镇泾地区延长组河流相砂体分布与圈闭形成的关系研究

鄂尔多斯盆地镇泾地区侏罗系地层以三角洲-湖泊沉积体系为主,研究区范围内主要发育主河道和部分分流河道砂体。研究区构造平缓,主要为单斜地层、在东南部存在大型鼻状构造。通过对主要储层段(长6、8油层组)砂体分布及与构造之间关系进行研究,分析砂体走向与构造线方向的关系认为在构造单斜地区,当两者相交时(交角β≠0)是形成圈闭的关键因素之一,在大型鼻状构造地区因构造线的弯曲与河道砂体组合可以形成圈闭。根据研究区砂体分布和构造线组合出4种地层-岩性及岩性圈闭。利用构造图与砂体分布图对主要储层段存在的圈闭确定出长6、8油层组10个层圈闭。     

动力分散型机车在路涵过渡段的动应力-应变研究

运用高性能多通道并行数据采集分析系统,以及BY-1型动静态土压力传感器等测试手段,对动力分散型电力动车组在秦-沈客运专线山绥综合试验段某路涵过渡段的影响进行了试验研究。研究结果表明：动力分散型电力动车组所引起的动应力-应变比较稳定,这对于列车的高速运行是有利的;同时对路涵过渡段线路纵向上动应力-应变特征和变化趋势进行了分析。     

土体应力-应变关系转型问题分析

通过对土体应力应变试验结果的分析,明确指出了土体普遍存在的应力-应变关系转型现象。提出了按后破坏模量和临界围压两个参数判别土体应力-应变关系转型的方法,对影响土体应力-应变关系转型的因素包括土的类型、围压、初始密度或含水率、排水条件及应力路径等进行了简要分析。最后,对砂土初步提出了一个能反映转型现象的组合应力-应变关系模型的理论框架。     

安徽铜陵铜官山矿区中生代岩浆-热液过程：来自岩石包体及其寄主岩的证据

安徽铜陵铜官山矿区的燕山期中酸性-酸性小侵入岩体在时间上和空间上与区内的层控矽卡岩型铜(金)矿床密切相关。在这些小侵入岩体中,特别是在老庙基、小铜官山和金口岭岩体中,产有二长质到闪长质的同源包体、角闪石堆积岩包体和黑云母片岩残余包体。对这三类岩石包体及其寄主岩进行了详细的岩石学和矿物学研究以及单矿物氧同位素分析,同时收集了相关的岩石化学和地球化学资料,为阐明矿区岩浆-热液过程提供了依据。分析结果表明,闪长岩和辉石岩包体的(^87r／^86Sr),为0．7070～0．7073,εM(t)为-9．7,而石英二长闪长岩主岩(^87r／^86Sr)。为0．7072～0．7077,εNd(t)为-10．6～-11．9。铜官山矿区堆积岩包体中的堆积晶、同源包体和寄主岩中的斑晶以及同源包体及寄主岩中的基质的矿物结晶温度分属890～970℃,730～755℃和675～730℃三个区间,对应的深度为24～29km,9～15km和4～6km。它们分别代表了深位岩浆房、浅位岩浆房和岩浆侵位处矿物结晶的温度和深度深位岩浆房的深度对应于岩石圈中下地壳硅镁层的深度,而浅位岩浆房的深度对应于岩石圈中-新元古界浅变质岩系的深度从宕石包体及其寄主岩锶、钕同位素以及岩石学和矿物学资料来看,深位岩浆房中的岩浆可能是由底侵的碱性玄武岩浆与下地壳硅镁层发生相互作用形成的,而浅位岩浆房中的岩浆可能是由来自深位岩浆房的演化岩浆与中-新元古界浅变质岩系发生相互作用形成的。二长质同源包体与黑云母片岩残余包体过渡,有时闪长质同源包体与寄主岩过渡,相互之间的界线模糊不清。角闪石堆积岩包体中金属氧化物和硫化物的共存表明,在堆积岩结晶时已有相当数量的铁、铜和硫溶解在演化的岩浆中。由此可以推断,已初步富集铁、铜和硫的演化岩浆与深度同浅位岩浆房相当且富合成矿元素的变质岩发生同化混染作用,可以富集足够的成矿物质以形成铜官山矿区的矽卡岩型铜铁硫化物矿床,矿区同源包体中斜长石的δ^18OSMOW‰值为9．0～9．2,寄主岩中斜长石和石英为9．4～9．9,矽卡岩中石榴石和石英为3．92～11．84,矿石中磁铁矿和石英为3．84～5.85,而相应的δ^18H2O‰值在寄主岩中为6．87,矽卡岩中为6.85～6.89,矿石中为8．18～12．64。此外,在寄主岩及其岩石包体中同时产有熔融包裹体、熔融-流体包裹体和流体包裹体,并能见到不混溶包裹体。这些事实结合矿物平衡地质温度计计算结果和收集的包裹体测温资料,表明矿区的岩浆-热液过程可以分为：1)岩浆结晶;2)岩浆流体出溶和出溶流体演化(大致对应于矽卡岩化);和3)成矿热液活动(对应于铜金矿化)三个阶段。     

Power and politics in climate change adaptation efforts: Struggles over authority and recognition in the context of political instability

Throughout the world, climate change adaptation policies supported by the United Nations Framework Convention on Climate Change (UNFCCC) have provided significant sources of funding and technical support to developing countries. Yet often the adaptation responses proposed belie complex political realities, particularly in politically unstable contexts, where power and politics shape adaptation outcomes. In this paper, the concepts of authority and recognition are used to capture power and politics as they play out in struggles over governing changing resources. The case study in Nepal shows how adaptation policy formation and implementation becomes a platform in which actors seek to claim authority and assert more generic rights as political and cultural citizens. Focusing on authority and recognition helps illuminate how resource governance struggles often have very little to do with the resources themselves. Foundational to the argument is how projects which seek to empower actors to manage their resources, produce realignments of power and knowledge that then shape who is invested in what manner in adaptation. The analysis adds to calls for reframing ‘adaptation’ to encompass the socionatural processes that shape vulnerability by contributing theoretical depth to questions of power and politics.     

Labour markets in transition. The experiences of women in two border regions of East Germany

The political turning point in the former GDR and the transformation processes that have been observed since then have significantly affected economic and social structures in the new Federal States. Gender roles, however, were subjected to even more dramatic changes. Whilst many women experienced the employment policies of the GDR era as beneficial, social researchers often designate them as the losers of unification nowadays. This is largely because the abundance of State support measures for employed women and mothers has been drastically reduced and women as a group have been hit hardest by the crisis on the East German labour market. Using two cases (Mecklenburg-Westpommerania and Thuringia), this paper aims to illustrate the impact of the transformation process on the everyday (working) lives of women. We are particularly concerned with a comparative analysis of how women experience and deal with regional disparities in East Germany. This revised version was published online in July 2006 with corrections to the Cover Date.     

高压下天然菱铁矿的压缩性和电子结构研究

采用同步辐射光源和金刚石对顶砧(DAC)技术,对天然菱铁矿的压缩性和电子结构进行了原位X射线衍射(XRD)和X射线吸收近边结构谱(XANES)测试研究。在室温下随着压力逐渐升高至50.2 GPa,菱铁矿保持方解石型结构不变,但是逐渐向Na Cl型结构转变;刚性[CO3]2-基团平行于ab-平面定向排列使c轴的压缩性大于a轴。菱铁矿在44.6~47.1 GPa之间发生电子由高自旋态(HS)向低自旋态(LS)的转变,表现为体积塌陷8%。HS菱铁矿的等温状态方程参数为K0=112(5)GPa和K'0=4.6(3)。首次采用XANES技术对菱铁矿中Fe2+的电子结构进行了研究,结果表明:随着压力升高至37.3 GPa,Fe2+的配位和局域对称并未发生明显变化;此后电子结构开始转变,Fe2+的3d轨道分裂能降低,电子跃迁概率增大,呈现LS特性。     

河北康保兴隆遗址的光释光测年研究

兴隆遗址是长城以北裕民文化分期研究的重要遗址。作为坝上高原迄今为止发现的出土遗物最丰富、沿用时间长达数千年的遗址, 其年代的确定不但有助于厘清古人类在这一地区出现的时代, 而且对研究中国北方旧-新石器时代过渡、农业起源及其环境背景等问题具有重要意义。兴隆遗址发掘后, 虽然其新石器文化层已通过¹⁴C方法进行了测年, 但其旧-新石器时代过渡期的文化层尚未进行年代学方面的研究。本研究在地层结构划分基础上, 对兴隆遗址的TG01探沟的G5剖面(42°N, 115°E; 海拔高度为1398m; 剖面研究深度为106~361cm)进行采样, 共采集有11个沉积物样品, 提取出粗颗粒(90~125μm)和细颗粒(4~11μm)两个粒级的石英, 利用光释光(OSL)测年技术中的单片再生剂量法(SAR), 对兴隆遗址探沟的不同文化层位进行年代测定, 建立了兴隆遗址的整体年代框架。通过对两种粒级的石英的释光年代比较, 得出细颗粒石英的所测年龄高于粗颗粒石英, 高出年龄约为600~2000年左右, 这可能是沉积过程的不完全晒退导致的。且基于粗颗粒石英的光释光年龄与¹⁴C年龄之间良好的一致性, 认为粗颗粒石英的光释光年龄更加可信; 并首次确定了兴隆遗址旧-新石器时代过渡期文化层的光释光年龄为距今13.4±1.8~10.7±0.9ka(以粗颗粒石英样品的年代为准)。

     

水沙调节后荆江典型河道横向调整过程的响应——Ⅱ.上、下荆江调整差异初探

三峡水库2003年6月蓄水运用后,下游河道水沙过程已发生大幅变化,对于岸滩抗冲性较弱的荆江河道来说,河道的横向调整过程势必受到影响。采用考虑岸滩崩塌的河势研究数值模型,针对三峡水利枢纽工程运行所引发的水沙变异过程,初步探讨了荆江典型河道横向调整及河势变化对水沙条件变化的响应。对于下荆江石首河段来说,来沙减少后,冲刷加剧,局部河岸坍塌及平面变形加剧,主要发生在受弯道水流顶冲的位置,但河势演变趋势及平面变形总体上基本一致,并未发生较大变化。对于上荆江沙市—新厂河段来说,来沙量减小后,河道平面变形幅度总体上减小,局部最大减幅可达50%左右。     

Sedimentology and sequence stratigraphy of the mixed clastic-carbonate deposits in the Late Paleozoic icehouse period: A case study from the northern Qaidam Basin

The widely-developed, mixed clastic-carbonate succession in the northern Qaidam Basin records the paleo-environment changes under the glacial activity during the Late Paleozoic icehouse period in the context of regional tectonic stability, however, the depositional environment and sequence stratigraphy characteristics of the mixed deposits is rarely reported and still not clear. Combined the latest drilling wells data, we analyzed the sedimentary and stratigraphic characterization of the mixed strata via detailed field outcrops and core observations and thin section microscopic observations and recognized three depositional systems, including progradational coastal system, incised valley system, and carbonate-dominated marine shelf system, and identified four third-order sequences, SQ1, SQ2, SQ3 and SQ4, consisting of LST, TST, and HST. The depositional environment is overall belonged to marine-continental transition context and shifted from marine to continental environment frequently, showing an evolutionary pattern from marine towards terrestrial-marine transition and then back into the marine environment again in the long-term, which was controlled by the regional tectonic subsidence and the high-frequency and large-amplitude sea-level changes due to the Late Paleozoic glacial activity. The result is of significance in understanding the evolution of the Qinghai-Tibet Plateau and the sedimentation-climate response.©2021 China Geology Editorial Office.