Comparison of surface air temperature derived from NCEP/DOE R2, ERA-Interim,and observations in the arid northwestern China: a consideration of altitude errors     

Shengjie Wang  Mingjun Zhang  Meiping Sun  Baolong Wang  Xiaoyan Huang  Qiong Wang  Fang Feng 《Theoretical and Applied Climatology》2015,119(1-2):99-111

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开源体系在GIS软件开发课程中的应用     

亢孟军  任福  蔡忠亮  翁敏  苏世亮  王明军 《测绘通报》2021,(5):145-150

商用GIS软件在GIS教学中的应用削弱了学生对原理和算法的认知和探索,有必要采用开源GIS体系进行代替。本文针对GIS软件开发系列课程的教学目标和知识点,对开源GIS软件体系进行了分类,并从许可协议、开发模式等方面提出了一套涉及GIS软件底层开发、桌面端开发、WebGIS开发和移动GIS开发的开源解决方案。通过教学实践证明,本文提出的开源解决方案能够显著提升学生的GIS软件开发技能。  相似文献   

Abe Barek landslide and landslide susceptibility assessment in Badakhshan Province,Afghanistan   总被引：2，自引：0，他引：2  

Jianqiang Zhang  Deo Raj Gurung  Rongkun Liu  Manchiraju Sri Ramachandra Murthy  Fenghuan Su 《Landslides》2015,12(3):597-609

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东海盆地西湖凹陷油岩地球化学特征及原油成因来源          下载免费PDF全文

苏奥  陈红汉 《地球科学》2015,40(6):1072-1082

东海盆地西湖凹陷具有大量的原油资源,但对于原油成因讨论较少.采集西湖凹陷多个油样和岩样,利用气相色谱和傅里叶红外光谱等手段,全面分析了该区烃源岩和原油的地球化学特征,综合讨论了原油来源以及凝析油和高蜡轻质油的成因.研究结果表明,平湖组煤系源岩均处于热演化的成熟阶段,其中碳质泥岩和煤岩以陆源生物为主要生源,其干酪根类型为Ⅲ型,暗色泥岩则具有陆源生物和水生生物双重生源贡献,其干酪根类型Ⅱ-Ⅲ型,同时碳质泥岩和煤的生油潜力远高于泥岩.原油主要为凝析油和轻质油,凝析油具有低密度、低蜡等“六低一高”的特点,轻质油具有高蜡特质,而且轻烃组分有明显差异.生标参数显示大部分原油为腐殖型,少部分原油表现出具有腐殖和腐泥母质的特点,同时该区原油均处于中等成熟阶段.油油对比和油岩对比表明大部分油来自平湖组碳质泥岩和煤岩,具有典型Ⅲ型腐殖油的特征;少部分油来自暗色泥岩,具有Ⅱ-Ⅲ型油的特征(总体上仍偏腐殖型).凝析油和轻质油的物性及轻烃组分的差异与源岩母质无关.凝析油是干酪根在成熟演化阶段生成的原油遭受蒸发分馏作用的结果,高蜡轻质油除了是“蒸发分馏作用”的残余油外,还有部分是“混合作用”的结果.   相似文献   

青海卡尔却卡铜多金属矿床地球化学特征与成矿物质来源          下载免费PDF全文

赖健清  黄敏  宋文彬  苏生顺  王守良 《地球科学》2015,40(1):1-16

为了解卡尔却卡铜多金属矿床的物质来源, 探讨其成岩、成矿机制, 通过现场调查, 结合矿床地质成矿条件, 对矿区典型的岩浆岩、围岩及矿石进行了主量元素、微量元素分析及S、Pb同位素分析.结果表明: 矿区岩体属中酸性岩, 为高钾钙碱性系列岩石, 源于深部, 上侵时受地壳混染, 具同源特征.不同地质体稀土配分曲线均为右倾轻稀土富集型, 岩浆岩、矽卡岩和矿石为同一成矿系统.微量元素地球化学显示矿区花岗岩产于火山弧环境.矿石硫同位素δ34S_CDT值为4.4×10-3~11.0×10-3, 处于岩浆硫跟围岩混合硫范围内, 成矿物质具多源性.矿石铅同位素Th/U值范围为3.46~3.69, μ值为9.46~9.52, 均低于9.58, 介于地壳与原始地幔值之间, 反应矿石铅具深源铅和壳源铅特征.铅同位素特征参数示踪、构造模式示踪和Δβ-Δγ图解示踪的结果表明: 铅来源与岩浆作用有关, 以壳源铅为主并混合少量深源地幔铅.总结矿床地球化学特征表明成矿物质主要来源于岩浆, 少量来源于周围地层.矿区岩体成矿演化过程复杂, 在岩体中形成斑岩型铜、钼矿化, 在与碳酸盐岩接触带形成矽卡岩型铅、锌矿化, 及至后期热液作用形成中低温热液脉型金矿化, 是一个多因复成矿床.   相似文献   

Dynamic changes in urban land spatial inequality under the core-periphery structure in urban agglomerations     

FANG Xiaoqian  SU Dan  WU Qing  WANG Jiayi  ZHANG Yangjian  LI Guoyu  CAO Yu 《地理学报(英文版)》2023,33(4):760-778

Relatively coordinated development among cities can typically promote the integration of the whole urban agglomeration, while urbanization of land has been found important to economic development in developing countries. Numerous studies have measured the urban land expansion in urban agglomerations. However, urban land spatial inequality under a specific spatial structure remains poorly understood. Here, we combined the β-convergence model and the core-periphery structure to explore the dynamic...  相似文献   

Light noble gases in 11 achondrites: Cosmic ray exposure ages,gas retention ages,and preatmospheric sizes     

Thomas Smith  Huaiyu He  Shijie Li  Fei Su 《Meteoritics & planetary science》2023,58(11):1580-1599

We report light noble gas (He, Ne, and Ar) concentrations and isotopic ratios in 11 achondrites, Tafassasset (unclassified primitive achondrite), Northwest Africa (NWA) 12934 (angrite), NWA 12573 (brachinite), Jiddat al Harasis (JaH) 809 (ureilite), NWA 11562 (ungrouped achondrite), four lodranites (NWA 11901, NWA 7474, NWA 6685, and NWA 6484), NWA 2871 (acapulcoite), and Sahara 02029 (winonaite), most of which have not been previously studied for noble gases. We discuss their noble gas isotopic composition, determine their cosmogenic nuclide content, and systematically calculate their cosmic ray exposure (CRE) and gas retention ages. In addition, we estimate their preatmospheric radii and preatmospheric masses based on the shielding parameter (²²Ne/²¹Ne)_cos. None of the studied meteorites shows evidence of contribution from solar cosmic rays (SCRs). JaH 809 and NWA 12934 show evidence of ³He diffusive losses of >90% and 40%, respectively. The winonaite Sahara 02029 has lost most of its noble gases, either during or before analysis. The average CRE age of Tafassasset of ~49 Ma is lower than that reported by Patzer et al. (2003), but is consistent with it within the uncertainties; this confirms that Tafassasset and CR chondrites are not source paired, CR chondrites having CRE ages from 1 to 25 Ma (Herzog & Caffee, 2014). The ureilite JaH 809 has a CRE age of ~5.4 Ma, which falls into the typical range of exposure ages for ureilites; the angrite NWA 12934 has a CRE age of ~49 Ma, which is within the main range of exposure ages reported for angrites (0.2–56 Ma). We calculate a CRE age of ~2.4 Ma for the brachinite NWA 12573, which falls into a possible “cluster” in the brachinite CRE age histogram around ~3 Ma. Three lodranites (NWA 11901, NWA 7474, and NWA 6685) have CRE ages higher than the average CRE ages of lodranites measured so far, NWA 11901 and NWA 6685 having CRE ages far higher than the CRE age already reported by Li et al. (2019) on NWA 8118. The measured ⁴⁰K-⁴⁰Ar gas retention ages fit well into established systematics. The gas retention age of Tafassasset is consistent, within respective uncertainties, with that previously calculated by Patzer et al. (2003). Our study indicates that Tafassasset originates from a meteoroid with a preatmospheric radius of ~20 cm, however discordant with the radius of ~85 cm inferred in a previous study (Patzer et al., 2003).  相似文献   

基于R/S分析的黑河出山年径流量灰色预测     

李建林  昝明军  李宝玲 《地域研究与开发》2014,(5)

径流过程具有分形和灰色特征。基于此,将R/S分析与灰色系统理论相结合,提出了R/S灰色预测模型以预报黑河出山径流量。针对1949—2011年莺落峡水文站年径流量资料,首先进行R/S分析,确定径流量序列的Hurst指数和平均循环周期T;然后在一个周期内进行径流量灰色预测。结果表明:黑河出山径流量循环周期在20~25年之间,在进行R/S灰色预测时,取T=20为宜;R/S灰色预测结果的精度高于直接进行灰色预测。该方法拓宽了分形和灰色理论在径流过程研究的应用范围,为径流量的科学预测提供了一种新方法。  相似文献   

历史文化名城名胜组景的时空演变特征研究——以金陵四十八景为例     

苏醒  张捷  张宏磊  钟士恩  陈星  李宜聪  李茹 《地域研究与开发》2014,(5)

名胜组景是一定地域范围内景观的组合,是历史文化名城的重要城市地标和旅游资源。以南京的金陵四十八景为例,研究名胜组景的时空演变特征。研究发现:金陵古代名胜组景依赖于自然地理环境,密集分布在长江、钟山、秦淮河等山脉和河流附近,同时也受人文地理界线的影响,较集中于南京城墙内;民国至当代的金陵四十八景的空间分布呈现东进南延北拓态势,逐步扩散至人文地理边界以外的外城郭,进而扩散到郊区县市(江北、高淳、溧水)。名胜组景的这种时空变迁特征与城市变迁存在强烈的关联。历史文化名城的组景景观可划分为自然景观和人文景观。金陵四十八景的时间演进过程中呈现自然景观数量减少、人文景观数量增多的趋势,景观景名、排序等存在较大的差异。古今游憩偏好的变化、旅游需求的变化、历史文化景观的积累、宗教变革、土地利用、社会职能的转变、时代文化的差异都对此产生一定程度的影响。  相似文献   

The use of GIS tools to support decision-making in the expansion of chain stores     

Rafael Suárez-Vega  Dolores R. Santos-Peñate 《International journal of geographical information science》2014,28(3):553-569

This article deals with a network competitive localization problem in which a firm seeks to determine the location of a new facility, which competes with all the facilities operating in the market, both belonging to the same firm and to the competing firms. In this context, two frequently conflicting objectives are involved: maximization of the total market share captured by the firm and minimization of market share losses for its existing facilities due to being captured by the new facility (cannibalization). We formulate the location problem as a multi-objective optimization model. Some GIS tools that provide some maps representing the market share and the cannibalization effect are proposed. This allows for the visualization of the effects produced by the opening of a new facility in the market and the trade-offs between the objectives. Finally, the advantages of using these tools have been shown by means of an application to a real data case.  相似文献