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Li J.-F.,China University of Geosciences | Shang Z.-W.,Chinese Academy of Geological Sciences | Fan C.-F.,Chinese Academy of Geological Sciences | Tian L.-Z.,China University of Geosciences | And 2 more authors.
Geological Bulletin of China | Year: 2010

Based on 6 leveling sections across the tidal zone of Tianjin Binhai New Area, the height and slop of tidal zone were measured and calculated. The elevation of the interface between anthropogenic coastline (seawall, coastal road and so on) and the natural tidal zone is from +0.22 m~+0.73 m (1956 Huanghai Elevation System). The slop results of the tidal zone show that the average slop of Tianjin tidal zone is 1.25‰, and the average slop of tidal zone on the south Haihe River is 1.09‰ and of the north is 1.33‰. The slop increases from Chengtougu (1.21‰) to Dashentang (1.58‰) section. Based on tide observation data, the width of tidal zone were obtained and the results show that the widest one is Yongdingxinhe tidal zone, 1730~1810 m, and the narrowest one is Dashentang tidal zone, 1900~1160 m. The slop of the tidal zone increases and the width of the tidal zone become narrow from 1980s to now. Furthermore, the elevation of the interface between anthropogenic coastline and the natural tidal zone were lower than mean high water level, which reveals a situation that the artificial constructions are influenced by sea water directly now. This paper presents that the coastal embankment has really become the only barrier protecting the urban safety, so further heightening, strengthening coastal defense facility, upgrading prevention level is necessary.

Yu Z.,Jilin University | Guo L.,Jilin University | Zhang Y.,Jilin University | Xu T.,Jilin University | And 2 more authors.
Environmental Earth Sciences | Year: 2016

Ground-source heat pumps (GSHPs) have been widely applied in China in recent years. However, for heating-dominant buildings in cold regions, more heat from the ground is extracted than rejected, which leads to an annual decrease in heat source temperature and degradation of GSHP heating performance. In this study, a novel medium- to low-temperature enhanced geothermal combined with heat pump system (MLEGHP) is proposed for winter heating. Taking Shenyang city as an example, we technologically and economically investigate the applicability of this novel MLEGHP system in heating-dominated regions over a 30-year period. According to real geological data, hydraulic fracturing simulation, reservoir simulation, heating performance assessment, and economic analysis are conducted successively. Results indicate that the MLEGHP system can continuously work efficiently without performance deterioration and strengthen heating reliability during long-term operation in cold regions. Despite the high initial investment, the heat production and payback period of the system are considerable for large-scale projects. Thus, the MLEGHP system is a potential solution for the underground thermal imbalance of GSHP systems and for winter heating in cold regions. © 2016, Springer-Verlag Berlin Heidelberg.

Yu R.,China University of Geosciences | Tang Y.,Tianjin Geothermal Exploration and Development Designing Institute
Jilin Daxue Xuebao (Diqiu Kexue Ban)/Journal of Jilin University (Earth Science Edition) | Year: 2015

The newly discovered Wheerclt molybdenum deposit is located in the Erlian-Dongwuqi molybdenum metallogenic belt. Its geochemical characteristics and U-Pb age have been researched in this paper. The results show that ore-forming porphyry belongs to a peraluminous and high potassium calcium alkaline serie. The geological features, such as enrichment of large-ion lithophile elements (LILE) and the depletion of high field strength elements (HFSE), show a similar rock combination as Nanling type. U-Pb dating of the zircon from the porphyry by LA-ICP-MS indicates that the metallogenesis related granitic porphyries are formed in Middle Jurassic ((160±1) Ma) in Wheerclt molybdenum deposit. It is deduced that Wheerclt porphyry deposit was formed in Early Yanshan Period. According to a comprehensive research, the formation of Wheerclt porphyry molybdenum deposit was formed in a post-collisional setting. ©, 2015, Jilin University Press. All right reserved.

Yang F.,CAS Institute of Geology and Geophysics | Yang F.,Jilin University | Pang Z.,CAS Institute of Geology and Geophysics | Lin L.,Tianjin Geothermal Exploration and Development Designing Institute | And 4 more authors.
Applied Geochemistry | Year: 2013

Deep saline aquifers are considered as the most promising option for geologic disposal of CO2. One of the main concerns, however, is the integrity of the caprocks between and above the storage formations. Here, a hydrogeochemical and isotopic investigation is presented, using ionic chemistry, stable isotopes (δ18O, δ2H and 87Sr/86Sr) and radiocarbon dating, on five saline aquifers on a regional scale, namely: Neogene Minghuazhen, Guantao, Ordivician, Cambrian and Precambrian, all found in the Bohai Bay Basin (BBB) in North China. Groundwater recharge, flow pattern, age and mixing processes in the saline aquifers show that the Neogene Guantao Formation (Ng) in the Jizhong and Huanghua Depressions on both of the west and east sides of the Cangxian Uplift is a prospective reservoir for CO2 sequestration, with a well confined regional seal above, which is the clayey layers in the Neogene Minghuazhen Formation (Nm). However, this is not the case in the Cangxian Uplift, where the Ng is missing where structural high and fault zones are developed, creating strong hydraulic connections and trans-formational flow to the Nm aquifer. Comparing storage capacity and long-term security between the various hydrogeologic units, the depressions are better candidate sites for CO2 sequestration in the BBB. © 2012 Elsevier Ltd.

Chen R.-J.,Tianjin Geothermal Exploration and Development Designing Institute | Li Y.-Y.,Tianjin Geothermal Exploration and Development Designing Institute | Jia Z.,Tianjin Geothermal Exploration and Development Designing Institute
Jilin Daxue Xuebao (Diqiu Kexue Ban)/Journal of Jilin University (Earth Science Edition) | Year: 2010

In Tianjin Banqiao depression, the Dongying Formation contains abundant ground pressure-type geothermal fluid resources. Because the exploitable water level is deep, both survey and development of the resource are difficult for local government. Combining with the pore structure and ground pressure of Dongying Formation, the authors analyzed the data of the pumping test of well TR21 and suggested that Dongying Formation is in overpressure condition, having a starting hydraulic gradient. By iterative fitting of the data from 0 and 3 stage drawdown pumping test, the calculated starting hydraulic gradient is 1.16(1160‰)and the overpressure coefficient of permeability is 1.896 m/d. These data indicate that the geothermal fluid of Dongying Formation receives recharged from the underlying overpressure Shahejie Fomation. Dongying Formation can trap underlying strata overpressure of 5.12-6.25 MPa which provides the probability for the formation of overpressure of underlying strata and the preservation of overpressure of the Dongying Formation. The overpressure coefficient of permeability is higher than the one obtained(1.392 m/d) by permeability, suggesting that the coefficient of permeability of geothermal reservoirs increases under overpressure conditions. The overpressure and increase of coefficient of permeability of the reservoir facilitate the exploitation of the resources.

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