柴达木盆地东北部新近纪构造旋转及其意义

青藏高原东北缘构造变形的研究是认识高原隆起过程、机制和印度—欧亚板块碰撞远程效应的重要途径。柴达木盆地是印度－欧亚板块碰撞后南北向挤压应力为动力背景的高原东北部内陆盆地,沉积物主要来自于周边山地,完整的保存了新生代以来高原隆升的详细记录。通过柴达木盆地东北部瑙格剖面精细古地磁及构造旋转研究发现,20.1～15.1Ma以及15.1～8.2Ma柴达木盆地分别发生了9.7°±7.4°和6.4°±4.4°的顺时针旋转,约8.2Ma后,柴达木盆地东北部瑙格地区发生了16°±7.5°的逆时针快速旋转。通过分析认为,前两次的顺时针构造旋转事件可能与阿尔金断裂的左旋走滑有关。而约82Ma以来的逆时针旋转事件属于柴达木盆地东北部瑙格地区的局部旋转,可能与温泉断裂的右旋走滑有关,说明青藏高原东北部在昆仑山、阿尔金山和祁连山三条巨型断裂系左旋相对运动的宏观控制下形成的NNW向温泉右旋走滑断裂开始走滑的年代为约8Ma。     

The relationship between organic matter and specific surface area in <2 μm clay size fraction of muddy source rock

The adsorption of organic matter(OM)onto clay minerals has long been considered as a significant way of OM preservation in source rock.Here we analyzed the relationship between OM and the specific surface area(SSA)of <2μm clay size fraction isolated from 13 source rock cores collected from Dongying depression.Rock-Eval pyrolysis and N2 adsorption experiment were employed to probe the characteristics of OM and SSA(denoted SBET)in samples before and after OM extraction using trichloromethane.The results indicate that various kinds of OM occurrence coexist in clay size fraction and their contributions to hydrocarbon are different in each period of OM evolution.The occurrence and amount of OM affect the S BET of clay size fraction,and a nonlinear negative correlation between total organic carbon(TOC)and S BET can be recognized.The soluble OM(chloroform extract "A"),mainly stored in the pore space of clay size fraction,shows a negative correlation in amount with S BET.Our data also indicate that free hydrocarbon(S1)was stored mainly in the pore space and/or the surface of clay size fraction,whereas pyrolysis hydrocarbon(S2)was mingled mainly with clay minerals.Therefore,to understand various OM occurrences and their relationship with SBET in the clay size fraction is significant in the study of generation,accumulation,and migration of hydrocarbon in muddy source rock.     

赣南崇义淘锡坑钨矿床氢、氧、硫同位素地球化学研究

赣南崇义县淘锡坑钨矿位于南岭东西向构造带东段与武夷山NE-NNE向构造带南段的复合部位,属于以石英脉型黑钨矿为主的钨多金属矿床.文章通过氧、氧、硫同位素地球化学特征的研究,探讨了淘锡坑钨矿成矿流体的来源及演化.研究结果显示:δD值介于-77‰～-45‰之间;石英矿物的δ18O值介于+7.3‰～+12.2‰之间,计算给出...     

浙江桐庐县刘家奥陶纪剖面生物地层学初步研究

新发现的浙江桐庐刘家剖面位于马金一乌镇断裂与球川一萧山断裂之间,是浙西北地区以碎屑岩沉积为主的代表性奥陶纪地层剖面。根据所获得的宁国组和胡乐组的笔石化石,初步建立了该层段的笔石生物地层序列,自下而上包括Tetragraptusapproximatus带、Corymbograptusdeflexus带、Azygograp...     

应用全球定位系统、地理信息系统和遥感技术实现海洋资源与环境的可持续发展

分析了当前我国海洋资源及环境的现状,并提出相应的对策。举例说明了全球定位系统(GPS)、地理信息系统(GIS)和遥感(RS)(合称为3S)在海洋资源调查、环境保护等可持续发展核心问题中的应用,提出一些海洋领域近期亟待应用3S技术的重大课题。指出,“数字海底”和“海岸带”研究是当前海洋研究的切入点,是海洋经济、海洋政治、海洋科学问题的重中之重,与人类生存和发展密切相关。     

STUDY ON THE SEISMOGENIC FAULT CHARACTERSTICS OF 2016 MW5.9 MENYUAN EARTHQUAKE BASED ON Sentinel -1A DATA

In this paper, we processed and analyzed the Sentinel-1A data by "two-pass" method and acquired the surface deformation fields of Menyuan earthquake. The results show the deformation occurred mainly in the south wall of fault, where uplift deformation is dominant. The uplift deformation is significantly larger than the subsidence and the maximum uplift of ascending and descending in the LOS is 6cm, 8cm respectively. Meanwhile, based on the Okada model, we use the ascending and descending passes data as constraints to invert jointly the fault distribution and source parameters through constructing fault model of different dip directions. The optimum fault parameters are:The dip is 43°, the strike is 128°with the mean rake of 85°. The maximum slip is about 0.27m. The inverted seismic moment M₀ is 1.13×10¹⁸N·m, and the moment magnitude M_W is 5.9. The SW-dipping Minyue-Damaying Fault is possibly the seismogenic fault, based on the comprehensive analysis of the focal mechanisms, aftershocks relocation results and the regional tectonic background. The focus property is dominated by thrust movement with a small amount of dextral strike-slip component. The earthquake is the result of local stress adjustment nearby the Lenglongling Fault under the background of northeastward push and growth of Tibet Plateau.     

Evaluating the Tree Population Density and Its Impacts in CLM-DGVM

Vegetation population dynamics play an essential role in shaping the structure and function of terrestrial ecosystems.However,large uncertainties remain in the parameterizations of population dynamics in current Dynamic Global Vegetation Models(DGVMs).In this study,the global distribution and probability density functions of tree population densities in the revised Community Land Model-Dynamic Global Vegetation Model(CLM-DGVM) were evaluated,and the impacts of population densities on ecosystem characteristics were investigated.The results showed that the model predicted unrealistically high population density with small individual size of tree PFTs(Plant Functional Types) in boreal forests,as well as peripheral areas of tropical and temperate forests.Such biases then led to the underestimation of forest carbon storage and incorrect carbon allocation among plant leaves,stems and root pools,and hence predicted shorter time scales for the building/recovering of mature forests.These results imply that further improvements in the parameterizations of population dynamics in the model are needed in order for the model to correctly represent the response of ecosystems to climate change.     

天津地区覆盖层土动力学参数统计分析

收集天津地区近年来有代表性的具有完整土动力学参数作为实验数据的地震安全性评价报告66份,用两种统计方法按不同深度统计分析粉质黏土、黏土、粉土、砂土、淤泥质土等的实测土动力学参数,给出动剪切模量比和阻尼比平均值。选取2个典型工程场地,构建土层分析模型,进行土层地震反应分析计算。结果表明,本文得到的统计2值在天津地区具有一定的代表性和适用性,与实测值结果更为接近。对于获得原状土样困难的场地,特别是对于较薄的夹层土,可参照统计2结果进行分析计算。     

渤海冰情与老虎滩水温的关系

本文对2000～2004年连续5年冬季老虎滩水温与渤海冰面积数据进行统计分析,得到渤海海冰面积与老虎滩水温的回归关系,对冬季海冰预报具有一定的参考意义。     

Estimation of seawater movement based on reflectors from a seismic profile

Seismic oceanography is a new cross-discipline of reflection seismology and physical oceanography. The biggest difference between seismic oceanography and traditional reflection seismology is its research object of time-varied seawater. How to estimate the temporal variations of reflectors in water structure and make some corrections in seismic data are basic problems in seismic oceanography research. Here a method of estimation for seawater movement is provided based on the reflectors. The application results of this method to the simulated and field seismic data turn out to be acceptable. As compared with the previous research, this method has the advantages of low-dependence on migration velocity and dip of reflectors, and it is very suitable for correction in a spectral analysis using seismic data, which is very useful in the research of ocean energy budget.