Groundwater management by riverbank filtration and an infiltration channel: the case of Obrenovac, Serbia

The Vi? Bare groundwater source is used to supply water to the population and industry of Obrenovac, one of the municipalities of Belgrade (the capital of Serbia). It is a typical riverbank filtration site; exploitation is performed through 30 drilled wells and two radial wells located in the meander of the Sava River. The established hydraulic connection between the river and tapped aquifer is so great that the river regime has a dominant influence on the aquifer. As a consequence of this, water-delivery reduction occurs in the dry months (summer–autumn), when the population needs water the most. Based on the data associated with the river’s gauges, precipitation, quantity of pumped water and groundwater-level fluctuation, a simulation of the groundwater regime for non-steady-state flow conditions has been undertaken through a numerical model. To overcome problems of water shortage during the dry season, the possibility of artificial recharge using an infiltration channel, made up of two connected parts, was analyzed. During the dry months, 80 % of the wells receive water partly from the infiltration channel. In this way, possibilities for extracting additional water are created. The application of this concept is discussed.     

鄂尔多斯盆地东南部上古生界层序地层格架及含气砂体沉积演化特征*

鄂尔多斯盆地长期存在“南油北气”的固有认识,晚古生代早期砂体不发育与分布规律不清的认识,长期制约了盆地东南部天然气勘探开发的步伐。因此,加强盆地东南部上古生界煤系含气地层地质方面的研究、尤其是层序地层与储集砂体成因研究,对进一步增储上产具有重要理论与实践意义。作者采用Vail经典层序地层理论与方法,对鄂尔多斯盆地东南部上古生界进行层序地层研究: 首先对层序界面进行识别,以岩性、旋回和沉积特征变化作为识别依据,并提出二级层序界面上下岩性组合变化巨大、二级界面之上叠置的低位砂厚度巨大的观点,共将本溪组—石盒子组划分为3个二级层序,11个三级层序;其次根据层序内部砂体堆积、迁移样式对体系域进行了划分。通过大量钻井的层序单元追踪对比与岩心精细描述,重点分析层序格架内主要含气层段本溪组、山西组及盒8段储集砂体的空间叠置关系,结合不同时期基准面旋回变化及其形成机制对其进行探讨,认为优势含气层段储集层中本2段具有障壁迁移、毯式连通,山2段具有低位控砂、面线连通,山1段具有侧向迁移、接触式连通,盒8段具有迁摆叠置、多向连通的特点。     

鲁西新泰孟家屯2.7Ga变质沉积岩与黑云斜长片麻岩锆石Hf同位素特征

对出露于山东新泰孟家屯2.7Ga的孟家屯岩组中石榴石石英岩(M08)、含十字石石榴石黑云母石英片岩(D242-Y2)和黑云斜长片麻岩(M03)(TTG质片麻岩)进行锆石Lu-Hf同位素分析。石榴石石英岩锆石核部176Lu/177Hf、176Hf/177Hf变化范围为0.001730～0.002546、0.281249～0.281360,锆石变质边部176Lu/177Hf、176Hf/177Hf变化范围为0.000123～0.002070、0.281241～0.281318;含十字石石榴石黑云母石英片岩锆石核部176Lu/177Hf、176Hf/177Hf变化范围为0.001334～0.002169、0.281226～0.281324,锆石变质边部176Lu/177Hf、176Hf/177Hf变化范围为0.000445～0.001375、0.281227～0.281309;黑云斜长片麻岩锆石176Lu/177Hf、176Hf/177Hf变化范围为0.000315～0.000847、0.281186～0.281265。孟家屯岩组石榴石英岩、含十字石石榴石黑去母石英片岩中碎屑(岩浆)锆石和黑云斜长片麻岩中岩浆锆石的εHf(t)分别为3.75～7.26、2.31～7.26和3.21～6.27,同时TDM1与其U-Pb年龄非常接近,表明它们起源于新生地壳的部分熔融。结合区域研究资料认为,2.7Ga是鲁西重要的一期构造岩浆热事件,也可能是华北克拉通重要的构造岩浆活动时期。变质沉积岩中许多变质增生锆石相对于核部岩浆锆石低176Lu/177Hf、高176Hf/177Hf,显示变质作用过程中石榴石的存在对锆石的Lu-Hf同位素体系有很大影响。     

PAN－S光度法测定水和河泥中微量锰

本文研究了ＰＡＮ－Ｓ与锰的显色反应。配合物的最大吸收峰位于５３８ｎｍ波长处，表观摩尔吸光系数为２．９×１０￣４Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１），锰量在０─１．６μｇ／ｍｌ范围内符合比尔定律，方法用于水和河泥中微量锰的测定，结果良好。     

壳幔成矿学初探

壳幔成矿学是联结深部地质学与区域成矿学的重要桥梁,将成矿作用与深部过程联系起来,进行壳幔成矿学研究,已成为当今区域成矿学的一种重要发展趋势,壳幔成矿学研究的核心内容是大陆壳幔多层圈相互作用与成矿关系,而壳幔成矿学研究的主要技术支撑是“岩石探针”分析,壳幔成矿学研究应选择若干典型区域,采用演化历史分析与作用过程鉴别结合的思路,对岩包体及其寄生主岩和有关矿床进行深入研究,以查明区域壳幔相互作用事件幕与     

Paleogene of the Huanghekou Sag in the Bohai Bay Basin,NE China: deposition–erosion response to a slope break system of rift lacustrine basins

The sequence architecture and depositional systems of the Paleogene lacustrine rift succession in the Huanghekou Sag, Bohai Bay Basin, NE China were investigated based on seismic profiles, combined with well log and core data. Four second‐order or composite sequences and seven third‐order sequences were identified. The depositional systems identified in the basin include: fan delta, braid delta, meander fluvial delta, lacustrine and sublacustrine fan. Identification of the slope break was conducted combining the interpretation of faults of each sequence and the identification of syndepositional faults, based on the subdivision of sequence stratigraphy and analysis of depositional systems. Multiple geomorphologic units were recognized in the Paleogene of the Huanghekou Sag including faults, flexures, depositional slope break belts, ditch‐valleys and sub‐uplifts in the central sag. Using genetic division principles and taking into consideration tectonic features of the Paleogene of the Huanghekou Sag, the study area was divided into the Northern Steep Slope/Fault Slope Break System, the Southern Gentle Slope Break System and T10 Tectonic Slope Break System/T10 Tectonic Belt. Responses of slope break systems to deposition–erosion are shown as: (1) basin marginal slope break is the boundary of the eroded area and provenance area; (2) ditch‐valley formed by different kinds of slope break belts is a good transport bypass for source materials; (3) shape of the slope break belt of the slope break system controls sediments types; (4) the ditch‐valley and sub‐sag of a slope break system is an unloading area for sediments; and (5) due to their different origins, association characteristics and developing patterns, the Paleogene slope break belt systems in the Huanghekou Sag show different controls on depositional systems. The Northern Fault Slope Break system controls the deposition of a fan delta‐lacustrine‐subaqueous fan, the Southern Gentle Slope Break system controls the deposition of a fluvial–deltaic–shallow lacustrine and sublacustrine fan, and the T10 Tectonic Slope Break System controls the deposition of shallow lacustrine beach bar sandbodies. The existence of a slope break system is a necessary but not a sufficient condition for studying sandbody development. The formation of effective sandbodies along the slope break depends on the reasonable coupling of effective provenance, necessary association patterns of slope break belt, adequate unloading space and creation of definite accommodation space. Copyright © 2013 John Wiley & Sons, Ltd.     

川西北地区中三叠统顶部溶蚀型喀斯特特征及地质意义*

中三叠统顶部溶蚀型喀斯特在什邡金河剖面及四川盆地大部分地区已有报道。在近期的野外工作中,在川西北地区绵竹汉旺观音崖、江油黄莲桥和江油马鞍塘剖面天井山组近顶部、顶部也识别出这一古特提斯面,其形成与强烈的构造活动或全球海平面下降造成的岩层长时间的暴露有关。其表现形式主要为: (1)暴露溶蚀间断沉积面;(2)溶沟、溶缝及其内的碳酸盐、陆源碎屑充填物;(3)暴露期黏土层;(4)喀斯特角砾。其中暴露溶蚀间断沉积面上的沉积构造以鸟眼、层状孔洞构造最为典型,在绵竹汉旺观音崖剖面最为发育,孔、洞充填物主要为亮晶方解石和白云石;溶沟、溶缝及其内的碳酸盐、陆源碎屑充填物在江油马鞍塘、汉旺观音崖、什邡金河等剖面均有发育,这些溶缝、溶沟一般近于竖直发育,宽度及深度不一,被碳酸盐角砾、亮晶方解石、白云石或陆源黏土等所充填;暴露期黏土层主要见于江油黄莲桥剖面,共发育2套,厚5~20 cm,与铁质矿物共生,其上下发育深灰色潟湖沉积;喀斯特角砾主要见于汉旺观音崖剖面,喀斯特角砾最大可达15×20 cm大小,呈棱角状充填于富含泥质和有机质的暗色碳酸盐基质中。天井山组近顶部溶蚀型喀斯特的发现可为区域地层等时对比提供依据,与其有关的古岩溶作用可在天井山组(或雷口坡组)顶部碳酸盐岩中形成以溶蚀孔、洞、缝为主要储集空间的古岩溶型储集层。     

Data Mining for Landslide Genetic Mechanism Analysis in the Yunnan Province of China

Landslide susceptibility analysis based on the strong ability of data mining of Geographic Information System (GIS) has become a hot topic in international landslide research. This paper used optimized decision tree and GIS databases to analyze the sensitivity in the northwest mountain areas of Yunnan province of China, and then discussed the formation mechanism of the landslide happened in the area. The translational landslide located in the area with an average gradient less than or equal to 28.7° was reclassified as a higher level 3 sensitive area than before according to the normalized different fault index (NDFI). The results showed that the data mining based on GIS 3D space–time information database can help to find the unique topography, geology hydrology and the other typical spatial information of some special typed of landslides such as translational landslides, thus it can illustrate the relationship between the landslides and their sensitivity factors. The improved landslide susceptibility analysis will provide a new method for identifying the genetic mechanism of landslide, and play an important role in the government regional planning and disaster prevention measures.