The project “spice”     

D. Rouan  N. Epchtein  M. De Muizon  F. Lacombe  P. Puget  D. Tiphene  F. Boulanger  X. Desert  G. Guyot  L. D'Hendecourt  J -M. Lamarre  A. Leger  F. Pajot  J -L. Puget  E. Caux  M. Giard  G. Serra  C. Cesarsky  L. Vigroux  A. Omont 《Astrophysics and Space Science》1994,217(1-2):41-44

Proposed to both the French and the European Space Agency as one possible small mission, SPICE is a project for a dedicated small satellite for a near-IR spectroscopic all-sky survey. The instrument would cover the spectral range 1.8 - 3.6µm, possibly extended to 1.8 - 7µm, at a resolution of 100, with pixels of 1 arc-min. The excellent sensitivity (0.02 MJy sr-1) results from: i) the quasi-zero level of background due to the efficient passive cooling of the whole experiment; ii) the use of large format arrays; iii) the non-stop observing mode (drift-scanning). The spectral domain, complementing the one of ISO, partially opaque from the ground, is specially rich in spectral features tracing stars and all components of the Interstellar Medium (molecular, atomic and ionized gas, dust). With a cooling below 80 K of the focal instrument, then it becomes possible to consider doubling the spectral domain and to cover the whole 1.8 - 7µm range.  相似文献   

Probabilistic seismic hazard evaluation in underground mines     

Ewa GłOwacka 《Natural Hazards》1993,7(2):121-132

Stress concentrations produced by rock deformation due to extraction in underground mines induce seismicity that can take the shape of violent and quite dangerous rockbursts.The hazard evaluation presented in this paper is based on a Bayesian probabilistic synthesis of information determined from mining situations during excavation, with previous and present data from microseismicity and seismoacustics.The method proposed in this study is an example of time-dependent on-line seismic hazard evaluation. All results presented were obtained retrospectiely for different underground coal mines in Poland and Czechoslovakia.On leave from Institute of Geophysics, Polish Academy of Sciences 01-452 Warszawa, ul. Ksiecia Janusza 64, Poland.  相似文献   

山东省日照市蓝色经济区工程建设适宜性评价     

朱伟  李玲  杨鹏  杨崇敬  艾洪键 《地球学报》2024,45(1):112-122

本文以山东省日照市蓝色经济区为研究区, 通过野外地质调查和室内综合分析, 选取场地稳定性、工程地质条件、地下水条件, 地形排水条件、地质灾害及其他因素6个一级评价因子, 构造活动、场地土类型、建筑场地类别等13个二级评价因子, 利用专家-层次分析定权法进行区内工程建设适宜性评价, 得到了相应工程建设评价分区图。评价结果表明, 日照市场地工程建设适宜性总体较好, 大部分地区适宜进行高层建筑工程建设, 占84.50%; 地下空间开发利用条件优越, 全区多数地区属于城市地下空间建设适宜区, 适宜性差及不适宜区主要分布在付疃河两岸附近和海岸附近、大型高速公路和铁路沿线一带区域及城区; 轨道交通建设适宜性良好, 小部分不适宜区主要集中在付疃河下游夹仓和小古镇一带及其沿海地区。评价结果可有效地服务于该地区规划布局、建设发展和工程选址, 具有重要的理论和实践指导意义。  相似文献   

河北省唐山地区丰台—野鸡坨断裂第四纪活动性——来自¹⁴C和磁性地层年代学的证据          下载免费PDF全文

陈宏强  专少鹏  陈超  赵华平  杨瑞  何娇月  胥勤勉 《中国地质》2021,48(2):605-617

丰台—野鸡坨断裂为唐山地区主要断裂之一，西侧为鸦鸿桥凹陷，东侧为唐山凸起，断裂两侧第四系厚度之差巨大。本文依据该断层两侧钻孔对其第四纪以来活动性进行初步的探讨。通过对丰台—野鸡坨断裂上下两盘PZK14和PZK20孔磁性地层学研究，并结合钻孔岩石地层，及浅部光释光和¹⁴C测年结果，建立第四纪地层格架。结果表明：两孔底部“泥包砾”为新近纪沉积；PZK14孔下更新统底界埋深为387 m，中更新统底界埋深为114 m，上更新统底界埋深为71 m，全新统底界埋深为6 m；PZK20孔下更新统底界埋深为155 m，中更新统底界埋深为73 m，上更新统底界为36 m，无全新世地层。丰台—野鸡坨断裂活动在早更新世时表现为逐渐增强的特点，活动速率由早期的5.4 cm/ka增加到13.9 cm/ka。中更新世断裂活动基本处于停滞状态，活动速率为1.0 cm/ka。晚更新世以后，断裂重新活动，且更加剧烈，活动速率达到了54.5 cm/ka。  相似文献   

雄安新区地热地质模型探究：来自地球物理的证据          下载免费PDF全文

王凯  张杰  白大为  吴新刚  岳航羽  张保卫  王小江  张凯 《中国地质》2021,48(5):1453-1468

雄安新区内地热资源丰富，区内有牛驼镇地热田、容城地热田和高阳地热田，地热资源开发利用较早，但是对其深部热源机制仍未形成统一观点。为了研究雄安新区内地热田深部热源机制，在新区及外围进行了深反射地震和长周期大地电磁探测，对取得的同剖面的深反射地震和大地电磁数据进行处理和综合解释，探明了研究区从地表至莫霍面范围内地质构造和电性结构。下地壳结构在深反射地震剖面与大地电磁剖面上有很好的对应关系。电阻率低值区对应着在深反射地震剖面上存在一系列反射同相轴，且同相轴可以延续到莫霍面，电阻率高值区对应着在深反射地震剖面上无明显连续反射同相轴，尤其是在莫霍面之上呈现地震反射近似"空白区"。结合区域地热资料构建了研究区深部地热地质模型，对新区内深部地热机制进行了解释。该模型为"二元"生热模型，其热源包含两个部分，深部地幔热源和地壳放射性元素衰变生热。放射性元素衰变生热占地表热流的接近30%，而幔源热流在地表热流中的占比可达约70%。在牛驼镇下方，莫霍面以上，由于地幔热物质上涌造成下地壳上隆，幔源岩浆底侵作用于下地壳形成了局部热异常，该热异常具有低速高导的地球物理特征，认为是牛驼镇地热田和容城地热田的深部热源；以区域断裂为热通道，大地热流由深部向上传导、扩散到牛驼镇凸起和容城凸起顶部，对碳酸盐岩储水层进行加热，形成地热储层；上覆新近系沉积地层是良好的热盖层。  相似文献   

碳中和目标下关键矿产在清洁能源转型中的作用、供需分析及其建议          下载免费PDF全文

王欢  马冰  贾凌霄  于洋  胡嘉修  王为 《中国地质》2021,48(6):1720-1733

在"碳中和"目标的驱动下，全球能源系统向清洁化、低碳化甚至无碳化发展已是大势所趋。针对向清洁能源转型的需求，采用了统计对比、分类汇总、综合分析等方法，分析研究了关键矿产在电池、电网、低碳发电和氢能等行业中的作用和需求。结合当前关键矿产产量的地理集中度高、项目开发周期长、资源质量下降等矿产供应和投资计划不能满足清洁能源转型的需求等问题，提出确保关键矿产多样性供应，推动价值链各环节的技术创新，扩大回收利用，增强供应链弹性和市场透明度，将更高的环境、社会和治理标准纳入主流程及加强生产者和消费者之间的国际合作等建议。  相似文献   

快速城镇化进程中珠江三角洲高铵地下水赋存环境及驱动因素          下载免费PDF全文

吕晓立  刘景涛  韩占涛  朱亮  杨明楠  李海军 《中国地质》2021,48(6):1770-1780

地下水中高浓度的铵态氮对生活饮用水安全及生态环境存在潜在威胁。相比较硝态氮，高浓度的铵态氮不仅有各种人为来源，天然沉积环境更是造成高铵地下水的主要成因。本文以城镇化快速发展的珠江三角洲为研究区，运用数理统计、主成分分析等方法深入探讨了研究区高铵地下水的赋存环境特征及驱动因素。结果表明，研究区地下水中NH₄⁺质量浓度介于未检出~180 mg/L。研究区1539组地下水样品中，NH₄⁺质量浓度大于10 mg/L的高铵地下水69组，其中含NH₄⁺质量浓度大于30 mg/L的高铵"肥水"23组。对比2005-2008年历史水化学数据，2009-2018年新增建设用地孔隙含水层高铵地下水样品比例增加25%。高铵地下水呈斑块状分布于三角洲平原区第四系底部低洼的基底、洼地等退积层序发育的淤泥质含水层中。淤泥层等富含有机质和总有机碳的沉积层是珠江三角洲地区的"生铵层"，有机氮的矿化是三角洲平原区城市化孔隙含水层中高铵地下水的主要驱动力。城镇化扩张引起生活污水及富铵工业废水的泄漏入渗是城乡结合部高铵地下水铵氮的重要来源。三角洲平原区中性至弱碱性富含有机质的还原环境是高铵地下水的主要成因。风化溶滤、阳离子交换吸附、海陆交互作用是珠江三角洲高铵地下水质演变的主要水文地球化学过程。  相似文献   

Environmental geology problems in the Tyrrhenian coastal area of Santa Marinella, province of Rome, central Italy   总被引：1，自引：0，他引：1  

U. Chiocchini  G. Gisotti  A. Macioce  F. Manna  A. Bolasco  C. Lucarini  G. M. Patrizi 《Environmental Geology》1997,32(1):1-8

 The Tyrrhenian resort of S. Marinella (central Italy) is subjected to significant anthropogenic pressures during the summer vacation period, a common situation all along the Italian coast. Located 65 km NW of Rome on the southern slopes of the Tolfa Mountains, S. Marinella is built on a gently sloping, E–W trending belt which is cut by 14 N–S oriented ephemeral streams that discharge into the Tyrrhenian Sea. The low to medium permeability turbiditic sandstones which outcrop along this belt belong to the Late Cretaceous Pietraforte unit. Three environmental problems are addressed in this study. The first problem is related to the high water supply demand during the summer months which has forced local residents to dig a large number of wells. Extensive pumping from these wells has caused salt-water intrusion into the Pietraforte, thus compromising the domestic use of the groundwater. The second problem consists of the illegal dumping of urban solid waste, material that represents a hazard during significant rain events as well as a possible cause of groundwater contamination. The final issue addressed concerns the flooding potential of the 14 ephemeral streams that cross the inhabited area of S. Marinella, a risk which is highlighted by the disastrous flood which occurred on 2 October 1981 and during the period of the Roman Emperor Settimio Severo (205 A.D.). Some suggestions are proposed to mitigate and contain the effects of these problems. Received: 7 November 1995 / Accepted: 5 December 1996  相似文献   

Probabilistic seismic hazard zonation of Syria     

Abdallah I. Husein Malkawi  Robert Y. Liang  Jamal H. Nusairat  Azm S. Al-Homoud 《Natural Hazards》1995,12(2):139-151

Earthquake hazard maps for Syria are presented in this paper. The Peak Ground Acceleration (PGA) and the Modified Mercalli Intensity (MMI) on bedrock, both with 90% probability of not being exceeded during a life time of 50, 100 and 200 years, respectively are developed. The probabilistic PGA and MMI values are evaluated assuming linear sources (faults) as potential sources of future earthquakes. A new attenuation relationship for this region is developed. Ten distinctive faults of potential earthquakes are identified in and around Syria. The pertinent parameters of each fault, such as theb-parameter in the Gutenberg-Richter formula, the annual rate ₄ and the upper bound magnitudem ₁ are determined from two sets of seismic data: the historical earthquakes and the instrumentally recorded earthquake data (AD 1900–1992). The seismic hazard maps developed are intended for preliminary analysis of new designs and seismic check of existing civil engineering structures.  相似文献   

Comparison of two methods for seismic hazard assessment in a low-seismicity area     

Th. De Crook  J. J. Egozcue 《Natural Hazards》1992,6(1):39-49

The EGO method, developed by Egozcue et al. and the SRAMSC method, originally developed by Cornell and later programmed by McGuire, to assess the seismic hazard, are compared for the low seismicity area Belgium, The Netherlands, and NW Germany. Using the same input data, the results of the EGO method without the majority criterion and the SRAMSC method with upper bound XII agree very well. The influence of the zoning is investigated for the EGO method. It is not necessary to define the zones for the EGO method so strictly as for the SRAMSC method, but too wide zones can give bad results.  相似文献