国际碳税格局及其对中国的启示

本文在总结分析全球已经实施碳税的国家碳税实施情况及其效果,评价分析国内外学者对中国征收碳税的相关研究和科学观点的基础上,针对中国碳税设计提出如下建议：目前实施碳税的大多是发达国家,国际上征收碳税的舆论日益高涨,但国内对碳税征收要素研究还不透彻,依据中国的国情开征碳税环境尚不成熟,未来需要进一步加强对碳税开征各要素的调研。     

Perfluoroalkyl and polyfluoroalkyl substances in sediments from South Bohai coastal watersheds,China

This study investigated the concentrations and distribution of Perfluoroalkyl and polyfluoroalkyl substances (PFAS) in sediments of 12 rivers from South Bohai coastal watersheds. The highest concentrations of ΣPFAS (31.920 ng g⁻¹ dw) and PFOA (29.021 ng g⁻¹ dw) were found in sediments from the Xiaoqing River, which was indicative of local point sources in this region. As for other rivers, concentrations of ΣPFAS ranged from 0.218 to 1.583 ng g⁻¹ dw were found in the coastal sediments and from 0.167 to 1.953 ng g⁻¹ dw in the riverine sediments. Predominant PFAS from coastal and riverine areas were PFOA and PFBS, with percentages of 30% and 35%, respectively. Partitioning analysis showed the concentrations of PFNA, PFDA and PFHxS were significantly correlated with organic carbon. The results of a preliminary environmental hazard assessment showed that PFOS posed the highest hazard in the Mi River, while PFOA posed a relative higher hazard in the Xiaoqing River.     

Distribution and source of heavy metals in the surface sediments from the near-shore area,north Jiangsu Province,China

Samples of surface sediment and vibrocore were collected in the near-shore area of north Jiangsu Province for grain size, elements, ²¹⁰Pb_excess and ¹³⁷Cs analyses. In our study area, the diversity of metal concentration was controlled not by the grain size, but by the source. The element content of the old Yellow River Delta was used as baseline for our study area. Geoaccumulation indexes indicate that no station was polluted by Cu, Pb, Zn and As, but the I_geo values of As were close to zero in some stations. Slight pollution caused by Cd was observed in some stations. Correlation and enrichment factors suggest that Cu, Pb and Zn are lithogenic in origin, while As and Cd are mixed in origin. Especially, in some polluted stations Cd was obviously anthropogenic in origin.     

塔里木盆地塔北隆起奥陶系-侏罗系泥岩稀土元素地球化学特征

分析了塔里木盆地塔北隆起奥陶系、三叠系和侏罗系泥岩的稀土元素丰度。不同时代泥岩都表现出轻稀土富集、重稀土含量均一和具有Eu负异常特征;但它们∑LREE/∑HREE、LaN/YbN、(La/Yb)UCC、Eu/Eu和Ce/Ce等参数则显示这些泥岩形成时的物源和环境有差别。奥陶纪时,研究区处于相对稳定的沉积环境,物源为成熟度高的大陆上地壳;二叠纪到三叠纪构造-火山活动强烈,部分沉积物来自火山岩的风化;侏罗纪塔北隆起区则进入稳定构造沉降阶段。这一差别对认识塔里木盆地及周边造山带形成演化研究有指示意义。     

表生环境条件形成的石盐流体包裹体研究进展

系统介绍了近些年来国外在表生环境条件形成的石盐流体包裹体均一温度、水体组分、δD和δ18O同位素、气体成分及微生物等信息提取和应用方面的研究进展。这些研究进展充分表明表生环境条件形成的石盐流体包裹体是目前利用蒸发盐定量获取古气候环境（温度、湿度）参数、揭示海洋和盐湖水体地质历史时期的长期演化以及丰富和深化成盐成矿理论的良好地质载体。分析了我国目前在这一研究领域同国外相比的差距、潜在优势和发展前景。     

Geochemical distribution and removal of As,Fe, Mn and Al in a surface water system affected by acid mine drainage at a coalfield in Southwestern China

The chemical characteristics, formation and natural attenuation of pollutants in the coal acid mine drainage (AMD) at Xingren coalfield, Southwest China, are discussed in this paper based on the results of a geochemical investigation as well as geological and hydrogeological background information. The chemical composition of the AMD is controlled by the dissolution of sulfide minerals in the coal seam, the initial composition of the groundwater and the water–rock interaction. The AMD is characterized by high sulfate concentrations, high levels of dissolved metals (Fe, Al, Mn, etc.) and low pH values. Ca²⁺ and SO₄ ²⁻ are the dominant cation and anion in the AMD, respectively, while Ca²⁺ and HCO₃ ⁻ are present at significant levels in background water and surface water after the drainage leaves the mine site. The pH and alkalinity increase asymptotically with the distance along the flow path, while concentrations of sulfate, ferrous iron, aluminum and manganese are typically controlled by the deposition of secondary minerals. Low concentrations of As and other pollutants in the surface waters of the Xingren coalfield could be due to relatively low quantities being released from coal seams, to adsorption and coprecipitation on secondary minerals in stream sediments, and to dilution by unpolluted surface recharge. Although As is not the most serious water quality problem in the Xingren region at present, it is still a potential environmental problem. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

大别—苏鲁超高压榴辉岩中高钛石榴子石的成分特征及其与金红石包裹体的成因联系

石榴子石是榴辉岩中的基本造岩矿物。本文对苏鲁地体中的毛北榴辉岩和大别地体中的双河榴辉岩中的石榴子石进行了研究。结果显示,石榴子石都表现出中心“富”钛特征,即石榴子石颗粒的中心部位的TiO₂含量（0.10%~0.50%）明显高于正常榴辉岩中石榴子石的钛含量(TiO₂ 一般<0.1%)。另外,在石榴子石中心部位含有大量金红石及其它钛矿物包裹体,其定向分布特征揭示其出溶成因模式。计算结果显示,出溶金红石的原始石榴子石大约含1.7% TiO₂,揭示其超深源特征。此外,在石榴子石中发现了一颗TiO₂含量达8%~9%的钙铝榴石,具超深源成因特征。因此,本文认为超钛钙铝榴石也是超高压变质作用的标志矿物。     

汶川地震(Ms8.0）地表建筑体变形特征及其构造意义

通过汶川地震震区大量的实地考察已证实沿着早先活动断裂主要发育了两条地表破裂带：一条是沿着映秀－北川断裂产生的逆冲伴随右旋走滑破裂带,长275km,最大垂直位移达11m,水平位移达12m; 另一条纯逆冲性质的破裂带,沿着灌县－安县断裂发育,最大垂直位移达4m。活动断裂之上的地表破裂带是野外工作中确定地震断裂性质的重要现象。另外,在活动断裂相邻区域和远离区域的路面以及建筑体还大量存在变形现象。通常沿活动断裂产生的地表破裂是典型的同震破裂,相邻区域的地表路面及建筑体发育的变形属于次生变形,远离区域发育的变形则属于震后变形。对次生变形和震后变形测量数据的应用容易影响活动断裂特征的确定和性质的判断,因为路面等建筑体上的挤压拱起、叠置以及水平错断等现象多是受到地震过程中通过断裂活动突然释放的巨大能量作用在局部地表建筑体产生的变形。但是,分布广泛的挤压现象暗示了区域上挤压应力场环境,有利于地表同震破裂位置的推测及地震断裂性质的判断。     

Evidence for Tibetan Plateau Uplift in Qaidam Basin before Eocene-Oligocene Boundary and Its Climatic Implications

Geometry analysis of the Hongsanhan (红三旱) Section in the northwestern Qaidam basin illustrates the typical growth strata in the Xiaganchaigou (下干柴沟) Formation. The age and sedimentation rates of the Xiaganchaigou and the Shangganchaigou (上干柴沟) formations were determined by the high-resolution magnetostratigraphy. This result shows that the growth strata began to form at ca. 38.0 Ma and increased sedimentation rates occurred at ca. 37.0 Ma. The uplift of the Tibetan plateau before the Eocene-Oligocene boundary is confirmed, which enables us to better understand the relationship between climatic changes and the tectonic uplift. This uplift event could have resuited in the regional drying by blocking the moisture and contributed to the Eocene-Oligocene boundary global cooling event due to the declining atmospheric CO2 concentrations by increased weathering of the mountains.     

青藏高原及周边现今构造变形的运动学

青藏高原现今构造变形的定量化研究是理解其动力过程的基础 ,近年来高速发展的GPS(全球定位系统 )技术为测量大尺度现今构造变形提供了最有效的手段。我们利用青藏高原及周边的5 5 3个GPS观测数据给出了其现今构造变形的速度场 ,表明印度和欧亚板块之间的相对运动主要被青藏高原周边的地壳缩短和内部的走滑剪切所调整吸收。其中 ,喜马拉雅山系吸收了青藏高原总缩短量的 4 4%～ 5 3% ,北部的阿尔金山、祁连山和柴达木盆地吸收了 1 5 %～ 1 7% ,高原内部吸收了 32 %～4 1 %。青藏高原的“向东挤出”实际上是地壳物质的向东流动而不是刚性地块的挤出。这一地壳物质流动带在高原西部以地表张性正断层和共轭剪切走滑断层为特征 ,到高原中东部转换为巨型的弧形走滑断裂带 ,再到高原东北缘转换为地壳缩短和绕东喜马拉雅构造结的顺时针旋转。青藏高原的大尺度现今构造变形以连续变形为特