共查询到17条相似文献，搜索用时 78 毫秒
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溶蚀孔洞是塔河油田奥陶系碳酸盐岩的主要储渗空间,因此研究碳酸盐岩岩溶测井响应特征以弄清其发育规律具有重要意义.在分析研究区内的岩溶地质特征之后,根据钻井揭示的岩溶型储集层,对岩心、测井特征进行了对比和归纳梳理,进而提炼了奥陶系岩溶发育带的测井响应特征.结合前人对岩溶风化壳发育的控制因素和分布特征的研究,依托岩心和成像测井资料刻度的岩溶带常规测井响应特征,在垂向上将岩溶层划分为表生岩溶带、垂直渗流岩溶带和水平潜流岩溶带,并对其分布规律进行了研究.结果表明:研究区地表岩溶带较发育,且基本属于未充填-半充填,是有利储集层发育的层位;潜流岩溶带不甚发育,基本被充填.总体上看,自东南向西北,溶洞发育带的分布密度逐渐增大,表明古岩溶作用的强度向西北方向逐渐增强. 相似文献
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萍-乐坳陷带为江西省最主要的隐伏岩溶发育区带之一,岩溶地层发育,地表水、地下水循环交替强烈,地质构造复杂,为岩溶的发育、岩溶地下水的富集提供了良好的条件。查明岩溶发育规律及岩溶水的富集特征,可为地下水资源合理开发与地质环境保护提供科学依据。 相似文献
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笔者 1999— 2 0 0 3年在华北太行山区和北京地区多次进行洞穴调查 ,发现很多古地震遗迹。文中论述了岩溶古地震研究的原理与依据 ,以及岩溶古地震遗迹的主要特征与岩溶古地震标志 ,对辨别洞穴正常岩溶现象与岩溶古地震遗迹的问题提出了新的方法 ,指出了在岩溶古地震调查时应注意的问题 相似文献
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灰岩地区岩溶发育对城市建设有着极大的威胁,一般岩溶探测主要采用钻探勘探,很难充分反映地下岩溶发育规模与特征,而跨孔电磁波层析成像方法,能查明工区地下岩溶发育及延伸情况.对钻孔间地层进行电磁波层析成像正演,表明电磁波层析成像对岩溶勘察的准确性与可行性.结合地铁轨道交通岩溶勘察实例,应用电磁波层析成像技术反演电磁波吸收系数... 相似文献
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为减小岩溶区地质灾害带来的损失,以广西岩溶区为例,分析了广西岩溶地质的分布特点,对广西岩溶区的工程地质灾害进行研究分类,对岩溶区工程场地处理方法进行研究,综述了地表封闭防渗法、地面下加固处理法、结构物跨越法三大方法的原理、实施效果和实用性。研究发现:由于降雨和地下岩石类别差异等因素,广西的岩溶分布类型具有强烈的地域特性,形成了三大岩溶地貌特征;产生岩溶区地质灾害最主要的诱因是地下水的变化,重要工程中定时定点监控地下水变化十分重要;广西的岩溶区溶洞和土洞塌陷主要是人为因素造成的。 相似文献
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A new method of estimating the fractal dimension of the percolation backbone of karst systems, which are discharged through karst springs, is presented. This method is based on the simulation of the spring by the MODKARST deterministic mathematical model. Application has been made to the Psiloritis karst formation in Crete, which feeds the periodically brackish karst spring “Almiros” in Crete. Furthermore, the estimated dimension justifies an independently determined power law that quantifies the sea intrusion into the karst system. 相似文献
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The thick-bedded and continuous karst crust only formed in the old stage of geomorphic development. The corresponding landscape
is the karst planation surface. The karst planation surface consists of the loose weathering crust and the base weathering
front below the crust. Its profile structure is similar to “double surface of leveling” model built by Budel. In the limestone
area, the base weathering front is the covered karst. From the Tibet Plateau to Yun-Gui (Yunnan-Guizhou) plateau and Xiang-Gui
(Hunan-Guangxi) hills, the covered karst is concomitant with the red weathering crust; all of them are the component of the
double-level surfaces of karst planation. But, they belong to the different disintegration stages of planation surface. The
different subtypes of the covered karst and the red weathering crust indicate the existence of karst planation surface. Thus,
they can be made as a reference system when the rising degree and the rising rate of the Tibet Plateau are discussed. 相似文献
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In China, 9·5% of the landmass is karst terrain and of that 47,000 km2 is located in semiarid regions. In these regions the karst aquifers feed many large karst springs within basins of thousands of square kilometres. Spring discharges reflect the fluctuation of ground water level and variability of ground water storage in the basins. However, karst aquifers are highly heterogeneous and monitoring data are sparse in these regions. Therefore, for sustainable utilization and conservation of karst ground water it is necessary to simulate the spring flows to acquire better understanding of karst hydrological processes. The purpose of this study is to develop a parsimonious model that accurately simulates spring discharges using an artificial neural network (ANN) model. The karst spring aquifer was treated as a non‐linear input/output system to simulate the response of karst spring flow to precipitation and applied the model to the Niangziguan Springs, located in the east of Shanxi Province, China and a representative of karst springs in a semiarid area. Moreover, the ANN model was compared with a previous time‐lag linear model and it was found that the ANN model performed better. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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Mark Grasmueck Miquel Coll Quintà Kenri Pomar Gregor P. Eberli 《Geophysical Prospecting》2013,61(5):907-918
Vertical fractures with openings of less than one centimetre and irregular karst cause abundant diffractions in Ground‐Penetrating Radar (GPR) records. GPR data acquired with half‐wavelength trace spacing are uninterpretable as they are dominated by spatially undersampled scattered energy. To evaluate the potential of high‐density 3D GPR diffraction imaging a 200 MHz survey with less than a quarter wavelength grid spacing (0.05 m × 0.1 m) was acquired at a fractured and karstified limestone quarry near the village of Cassis in Southern France. After 3D migration processing, diffraction apices line up in sub‐vertical fracture planes and cluster in locations of karstic dissolution features. The majority of karst is developed at intersections of two or more fractures and is limited in depth by a stratigraphic boundary. Such high‐resolution 3D GPR imaging offers an unprecedented internal view of a complex fractured carbonate reservoir model analogue. As seismic and GPR wave kinematics are similar, improvements in the imaging of steep fractures and irregular voids at the resolution limit can also be expected from high‐density seismic diffraction imaging. 相似文献
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The paper presents an attempt to determine the characteristics of karst aquifers using information on groundwater level (GWL) in natural holes and boreholes with different data quantity and time resolution of GWL measurements. In this paper the particulars of karst aquifers were analysed for four examples from the Dinaric karst. In all four study areas, aquifers are formed in bare, deep and well‐developed Dinaric karst consisting of Cretaceous limestones. The first example represents a wide area of Imotsko polje in the karst. The aquifer was analysed on the basis of infrequent water level monitoring in natural karst water features (jamas, lakes, wells) and discharges of springs and rivers. The karst aquifer in this example is complex, non‐homogenous and variable in space and time, which is frequent in the Dinaric karst. Regardless of the aforementioned it was possible to determine its elementary characteristics. The second example represents 10 wells used for the water supply for the city of Pula. The GWL and salinity were measured once a week in the period between 1981 and 1996. Even though these measurements were relatively infrequent in space and time, they served as bases for assessment of average and maximum aquifer conditions as well as boundaries of saltwater intrusion. In the third example only a portion of aquifer of the karst spring Blaz, which is in the contact with the Adriatic Seas, has been analyzed. It is a spring with an intrusion of salt water. For purposes of study of saltwater intrusion, 26 piezometers were drilled in its vicinity in which GWL, salinity and temperature were measured once a day during 168 days, a period comprising one complete cycle of seawater intrusion and retreat. These measurements proved the existence of dispersed discharge from the aquifer into the sea and its non‐homogeneity in space. In the fourth example GWL was measured continuously in 10 deep (up to 300 m) piezometers in the hinterland of the Ombla Spring catchment. The measurement period lasted 2 years (January 1988 to December 1989). The analyses are made with hourly data. The results made it possible to determine numerous characteristics of the karst aquifer and a significant non‐homogeneity of groundwater distribution in karst aquifers, depending more on the underground karst phenomena than the surface karst forms. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献