郴州华塘煤矿采空区地面塌陷的影响因素及防治措施探讨   总被引：1，自引：0，他引：1  

李守贤  陈荣华  申俊 《地质灾害与环境保护》2007,18(3):19-22

郴州华塘煤矿采空区地面塌陷的影响因素是采矿方法、煤层特征(厚度、产状和埋深)、顶板岩石力学性质、地表水和地下水综合作用的结果.采矿方法的改进和煤柱的留设与保护是防治塌陷的主要措施,监测工作是不可缺少的重要手段.  相似文献   

Variations in Melt Productivity and Melting Conditions along SWIR (70{degrees}E-49{degrees}E): Evidence from Olivine-hosted and Plagioclase-hosted Melt Inclusions   总被引：1，自引：0，他引：1  

Font  L.; Murton  B. J.; Roberts  S.; Tindle  A. G. 《Journal of Petrology》2007,48(8):1471-1494

Melt inclusion and host glass compositions from the easternend of the Southwest Indian Ridge show a progressive depletionin light rare earth elements (LREE), Na₈ and (La/Sm)_n, but anincrease in Fe₈, from the NE (64°E) towards the SW (49°E).These changes indicate an increase in the degree of mantle meltingtowards the SW and correlate with a shallowing of the ridgeaxial depth and increase in crustal thickness. In addition,LREE enrichment in both melt inclusions and host glasses fromthe NE end of the ridge are compatible with re-fertilizationof a depleted mantle source. The large compositional variations(e.g. P₂O₅ and K₂O) of the melt inclusions from the NE end ofthe ridge (64°E), coupled with low Fe₈ values, suggest thatmelts from the NE correspond to a variety of different batchesof melts generated at shallow levels in the mantle melting column.In contrast, the progressively more depleted compositions andhigher Fe₈ values of the olivine- and plagioclase-hosted meltinclusions at the SW end of the studied region (49°E), suggestthat these melt inclusions represent batches of melt generatedby higher degrees of melting at greater mean depths in the mantlemelting column. Systematic differences in Fe₈ values betweenthe plagioclase- and the olivine-hosted melt inclusions in theSW end (49°E) of the studied ridge area, suggest that theplagioclase-hosted melt inclusions represent final batches ofmelt generated at the top of the mantle melting column, whereasthe olivine-hosted melt inclusions correspond to melts generatedfrom less depleted, more fertile mantle at greater depths. KEY WORDS: basalt; melt inclusions; olivine; plagioclase; Southwest Indian Ridge  相似文献   

郭家岭岩体矿物包裹体研究     

王海芹  曲晓明  王鹤年 《山东国土资源》1998,(2)

通过对胶东金成矿区郭家岭岩体中熔融包裹体、含石盐子晶包裹体、ＣＯ２三相包裹体和Ｈ２Ｏ两相包裹体的显微测温,结果表明,该岩体在岩浆结晶晚期发生过高盐度流体与硅酸盐熔体的不混熔过程。根据熔融包裹体均一温度与均一过程的时间,利用相应公式,计算出郭家岭岩体包裹体熔体的粘度和含水量,认为该岩体是从一种高温高粘度的岩浆中结晶成岩的。  相似文献   

高压超高压变质作用中流体—熔体—岩石相互作用   总被引：2，自引：0，他引：2  

张泽明  韩郁菁 《地质科技情报》1998,17(3):24-30

在高压超高压变质作用过程中所释放的流体对俯冲板块的演化起着重要作用,与岛弧岩浆活动有着直接联系,随着温度和压力的增加,俯冲板片将发生高压到超高榴辉岩相转变,大量的水将通过含水矿物的消失反应释放出来,这些流体可引起上覆岩圈大规模水化,并促进地幔楔状体的部分熔融,同时,通过流体的向上迁移可将某些组分带入上覆岩石圈板块,并改变其总体组成,许多含水矿物,同变质脉体,高压自形晶体组成的布丁,原生液态包裹体和  相似文献   

上地幔熔体-岩石相互作用与大陆地幔演化   总被引：11，自引：2，他引：9  

徐义刚 《地学前缘》1998,(Z1)

根据实验岩石学、幔源岩石的岩石地球化学资料以及微量元素地球化学理论模拟等,评述了上地幔熔体岩石相互作用研究领域的最新进展,指出熔体岩石相互作用不仅深刻地制约了岩石圈地幔的矿物学、地球化学和物理性质的变化以及地幔不均一性的形成及演化,而且也会最终控制各种构造环境下喷出岩浆的地球化学特征,以及深部岩浆的分离机制。  相似文献   

Modelling observed and future runoff from a glacierized tropical catchment (Cordillera Blanca, Perú)   总被引：1，自引：1，他引：0  

Irmgard Juen  Georg Kaser  Christian Georges 《Global and Planetary Change》2007,59(1-4):37

Monthly runoff from the 34.3% glacierized tropical catchment of Llanganuco in the tropical Cordillera Blanca, Perú, is successfully simulated and compared with a measured 44 year time series. In the investigation area, the climate is characterized by all-year round homogenous temperature conditions and a strong variability in air humidity and moisture content of the atmosphere. Thus, contrary to the mid latitudes, the seasonal variation in glacier melt strongly depends on moisture-related variables, rather than on air temperature. The here presented ITGG-2.0-R model aims for these requirements. The lack of moisture-related input data other than precipitation demands for an intermediate calibration step. Net shortwave radiation, the emissivity of the atmosphere and a sublimation/melt ratio are related to precipitation amounts. Runoff is well simulated and correlates with the measured record with r² = 0.76. Seasonally obtained r² are only slightly smaller. On a long-term, the cumulative deviation is minor, and the mean annual cycle of runoff is reproduced rather well (r² = 0.99). Based on four different IPCC climate change scenarios, future runoff is simulated. All runoff scenarios are modelled for the respective steady-state glacier extent. This leads to a reduction in the glacier size and a decreased amount of glacier melt. On the other hand, direct runoff increases due to larger glacier free areas. Consequently, mean annual runoff remains almost unchanged, but the seasonality intensifies considerably with more runoff during the wet and less runoff during the dry season.  相似文献   

生物膜“细菌-藻类”协同系统改良淡水池塘养殖水质与沉积物的效果研究     

江兴龙  邓来富 《海洋与湖沼》2015,46(3):603-610

采用池塘中设置生物膜净水栅对比实验的方法,在8口土池开展生物膜"细菌-藻类"协同系统改良池塘养殖水质与沉积物的效果、对苗种培育效果的影响及其相关机理等的研究。结果表明,在142d的养殖期间,处理组比对照组节水减排达65.1%,具有极显著差异(P0.01);处理组水质的p H、总氮和亚硝酸盐氮分别极显著低于对照组3.7%、31.3%和38.7%(P0.01),氨氮、总磷、活性磷和硫化物分别显著低于对照组25.6%、41.6%、37.8%和27.9%(P0.05);弧菌数和藻类密度极显著低于对照组63.1%和51.3%,硅藻相对密度极显著高于对照组93.7%;细菌总数显著高于对照组50.8%,蓝藻相对密度显著低于对照组16.6%;处理组的藻类生物均匀度指数显著高于对照组8.9%;生物膜上的细菌总数高达1.30×109 CFU/g,而弧菌数为零;处理组池塘沉积物的氧化还原电位显著高于对照组30.5%,硫化物浓度显著低于对照组47.0%;草鱼苗种起捕规格、成活率、产量和生长速度分别显著高于对照组24.6%、4.3%、29.8%和28.6%,饲料系数极显著低于对照组15.6%,处理组每公顷池塘培育草鱼大规格鱼种可增加净利润约1.92万元。  相似文献   

海黍子(Sargassum muticum)池塘养殖及对氮磷去除效果的研究     

王翔宇  王志刚  吴海一 《海洋湖沼通报》2015,(1):91-95

初步研究了在海参养殖池塘中,不同养殖方式下,大型海藻海黍子(Sargassum muticum)的生长特性及对水体中氨氮和活性磷的去除作用。2012年3~5月,在山东莱州试验养殖海黍子60d,结果发现其长度最大从43.8cm增长到81.3cm,增长85.6%,日增长率(SGR)在14℃时最大,达到5.0%;每绳的平均质量从0.74kg增到2.59kg,增长3.5倍,SGR在12℃时最大,达4.3%;水体氨氮平均下降了25.9%,活性磷下降了37.5%。实验证明海黍子能在适合的池塘中养殖,并且能有效的去除水体中的氨氮和活性磷,是有效的近海生境修复大型工具种海藻。  相似文献   

软流圈熔体地幔交代作用过程中的铂族元素行为          下载免费PDF全文

王建  Keiko H.Hattori  Charles R.Stem  刘金霖 《地学前缘》2010,17(1):164

南美洲南部的Pali Aike火山岩区第四纪碱性玄武岩中普遍发育含石榴石的斜方辉石岩包体。这种斜方辉石岩既作为独立的捕掳体存在又以细脉的形式穿插于橄榄岩捕掳体中。斜方辉石岩普遍含富Ti矿物,并且次生斜方辉石含橄榄石和单斜辉石残晶。与含石榴石橄榄岩中的斜方辉石相比,这种次生的斜方辉石以高TiO2、中等含量的Al2O3以及低Mg#为特征,表明它是在一种高度分异演化的富Ti熔体交代作用下通过消耗橄榄石和单斜辉石方式形成的。斜方辉石岩全岩的Co、Ni略低,Cr和铂族元素(PGE)含量与地幔橄榄岩相当,表明这些元素在交代作用过程中相对稳定,而交代介质带入的组分以碱质(K2O+Na2O)、Ti、Si、Al和S为主。交代的斜方辉石在现代活动岛弧和古克拉通的地幔橄榄岩捕掳体中多有报道。与这些环境中地幔样品的斜方辉石相比,PaliAike地区的次生斜方辉石含有相对高的Ti和Al,以及相对低的Mg。高Ti低Mg属性反映了交代介质可能来源于下伏的软流圈地幔并且经历了高度的分异和演化过程。Pali Aike地区所见到的这种交代斜方辉石和斜方辉石岩在其他被上涌软流圈影响的陆下岩石圈地幔中可能普遍存在。这些研究对了解中国华北-东北中生代以来的岩石圈地幔减薄机制有着重要的借鉴意义。  相似文献   

Greenland Ice Sheet surface melt: A review     

Kang Yang  ManChun Li 《寒旱区科学》2014,6(2):0099-0106

Surface melt has great impacts on the Greenland Ice Sheet （GrlS） mass balance and thereby has become the focus of significant GrlS research in recent years. The production, transport, and release processes of surface meltwater are the keys to understanding the poten- tial impacts of the GrlS surface melt. These hydrological processes can elucidate the following scientific questions： How much melt- water is produced atop the GrlS？ What are the characteristics of the meltwater-formed supraglacial hydrological system？ How does the meltwater influence the GrlS motion？ The GrlS supraglacial hydrology has a number of key roles and yet continues to be poorly understood or documented. This paper summarizes the current understanding of the GrlS surface melt, emphasizing the three essential supraglacial hydrological processes： （1） meltwater production： surface melt modeling is an important approach to acquire surface melt information, and areas, depths, and volumes of supraglacial lakes extracted from remotely sensed imagery can also provide surface melt information; （2） meltwater transport： the spatial distributions of supraglacial lakes, supraglacial sarams, moulins, and crevasses demonstrate the characteristics of the supraglacial hydrological system, revealing the meltwater transport process; and （3） meltwater release： the release of meltwater into the englacial and the subglacial ice sheet has important but undetermined impacts on the GrlS motion. The correlation between surface runoff and the GrlS motion speed is employed to understand these influences.  相似文献