宾川苦橄岩的水含量:对峨眉山大火成岩省成因的启示

近几年来对西伯利亚、哥伦比亚河、塔里木等大火成岩省原始岩浆水含量的分析表明,其源区的显著水化是造成地 幔熔融异常的重要原因之一。峨眉山大火成岩省是全球二叠纪大火成岩省的重要组成之一,前期对其位于宾川剖面底部的 大理苦橄岩水含量的分析表明地幔的水化在峨眉山大火成岩省形成中起到了重要作用。然而大理苦橄岩只能代表峨眉山大 火成岩省初始阶段的熔融条件,而在其后的喷发历史中水是否也起到了关键作用还不清楚。定量分析后阶段喷发的苦橄岩 水含量有助于更完整评估水在大火成岩省形成中的作用。本文报道了位于峨眉山大火成岩省西部岩带宾川剖面中上部的宾 川苦橄岩的水含量,结果表明原始岩浆水含量可高达2.8 wt%,比大理苦橄岩的水含量略低,但仍显著高于MORB 和OIB, 达到了岛弧玄武岩的水含量范围。这表明水对整个大火成岩省的形成中都扮演了重要角色。     

西南三江地区造山演化过程及成矿时空分布

三江地区单凭“一次造山”是难以圆满解释的。本文试以“多次造山”多期成矿”的思路作出合理说明。晚古生代－中生代早期多岛海造山阶段,羌塘弧、江达弧和临沧弧应为前锋弧,其后由一系列弧后盆地和岛弧或残余弧（或微大陆）组成。中生代中－晚期为陆内俯冲造山阶段,推测金沙江带、哀牢山带和龙门山－锦屏山带为俯冲主边界,从而形成本区燕山期重熔型花岗岩带,控制相应矿产的分布特征。新生代陆内转换造山阶段,造成特征的构造－岩浆－成矿带,具有生成大型或超大型矿床的潜力。     

黑色电气石矿物组成与红外辐射特性的关系

作者对产自云南马关－麻粟坡矿带、广西钟山八步矿区的黑色电气石进行了矿物组成及化学成分的分析测试。实验表明，不同矿点黑色电气石的矿物组成和化学成分存在明显差异，化学成分对红外辐射特性存在一定影响，氧化镁含量较高的镁电气石具有高的红外法向比辐射率。论文对电气石的化学成分与成因的相互关系进行了讨论，为合理选矿，有效利用黑色电气石资源提供了实践和理论依据。     

青藏高原地面有效辐射变化及其对表层土温的影响

利用青藏高原格尔木、狮泉河、昌都日射站及中国科学院冰冻圈观测研究站的观测资料,分析了高原有效辐射的变化,在此基础上结合土壤温度资料讨论了高原北部有效辐射的变化对表层土壤热状况的影响.结果显示：1）青藏高原有效辐射变化因所处的区域不同而异,高原东北部、西部及高原腹地有效辐射总体呈减小的趋势,高原东南部有效辐射呈增大的趋势...     

Pacific decadal oscillation impact on East China precipitation and its imprint in new geological documents

This paper briefly introduces the history of the study of the Pacific decadal oscillation (PDO) and explores the relationship between the PDO and sediment grain size from two typical sediment cores from the lower Changjiang (Yangtze River) and Huanghe (Yellow River) estuaries. It is found that the median grain sizes of both cores exhibit relatively high correlation with the PDO. This is because the PDO causes interdecadal variability of precipitation in the East Asia Monsoon region, thus changing the hydrodynamics in both the Changjiang and Huanghe catchments, eventually resulting in variation of sediment grain size. Our analysis also revealed that during different phases of the PDO, the sediment grain size of the Changjiang and Huanghe estuaries showed different variations in cold and warm PDO phases. This is related to movement of the precipitation center driven by the shift in different PDO phases. Moreover, we compared more high resolution geological proxies with the PDO, including stalagmites and tree rings, in East China over the past century. The results indicate that variations of studied geological proxies are generally well correlated with the PDO but have some differences. Finally, longer variations of sediment grain sizes in the Changjiang and Huanghe estuaries are compared with a reconstructed PDO over the last 200 years; sediment grain sizes were still correlated with the PDO, implying that sediment grain size may be used as a new proxy for studying the long-term behavior of the PDO. This result supports previous knowledge of the PDO impact on East China climate evolution and offers a new proxy for further PDO study. Our study will improve paleoenvironment reconstruction in East China on a decadal time scale and benefit future climatic predictions.     

Carbon pools and fluxes in the China Seas and adjacent oceans

The China Seas include the South China Sea, East China Sea, Yellow Sea, and Bohai Sea. Located off the Northwestern Pacific margin, covering 4700000 km~2 from tropical to northern temperate zones, and including a variety of continental margins/basins and depths, the China Seas provide typical cases for carbon budget studies. The South China Sea being a deep basin and part of the Western Pacific Warm Pool is characterized by oceanic features; the East China Sea with a wide continental shelf, enormous terrestrial discharges and open margins to the West Pacific, is featured by strong cross-shelf materials transport; the Yellow Sea is featured by the confluence of cold and warm waters; and the Bohai Sea is a shallow semiclosed gulf with strong impacts of human activities. Three large rivers, the Yangtze River, Yellow River, and Pearl River, flow into the East China Sea, the Bohai Sea, and the South China Sea, respectively. The Kuroshio Current at the outer margin of the Chinese continental shelf is one of the two major western boundary currents of the world oceans and its strength and position directly affect the regional climate of China. These characteristics make the China Seas a typical case of marginal seas to study carbon storage and fluxes. This paper systematically analyzes the literature data on the carbon pools and fluxes of the Bohai Sea,Yellow Sea, East China Sea, and South China Sea, including different interfaces(land-sea, sea-air, sediment-water, and marginal sea-open ocean) and different ecosystems(mangroves, wetland, seagrass beds, macroalgae mariculture, coral reefs, euphotic zones, and water column). Among the four seas, the Bohai Sea and South China Sea are acting as CO_2 sources, releasing about0.22 and 13.86–33.60 Tg C yr~(-1) into the atmosphere, respectively, whereas the Yellow Sea and East China Sea are acting as carbon sinks, absorbing about 1.15 and 6.92–23.30 Tg C yr~(-1) of atmospheric CO_2, respectively. Overall, if only the CO_2 exchange at the sea-air interface is considered, the Chinese marginal seas appear to be a source of atmospheric CO_2, with a net release of 6.01–9.33 Tg C yr~(-1), mainly from the inputs of rivers and adjacent oceans. The riverine dissolved inorganic carbon (DIC) input into the Bohai Sea and Yellow Sea, East China Sea, and South China Sea are 5.04, 14.60, and 40.14 Tg C yr~(-1),respectively. The DIC input from adjacent oceans is as high as 144.81 Tg C yr~(-1), significantly exceeding the carbon released from the seas to the atmosphere. In terms of output, the depositional fluxes of organic carbon in the Bohai Sea, Yellow Sea, East China Sea, and South China Sea are 2.00, 3.60, 7.40, and 5.92 Tg C yr~(-1), respectively. The fluxes of organic carbon from the East China Sea and South China Sea to the adjacent oceans are 15.25–36.70 and 43.93 Tg C yr~(-1), respectively. The annual carbon storage of mangroves, wetlands, and seagrass in Chinese coastal waters is 0.36–1.75 Tg C yr~(-1), with a dissolved organic carbon(DOC) output from seagrass beds of up to 0.59 Tg C yr~(-1). Removable organic carbon flux by Chinese macroalgae mariculture account for 0.68 Tg C yr~(-1) and the associated POC depositional and DOC releasing fluxes are 0.14 and 0.82 Tg C yr~(-1), respectively. Thus, in total, the annual output of organic carbon, which is mainly DOC, in the China Seas is 81.72–104.56 Tg C yr~(-1). The DOC efflux from the East China Sea to the adjacent oceans is 15.00–35.00 Tg C yr~(-1). The DOC efflux from the South China Sea is 31.39 Tg C yr~(-1). Although the marginal China Seas seem to be a source of atmospheric CO_2 based on the CO_2 flux at the sea-air interface, the combined effects of the riverine input in the area, oceanic input, depositional export,and microbial carbon pump(DOC conversion and output) indicate that the China Seas represent an important carbon storage area.     

Middle Devonian-Tournaisian rocks and biota on Hainan Island, South China

On the basis of new paleontological data,the sequence and distributions of the Middle Devonian-Tournaisian rocks on Hainan Island have been sorted out for the first time.The Devonian rocks include the Middle Devonian Jinbo Formation and the Upper Devonian Changjiang Formation,which are distributed in northwestern Hainan Island.The Jinbo Formation is represented by631 m of littoral facies deposits,and was intruded by the Yanshanian granite in the base.The presence of chitinozoans Eisenackitina caster,Funsochitina pilosa,and Lagenochitina amottensis indicates the Givetian in age.The Changjiang Formation is made up of 140 m of neritic facies rocks,and contains the Famennian conodonts Palmatolepis gracilis sigmoidalis,Polygnathus germanus,and corals Cystophrentis kalaohoensis.The Devonian-Tournaisian transition beds,the lower part of the Jishi Formation,are composed of 61–129 m sandstone and siltstone,with gastropods Euomphalus spp.and brachiopods,and marked by conglomerate with the underlying Devonian rocks.The middle-upper part of the Tournaisian Jishi Formation consists of 100–251 m clastic and carbonate rocks,containing abundant corals Pseudoularinia irregularis,conodonts Siphonodella isosticha,trilobites Weberiphillipsia linguiformis,and brachiopods.On the basis of the occurrence of Xinanosprifer flabellum and Homotoma sp.,the Nanhao Formation in southern Hainan Island is now regarded as the Lower Silurian,instead of the previously designated Lower Carboniferous.It is confirmed that no Carboniferous rocks occurred in the area south to the Gancheng-Wanning Fault.     

磁铁矿的穆斯堡尔谱研究

我们对大冶、马坑、大顶、黄沙坪、鞍山五个矿区的七个铁矿石样品中的磁铁矿作了室温~(57)Fe和~(119)Sn穆斯堡尔谱测定,并根据穆斯堡尔数据和化学分析推算出磁铁矿的非理想配比的分子结构式. 初步研究表明,不同的成矿条件和Zn、Mg等二价阳离子的类质同像替代的多少,明显地影响晶胞参数和穆斯堡尔参数.文中讨论了它们的变化规律性.     

基于Datist的测震分析月报自动产出技术研发

针对四川测震台网运行月报中关于测震分析章节编写过程中的程序化工作流程,依托于数据专家(Datist)自动化流程实现了数据源读取、数据清洗、目录统计、绘制震中分布图、计算速报结果自评和报告自动产出等功能,辅助完成月报生成。实践证明该成果可有效减轻地震监测人员的工作负担,提高工作效率。