Geological analysis and FT dating of the large-scale right-lateral strike-slip movement of the Red River fault zone

Tectonically, the large-scale right-lateral strike-slip movement along the Red River fault zone is char-acterized at its late phase with the southeastward extension and deformation of the Northwestern Yunnan normal fault depression on its northern segment, and the dextral shear displacement on its central-southern segment. Research of the relations between stratum deformation and fault movement on the typical fault segments, such as Jianchuan, southeast Midu, Yuanjiang River, Yuanyang, etc. since the Miocene Epoch shows that there are two times dextral faulting dominated by normal shearing occurring along the Red River fault zone since the Miocene Epoch. The fission track dating (abbrevi-ated to FT dating, the same below) is conducted on apatite samples collected from the above fault segments and relating to these movements. Based on the measured single grain’s age and the con-fined track length, we choose the Laslet annealing model to retrieve the thermal history of the samples, and the results show that the fault zone experienced two times obvious shear displacement, one in 5.5 ± 1.5 MaBP and the other in 2.1± 0.8 MaBP. The central-southern segment sees two intensive uplifts of mountain mass in the Yuanjiang River-Yuanyang region at 3.6―3.8 MaBP and 1.6―2.3 MaBP, which correspond to the above-mentioned two dextral normal displacement events since the late Miocene Epoch.     

An 8.1Ma calcite record of Asian summer monsoon evolution on the Chinese central Loess Plateau

Carbonates in loess-red clay sequences consist mainly of calcite and dolomite. The EDTA analysis of carbonates in different size fractions and magnetic susceptibility reveal that calcite is a sensitive index of summer monsoon. The chemical analysis of carbonates and calcite from an 8.1 Ma loess-red clay sequence at Chaona on the Chinese central Loess Plateau shows that the evolution of the Asian summer monsoon experienced four stages, namely 8.1―5.5 Ma, 5.5―2.8 Ma, 2.8―1.5 Ma and 1.5―0 Ma, with increasing intensification and fluctuation, suggesting a possible combining impacts of uplift of the Tibetan Plateau and global changes on the Asian summer monsoon.     

大底盘多塔楼结构的混合隔震控制

结合某实际工程,针对大底盘多塔楼结构提出混合隔震的控制策略,即对大底盘上的一栋或多栋塔楼采用隔震技术,并在隔震层附设一定数量的被动、主动或半主动的减震控制装置。建立了这种大底盘多塔楼结构混合隔震控制体系的运动方程,方程中各塔楼与下部结构及隔震层之间的刚度解耦,并考虑了隔震层的非线性。研究中比较了被动非线性粘滞阻尼器,半主动变孔隙阻尼器与理想主动控制时的减震控制效果。结果表明,这种混合隔震体系可以有效地减小上部塔楼与下部结构的地震反应,提高大底盘多塔楼结构的抗震安全性,取得明显的经济和社会效益。半主动变孔隙阻尼器可以极好地追踪理想主动控制力,取得与理想主动控制相近的减震控制效果。被动非线性粘滞阻尼器也能取得较好的减震效果,且易于维护,经济性较好,从工程应用的角度来看更为现实可行,具有较好的应用推广价值。     

1954年山丹7.3级地震灾害

1954年2月11日,中国西部河西走廊发生山丹7.3级强烈地震,这是建国以来发生在西北地区的第一个大地震。地震造成47人死亡,332人受伤,数万人无家可归;房屋损坏7277间,估计财产损失远高于2003年山丹6.1级地震灾害的直接经济损失。极震区烈度达Ⅺ度,红寺湖盆地、山丹县城破坏最重,山丹地区受灾面积4800km2。本文简要介绍了山丹地震参数、地震烈度及震区环境;重点描述了房屋建筑物破坏,分析了地震灾害特点及其经济损失估计。最后探讨了这次地震震害的成因、防震减灾的经验及其借鉴意义。     

Ternary geochemical-tracing system in natural gas accumulation

The establishment of geochemical-tracing system of gas generation and accumulation is helpful to re-elucidating the gas migration and accumulation in time and space. To deduce the complex process of gas accumulation, a ternary geochemical-tracing system is set up, according to stable isotope inheritance of source rocks, kinetic fractionation of stable isotopes, time-accumulating effect of noble gas isotopes, mantle-derived volatile inheritance, and organic molecule inheritance of light hydrocarbons and thermally kinetic fractionation in their generation, in combination with the previous achievements of gas geochemistry and geochemical parameters of gas-source correlation. There are tight interactions for the geochemical parameters with much information about parent inheritance and special biomarkers, in which they are confirmed each other, reciprocally associated and preferentially used for the requirement so that we can use these geochemical parameters to effectively demonstrate the sources of natural gas, sedimentary environments and thermal evolution of source rocks, migration and accumulation of natural gas, and rearrangement of natural gas reservoirs. It is necessary for the ternary geochemical-tracing system to predict the formation of high efficient gas reservoir and their distribution in time and space.     

修正的莫尔-库仑理论的解析和验证

根据主应力可分解为静水应力和偏应力,以及它们在应力莫尔圆和变形方面的相关性,推导出修正的莫尔-库仑理论的数学表达式。从理论上解决了库仑理论和莫尔理论存在的许多缺陷,特别是中间主应力对材料抗剪强度的影响。它的四参数准则的计算结果与一些混凝土的试验数据相当吻合。     

煤炭资源勘查规范的进步与发展——新型煤炭资源地质勘查法规体系的构建思维

在贯彻执行我国现行有关煤炭资源勘查规范及相关规定的基础上，对国际国内煤炭地质勘查阶段划分进行了对比，论述了建国以来中国煤炭地质勘查规范的主要技术内涵，对加强贯彻新规范，促进标准化体系建设和适应社会主义市场经济体制改革进行了探讨。     

对建设水文数据仓库的初步研究

本文根据目前对水文信息的应用需求,提出了建设水文数据仓库的必要性。对数据仓库及相关技术作了简要介绍,结合水文数据实际状况和应用主题,提出了建设水文数据仓库的数据组织、基本体系结构和建设步骤等相关内容。     

青藏高原新生代火车头山碱性及钙碱性两套火山岩的地球化学特征及其物源讨论

藏北羌塘火车头山新生代火山岩可区分为钙碱性及碱性两个不同的系列。钙碱性火山岩主要岩石组合为玄武岩-安山岩-英安岩,其SiO_2介于49%～70%之间,Al_2O_3>10%,Na_2O/K_2O>1;其中玄武岩具平坦型稀土配分型式,LREE/HREE为1.3～1.8,(La/Yb)_N为2.87～4.45,无明显铕异常,δEu为0.96～1.09;该套岩石的Mg~#与SiO_2相关关系以及La/sm-La等亲岩浆元素与超亲岩浆元素协变关系表明,它们应为幔源岩浆经分离结晶演化的产物,其岩石组合类型以及低的Sm/Yb值(Sm/Yb=1.53～5.35)表明它们的原始岩浆应来源于岩石圈地幔尖晶石二辉橄榄岩的局部熔融。本区碱性火山岩为一套典型的钾质岩石系列,主要岩石组合类型为碱玄岩-碱玄质响岩-响岩,其SiO_2介于44%～59%之间,Al_2O_3>14%,Na_2O/K_2O介于0.47～1.51之间;岩石轻稀土强烈富集,LREE/HREE为13.20～15.76,(La/Yb)_N=50.44～91.99;其岩石组合类型以及Mg~#与SiO_2相关关系以及La/Sm-La协变关系同样表明它们为共源岩浆分离结晶演化的产物;然而,其较高的Sm/Yb值(Sm/ Yb=2.63～13.98)表明它们并非地幔橄榄岩直接局部熔融的产物,岩石弱的负Eu异常(δEu=0.77～0.85)以及Th、U的强烈富集和Nb、Ta的相对亏损,又反映了原始岩浆中有显著的地壳物质的贡献;该套钾质碱性系列岩石在La/Co-Th/Co同分母协变图上呈直线型分布,而在La/Co-Sc/Th异分母协变图上呈显著的双曲线分布,从而表明其源区为二源混合型,是青藏高原特殊的壳幔混合层局部熔融的产物,这些特征是新生代青藏高原壳幔层圈物质交换的重要岩石学证据。     

内蒙古赛乌素金矿床成矿地质特征及找矿预测

赛乌素金矿床位于华北板决北缘、狼山-白云鄂博裂谷带白云鄂博群浅变质岩系内.矿床成因属浅成中低温热液型金矿床,矿石类型以石英脉型为主,尖灭再现、膨大收缩、雁列侧伏特征明显.区内哈拉忽鸡复背斜及EW、NW向断裂为主要控矿构造,具多期性、叠加性特点.根据区域金成矿规律、控矿地质条件、探采对比以及隐伏矿体的发现,证实南北矿带具备中深部和边部找矿潜力.