安徽省江淮分水岭地区水资源问题及对策

地下水资源贫乏，水(境外地表水)工程地质环境恶化(引水干渠的边坡滑塌)，地表水难以蓄存，是安徽江淮分水岭地区经济发展滞后的重要原因。本文通过对区内水资源分析，提出了改善的相关对策。     

Şarköy-Mürefte 1912 Earthquake's Tsunami, extension of the associated faulting in the Marmara Sea, Turkey

The historical tsunamis in the Marmara Seawere mainly caused by earthquakes andneeded to be documented. Following 1999Izmit earthquake occurred at the EasternMarmara region, a complete inventory ofactive faults in the Marmara Sea regionbecame much more stressed. To the west, thelatest event is 09.08.1912arköy-Mürefte Earthquake. Itoccurred on the active Ganos Fault zone andwas one of the largest earthquakes in theBalkans. The eastern termination of theassociated faulting is in the deep WestMarmara Trough, westernmost of thesuccessive basins forming the Marmara Sea.On the basis of recent multibeam bathymetryand seismic reflection data, estimatedtotal length of the surface rupture isabout 56 km. The historical data reviewedfrom library and archive documents,geological field surveys and offshoregeophysical investigations have shown thatthe 1912 earthquake produced a tsunami. Inaddition a seabed dislocation, the sourceof 1912 tsunami can also be assigned to thesediment slumps appearing in the form ofechelon landslide prisms along the southernslopes of the West Marmara Trough.     

准噶尔盆地石南地区清水河组一段层序地层特征

清水河组一段是石南31井区岩性油藏、石南44井区微幅构造油藏及整个腹部地区的重要产层，探究其层序地层特征对于指导研究区及整个腹部地区清水河组一段的隐蔽油气藏勘探有重要意义。通过对岩心、测井、地震等资料综合分析，指出清水河组一段相当于下白垩统第一个三级层序的低位及湖侵体系域。其层序地层特征显著，表现为:低位体系域以沟谷残余可容纳空间充填沉积为特点，分布较为局限，沟谷主要沉积辫状河道砂砾岩；湖侵体系域以退积型三角洲和三角洲前缘滑塌浊积扇沉积为主。建立了石南31井区的成藏模式，并指出三南凹陷中西部是岩性—地层油气藏勘探的有利区带。沟谷砂砾岩及三角洲前缘滑塌浊积扇可形成岩性圈闭，退积型三角洲可形成地层超覆圈闭；湖侵体系域顶部的泥岩可做为区域盖层；斜坡古地貌、深大断裂—中浅层断裂系统与不整合匹配为有效的输导体系。     

南海东北部陆坡与恒春海脊天然气水合物分布的地震反射对比

经过对"探宝号"调查船在2001年8月在南海东北部陆坡及台湾南部恒春海脊海域采集的多道地震剖面资料进行的地震反射波数据分析、研究和解释,结果表明:(1)南海东北部陆坡段区域和台湾南部恒春海脊海域地震剖面上均显示有被作为天然气水合物存在标志的BSR,但两区域构造成因、形式和相关地质环境的不同造成了此两处的天然气水合物成因及过程的不同.(2)南海东北部陆坡区域的水合物形成与该区广泛发育的断裂带、滑塌构造体及其所形成的压力场屏蔽环境有关,而台湾南部恒春海脊海域的天然气水合物的形成则与马尼拉海沟俯冲带相关的逆冲推覆构造、增生楔等及其所对应的海底流体疏导体系有关.(3)南海陆缘区域广泛发育有各种断裂带、滑塌构造体、泥底辟、俯冲带、增生楔等,且温压环境合适,是天然气水合物矿藏极有可能广泛分布的区域.     

The late Quaternary sedimentary infill of Lake Annecy (northwestern Alps): an overview from two seismic-reflection surveys

The sedimentary fill of Lake Annecy (northwestern Alps) - related to the last glacial/post-glacial episode - was investigated through high resolution (sparker) and very high resolution (2.5 kHz) seismic-reflection surveys. A seismostratigraphic approach led to subdivision of a 150 m-thick pile (maximum thickness in axial part) into five units. Basal units (1 and 2) represent an imbrication of subglacial and glacio-lacustrine deposits, close to the grounding line of the glaciers' fronts (respectively at the northern and southern terminations of the lake). The first acoustically well-stratified unit (3) developed during a fast retreat of the glaciers fronts far from the lake basin, and a progradational alluvial regime, with abundant underflows, in a lake larger than the present one. Unit 4 represents the progressive decrease of this clastic input mixed with the progressive development of in situ bio-induced production. As in many other alpine lakes, a topmost unit (5), relatively thin (about 8-10 m) and with a conspicuous drape configuration, is the signature of the Holocene interglacial climatic conditions with a sedimentation rate of about 1 mm/yr. On the lacustrine basin slopes, slumps and debris flow occurred mainly within Unit 3; they may be due to, either climate-induced high rate terrigenous sedimentation, or/and to a period of increased seismo-tectonic activity.     

Sur la structure,l'âge et l'origine des « brèches de Bosmendiette » (Pyrénées-Atlantiques)

By us considered as Albo-Aptian in age and generated through halokinetic processes, the Bosmendiette breccias have been recently interpreted as Selandian (Palaeocene) globigerine-bearing sediments deposited in sub-marine canyons within a deep trough crossing the Pyrenees, from the Mediterranean Sea to the Atlantic Ocean. These breccias are really azoic in their lower part and contain a scarce microfauna including radolarians and benthic foraminifera at the top of the formation. They are unconformably covered by the Urgo-Aptian limestones and marls and indicate, under opening marine conditions, Lower Cretaceous collapse movements and northward sliding of the Jurassic slumped cover, related to the growth of the Béloscare–Apoura diapir. To cite this article: J. Canérot et al., C. R. Geoscience 336 (2004).     

青藏高原多年冻土区热融滑塌变形现场监测分析

为了了解青藏高原多年冻土区K3035里程热融滑塌体的变形特征,分别在未滑动土体、近滑塌前缘滑体中布设了2个变形监测孔,利用Geokon-603型测斜仪实施了近1 a的变形监测。结果表明,发育在平缓斜坡上的热融滑塌具有明显的变形特征,其位移主要发生在土层浅部,越往深部,位移越小,这一监测结果通过室内数值模拟得到了验证。将阳坡的K3035热融滑塌与阴坡的K3057热融滑塌体的变形做了对比监测,无论是滑塌体后缘还是前缘,前者的滑动变形均显著大于后者。而无热融滑塌发育的斜坡(青藏铁路DK1139)土体变形量极小,这种差异一方面说明了开挖是导致热融滑塌发生的直接因素,另一方面,由于热融滑塌的影响,其后缘相对稳定的原斜坡土体也处于相对较大的蠕变变形之中。     

顺倾边坡岩层滑移弯曲临界长度及其影响因素分析

基于顺倾边坡岩层滑移弯曲的弹性微分方程及其精确解,应用能量原理建立了岩层滑移弯曲失稳的临界长度计算式,归纳出主要影响因素,并应用优势分析法探讨了各影响因素的主次关系。分析结果表明：岩层单层厚度、滑移面力学性质、岩体弹性模量和坡角是影响顺倾边坡岩层滑移弯曲的主要因素,其影响程度由大到小依次为岩层单层厚度、滑移面的力学性质、岩层倾角和弹性模量。     

冻土斜坡模型试验相似分析

南水北调工程、青藏铁路建设工程等一系列工程的实施,将进一步影响和加剧青藏高原多年冻土区斜坡稳定性问题,冻土区边坡开挖及斜坡稳定性是工程活动中必须解决的问题之一,冻土斜坡稳定性研究在国内尚属空白。通过相似模型试验对高原多年冻土区斜坡在自然和人类活动影响下的失稳机制和活动规律进行分析,是开展研究的重要手段。根据相似理论第一定律,对冻土斜坡模型试验进行了相似分析,应用积分类比法推导并建立了冻土斜坡模型试验的相似指标和相似判据,得出在用原状土作模型介质时,6个相似常数减少为2个相似常数,即cτ和cl。模型与原型的时间比例尺是由几何比例尺决定的,即cτ=c2l,仅有一个相似参数为自变量,另一个为因变量。据此对青藏高原多年冻土区青藏公路沿线K3035处冻土斜坡进行了相似模型设计和冻融模型试验。模型再现了K3035处7°斜坡在4个冻融循环条件下,坡体中部(水平、垂向)4#位移伸张计质点位移曲线随时间的变化特征。实验表明,斜坡土体中部在第一次冻融循环中已有滑动迹象,随着滑坎进一步后退和靠近观测基准点,必然出现一次较大的位移,直至周边土体出现滑塌为止。模型试验结果与现场观测资料相比较是令人满意的。