The upper Bathonian Ammonites first found in North Siberia

The upper Bathonian Ammonites Cadoceras perrarum Voron. and Kepplerites ex gr. rosenkrantzi Spath are reported for the first time from the western coast of Anabar Bay, loosely collected. Both ammonoids represent index species of two biostratigraphic units: the Cadoceras barnstoni Beds and Cadoceras variabile Zone. The occurrence of genus Kepplerites (Kosmoceratidae) in North Siberia is evidence in favor of the migration of that family into the seas of the Arctic region.     

Effects of Enclosure on Plant and Soil Nutrients in Different Types of Alpine Grassland

Enclosure is one of the most widely used management tools for degraded alpine grassland on the northern Tibetan Plateau, but the responses of different types of grassland to enclosure may vary, and research on these responses can provide a scientific basis for improving ecological conservation. This study took one site for each of three grassland types (alpine meadow, alpine steppe and alpine desert) on the northern Tibetan Plateau as examples, and explored the effects of enclosure on plant and soil nutrients by comparing differences in plant community biomass, leaf-soil nutrient content and their stoichiometry between samples from inside and outside the fence. The results showed that enclosure can significantly increase all aboveground biomass in these three grassland types, but it only increased the 10-20 cm underground biomass in the alpine desert. Enclosure also significantly increased the leaf nutrient content of the dominant plants and contents of total nitrogen (N), total potassium (K), and organic carbon (C) in 10-20 cm soil in alpine desert, thus changing the stoichiometry between C, N and P (phosphorus). However, enclosure significantly increased only the N content of dominant plant leaves in alpine steppe, while other nutrients and stoichiometries of both plant leaves and soil did not show significant differences in alpine meadow and alpine steppe. These results suggested that enclosure has differential effects on these three types of alpine grasslands on the northern Tibetan Plateau, and the alpine desert showed the most active ecological conservation in the responses of its soil and plant nutrients.     

Numerical simulation on mining-induced water inrushes related to geologic structures using a damage-based hydromechanical model

A large number of statistics indicate that water inrush has a direct relationship with geological structures such as fault and karst collapse columns. Understanding the mechanism of water inrushes controlled by geologic structures is of vital importance for adopting effective measures to prevent their occurrence. The work begins with formulization of a damage-based hydromechanical model based on elastic damage theory. Next, the model is numerically implemented with finite element method by employing a finite element package called COMSOL Multiphysics, and is also validated against some existing experimental observations. Finally, the model is used to simulate the mining-induced groundwater inrushes when the effect of faults and karst collapse columns is considered in the numerical simulation, and some suggestive conclusions for preventing water inrushes and optimizing underground mining operations are drawn.     

Impacts and adaptation to climate change in European economies

This paper evaluates the impacts of climate change to European economies under an increase in global mean temperature at +2 °C and +4 °C. It is based on a summary of conclusions from available studies of how climate change may affect various sectors of the economies in different countries. We apply a macroeconomic general equilibrium model, which integrates impacts of climate change on different activities of the economies. Agents adapt by responding to the changes in market conditions following the climatic changes, thus bringing consistency between economic behaviour and adaptation to climate change. Europe is divided into 85 sub-regions in order to capture climate variability and variations in vulnerabilities within countries. We find that the impacts in the +2 °C are moderate throughout Europe, with positive impacts on GDP in some sub-regions and negative impacts down to 0.1 per cent per year in others. At +4 °C, GDP is negatively affected throughout Europe, and most substantially in the southern parts, where it falls by up to 0.7 per cent per year in some sub-regions. We also find that climate change causes differentiations in wages across Europe, which may cause migration from southern parts of Europe to northern parts, especially to the Nordic countries.     

顾及形态特征和语义信息的双线道路识别方法

双线道路识别与提取是城市路网综合的关键。提出了一种城市双线道路提取的方法。在构建好的道路网眼的基础上,综合考虑双线道路网眼形态特征以及构成网眼路段之间的语义相似度,设计了识别双线道路网眼的综合指标。通过判断网眼综合指标确定最终的双线道路网眼,最后根据识别出的双线道路网眼提取出双线道路。实验表明,该方法能有效提取出城市道路数据中的双线道路。     

迁移学习支持下的高分影像山地滑坡灾害解译模型

无人机低空遥感是近年来新兴的一种快速获取灾情信息的手段,如何利用无人机高分影像构建滑坡灾害解译模型是实现快速自动解译滑坡的关键。针对该问题,对比了多种影像特征提取方法,将迁移学习(TL)特征和支持向量机(SVM)引入到构建滑坡灾害自动解译模型中,提出了一种TL支持下的高分影像滑坡灾害解译模型。选取5·12汶川地震及4·20芦山地震系列无人机影像构建了滑坡灾害样本库并进行了实验,TL特征方法整体分类准确度ACC为95%,ROC达到0.98,识别准确率达到97%。结果表明,所提方法可用于高分影像滑坡自动解译,同时可用于大面积高分影像中快速山地滑坡灾害定位及检测。     

高光谱影像概率分类向量机分类方法研究

从分析基于支持向量机和相关向量机的高光谱影像分类方法的优势和不足出发,将基于概率分类向量机的方法用于高光谱影像分类试验。在贝叶斯理论框架下,概率分类向量机为基函数权值引入截断Gauss先验概率分布,使得不同类别的基函数权值具有不同符号的先验分布,并利用EM算法进行参数推断,得到足够稀疏的概率模型,弥补了相关向量机选取错误类别的样本作为相关向量的不足,从而有效地提高了模型的分类精度和稳定性。OMIS和PHI影像分类试验表明,概率分类向量机能够很好地应用在高光谱影像分类。     

内蒙古黄花滩铜镍矿区辉长岩LA-ICP-MS锆石U-Pb定年及地球化学特征

在乌拉特后旗—达茂旗—四子王旗一带的内蒙古中部地区分布着超基性-酸性连续岩浆系列,开展其岩体年代学、地球化学研究可为内蒙古中部地区与超基性-基性岩有关的铜镍矿成矿规律研究提供基础地质资料,还可以推断岩浆侵位时期的区域大地构造背景。本文以达茂旗黄花滩铜镍矿区出露的辉长岩为研究对象,采用LA-ICP-MS仪器对无裂隙、高透明度、阴极发光均匀、环带清晰的锆石进行U-Pb定年,获得岩体加权平均年龄为262.4±1.1 Ma,并利用XRF和ICP-MS进行岩石地球化学分析显示黄花滩辉长岩具有后碰撞拉伸环境下的岩浆特征。综合前人相关研究认为,内蒙古中部地区于中二叠世晚期(255~275 Ma)已经进入后碰撞构造阶段,而古亚洲洋在该区域的闭合应发生在晚二叠世前(~285 Ma),此结论丰富了古亚洲洋闭合时间上限及中晚二叠世期间内蒙古中部地区构造背景方面的证据。     

便携式Li-K分析仪的研制及其在锂辉石中锂的分析应用

我国锂钾主要矿产资源大多分布在西部偏远地区,其勘查找矿或综合利用迫切需要现场快速分析技术的支持。本文介绍了自行开发的便携式Li-K分析仪的主要性能及其在锂辉石中锂的分析应用。Li-K分析仪是一种基于大气压的液体阴极辉光放电光谱仪,以待测液体为放电阴极,实现了样品中Li、K等元素的原子化和激发。该仪器以光纤传导CCD光谱仪作为检测器,其波长范围为345~1015 nm,分辨率3 nm;以Li 670.78 nm和K 769.90 nm分析谱线,在仪器最佳工作条件下测定Li、K的精密度(RSD,n=14)均低于2%,检出限为0.03μg/m L,检测范围0.1~10μg/m L。研究表明,不同酸度和酸的类型对谱线强度影响较大,且存在显著的样品基体效应,标准曲线法分析锂辉石中Li的结果偏差高达267%;而标准加入法可克服基体效应的影响,获得与ICP-OES一致性较好的分析结果,为现场开展固体样品中Li的测定奠定了基础。     

丝绸之路经济带甘肃黄金段找矿勘查新进展

丝绸之路经济带已成为国家战略,赋于了上合组织新的内涵,也给地质工作者提出了新的要求。甘肃是古丝绸之路的锁匙之地,是丝绸之路经济带上的“黄金路段”。2014年甘肃省提出利用拥有古丝绸之路贯穿境内1600 km的战略通道优势,打造丝绸之路经济带的黄金段,使其成为向西开放的战略平台、经贸物流的区域中心、产业合作的示范基地、人才交流的桥梁纽带。本文就甘肃省矿产资源优势、找矿勘查新进展及向西走出去提出建议。