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北京北部地区深层热水开发对浅层冷水的影响 总被引:1,自引:1,他引:0
北京北部有小汤山和沙河2个地热田,呈三角形展布,东部边界为黄庄-高丽营断裂,西部边界为南口-孙河断裂.北部边界为阿苏卫-小汤山断裂。热储层为蓟县系雾迷山组、铁岭组和寒武系-奥陶系碳酸盐岩岩溶裂隙含水层.热储盖层为青白口系页岩、石炭系-二叠系砂页岩和侏罗系火山岩隔水层。该区雨水、浅层基岩冷水和深层基岩热水的H、O同位素组成基本上都落在克雷格降水线上,表明区内冷水与热水均来源于大气降水。热水的^3H值表现出北高南低的特点.说明热水与冷水一样自北向南流动。重点分析了深层热水开采对浅层地震观测井中冷水动态的影响,以及这种影响在不同的水文地质条件、离开采井不同距离和不同测项方面表现出的差异。结果表明,北京北部深层热水开采对浅层冷水动态的影响距离约为5km.对位于导水断裂带附近的观测井的影响最为明显。 相似文献
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井中声波CT技术系统及其应用 总被引:1,自引:0,他引:1
叙述了井中声波CT技术系统的测量方式、数据采集和数据预处理以及CT正反演的基本方法, 列举了在工程勘察和油气田开发中的应用实例,显示出井中声波CT成果为查明目标体的位置和圈定目标体的形态是有效的。同时也显示了井中声波CT技术作为一种精细勘查手段,具有开发潜力和应用前景。 相似文献
646.
The Curie point depth of continental crust can reflect the regional tectonic pattern and geothermal structures. Analysis of magnetism is an efficient way to obtain the Curie point depth on a regional scale. This study systematically investigated the Curie point depth of Sulu (苏鲁) ultrahigh pressure (UHP) metamorphic belt (33°40'N to 36°20'N and 118°E to 120°E, ca. 60 000 km2), eastern China using aeromagnetic data. The results show that the Curie point depth of the Sniu region varies from 18.5 to 27 kin. The shallowest Curie point depth (ca. 18.5 km) is located in Subei (苏北) subsidence, where the estimated temperature gradient value is about 31.35℃/kin, which is comparable with the measured value of 30℃/krn. In addition, a two-dimensional numerical solution of the heat conduction was used to calculate the temperature field to a depth of 30 km along the profile from Tancheng (郯城) to Lianshui (涟水) with a length of 139 km. The steady state model solved using the finite element method shows that the temperature around the Curie point depth is about 585.36℃, which is close to the Curie temperature (580 ℃) of magnetite at atmospheric pressure. These results provide new insights into the tectonic and continuous thermal structures of the Sulu UHP metamorphic belt. 相似文献
647.
A GeoVision Micro™ colour video camera was used to investigate the internal structure of 11 boreholes at Haut Glacier d'Arolla, Switzerland. The boreholes were distributed across a half-section of the glacier, with closest spacing towards the glacier margin. The boreholes were used to investigate the hydrology of the glacier through automatic monitoring of borehole water level and electrical conductivity (EC) at the glacier bed. EC profiling was undertaken in several boreholes to determine the existence of water quality stratification. Temporal variations in EC stratification were used to infer borehole water sources and patterns of water circulation. Borehole video was used to confirm the conclusions made from these indirect sources of evidence, and to provide an independent source of information on the structure and hydrology of this temperate valley glacier. The video showed variations in water turbidity, englacial channels and voids, conditions at the glacier bed and down-borehole changes in ice structure. Based on the video observations, englacial channels accounted for approximately 0·1% of the vertical ice thickness, and englacial voids for approximately 0·4%. Overall, the video images provided useful qualitative and semi-quantitative data that reinforce interpretations of a range of physical and chemical parameters measured in boreholes. © 1997 by John Wiley & Sons Ltd. 相似文献
648.
Steady-state numerical simulations of the dipole flow test in layered aquifers demonstrate that the test produces a good estimate of the equivalent hydraulic conductivity anisotropy ratio for the part of the aquifer spanned by the well chambers. The effects of chamber size, different conductivity of layers and layer location on the estimated anisotropy ratios are presented. The steady-state dipole flow test, when performed at different levels in the well, can yield estimates of the down-hole anisotropy ratio distribution. Numerical simulations also illustrate that the skin effect can significantly distort the anisotropy estimates produced by the dipole flow test. © 1997 John Wiley & Sons, Ltd. 相似文献
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Nyemo-Nagqu, Tibet, is rich in high-temperature geothermal resources. The geothermal fields in Yangbajain and Yangyi as well as 11 unexplored geothermal fields along the geothermal belt from Nyemo to Nagqu were systematically investigated and the hydrochemistry data were collected from the whole field. Meanwhile, H-O-C-S isotope data were obtained for the new fields, and H-O isotope data for the Yangbajain and Yangyi fields. A comparison of the Nyemo-Nagqu geothermal fields with those in the Yangbajain area shows that the types of high-temperature geothermal water are dominated by Cl-Na and Cl·HCO_3-Na, while the types of medium-high-temperature geothermal water are dominated by HCO_3-Na. The concentrations of Li, F, SiO_2, and HBO_2 in the geothermal water are positively correlated with Cl content, indicating possible mixing with magma water. The reservoir temperatures range from 90 to 270°C by geothermometers. Slight drifting of ~(18)O was recorded at the Dongweng and Nyingzhong high-temperature geothermal fields, while more significant drifting was recorded at Gulu. The geothermal water is mainly replenished by atmospheric precipitation. The low tritium contents(1 TU) of the geothermal water from Nyingzhong, Gulu, and Luoma indicate that it is mainly replenished by sub-modern(prior to 1952) water, while the high tritium content(8.4 TU) in Yuela implies modern water replenishment. Other geothermal fields are replenished by a mix of sub-modern fresher water. The isotopic data in this study show that the carbon and sulfur in the geothermal water originates mainly from sediment leaching, with some of the carbon and sulfur having a deep origin. 相似文献