甘肃玉门—肃南地区砂岩型铜矿赋矿地层特征及其归属

玉门—肃南地区为北祁连西段海相砂岩型铜矿成矿区。区域地层主要为早古生代海相火山-沉积建造。区内天鹿、干沟-老虎沟、牦牛沟、天桥湾、三把羊、红口子6个铜矿床（点）均赋存于下古生界上部地层中。以往对其时代归属存有争议。笔者对区内4个铜矿区的赋矿地层及代表性矿床——天鹿铜矿、鹿角沟及天涝池实测剖面地层特征进一步研究表明,区内砂岩铜矿赋矿地层在岩石组合和地层层序、地球化学等方面与上部晚志留世地层有比较显著的差异。根据区域对比研究表明,区内砂岩铜矿赋矿地层应归属泉脑沟山组上段,时代应为中志留世。     

青海都兰县三色沟铅锌矿区变质岩原岩恢复

对研究区变质岩的岩石学、地球化学研究表明,金水口群中-深变质岩原岩的为一套以火山岩为主的火山-沉积组合。火山岩主要为晶屑凝灰岩、岩屑凝灰岩、角砾凝灰岩、凝灰质砂岩等,属钙碱性岩系。沉积岩为泥灰岩。火山岩构造环境应属活动大陆边缘。     

西非加蓬海岸盆地盐岩特征及其石油地质意义

加蓬海岸盆地主要分为南加蓬次盆和北加蓬次盆,是典型的西非被动大陆边缘含盐盆地,盐岩的分布具有一定规律性和差异性,并且对盆地内油气成藏具有重要的控制作用。分析了加蓬海岸盆地的构造演化与沉积充填特征、基本石油地质条件、盐岩的分布特征及其对盆地烃源岩特征、储层分布、圈闭特征、封盖条件、油气成藏,以及油气藏储量等各方面的影响与控制作用,并指出,由于加蓬海岸盆地的绝大多数油气成藏都与盐岩密不可分,因此深化盆地内盐岩展布特征的研究,对进一步评价北加蓬次盆的盐下层系及南次盆登泰尔地堑的勘探潜力具有重要意义。     

伊宁苏勒萨依井田煤层中瓦斯的分布特征与富集规律

伊宁苏勒萨依井田各煤层为低变质烟煤,瓦斯含量相对较低,以二氧化碳-氮气带为主。在垂向上,瓦斯含量随深度增大总体呈增加之势;在横向上,瓦斯含量自西向东有逐渐升高趋势,其富集地段主要分布于皮里青背斜南冀68线和72线南部一带,建议在矿井开采中,重点监测该地段。严禁超通风能力生产,防止瓦斯大量聚集而引起事故。     

登封箕山北麓硅化破碎带含矿地质特征

登封箕山北麓硅化破碎带主要产于上寒武统白云岩中，成群成带分布。矿化严格受地层、岩性、构造条件控制。本文着重硅化破碎带的含矿地质特征、矿化类型、元素组合、异常分布和围岩蚀变等成矿地质条件分析研究，认为太古代变质绿岩和富钾花岗岩类是“矿源层”，其成因应属低温热液充填型。     

柴北缘铅石山榴辉岩地质特征

根据对铅石山榴辉岩岩石学、岩石化学、地球化学元素、变质岩相及变质作用等特征,该类岩石形成时代可能为中元古代后期,并经历了四堡期、晋宁期、加里东期三次快速折返及相应的退变质作用叠加,进一步证实了柴北缘地区高压变质带的存在。     

山东省海阳市土堆金矿床地质特征

山东海阳土堆金矿床主要赋存于荆山群野头组及侵入其中的新元古代九曲单元二长花岗岩中。矿体多为脉状或透镜状；矿石矿物成分简单，金属矿物以黄铁矿为主，金矿物以自然金、银矿为主。通过分析成矿控制条件认为：荆山群分布区是寻找该类型金矿的地层标志；NE向的断裂带中，绢英岩化、绿泥石化、钾化、硅化、黄铁矿化等蚀变特征是寻找金矿(化)体的围岩蚀变标志，新元古代岩体及燕山晚期脉岩发育是寻找该类金矿的岩浆岩标志。     

A New Inversion Method of Sedimentary Strata For Deriving Double Parameters and Its Applications

The inverse problem of wave equation is the importance of study not only in seismic prospecting but also in applied mathematics. With the development of the research, the inverse methods of 1 - D wave equations have been trending towards the multiple parameters inversion . We have obtained an inverse method with double -parameter, in which medium density and wave velocity can be derived simultaneously. In this paper, to increase the inverse accuracy, the method is improved as follows. Firstly, the formula in which the Green Function is omitted are derived and used. Secondly, the regularizing method is reasonable used by choosing the stable function. With the new method, we may derive elastic parameter and medium density or medium density and wave velocity. Thus, lithology parameters for seismic prospecting may be obtained.After comparing the derived values from the new method with that from previous method, we obtain the new method through which substantially improve the derived accuracy . The new method has been applied to real depths inversion for sedimentary strata and volcanic rock strata in Chaoyanggou Terrace of Songliao Basin in eastern China. According to the inverse results,the gas - bearing beds are determlned.     

Metamorphism and microstructures along a high-temperature metamorphic field gradient: the north–eastern boundary of the Královský hvozd unit (Bohemian Massif, Czech Republic)

A metamorphic field gradient has been investigated in the Moldanubian zone of the central European Variscides encompassing, from base to the top, a staurolite–kyanite zone, a muscovite–sillimanite zone, a K‐feldspar–sillimanite zone, and a K‐feldspar–cordierite zone, respectively. The observed reaction textures in the anatectic metapsammopelites of the higher grade zones are fully compatible with experimental data and petrogenetic grids that are based on fluid‐absent melting reactions. From structural and microstructural observations it can be concluded that the boundary between the kyanite–staurolite zone and the muscovite‐ and K‐feldspar–sillimanite zones coincides with an important switch in deformation mechanism(s). Besides minor syn‐anatectic shearing (melt‐enhanced deformation), microstructural criteria point (a) to a switch in deformation mechanism from rotation recrystallization (climb‐accommodated dislocation creep) to prism slip and high‐temperature (fast) grain boundary migration in quartz (b) to the activity of diffusion creep in quartz–feldspar layers, and (c) to accommodation of strain by intense shearing in fibrolite–biotite layers. It is suggested that any combination of these deformation mechanisms will profoundly affect the rheological characteristics of high‐grade metamorphic rocks and significantly lower rock strength. Hence, the boundary between these zones marks a major rheological barrier in the investigated cross section and probably also in other low‐ to medium‐pressure/high‐temperature areas. At still higher metamorphic grades (K‐feldspar‐cordierite zone), where the rheologically critical melt percentage is reached, rock rheology is mainly governed by the melt and other deformation mechanisms are of minor importance. In the study area, the switch in deformation mechanism(s) is responsible for large‐scale strain partitioning and concentration of deformation within the higher‐temperature hanging wall during top‐to‐the‐S thrusting, thus preserving a more complete petrostructural record within the rocks of the footwall including indications for a ?Devonian high‐ to medium‐pressure/medium‐temperature metamorphic event. Thrusting is accompanied by diapiric ascent of diatexites of the K‐feldspar‐cordierite zone and infolding of the footwall, suggesting local crustal overturn in this part of the Moldanubian zone.     

陕西淳化圣人桥平缓盖层中复杂褶皱的成因——兼论重力滑动构造的分类

陕西圣人桥附近,复杂多样的褶皱出现在平缓的地台盖层之中。对其成因,争议颇多,或认为推覆作用所致,或认为受断裂作用控制。笔者通过详细研究,认为这些复杂褶皱是一种水底重力滑塌构造。据此,还提出了重力滑动构造新的分类,即重力蠕滑;重力滑塌以及重力滑碎等三类。