Ages of sediment-hosted Himalayan Pb–Zn–Cu–Ag polymetallic deposits in the Lanping basin,China: Re–Os geochronology of molybdenite and Sm–Nd dating of calcite

The Lanping basin is a significant Pb–Zn–Cu–Ag mineralization belt of the Sanjiang Tethyan metallogenic province in China. Over 100 thrust-controlled, sediment-hosted, Himalayan base metal deposits have been discovered in this basin, including the largest sandstone-hosted Pb–Zn deposit in the world (Jinding), and several Cu ± Ag ± Co deposits (Baiyangping, Baiyangchang and Jinman). These deposits, with total reserves of over 16.0 Mt Pb + Zn, 0.6 Mt Cu, and 7000 t Ag, are mainly hosted in Meso-Cenozoic mottled clastic rocks, and strictly controlled by two Cenozoic thrust systems developed in the western and eastern segments of the Lanping basin.To define the metallogenic history of the study area, we dated nine calcite samples associated with copper sulfides from the Jinman Cu deposit by the Sm–Nd method and five molybdenite samples from the Liancheng Cu–Mo deposit by the Re–Os method. The calcite Sm–Nd age for the Jinman deposit (58 ± 5 Ma) and the molybdenite Re–Os age for the Liancheng deposit (48 ± 2 Ma), together with previously published chronological data, demonstrate (1) the Cu–Ag mineralization in the western Lanping basin mainly occurred in three episodes (i.e., ∼56–54, 51–48, and 31–29 Ma), corresponding to the main- and late-collisional stages of the Indo–Asian orogeny; and (2) the Pb–Zn–Ag (±Cu) mineralization in the eastern Lanping basin lacked precise and direct dating, however, the apatite fission track ages of several representative deposits (21 ± 4 Ma to 32 ± 5 Ma) may offer some constraints on the mineralization age.     

电离层E_S层对综合射束污染的初步分析

本文考虑到干涉仪对电离层中不同尺度不规则性的滤波作用、结合密云米波综合孔径系统、提出了电离层E_(?)层是电离层不规则性影响该系统的主要根源。不规则性的尺度约在700～1000米的范围。再考虑到E_(?)层的漂移运动,提出了文中所描述的模型。用电子计算机进行了E_(?)层对综合射束污染的模拟计算,结果指出:射束主瓣的增益下降约10％,副瓣由13％增大到18％;综合射束在赤经方向出现不对称性,从而引起约0.6秒的赤经误差;射束的边缘处和两个扇形区出现了杂瓣。     

Application of an improved semi-Lagrangian procedure to fully-nonlinear simulation of sloshing in non-wall-sided tanks

The semi-Lagrangian procedure is widely used for updating the fully-nonlinear free surface in the time domain. However, this procedure is only available to cases when the body surface is vertical near the waterline. Present study introduces an improved semi-Lagrangian procedure which removes this ‘vertical-wall’ limitation. Coupling with the boundary element method, the improved semi-Lagrangian procedure is applied to the simulation of fully-nonlinear sloshing waves in non-wall-sided tanks. From the result comparison with the open source CFD software OpenFOAM, it is confirmed that this numerical scheme could guarantee a sufficient accuracy. Further series studies on 2D and 3D fully-nonlinear sloshing waves in wedged tanks are performed. Featured phenomena are observed which are distinct from those in wall-sided tanks.     

Diagenetic evolution of the upper Cretaceous limestone and sandstone exhumed reservoirs in the western Basque–Cantabrian Basin,North Spain

The Basque–Cantabrian Basin (NE Spain) has been considered one of the most interesting areas for hydrocarbon exploration in the Iberian Peninsula since the 60th to 70th of last century. This basin is characterized by the presence of numerous outcrops of tar sands closely associated with fractures and Triassic diapirs. The aims of this work is to establish the diagenetic evolution of the Upper Cretaceous reservoir rocks with special emphasis in the emplacement of oil and their impact on reservoir quality. The studied rocks are constituted of carbonates and sandstones that contain massive quantities of bitumen filling vugs and fractures.Petrographic results indicate that the carbonate rocks from Maestu outcrops are bioclastic grainstones and wackestones, whereas the tar sandstones from Atauri and Loza outcrops are dominated by quartzarenites and subordinated subarkoses. The paragenetic sequence of the main diagenetic phases and processes include, pyrite, bladed and drusy calcite cement, calcite overgrowths, silicification of bioclasts and microcrystalline rhombic dolomite cement, and first stage of oil emplacement, blocky calcite cement, coarse crystalline calcite cement, calcitized dolomite, calcite veins, saddle dolomite and stylolites filled by the second phase of oil entrance. Together with the above mentioned diagenetic alterations, the arenites are affected by early kaolinitization of feldspars and the scarce formation of clay rim and epimatrix of illite. All sandstones and dolomitized carbonate rocks show high intercrystalline and intergranular porosity which is full by biodegraded hydrocarbons (solid bitumen). The biodegradation affects alkanes, isoprenoids and partially hopanes and steranes saturated hydrocarbons. Aromatics hydrocarbons, like naphthalenes, phenanthrenes, dibenzothiophenes and triaromatics are also affected by biodegradation. Results indicate that the first HC emplacement corresponds to early stage of calcite and dolomite cementation, and the second and more important emplacement is related to fracturation processes resulting in the formation of excellent reservoirs.     

江西北部岩溶地貌陆生贝类物种多样性

作者于2013年5月至6月调查了位于江西北部地区岩溶地貌陆生贝类资源,共采得陆生贝类63种及亚种(含5个未定种),分别隶属于12科21属,其中1个新种,即石钟山弯螺(Sinoennea shizhongshanensis sp.nov),优势种为雪土鸥螺(Georissa niva)、细纹喇叭螺(Boysidia gracilis)、囊喇叭螺(Boysidia dorsata)和灰尖巴蜗牛(Bradybaena ravida ravida)。区系成分以东洋界成分为主,占总种类数的61.90%。计算了江西北部地区岩溶地貌陆生贝类多样性指数,其中Margalef丰富度指数(dMA)为2.205~4.273,Shannon-Wiener多样性指数(H′)为1.960~3.374,Pielou均匀度指数(Jsw)为0.448~0.681。与邻近自然保护区比较,江西北部地区岩溶地貌陆生贝类较为丰富,与其他自然保护区物种相似性较低。     

Innovation for sustainable energy from a pro-poor perspective

The development and transfer of clean energy technologies to achieve universal energy access is challenging due to the inherent complexities of the energy sector, and the energy governance and financial systems in developing economies. Innovation is an essential part of successfully addressing these difficulties. Duplicating the energy infrastructure models of developed countries will not be sufficient to meet the needs of poor consumers. To the extent that innovation can accelerate energy access, it is important to understand the specific types of innovations that are necessary and how they might be facilitated. The general features of existing international clean energy innovation systems, which are predominantly driven by the markets and emissions reduction mechanisms of developed and rapidly growing emerging economies, are reviewed and the alignment of these systems to the innovation processes required to extend energy access globally is evaluated. Drawing on the innovation policy literature, the attributes of effective international and domestic energy innovation systems that are pro-poor and the associated policy approaches are identified.     

Scientists’ framing of the ocean science–policy interface

Scientists’ ideas, beliefs, and discourses form the frames that shape their choices about which research to pursue, their approaches to collaboration and communicating results, and how they evaluate research outputs and outcomes. To achieve ocean sustainability, there are increasing calls for new levels of engagement and collaboration between scientists and policy-makers; scientists’ willingness to engage depends on their current and evolving frames. Here, I present results about how scientists involved in diverse fields of ocean research perceived their role as scientists working at or near the ocean science–policy interface and how this related to their perceptions regarding ocean research priorities. The survey of 2187 physical, ecological and social scientists from 94 countries showed that scientists held different perspectives about their appropriate level of engagement at the ocean science–policy interface and the relative primacy of science versus politics in formulating ocean policy. Six clusters of scientists varied in their frames; three clusters accounted for 94% of the sample. Of 67 research questions identified from 22 research prioritization and horizon scanning exercises, the top eight were shared among all three clusters, showing consistency in research priorities across scientists with different framings of their role at the science–policy interface. Five focused on the mechanisms and effects of global change on oceans, two focused on data collection and management for long-term ocean monitoring, and one focused on the links between biodiversity and ecological function at different scales. The results from this survey demonstrated that scientists’ framings of the role of ocean science at the science–policy interface can be quantified in surveys, that framing varies among scientists, and that research priorities vary according to the framings.     

塔里木盆地英买力地区原油地球化学特征与族群划分

塔里木盆地英买力地区油气成因复杂,采用多馏分、多组分化学成分分析及单体烃碳同位素分析途径,对该区海相、陆相油进行精细分析。结果表明,英买力油田主要有两大类油组,分别是南部YM2井区的海相油(I类)和北部YM7井区的陆相油(Ⅱ类),各自具有典型的海相油与陆相油的特征。进一步分析表明,两大油组内部仍有分异。将第二油组进一步分为两亚类,以中、古生界产层为主的正常黑油和重质油为一类(Ⅱa),以古近系为主的凝析油为另一类(Ⅱb)。两亚类原油正构烷烃单体烃同位素稍有差异,芳烃组成与分布具有显著差异。较之于Ⅱa原油,Ⅱb原油富含联苯系列与氧芴系列、不同类型芳烃系列中以低分子量同系物占绝对优势,其正构烷烃单体烃碳同位素更重,与相邻的羊塔克地区原油表现出一定的相似性,表明两者之间有一定的成因联系,前者可能为混源油,由位于库车坳陷中拜城凹陷提供两种陆相烃源岩。英买力地区陆相油并非以往确认的一种成因类型,可能至少由两套性质迥异的中生界烃源岩供烃。英买力地区第一类海相油(I类)尽管生物标志物特征相近,但分析原油的单体烃碳同位素具有显著差异,同样存在油气混源的可能。英买力地区海、陆相原油特征与成因的深入剖析,对于该区精细油源确认、油气成藏机制乃至油气资源评价具有重要意义。     

地下水-陆生植被系统研究评述

依赖于地下水的生态系统广泛分布,潜水含水层本身是个生态系统,地下水不仅维持许多水生生态系统,而且是干旱-半干旱地区陆生植被生存的重要水源。研究地下水与植被的相互联系是生态水文地质学的主要组成部分,重点介绍地下水-植被系统的研究方法。植被吸收的地下水量占总蒸腾量的比例是评价植被依赖地下水程度的一个定量指标,蒸腾量比例呈季节性与区域性变化,取决于植被类型、地下水位埋深与动态变化、土壤岩性与气候条件。植被总蒸腾量可以用涡流相关系统测量。地下水的蒸腾量可以用植物茎流计测量,或者用地下水位昼夜变化估算。用同位素混合模型也能估算地下水占总蒸腾量的比例。植被对地下水位下降的响应可能有两种形式,一种是线性比例响应,另一种是临界突变响应,只有通过长期系统观测植被长势与地下水位的变化才能利用统计分析建立两者响应关系。目前,植被-水文模型只能模拟植被冠层截流与蒸腾对土壤水与地下水的影响,或者模拟土壤水-地下水对植被生长的影响,地下水与植被相互作用与反馈的耦合模型还是个空白。     

Last glacial terrestrial vegetation record of leaf wax n-alkanols in the northern South China Sea: Contrast to scenarios from long-chain n-alkanes

Long-chain n-alkanols and n-alkanes in core sediments from the northern South China Sea (SCS) were measured to make a comparison during terrestrial vegetation reconstruction from ~42 ka to ~7 ka. The results showed that terrestrial vegetation record from long-chain n-alkanes matched well with previous studies in nearby cores, showing that more C₄ plants developed during the Last Glacial Maximum (LGM) and C₃ plants dominated in the interglacial period. However, these scenarios were not revealed by terrestrial vegetation reconstruction using long-chain n-alkanols, which showed C₃ plant expansion during the LGM. The discrepancy during the interglacial period could be attributed to the aerobic degradation of functionalized long-chain n-alkanols in the oxygen-rich bottom water, resulting in poor preservation of terrestrial vegetation signals. On the other hand, the different advantages of functionalized n-alkanols and non-functional n-alkanes to record local and distal vegetation signals, respectively, may offer a potential explanation for the contradiction during the LGM when the SCS was characterized by low-oxygen deep water. Nevertheless, large variations on n-alkyl lipid compositions in C₃/C₄ plants could play a part in modulating sedimentary long-chain n-alkanols and n-alkanes toward different vegetation signals, thereby suggesting that caution must be taken in respect to the terrestrial vegetation reconstruction using long-chain n-alkanes and long-chain n-alkanols.