Palaeozoic late collisional strike-slip deformations in Tianshan and Altay, Eastern Xinjiang, NW China

ABSTRACT In Central Asia, thrusts and shear zones resulting from Palaeozoic accretional events were reworked by E–W-trending ductile strike-slip faults during late Palaeozoic–early Mesozoic time. In the Tianshan range, microstructures and quartz C-axis fabrics show a main dextral shearing associated with sinistral localized shear zones. The relationship between these conjugate structures indicates a NNW–SSE-trending bulk shortening. In the Chinese Altay mountains, the existence of δ-type microstructures in an important sinistral mylonitic zone infers high rates of deformation. This shear zone is bordered by a late dextral ductile fault synchronous with a granite emplacement. Field evidence and datings from the literature provide chronological constraints. In the late Carboniferous, the sinistral mylonitic deformation took place in the Erqishi–Irtysh shear zone in the northeastern part of Xinjiang and in Kazakhstan. During the Early Permian, a regional dextral event occurred in the Tianshan range and under the whole of northern Xinjiang.     

胜利油气区东营凹陷现今地温场研究

文中利用热导率分散模型,根据地层中砂质含量数据计算东营凹陷第三系各沉积地层单元的原地热导率,再利用热阻率法根据东营凹陷１７０口测温井中测温资料计算出第三系各地层界面上和特征深度处温度,进而研究东营凹陷现今地下温度。计算结果表明,第三系各地介面上地温分布特征主要受各界面埋藏深度控制,而地下各特征深度上地温分布特征主要受热流平面分布特征控制。     

Thermal-rheological structure of the lithosphere beneath two types of basins in eastern and western China

After calculating thermal-rheological properties of the lithosphere in the Northern Jiangsu basin, the Bohaiwan basin as well as the Jiyang depression in the east and Tarim basin in the west of China, this paper analyzes the relationship between thermal-rheological structures and tectonic evolution of the two types of basins. The results show that the thermal-rheological structures of the lithosphere directly reflect the dynamic processes. Under different dynamic environments, the style of basin formation and the differences in basin evolution are closely related to the dynamic properties of the lithosphere indicated by thermal-rheological structures.     

SPOT6遥感图像融合方法比较研究

SPOT6是2012年法国新发射的遥感卫星,具有空间分辨率高、数据采集能力强等特点,但目前在国土资源监管中,尚未形成完善的SPOT6数据处理技术体系。针对SPOT6卫星图像的特点,借助ENVI,ERDAS和PCI等遥感图像处理软件平台,选取相位恢复(Gram-Schmidt)变换法,高通滤波(HPF)法,超分辨率贝叶斯(Pansharp)法和Pan Sharpening法等4种图像融合方法进行融合对比实验,并从3个方面对融合效果进行了评价:首先对融合结果进行图像质量的定性评价;其次,构建了平均值、标准差、信息熵、平均梯度和相关系数等5个评价指标,对融合效果进行定量评价;最后,借助地物分类精度评价方法,进行了融合后图像的应用效果评价。分析结果表明,对于不同的应用要求,应选择不同的图像融合方法,以期达到最好的应用效果,从而为SPOT6图像在国土资源监管中的应用提供技术支持。     

江西井冈山鹅岭隧道的工程地质调查与涌水量预测

江西井冈山鹅岭隧道是新建衡阳-茶陵-吉安铁路的关键性控制工程,洞身全长10 455 m,最大埋深750 m。该隧 道的地质构造复杂,断裂发育,岩石破碎,水量丰富。其涌水量是该隧道设计和施工的重要参数。在区域地质和构造调 查的基础上,本研究选择不同渗水岩性段进行了多口钻井（DK）及其水文地质试验,获得了一批宝贵的第一手隧道工程 地质和水文地质资料和数据。通过对这些资料和数据的分析和研究,确定了不同地质体的出水量和渗透系数。继而,按 钻井位置将该隧道划分为9 个不同涌水区段,运用不同方法对各个区段的涌水量进行了精细计算,预测5 个区段涌水量大, 分别为DK7+280-DK7+550（最大赋水段）、DK6+625-DK7+280（中等赋水段）、DK8+875-DK10+085（中等赋水段）、 DK11+570-DK11+770（中等赋水段）和DK13+570-DK13+930（中等赋水段）,施工过程中很可能产生突发涌水现象,建 议施工设计中采取有效防护措施,高度重视这些区段的工程质量。实践证明,本文的研究结果对嗣后的该隧道设计和施工 发挥了积极的指导作用,提高了施工质量。     

巨型花岗岩带与大陆聚合—裂解作用成因联系研究进展

围绕巨型花岗岩带与大地构造之间的成因联系,回顾了人们对全球超大陆聚合与裂解作用的研究进程,总结了古元 古代哥伦比亚超大陆、新元古代罗迪尼亚超大陆、新元古代晚期-早古生代原冈瓦纳大陆以及晚古生代-中生代潘吉亚超 大陆形成与演化过程的研究进展,结合收集自中国华南、塔里木、华北、青藏等构造单元的地质资料,分析了四期大陆聚 合作用与裂解过程的基本特征和发生时间的不等时性,及其对巨型花岗岩带形成与分布以及矿产资源的制约关系,明确了 超大陆演化对巨型花岗岩带及其矿产资源研究的重要意义。同时,提出了已有研究中的若干薄弱环节,对今后可能实现的 创新与突破进行了展望。     

闽西南玮埔岩体和赣南菖蒲混合岩锆石La—ICPMSU-Pb年代学：对武夷山加里东运动时代的制约

闽西玮埔岩体和赣南菖蒲混合岩位于武夷山构造带南部地区.对NNE向展布的闽西玮埔岩体两个样品进行了锫石La-ICPMS U-Pb测年,获得的年龄为447.1±4.7Ma·和440.8±3.4Ma,证明这个岩体不是原来认为的印支期花岗岩,而属于加里东岩体.赣南菖蒲混合岩发育于罗浮岩体的北侧,早期将罗浮岩体归于燕山早期岩体.对混合岩进行的锫石La-ICPMS U-Pb测年,获得的年龄为445.9±3.8Ma,确定这个岩体为加里东期.这些新的高精度年龄学数据为武夷山加里东构造运动时限和性质提供了精确约束.     

Mesozoic-Cenozoic Basin Features and Evolution of Southeast China

The Late Triassic to Paleogene(T_3-E) basin occupies an area of 143100 km~2,being the sixth area of the whole of SE China;the total area of synchronous granitoid is about 127300 km~2;it provides a key for understanding the tectonic evolution of South China.From a new 1:1500000 geological map of the Mesozoic-Cenozoic basins of SE China,combined with analysis of geometrical and petrological features,some new insights of basin tectonics are obtained.Advances include petrotectonic assemblages, basin classification of geodynamics,geometric features,relations of basin and range.According to basin-forming geodynamicai mechanisms,the Mesozoic-Cenozoic basin of SE China can be divided into three types,namely:1) para-foreland basin formed from Late Triassic to Early Jurassic(T_3-J_1) under compressional conditions;2) rift basins formed during the Middle Jurassic(J_2) under a strongly extensional setting;and 3) a faulted depression formed during Early Cretaceous to Paleogene (K_1-E) under back-arc extension action.From the rock assemblages of the basin,the faulted depression can be subdivided into a volcanic-sedimentary type formed mainly during the Early Cretaceous(K_1) and a red -bed type formed from Late Cretaceous to Paleogene(K_2-E).Statistical data suggest that the area of all para-foreland basins(T_3-J_1) is 15120 km~2,one of rift basins(J_2) occupies 4640 km~2,and all faulted depressions equal to 124330 km~2 including the K_2-E red-bed basins of 37850 km~2.The Early Mesozoic (T_3-J_1) basin and granite were mostly co-generated under a post-collision compression background, while the basins from Middle Jurassic to Paleogene(J_2-E) were mainly constrained by regional extensional tectonics.Three geological and geographical zones were surveyed,namely:1)the Wuyishan separating zone of paleogeography and climate from Middle Jurassic to Tertiary;2)the Middle Jurassic rift zone;and 3)the Ganjiang separating zone of Late Mesozoic volcanism.Three types of basin-granite relationships have been identified,including compressional(a few),strike-slip(a few), and extensional(common).A three-stage geodynamical evolution of the SE-China basin is mooted:an Early Mesozoic basin-granite framework;a transitional Middle Jurassic tectonic regime; intracontinental extension and red-bed faulted depressions since the Late Cretaceous.     

新疆卡拉麦里蛇绿岩带中硅质岩的放射虫化石

新疆卡拉麦里构造带在奇台县南明水地区可划分为三个岩石一构造单元：①北带，由中泥盆世复理石组成；②南带，由中泥盆世—早石炭世沉积岩—火山质碎屑岩组成；③蛇绿岩带。三者之间均为断裂接触。蛇绿岩套上部单元的红色硅质岩中发现丰富的放射虫化石，经鉴定，其时代确定为晚泥盆世法门期一早石炭世杜内期，代表卡拉麦里蛇绿岩形成的晚期年龄。