成矿作用的空间分布不均匀性及其控制因素探讨

全球矿产资源时空分布的不均匀性及其形成机制,已成为地球科学关注的热点和前沿领域。本文在对全球矿产资源的空间分布规律及其不均匀性分布特点的研究进展进行全面阐述的基础上,重点分析了控制成矿作用空间分布不均匀性的主要因素,如地壳组成与演化的差异、地壳/地幔化学组成的不均一性、成矿构造环境的差异、重大地质构造事件的影响、构造转换或转折和叠加、矿床形成与保存能力等。研究认为,深刻理解全球矿产资源空间分布的不均匀性特征及其形成的根本原因,应加强以下五个方面的研究:①大陆成矿作用的空间分布不均匀性的机制;②从全球构造角度,揭示成矿作用的时空分布规律;③强调深部成矿过程,以阐明成矿作用不均匀性原因;④加强成矿系统、成矿系列研究;⑤加强矿产资源时空分布不均匀性的形成机制研究。     

临南油田夏32断块沙二段下部储层特征及其主控因素

通过岩芯和薄片观察,结合测井资料,对临南油田夏32断块沙二段下部储层发育特征及其主控因素进行了研究。结果表明：该区储层的岩石类型主要为岩屑质长石砂岩和长石质岩屑砂岩,颗粒分选中等,磨圆较差,成分成熟度及结构成熟度中等;储层物性表现为中低孔特低—低渗的特征,且孔隙度和渗透率相关性较好;孔隙类型包括原生粒间孔、粒内溶孔、粒间溶孔和铸模孔。综合储层特征的研究结果认为：夏32断块沙二段下部储层主要受基准面旋回、沉积、成岩以及构造作用的影响;三角洲平原的分支河道砂体物性最好,其次是三角洲前缘的水下分支河道,其他沉积微相储层物性较差;压实作用和胶结作用破坏储层物性,溶蚀作用则可改善储层物性;此外,构造作用所产生的裂隙也有利于改善储层物性,对储层物性起到了积极的建设作用。     

河北沧县台拱带中、低温地热资源ORC发电与综合梯级利用

京津冀地热资源梯级综合开发利用(献县)科研基地大地构造位置位于华北平原沧县台拱带之献县断凸,利用其地下蓟县系岩溶裂隙热储层热水开展中低温地热发电与综合梯级利用研究。地热发电装机容量280 kW,采用ORC向心透平膨胀技术,系统工质为R245fa。分别于2018年2月4—6日(冬季)、2018年3月6—16日(春季)进行两次试运行,累计发电时长274h,累计发电量36956kWh,平均发电效率9.1%,最高10.4%。发电效率高于我国已有中低温地热发电项目,在目前国际中低温ORC地热发电项目中处于较高水平。试运行期间发电机组整体运行效果较好且运行稳定,冬季地热发电机组运行效果好于春季。科研基地建设完成后,将进行发电、供暖、地热生态园三级利用,按照90～95/25℃的地热水热能潜力,综合发电供暖两级利用计算能源综合利用率将达70%～76%。     

高速公路缓倾红层软岩滑坡形成机制及防治措施研究

以缓倾红层软岩地区某新建高速公路路堑开挖滑坡为例,通过对该滑坡形成过程、致灾因素及变形机制进行分析,结果表明:前缘开挖临空条件、大气降雨是滑坡产生的主要因素,高边坡开挖形成临空面,降雨使岩体处于饱水状态,在裂缝扩张力及静水压力作用下,形成垂直裂隙并向岩体深部发展,剪断岩层局部层面结构面,最后贯通形成滑面滑动致灾。滑坡前缘反压堆载、后缘裂缝遮盖防雨,坡面截排水、位移监控等应急措施止滑效果较好,推荐采用支挡工程+清方方案处治滑坡。建议缓倾红层软岩边坡加固设计贯彻分级支挡思路,以提高边坡稳定性及施工安全性。     

川藏公路藏东段边坡稳定性研究与治理评价

川藏公路是一带一路南亚通道的主要干线,其藏东段地质灾害频发,如何有效治理、保障安全畅通意义重大。文章在详细调查的基础上,对取得的藏东段沿线所有边坡数据进行统计及特征分析,利用随机森林理论建立了边坡稳定性评判模型,根据计算出的影响因素重要性大小对边坡的稳定性进行判别,模型检验表明其准确率超过94.44%,同时结合实地验证,对边坡的治理提出了可行性建议,为川藏公路藏东段的有效治理提供实用参考资料。      

Watershed-scale vegetation,water quantity,and water quality responses to wildfire in the southern Appalachian mountain region,United States

Wildfires are landscape scale disturbances that can significantly affect hydrologic processes such as runoff generation and sediment and nutrient transport to streams. In Fall 2016, multiple large drought-related wildfires burned forests across the southern Appalachian Mountains. Immediately after the fires, we identified and instrumented eight 28.4–344 ha watersheds (four burned and four unburned) to measure vegetation, soil, water quantity, and water quality responses over the following two years. Within burned watersheds, plots varied in burn severity with up to 100% tree mortality and soil O-horizon loss. Watershed scale high burn severity extent ranged from 5% to 65% of total watershed area. Water quantity and quality responses among burned watersheds were closely related to the high burn severity extent. Total water yield (Q) was up to 39% greater in burned watersheds than unburned reference watersheds. Total suspended solids (TSS) concentration during storm events were up to 168 times greater in samples collected from the most severely burned watershed than from a corresponding unburned reference watershed, suggesting that there was elevated risk of localized erosion and sedimentation of streams. NO₃-N concentration, export, and concentration dependence on streamflow were greater in burned watersheds and increased with increasing high burn severity extent. Mean NO₃-N concentration in the most severely burned watershed increased from 0.087 mg L⁻¹ in the first year to 0.363 mg L⁻¹ (+317%) in the second year. These results suggest that the 2016 wildfires degraded forest condition, increased Q, and had negative effects on water quality particularly during storm events.     

基于多源数据的新疆人居环境质量评价

针对区域人居环境质量缺乏从自然和人文因子组合综合评价分析的现状,利用遥感影像、站点监测、交通网络等多源数据,获取与人居环境质量密切相关的自然和人文因素共17个影响因子。应用熵权法、GIS空间分析及现代大数据等方法,定量研究新疆人居环境质量综合评价指数的空间分异及其与经济、人口分布的协调性关系。结果表明：① 新疆自然环境本底受水资源及植被覆盖情况影响较大,自然环境本底评价指数高值区域的空间分布特征与绿洲分散分布的特点具有极大的相似性,县域尺度的高质量区聚集分布在天山北坡的伊犁河谷等地,低质量区和一般质量区大面积集中连片地分布在新疆南部和东部。② 人文环境受交通通达程度及基础支撑完善度影响较大,地级市、县级市优于其他县级地区,人文环境质量基本呈现以各地级市、县级市为中心向外辐射递减的空间分异规律。③ 人居环境质量综合评价指数空间分异显著,呈现出以乌鲁木齐、昌吉市等点为中心的局部圈层式递减的空间分异规律。木垒?皮山分界线东南部与西北部人居环境质量的平均水平相差悬殊。④ 整体人居环境质量水平较低,人口分布与人居环境质量综合评价指数空间分布的匹配度不足,一般质量区和低质量区的县域土地面积占比高达84.90%,分布了47.74%的人口,低质量区仍有较大的提升潜力。⑤ GDP水平与人居环境质量保持较高的匹配性,环境经济协调型县市数量较少,环境经济滞后型县市数量最多,经济发展与人居环境相互掣肘,制约着新疆的可持续性发展。     

天然气水合物开采储层出砂研究进展与思考

天然气水合物开采井眼出砂问题是当前水合物产业化急需突破的瓶颈之一,解决水合物开采时防砂与产能平衡问题是实现水合物安全高效、长期可控开采的关键.我国海域典型水合物储层属于弱固结的低渗泥质粉砂储层,其面临的防砂控泥与增产矛盾较为突出.厘清不同水合物储层和开采条件下的井眼出砂规律并揭示其机理,进而制定科学合理的防砂控泥措施以实现产能最大化是解决上述矛盾的途径所在.从理论分析、数值模拟、室内实验和现场试采4个角度介绍了世界范围内已开展的水合物出砂防砂情况,分析总结了水合物储层出砂影响因素及出砂机理,最后探讨了目前出砂研究存在的问题和挑战,并给出了相应的建议,旨在为后续水合物开采井眼出砂预测和防控研究提供思路和参考.     

Control factors of DIC in the Y3 seamount waters of the Western Pacific Ocean

An investigation was carried out in the Y3 seamount area of the Western Pacific Ocean in December 2014,and the distribution of dissolved inorganic carbon(DIC) and its relationship with environmental factors in this area were explored.The results show that DIC concentration was higher in the adjacent waters of the Y3 seamount area,and the uplift of DIC isolines at the stations was close to the seamount.Meanwhile,interaction between the North Equatorial Current(NEC) and the Y3 seamount affected the DIC distribution i.e.,the upwelling in the same direction of the NEC was obvious,resulting in a decreasing trend of average concentration of DIC in the 200 m water column from the top to the two side s in this direction but in the cross direction.The DIC concentration increased with the water depth increase,and its distribution was affected by various environmental factors.In the surface water,high temperature was a decisive factor for the decrease of the DIC concentration,but the photosynthesis of phytoplankton showing only a weak influence.In the North Pacific Tropic Water(NPTW),DIC production rate from organic matter decomposition was higher than that of DIC consumption by phytoplankton photosynthesis,leading to a continual increase of DIC.In the North Pacific Intermediate Water(NPIW),organic matter decomposition played a leading role in the increase of DIC.In the deep water,decomposition of organic matter weakened,and the dissolution of CaCO_3 controlled the carbonate system,and DIC had the smallest variation range.     

基于RESTful API的智慧旅游系统设计与实现

从系统的扩展性、耦合性和可用性出发,在深入研究RESTful API的基础上,结合智慧旅游的特点,提出了基于RESTful API的智慧旅游系统建设方案。设计了基于RESTful API的智慧旅游框架,制定了RESTful API设计的基本原则,并从资源标识、参数、资源的表述、验证、异常处理和缓存6个方面分别介绍智慧旅游API的设计方法。最后,通过具体的实例证明了该方法可提高智慧旅游系统的扩展性、耦合性和可用性,为智慧旅游系统设计提供了一种可行的方案。