维西‒乔后断裂通甸‒马登盆地段晚第四纪活动特征

依据野外调查成果, 研究维西?乔后断裂通甸?马登盆地段晚第四纪活动的地质地貌特征和古地震事件。结果表明, 该断裂段属于全新世活动段, 以右旋走滑运动为主, 全新世以来的水平滑动速率为1.8~2.4 mm/a, 垂直滑动速率为0.30~0.35 mm/a。 玉水坪探槽 揭示的断错地层OSL年龄为5.1±0.6, 5.3±0.2, 7.5±0.5和10.3±0.9 ka, 属于全新世堆积。下太平某小河T₂阶地上发育的多条断层断错现代土壤层之下的所有地层, 被错上部地层的OSL年龄为5.3±0.6 ka。上新世以来的断裂活动造成上新统的强烈构造变形, 其运动性质由逆冲转变为右旋走滑。新民村和盖场等探槽揭露地震楔、砂脉和软沉积构造变形等地震现象, 垂直错距多在1 m左右, 属同一期地震事件所为, 其发生时间约为28000 aBP, 震级达到7级。     

西藏喀喇昆仑断裂东南段晚第四纪活动的地质地貌特征

为了分析西藏喀喇昆仑断裂东段段第四纪活动地质地貌特征,通过对该段进行遥感影像、野外地质地貌调查、断错地貌测量等方法和手段,获得了该断裂晚第四纪活动的地质地貌特征。在扎西岗北东河流阶地中发现断裂切割全新世的阶地堆积物。同时,对断裂不同的地段进行断错测量,获得了定量的断层数据,反映了断层活动的幅度及期次。研究结果表明,该断裂东南段晚第四纪以来右旋走滑量介于2～220 m,具有多期次活动特征,活动方式以右旋走滑为主,兼具正断分量。     

青藏高原嘉黎断裂晚第四纪运动特征

通过野外考察与GPS观测数据的综合分析, 对嘉黎断裂晚第四纪运动特征得到一些新的认识。嘉黎断裂不是整体右旋走滑断层, 其不同构造部位的运动性质和速率具有分段差异特征。以东构造结为界大致分为3段: 东构造结以西为嘉黎断裂西北段, 东构造结顶端易贡?通麦段为嘉黎断裂中段, 东构造结东南部分为嘉黎断裂的东南段。西北段为右旋挤压运动, 走滑速率3.2~5.8 mm/a; 中段弱右旋挤压运动, 走滑速率1.3~2.0 mm/a; 东南段为左旋挤压运动, 走滑速率3.7~4.0 mm/a。     

青藏高原东缘安宁河断裂带中-新生代构造变形及其磁组构特征

安宁河断裂带是青藏高原东缘大型走滑断裂系鲜水河-小江断裂系重要组成部分,演化历史悠久,构造变形复杂。为了进一步理清青藏高原东缘安宁河断裂带中-新生代构造变形,文中通过详细的野外构造观察与解析并结合构造岩磁组构对安宁河断裂带进行精细的构造变形研究,厘定了安宁河断裂中-新生代构造变形序列及其变形特征。结果表明中生代安宁河断裂带先后经历了印支晚期NEE-SWW向挤压作用下的早期具有左行走滑特征的韧性剪切和晚期韧-脆性密集劈理化构造变形过程以及晚中生代近E-W向挤压作用下形成的低角度韧-脆性剪切三期构造变形过程;构造岩磁组构样品的平均磁化率具有强、弱磁化率2种特征,且构造岩具有磁面理较磁线理发育的特征,磁化率椭球体以压扁型为主,构造强应变特征明显;最小磁化率主轴呈NEE-SWW向,即中生代早期的韧脆性变形受到了NEE-SWW向的挤压作用,但运动学分析结果反映出了后期叠加改造的特征。新生代安宁河断裂带整体经历了NWW-SEE向挤压作用下以左行走滑为主的具有自西向东扩展特征的三幕挤压走滑和两幕斜张走滑构造变形过程,奠定了安宁河断裂带现今两堑夹一垒的构造地貌。这为深入认识和恢复川滇南北构造带及其青藏高原东缘的形成演化过程奠定了基础。     

香山北缘活动断裂带几何结构特征及其分段性分析

香山北缘活动断裂带是一条以左旋走滑为主,兼具倾向滑动的全新世活动断裂带,由9个不连续的次级断层组成。在野外实测工作基础上,对该断裂带的几何结构特征及其分段性进行讨论,以一碗泉间断点为界将香山北缘活动断裂带划分为东、西两个分段。     

阿尔金山走滑断裂构造样式

该文认为,阿尔金山走滑断裂构造是一巨型左行左列走滑断裂兼逆冲推覆和韧性剪切性质的断裂构造带。走滑断裂带叠覆区发育拉分盆地。走滑断裂带旁侧拉张区形成火山岩带、拉张盆地及相应的弧形构造;挤压区形成弧形构造及相应的挤压-拉张盆地。中新生代以来,走滑断裂带最大水平位移量为550km。     

沂沭断裂带北段大盛-马站早白垩世盆地成因分析

为了分析大盛 -马站盆地的成因类型 ,重点调查了盆地内沉积相带的空间展布特征及盆地沉积中心迁移的规律 .盆地内同生构造显示盆地边缘主干断裂具有左行走滑特点 .盆地内生物化石及火山岩年代学特征表明盆地形成于早白垩世 .盆地性质为左旋走滑拉分盆地 ,说明郯庐断裂在早白垩世晚期发生过左旋走滑活动     

阿尔金断裂走滑运动对柴达木盆地的侧向效应

阿尔金断裂因其巨大的规模及走滑量而被许多学者认为具有显著的侧向效应,并将柴达木盆地西北部反S型褶皱-冲断带的形成机制归结于此,然而这种推测的观点缺乏有力依据.构造物理模拟是研究构造变形机制的有效方法,笔者通过3组三维模型研究阿尔金断裂走滑运动对柴达木盆地构造变形影响的范围和方式,其结果表明:①不论阿尔金断裂平移走滑还是挤压型走滑,都对柴达木盆地产生挤压作用,但挤压应力作用范围及地体运动速率有差异:平移走滑影响范围的前缘边界为弧形,地体运动速率递减较慢,而挤压型走滑的前缘边界为直线形,地体运动速率快速减小;②柴达木盆地近南北向挤压收缩强度远大于阿尔金断裂左行走滑引起的变形,使得紧邻断裂的地体因走滑牵引而发生的运动方向被盆地近南北向的收缩变形所改变;③阿尔金断裂左行走滑对柴达木盆地构造变形的影响集中于盆地西南部,与反S型褶皱-冲断带发育位置不符,不支持反S型褶皱-冲断带的形成受阿尔金断裂控制的观点.     

徐深气田断裂发育及其对天然气成藏的控制作用

为准确判断松辽盆地徐深气田断裂的发育及其与深层天然气成藏之间的关系,根据钻井、测井和分析测试资料,利用断裂生长指数、断裂活动速率、剖面伸展率及构造演化剖面,厘定徐深气田断裂主要活动时期、断裂系统等,并建立该区的天然气成藏模式。结果表明:徐深气田断裂主要活动时期由古至今依次为火石岭组、沙河子组、营一段、营三段、泉头组末—姚家组沉积时期;气田内断裂可划分为早期伸展断裂系统(Ⅰ)、早期走滑伸展断裂系统(Ⅱ)、晚期伸展断裂系统(Ⅲ)、晚期张扭断裂系统(Ⅳ)、早期走滑伸展—晚期伸展断裂系统(Ⅴ)、早期走滑伸展—晚期张扭断裂系统(Ⅵ)、走滑断裂系统(Ⅶ)(徐中、徐东)。Ⅴ、Ⅵ、Ⅶ型断裂系统是构成气源断裂的主要断裂系统类型。工业气流井均分布在距源断裂3 km范围内的火山岩区域内。     

江南断裂带(皖南段)的变形特征及震旦纪以来的构造演化

主要对发育在皖南段的江南断裂带变形特征进行了讨论。并以“开”“合”机制为基本思想，对江南断裂带自震旦纪以来的构造演化史进行了分析，确定了该断裂活动从伸展（同生断层）—逆冲推覆—伸展（断陷）—逆冲（走滑）这一演化序列。     

阿尔金断裂带东端断裂展布型式的研究

利用高精度的ETM卫星图像,从宏观和露头尺度对阿尔金断裂带过祁连山后的酒西盆地-宽滩山地区的断裂展布形式和特征进行了详细的地质解译和实地考察,发现除主干断层以外还有4条具有一定规模的均具左旋位错特征的分支断层,且呈"树枝状"展布。通过研究得出,阿尔金断裂带以"树枝状"的型式消失在酒西盆地和花海盆地内。     

阿尔金断裂带东端断裂展布型式的研究

利用高精度的ETM卫星图像,从宏观和露头尺度对阿尔金断裂带过祁连山后的酒西盆地-宽滩山地区的断裂展布形式和特征进行了详细的地质解译和实地考察,发现除主干断层以外还有4条具有一定规模的均具左旋位错特征的分支断层,且呈“树枝状”展布。通过研究得出,阿尔金断裂带以“树枝状”的型式消失在酒西盆地和花海盆地内。     

南阳凹陷边界断层三维几何学及运动学特征

新野断层位于南襄盆地南阳凹陷南部的控凹边界断裂,研究其三维几何学和运动学特征对分析南阳凹陷的形成演化至关重要。以2/3D地震、钻井及测井资料为基础,以正断层相关褶皱理论和构造复原理论为指导,深入剖析新野断层的三维几何学和运动学特征及其对凹陷形成的控制作用。根据断层平面走向,结合倾角和断距变化,将新野断层分为西、中、东3段;空间上认为,新野断层是由多个等倾角面构成的复杂曲面,通过两个垂向轴面和4个横向轴面,将新野断层断面分为11个等倾角区。根据平衡地质剖面复原结果对比,认为新野断层西段、东段形成于晚白垩世,中段形成于始新世大仓房期并逐渐与西段、东段硬连接形成一条断层;断层及其上盘地层旋转程度自西向东逐渐增强;断层反转强度自西向东亦逐渐变大。新野断层西段为"座椅式"正断层,中段由"转折式"正断层转"犁式"正断层,东段为"犁式"正断层。沿断层走向的差异沉降和断面形态差异是南阳凹陷构造特征及形成演化的重要控制因素。     

阿尔金断裂的研究现状及其控油意义

阿尔金断裂是中国西北一条巨型的NEE断裂构造,也是青藏高原的西北边界,它在青藏高原的隆升及中国大陆动力学演化方面有着及其重要的地位,一直成为国内外地学界研究的热点.断裂活动的时间、方式、速度及规模等是阿尔金断裂问题争论的焦点.针对目前国内外研究现状,结合柴达木盆地一些实际资料,认为阿尔金断裂带的活动具有多期次性,而至少在中新世时期开始阿尔金总体呈左行走滑的趋势;阿尔金断裂带对柴达木盆地与塔里木盆地的沉积构造演化起着重要的作用,从而对西部大陆构造格架及两侧盆地油气运聚具有重要的控制意义.     

Structural deformation and fault activity of the Tan-Lu Fault zone in the Bohai Sea since the late Pleistocene

The Tan-Lu Fault zone (TLFZ) is a significant fractural zone in eastern China and also a seismicity belt in North China. Based on total 4000-km-long shallow penetrated single seismic data with high-resolution, structural deformation and fault activity of the TLFZ in the Bohai Sea since the late Pleistocene are discussed in detail. The results show that the TLFZ with a discontinuous distribution and a general NNE-trending consists of 14 active subfaults with an NNE or NE strike in the Bohai Sea. Seismic data reveal that de-formation zones along the subfaults in the central Bohai Sea and the Laizhou Bay are wider and more complex than those in the Liaodong Gulf. Related folds and lots of secondary normal faults which are characterized by nearly vertical fault planes and a same or reverse dip construct the fractural zone in the Laizhou Bay and the central Bohai Sea. Usually, micro symmetrical grabens develop on the top of anticlines. In the Liaodong Gulf, subfault fractural zones usually consist of secondary normal faults with the same inclination or opposite inclination. Ages of seismic sequences and cutting relation between subfaults and seismic sequences suggest that the latest faulting age of the TLFZ is the end of the late Pleistocene in the Liaodong Gulf and the early Holocene in the Laizhou Bay and the central Bohai Sea. There is a good match between distribution of earthquakes and that of the subfaults in the Laizhou Bay and the central Bohai. Statistical result shows that total vertical offset of the TLFZ since the late Pleistocene ranges from 6 to 11 m. On the basis of offsets of the subfaults, the vertical slip rate is calculated and results show that average vertical slip rates in the central Bohai Sea are larger than those in the Liaodong Gulf and the Laizhou Bay. Slip rates more than 0.06 mm/a during 23–10 ka B.P. and 85–65 ka B.P. are larger than those in other stages. The TLFZ was mainly dominated by tensional normal component since the late Pleistocene. Synthesizing shallow deformation, activity and distribution of earthquakes, the TLFZ in the Bohai Sea can be divided into three segments: the Laizhou-Bay segment, the Bozhong segment, and the Liaodong-Gulf segment.     

The M S7.1 Yushu earthquake surface rupture and large historical earthquakes on the Garzê-Yushu Fault

As revealed by field investigations, the co-seismic surface rupture zone of the 2010 M_S7.1 Yushu earthquake, Qinghai is a char-acteristic sinistral strike-slip feature consisting of three distinct sinistral primary ruptures, with an overall strike of 310°–320° and a total length of 31 km. In addition, an approximately 2-km-long en-echelon tensile fissure zone was found east of Longbao Town; if this site is taken as the north end of the rupture zone, then the rupture had a total length of ~51 km. The surface rupture zone is composed of a series of fissures arranged in an en-echelon or alternating relationship between compressive bulges and tensile fissures, with a measured maximum horizontal displacement of 1.8 m. The surface rupture zone extends along the mapped Garzê-Yushu Fault, which implicates it as the seismogenic fault for this earthquake. Historically, a few earthquakes with a magnitude of about 7 have occurred along the fault, and additionally traces of paleoearthquakes are evident that characterize the short-period recurrence interval of large earthquakes here. Similar to the seismogenic process of the 2008 Wenchuan earthquake, the Yushu earthquake is also due to the stress accumulation and release on the block boundaries resulting from the eastward expansion of Qinghai-Tibet Plateau. However, in contrast with the Wenchuan earthquake, the Yushu earthquake had a sinistral strike-slip mechanism resulting from the uneven eastward extrusion of the Baryan Har and Sichuan-Yunnan fault blocks.     

莫里青断陷西北缘走滑断裂带特征及油气地质意义

通过对莫里青断陷构造、沉积特征及油气成藏规律系统分析,总结出西北缘走滑断裂带演化特征及其对油气勘探的意义。研究结果表明:西北缘断裂成盆期为一条高角度的走滑张性断裂,新近系受挤压应力作用发生反转,形成了内部发育众多具走滑性质的次级逆冲断层、挤压褶皱、花状等构造的西北缘走滑逆冲断裂带;宏观来看西北缘断裂经历了早期走滑拉张和晚期走滑挤压2个演化阶段;西北缘走滑断裂对油气勘探具重要意义:深大断裂通过提供大坡度构造环境、有效物源及保存条件为湖泊水下扇有效储集体形成创造了有利条件,且水下扇中扇辫状水道微相上的油气产能较高;断裂带内部形成断褶皱等构造圈闭、具有挤压性质的逆冲断层封堵油气等因素为油气聚集提供了有效圈闭条件;各条件有效配置使得研究区西北缘走滑断裂带成为较有利的油气富集区带。     

Active deformation of Chinese Mainland from GPS measurement and numerical simulation

Using discontinue deformation analysis(DDA) method we analyzed the characters of the crustal deformation of Chinese mainland in this study form the velocity field revealed by 308 GPS stations. The result shows that the current N-S compression rate and W-E extension rate of the south Tibetan plateau are 1.40 × 10-8/a and 1.81 × 10-8/a, and that of Tiansan block are 2.59× 10-8/a and 0.62× 10-8/a. The Altyn Tagh is a left-lateral strike slip fault with a current slip rate of 8-12 mm/a, and the clockwise rotating rate of Tarim and Gansun-Qinghai block are -8.7 and -8.1 nrad/a, respectively, with respect to the Eurasia plate. According to the boundary condition of Chinese mainland respect to the Eurasia obtained from the DDA model, a two-dimension discontinuous finite element method(DFEM) model was built. Using this model, we evaluated the relationships between the slipping of Altyn Tagh and the crustal deformation and dynamics of Chinese mainland, and found that the slip of Altyn Tagh has influence on compression of Tibetan plateau, rotating of Tarim basin and Gansun-Qinghai block, the region absorbing the energy generated by the collision of Indio Plate and Eurasia plate, the ability and method of energy transferring toward east and the deformation of both Ordos block and North-China block. Further more, the slip of Altyn-Qiliansan Tagh strongly effects the stress field in most part of north-south seismic belt. The crustal deformation and tectonic activities of Chinese mainland west is mainly caused by the block boundary stress generated by the movement of India Plate, and it also influences some area of the east mainland through slipping along Altyn-Qiliansan Tagh. In some Part of east China and south east of China, the small-scale mantle convection and the effect of denudating can not be ignored.