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961.
通过对阳谷-齐河凸起地下热水的化学成分、同位素及其地热地质条件的分析,对这一地区的地下热水的补给来源进行了研究。本区地下热水的δD为-65‰~-80.67‰,δ18O为-9.2‰~-10.2‰,均分布在全球雨水线的附近,说明该区地下热水主要为大气降水成因。济南北地热田地下热水的补给高程为256m,此范围大致相当于济南南部山区及其以南的泰山北麓;聊城东地热田地下热水的补给高程为411m,此范围大致相当于泰山山脉及其周边的中山区。聊城东地热田地下热水的2H过量参数d明显低于济南北地热田,说明聊城东地热田地下热水的补给区比后者更远。  相似文献   
962.
林萌 《中国煤炭地质》2010,(11):18-21,41
借鉴油气藏数值模拟理论、技术和方法,对单一松软煤层的瓦斯抽采工艺进行了研究分析。根据单一松软煤层特点,提出了单一松软煤层的几何模型技术——单直径球型孔隙模型,在此基础上建立了煤层瓦斯抽采的地质和数理模型,并根据网格差分方法推导出数值解。以实际生产数据对新模型及其数值解进行验证,结果表明该模型可以用于指导单一松软煤层瓦斯抽采工艺的确定。  相似文献   
963.
根据相干体技术原理和主要参数选取原则,对五阳矿区进行了以断层和陷落柱为主要研究对象的解释工作。应用实例表明:相干体技术可有效解决本区断层断点较多、切割关系复杂、空间展布规律难以把握和常规解释误差较大等问题;同时,对不规则环状相邻陷落柱的边界及直径较小的陷落柱都有十分灵敏的反映,特别是对较大断层附近的微小构造也可作出较为可靠的解释。  相似文献   
964.
In southern California, USA, wildfires may be an important source of mercury (Hg) to local watersheds. Hg levels and Hg accumulation rates were investigated in dated sediment cores from two southern California lakes, Big Bear Lake and Crystal Lake, located approximately 40-km apart. Between 1895 and 2006, fires were routinely minimized or suppressed around Big Bear Lake, while fires regularly subsumed the forest surrounding Crystal Lake. Mean Hg concentrations and mean Hg accumulation rates were significantly higher in Crystal Lake sediments compared to Big Bear Lake sediments (Hg levels: Crystal Lake 220 ± 93 ng g−1, Big Bear Lake 92 ± 26 ng g−1; Hg accumulation: Crystal Lake 790 ± 1,200 μg m−2 year−1, Big Bear 240 ± 54 μg m−2 year−1). In Crystal Lake, the ratio between post-1965 and pre-1865 Hg concentrations was 1.1, and several spikes in Hg levels occurred between 1910 and 1985. Given the remote location of the lake, the proximity of fires, and the lack of point sources within the region, these results suggested wildfires (rather than industrial sources) were a continuous source of Hg to Crystal Lake over the last 150 years.  相似文献   
965.
The present work investigated the adsorption and mobility (desorption) of Sb(V) on kaolinite using batch experiments. The adsorption of Sb(V) on kaolinite was studied as a function of contact time, pH, ionic strength, humic acid (HA), initial Sb(V) concentration and temperature. Kinetic studies suggest that the equilibrium is achieved within 24 h. The adsorption of Sb(V) was strongly affected by changes in I at low ionic strength and unaffected at high ionic strength. The adsorption is weakly dependent on the presence of humic acid, but is strongly dependent on pH. Within the range tested, the optimal pH for Sb(V) adsorption is 3.6, and close to 75% removal can be achieved. Desorption is dependent on the original suspension pH. The addition sequence of Sb(V)/HA do not influence the adsorption of Sb(V) on kaolinite. The adsorption data fit both the Freundlich and Langmuir isotherm. The thermodynamic parameters (ΔH 0, ΔS 0 and ΔG 0) were calculated from the temperature dependence, and the results suggest the endothermic and spontaneous nature of the process.  相似文献   
966.
巢湖市内汤池、半汤、香泉、昭关等四大温泉,水温42—63℃,日出水量达1万m~3,储量丰富,水质优良。近年来,不断提升巢湖市温泉资源的开发利用和保护水平,温泉度假旅游已成为巢湖旅游业的拳头产品。2009年12月,经国土资源部和中国矿业联合会专家评审,巢湖市被命名为中国温泉之乡。  相似文献   
967.
About half of the lunar meteorites in our collections are feldspathic breccias. Acquiring geochronologic information from these breccias is challenging due to their low radioactive-element contents and their often polymict nature. We used high-spatial-resolution (5 μm) NanoSIMS (nanoscale secondary ion mass spectrometry) U-Pb dating technique to date micro-zircons in the lunar feldspathic meteorites Dhofar 1528 and Dhofar 1627. Three NanoSIMS dating spots of two zircon grains from Dhofar 1528 show a discordia with an upper intercept at 4354 ± 76 Ma and a lower intercept at 332 ± 1407 Ma (2σ, MSWD = 0.01, p = 0.91). Three spots of two zircon grains in Dhofar 1627 define a discordia with an upper intercept at 3948 ± 30 Ma and a lower intercept at 691 ± 831 Ma (2σ, MSWD = 0.40, p = 0.53). Both samples likely experienced shock metamorphism caused by impacts. Based on the clastic nature, lack of recrystallization and the consistent U-Pb and Pb-Pb dates of the zircons in Dhofar 1528, the U-Pb date of 4354 Ma is interpreted as the crystallization age of its Mg-suite igneous precursor. Some of the Dhofar 1627 zircons show poikilitic texture, a crystallization from the matrix impact melt, so the U-Pb date of 3948 Ma corresponds to an impact event, likely the Imbrium basin-forming event. These data are the first radiometric ages for these two meteorites and demonstrate that in situ (high spatial resolution) U-Pb dating has potential for extracting geochronological information about igneous activities and impact events from lunar feldspathic and polymict breccias.  相似文献   
968.
This research investigated eight stations in Clarion-Clipperton Fracture Zone(CCFZ) in the eastern tropical Pacific in 2017 to study the spatial distribution characteristics of nutrients and chlorophyll a(Chl a) concentration,and compared nutrient concentrations and molar ratios with those of other investigations 20 years ago in the same area. The study found that dissolved inorganic nutrient(N, P and Si) concentrations were lowest in the upper layer, and increased from surface to some depths, t...  相似文献   
969.
Spartina alterniflora as an alien invasive plant, poses a serious threat to the ecological functions of the coastal wetland of the Jiaozhou Bay. As of 2019, the distribution area of S. alterniflora in the Jiaozhou Bay has reached more than 500 hm2. For this reason, combined with field surveys, remote sensing monitoring of the invasion S.alterniflora in the Jiaozhou Bay has been carried out. To accurately identify S. alterniflora within the Jiaozhou Bay coastal wetland, we used a new m...  相似文献   
970.
Seismicity in ocean ridge-transform systems reveals fundamental processes of mid-ocean ridges, while comparisons of seismicity in different oceans remain rare due to a lack of detection of small events. From 1996 to2003, the Pacific Marine Environmental Laboratory of the National Oceanic and Atmospheric Administration(NOAA/PMEL) deployed several hydrophones in the eastern Pacific Ocean and the northern Atlantic Ocean.These hydrophones recorded earthquakes with small magnitudes, providing us with...  相似文献   
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