西北内陆盆地平原地下水开采资源分区评价初探

针对西北干旱内陆盆地平原地下水开采资源评价及开发利用中出现的某些环境水文地质问题，结合拟定市（县）年度可采总量和划定超采区与非超采区需要，对地下水允许开采资源、允许降深概念的理解，提出了市（县）地下水允许开采资源分区评价的目的、原则及评价的方法、步骤等     

内陆湖盆"深水成盐"形成条件和识别标志:以东濮凹陷与现代盐湖为例

位于我国东部的许多新生代盆地,在地质历史时期发育了巨厚的岩盐沉积。尽管这些盆地的成盐模式研究已经历了40多年,但由于缺乏“深水成盐”的现代沉积模式,到底是“深盆-深水”还是“深盆-浅水”成盐,一直难以定论。为了理解“深水成盐”的控制因素,很多现代盐湖开展了水文学和水化学调查,然而这些湖盆的矿物组合各不相同,“深水成盐”的形成条件和控制因素尚不清楚。本文对死海、佛瑞湖等“深水成盐”的现代盐湖以及我国东濮凹陷沙三段的成盐特征进行了解剖,从盐度、水深、湖平面波动以及卤水分层等角度探讨了“深水成盐”的形成条件,对比分析了“深水成盐”的相对位置以及沉积物特征,总结了“深水成盐”的识别标志。研究表明,盐岩层系在岩心和测井资料上显示出多尺度的旋回性。“深水成盐”为水深较大的洼陷中心成盐,与盆缘的“浅水成盐”同盆共存。沉积相对岩盐层系的结构和组成有明显的控制作用,其中洼陷带的“深水成盐”,主要在洼陷带的卤水-湖底沉积物界面附近,析出和增生粗晶的盐类矿物,常与富含有机质和黄铁矿的暗色泥岩共存;而湖滨附近的“浅水成盐”,单层厚度薄,结晶粒度细小,通常含有较多的陆源碎屑。死海为代表的现代盐湖以及东濮凹陷等古代成盐盆地的沉积特征表明,“深水成盐”发生于湖平面的下降期,而且卤水剖面的厚度对蒸发岩的形成分布有明显的控制作用,同时具有“深水”和“深盆”特征的内陆盐湖更容易形成单层厚度大、横向稳定的岩盐沉积。本研究有助于改变人们以往对内陆湖盆成盐机理的认知,尤其是现代盐湖的卤水分层析盐特征,对解读地质历史中的其他成盐事件具有重要启示。基于现代沉积实例的“深水成盐”识别标志,可以为古代岩盐沉积模式的建立提供限定条件。     

Dasycladacean alga <Emphasis Type="Italic">Palaeodasycladus</Emphasis> in the northern Tethys (West Carpathians,Poland) and its new palaeogeographic range during the Early Jurassic

The green alga Palaeodasycladus was recognized in Lower Jurassic shallow-marine high-energy calcarenites of the Cho? Nappe (Hronicum Domain) in the Tatra Mts in Poland. This occurrence indicates the most Northern record of Palaeodasycladus as it is known mostly from the southern part of the Western Tethys. The stratigraphic range of Palaeodasycladus (Norian, Sinemurian–Pliensbachian) and the upper Pliensbachian age of the overlying calcarenites (previous data on the basis of brachiopods) suggest that the studied part of the section was deposited during the Sinemurian–early Pliensbachian. The previous and current reports on occurrences of Palaeodasycladus allowed determination of a new northern palaeogeographic range of the shallow-marine Mediterranean biota during the Early Jurassic time.     

Block reinforcement behavior and mechanism of soil slopes

In recent years, blocks created by pressure grouting of cement into soil were used to reinforce slopes by targeting specific weak areas. A clear understanding of the block reinforcement mechanism is essential for the accurate evaluation of the stability of block-reinforced slopes and reasonable design of block layouts. A series of centrifuge model tests was conducted to investigate the bearing capacity and the full deformation and failure behavior of block-reinforced slopes, with a focus on the influence of block layouts on the reinforcement effect. A block reinforcement with a reasonable layout was confirmed to increase the stiffness and the ultimate bearing capacity of the slope. The block reinforcement significantly changed the failure mode to the complex disturbance and destruction from slippage failure in an unreinforced slope. The block reinforcement restrained the deformation localization around the blocks and thus prevented the development of the coupling effect between the deformation localization process and the failure process in an unreinforced slope during loading. Such a reinforcement mechanism could be used to explain why the block reinforcement increased the bearing capacity and changed the failure mode of the slope. The blocks exhibited significant motion along with the development of deformation localization in the slope during loading. The block reinforcement effect was significantly affected by the rotation of blocks, which was determined by the block layout.     

2010—2020年中国老年人口健康水平空间格局演变及其影响因素

把握中国老年人口健康水平空间演变规律对快速老龄化背景下的健康老龄化战略实施具有重要意义。本文基于第六、七次全国人口普查老年人口自评健康数据,采用探索性空间数据分析和重心—时空地理加权回归模型等方法,刻画2010—2020年中国省域城乡老年人口健康水平空间动态演化过程,揭示社会经济发展、人口流动、环境污染与保护等因素的影响变迁,主要发现：① 2010—2020年间中国老年人口健康水平总体上升,但城乡差异进一步扩大,城镇老年人口健康水平“东—中—西”递减格局趋于强化,乡村老年人口健康水平向“南高北低”转变;② 社会经济发展是影响城乡老年人口健康水平及其空间格局演变的首要因素,但作用趋于减弱,乡城人口流动导致老年人口健康城乡差距进一步扩大;③ 环境本底因素作用减弱,环境污染因素作用增强,环境保护举措在城镇地区呈现健康改善效应。     

Dependence between flood peaks and volumes: a case study on climate and hydrological controls

Abstract

The aim of this paper is to understand the causal factors controlling the relationship between flood peaks and volumes in a regional context. A case study is performed based on 330 catchments in Austria ranging from 6 to 500 km² in size. Maximum annual flood discharges are compared with the associated flood volumes, and the consistency of the peak–volume relationship is quantified by the Spearman rank correlation coefficient. The results indicate that climate-related factors are more important than catchment-related factors in controlling the consistency. Spearman rank correlation coefficients typically range from about 0.2 in the high alpine catchments to about 0.8 in the lowlands. The weak dependence in the high alpine catchments is due to the mix of flood types, including long-duration snowmelt, synoptic floods and flash floods. In the lowlands, the flood durations vary less in a given catchment which is related to the filtering of the distribution of all storms by the catchment response time to produce the distribution of flood producing storms.

Editor Z.W. Kundzewicz     

雪峰山西侧震旦纪-早古生代海相盆地演化与油气地质条件

对古地理格架的重新认识和台缘礁滩相的识别是油气勘探突破的关键环节之一。在前人研究的基础上。综合最新的调查研究成果,对雪峰山西侧震旦系-早古生代的重点层系开展了较大比例尺的古地理研究与编图。研究表明,中上扬子海相盆地经历了裂谷盆地（820-720Ma）、被动大陆边缘碎屑岩陆架建设与初始碳酸盐台地（720—540Ma）、被动大陆边缘统一碳酸盐台地的形成与发展（540-490Ma）、淹没台地与前陆盆地充填（490-420Ma）4个大的演化阶段。除第一阶段因热演化程度过高（R0〉3%）外,后3个阶段在雪峰山西侧地区都具有很好的油气地质条件：灯影期、清虚洞期和红花园期台边缘相带发育。陡山沱期、牛蹄塘期、五峰-龙马溪期发育区域性优质烃源岩,黔东世、武陵世和早志留世分别发育区域性厚层泥页岩、含膏岩系和沙泥岩封盖层。生储盖组合完整,油气地质条件优越。系列图件编制和重要认识的提出为深入开展雪峰山西侧地区有利勘探区块优选和评价提供了依据。     

珠峰地区天气气候特征分析

利用珠穆朗玛峰地区北部定日站和西部聂拉木站1971-2009年的月平均气温、月平均最高、最低气温、月降水量、月蒸发量资料,对珠峰地区1971-2009年近39a来气候变化的时空分布特征进行了分析.同时,利用该区域5个自动气象观测站2009年的资料进行了温、压、湿、风等分析.结果表明:1971-2009年珠峰地区气温呈现出明显的上升趋势,尤其是进入21世纪后,增温更为显著,高于同期全球平均温度变化幅度;定日站增幅较聂拉木站明显,且以冬、春两季的气温增长幅度大.位于珠峰的西边略偏北的聂拉木站,迎向暖湿气流,降水丰富,但季节差异很小;定日站的年降水量不到聂拉木站的一半,且夏季降水占到了全年的85%;定日站的年降水量略微呈上升状态,蒸发量下降,两者的变化趋势都不是太明显;聂拉木站的降水量下降趋势比定日站明显,蒸发量略显上升.2009年资料显示,珠峰地区5个站的气温、气压、相对湿度、风速各异,温度、气压与各站的海拔密切相关.     

黔北震旦系灯影组顶部古风化壳特征及油气意义

古风化壳对岩溶储层的形成及油气运聚成藏具有重要的意义。野外地质调查发现黔北震旦系灯影组顶部普遍发育一套黄褐色渣状粘土层,地球化学特征表现为MgO的淋失和SiO2、Al2O3、Fe2O3、Fe2O、P2O5、TiO2不同程度的相对富集,为震旦纪末桐湾运动所形成的古风化壳。该风化壳在不同相带发育程度不尽相同,造成了下伏岩溶储层的差异。台地边缘相区受后期构造抬升影响显著,原生孔隙发育,有利于大气水下渗,岩溶作用强,改善了下伏颗粒白云岩储层,形成了大量的溶蚀孔洞、粒内溶孔、粒间溶孔和裂溶缝;其他相区受岩溶作用改造弱,储层物性较差。因此,黔北隐伏的灯影组滩相-风化壳区应为下阶段油气勘探的重点区域。     

川西峨边地区金口河辉绿岩脉SHRIMP锆石U-Pb年龄及其对Rodinia裂解的启示

川西金口河地区中元古代峨边群中发育大量基性侵入岩,其具体侵位时间对厘定峨边群的时限、研究扬子西缘前寒武纪构造属性具有重要意义。对峨边群枷担桥组层型剖面中一条辉绿岩脉进行了SHRIMP锆石U-Pb定年。结果表明,该辉绿岩脉的锆石发育清楚且宽缓的内部环带结构,具有较高的Th/U比值,属典型基性岩浆成因的锆石,其206Pb/238U年龄加权平均值为(813.4±8.2)Ma(MSWD=0.56),代表了该辉绿岩脉的侵位时间,也限定了峨边群枷担桥组的上限年龄。综合扬子西缘新元古代中期基性岩浆活动的最新同位素年龄,证实存在2个主要的活动期:830~800Ma和780~745Ma,且830~800Ma期间基性岩浆活动的峰值年龄为(821±2)Ma。这与前人总结的华南和澳大利亚同期基性岩浆活动的年龄分布特征完全一致,暗示川西金口河辉绿岩脉的形成可能与新元古代导致Rodinia超大陆裂解的地幔柱幕式活动有关。