说,中生代以来苏皖断裂带是新华夏构造系的一个重要组成部分的看法,笔者认为,中生代中、晚期以来,新华夏构造系利用、改造并归并经向构造带的苏皖断裂带成为它的一个重要组成成分,即苏皖断裂带的构造归宿具有一仆二主的性质。     

郯庐断裂带晚中生代演化历史及其对华北克拉通破坏过程的指示

郯庐断裂带晚中生代的演化历史是华北克拉通破坏过程的重要记录。中侏罗世末(燕山运动A幕),郯庐断裂带局部发生左行平移活动,而华北克拉通上出现了一系列北北东走向的缩短构造,指示了西太平洋伊泽奈崎板块俯冲的开始。晚侏罗世期间,郯庐断裂带没有发生活动,而华北克拉通出现局部伸展与岩浆活动及区域性隆升,应为弧后弱拉张背景。早白垩世初(燕山运动B幕),郯庐断裂带再次发生强烈的左行平移活动,华北克拉通北部与东部出现了一系列近南北向挤压产生的构造,应是鄂霍茨克洋最终关闭与伊泽奈崎板块高速俯冲双重作用的结果。随后的早白垩世期间,华北克拉通在弧后拉张背景下发生峰期破坏,郯庐断裂带呈现为强烈的伸展活动。早白垩世末的区域性挤压作用,结束了华北克拉通的峰期破坏,并使郯庐断裂带再次发生了一期左行平移活动。这期挤压作用出现在太平洋板块接替伊泽奈崎板块这一重大板块调整的背景之中。     

班公湖-怒江结合带西段多岛弧盆系时空结构初步分析

笔者依据班公湖地区1：25万喀纳幅、日土县幅、羌多幅地质填图和专题研究工作取得的阶段性成果,将班公湖带的多岛弧盆系时空结构厘定为3条蛇绿混杂岩亚带。该3条亚带为盆地所隔,从北而南依次为班公湖带北亚带、班摩掌侏罗纪弧间盆地、班公湖带中亚带、日土-巴尔穷侏罗纪—早白垩世复合弧后盆地和班公湖带南亚带等。初步认为班公湖-怒江特提斯洋经历了晚三叠—早侏罗世往北俯冲、中晚侏罗世早期向北、往南双向俯冲、早白垩世往南俯冲等3次俯冲消亡阶段;同时,讨论了在班公湖带研究中存在的问题及其在反演班公湖-怒江结合带西段构造演化和在找矿方面的意义,以及进一步研究方向。     

红河断裂带两侧地震震源机制及构造意义

红河断裂带是一条大型的走滑断裂带。根据印支半岛前新生代的古地块与华南地块的接触关系 ,将红河断裂带海陆部分分为两段。断裂带自第三纪以来 ,经历了左旋运动、右旋运动 ,南北两段的活动性有一定的差异。根据断裂带两侧地震和震源机制解分析 ,震源深度 0～ 33km的地震在整个区域密集分布 ,较深的地震分布在断裂的北东侧。断裂带西北部断裂活动方式为逆冲型 ,北部为正断型 ,南部为走滑型 ,其它地方为奇异型 ,也即是逆冲型、正断型、走滑型 3种方式的过渡类型 ,反映了红河断裂带及其周围地区受到来自北北西向的推挤力和北东东向的正压力的联合作用 ,使受力区的断裂发生挤压逆冲、水平走滑和拉张正断运动。     

The Elbe Fault System in North Central Europe—a basement controlled zone of crustal weakness

The Elbe Fault System (EFS) is a WNW-striking zone extending from the southeastern North Sea to southwestern Poland along the present southern margin of the North German Basin and the northern margin of the Sudetes Mountains. Although details are still under debate, geological and geophysical data reveal that upper crustal deformation along the Elbe Fault System has taken place repeatedly since Late Carboniferous times with changing kinematic activity in response to variation in the stress regime. In Late Carboniferous to early Permian times, the Elbe Fault System was part of a post-Variscan wrench fault system and acted as the southern boundary fault during the formation of the Permian Basins along the Trans-European Suture Zone (sensu [Geol. Mag. 134 (5) (1997) 585]). The Teisseyre–Tornquist Zone (TTZ) most probably provided the northern counterpart in a pull-apart scenario at that time. Further strain localisation took place during late Mesozoic transtension, when local shear within the Elbe Fault System caused subsidence and basin formation along and parallel to the fault system. The most intense deformation took place along the system during late Cretaceous–early Cenozoic time, when the Elbe Fault System responded to regional compression with up to 4 km of uplift and formation of internal flexural highs. Compressional deformation continued during early Cenozoic time and actually may be ongoing. The upper crust of the Elbe Fault System, which itself reacted in a more or less ductile fashion, is underlain by a lower crust characterised by low P-wave velocities, low densities and a weak rheology. Structural, seismic and gravimetric data as well as rheology models support the assumption that a weak, stress-sensitive zone in the lower crust is the reason for the high mobility of the area and repeated strain localisation along the Elbe Fault System.     

南海北缘钻探选址：滨海断裂带大型海洋地质灾害研究

滨海断裂带是南海北缘的一条大型活动断裂带，其位置靠近我国华南沿海地区。滨海断裂带全长超过1200 km，包括西段（北部湾- 阳江），中段（珠江口）和东段（粤东- 福建）。其西段和东段历史上至少曾发生过4次大地震（M7+），中段目前是一个大地震空区。在经济高速发展和人口高度密集的今天，如果滨海断裂带再次发生大地震并触发海啸，必将对我国华南沿海地区造成灾难性破坏。由于缺乏完整的历史地震记录和针对古地震的钻孔沉积研究，目前尚不清楚滨海断裂带大地震的准确次数、空间分布和复发周期，以及中段大地震空区的主要原因（断层蠕滑或大地震周期较长），因此无法有效评估该断裂带的大地震破裂分段和灾害风险。本研究总结了滨海断裂带的构造特征、重点描述了3次历史大地震及引发的灾害影响，和国际上针对海底大地震的钻探研究经验。根据这些信息，本文建议在断裂带的西段、中断和东段进行大洋钻探，获取穿过断层带的关键沉积和岩石样品，利用沉积古地震方法重建滨海断裂带东段和西段的大地震历史和复发周期，研究断层带的岩石物理性质，揭示滨海断裂中段大地震空区的成因，解析断层分段式破裂的原因，为我国海洋防灾减灾提供重要的科学依据。     

EARTHQUAKE FOCAL MECHANISM AND ITS TECTONIC SIGNIFICANCE ALONG THE TWO SIDES OF THE RED RIVER FAULT ZONE

The Red River Fault Zone is a gigantic slide-slip fault zone extending up to 1000km from Tibet to South China Sea. It has been divided into the north, central and south segments according to the difference of the geometry, kinetics, and seismicity on the land, but according to the contacted relationship between the old pre-Cenozoic block in Indochina Peninsula and the South China block, the Red River Fault Zone was divided into two parts extending from land to ocean, the north and south segments. Since the Tertiary, the Red River Fault Zone suffered first the sinistral movement and then the dextral movement. The activities of the north and the south segments were different. Based on the analysis of earthquakes and focal mechanism solutions, earthquakes with the focus depths of 0-33km are distributed over the whole region and more deep earthquakes are distributed on the northeastern sides of the Red River fault. Types of faulting activities are the thrust in the northwest, the normal in the north and the     

莺歌海盆地构造转折界面的确定及其地质意义

中国西南部红河断裂带的活动演化历史长期以来备受国内外学者的关注,该断裂从陆地向海域延伸进入莺歌海盆地,并对莺歌海盆地的形成和演化起重要的控制作用。目前,红河断裂带经历早期的左旋走滑运动和后期的右旋走滑运动已经得到公认,但对于其精细的构造演化历史及其左旋走滑向右旋走滑运动转换的时间还未能达成共识。本文利用构造控制沉积、沉积反映构造的思想,通过对莺歌海盆地三维地震资料的构造解析,从T27界面上下地层厚度存在"跷跷板"式的变化、沉积中心的迁移、沉积速率的变化、陆架-陆坡坡折带的出现、微小断裂的特征以及底辟构造等方面的研究,确定莺歌海盆地红河断裂带的左旋走滑运动停止于T40(10.5Ma);T40~T30(10.5~5.5Ma)是构造变形的平静期;T30~T27(5.5~2.4 Ma)为左旋走滑运动向右旋走滑运动转换时期;T27(2.4 Ma)以后右旋走滑活动开始,并控制坡折带(包括莺歌海盆地和琼东南盆地)和底辟构造等的形成;T20(1.9 Ma)以来,右旋走滑活动逐渐减弱。