阿尔泰造山带南缘昆格依特岩体LA-ICP-MS锆石U-Pb年代学、岩石成因及其地质意义

昆格依特岩体出露于阿尔泰造山带南缘青河县大青格里河昆格依特一带,主要为角闪黑云英云闪长岩。LA-ICP-MS锆石U-Pb定年结果显示,锆石的²⁰⁶Pb/²³⁸U年龄加权平均值为(403.4±7.4)Ma,表明该岩体形成于早泥盆世。岩体的SiO₂含量介于52.39%~71.89%之间,里特曼指数为0.68~1.53,A/CNK 值为0.76~1.06,属中钾、钙碱性、准铝质-弱过铝质岩石。具有富集Cs、Rb、Th、U等大离子亲石元素和轻稀土元素,相对亏损Nb、Ta、Hf、Ti等高场强元素和重稀土元素,弱的负Eu异常(δEu=0.56~0.86)的岛弧岩浆岩特征。结合区域地质资料,认为阿尔泰造山带南缘早泥盆世昆格依特岩体形成于活动大陆边缘的陆缘弧构造环境,是古亚洲洋俯冲过程中幔源的基性岩浆底侵下地壳使之熔融,并发生了岩浆混合和分异作用的产物。     

大庆油田北部河流相储层沉积微相与水淹特征

大庆油田北部发育砂质辫状河道、曲流河道、高弯度分流河道和低弯度分流河道等砂体类型。以井间可对比的单一河流沉积物为研究单元 ,从河流相储层成因特征入手 ,应用油田开发后期密井网资料开展各类河流砂体细分微相研究。重点阐述了各类砂体的规模、宽厚比、发育的主要微相、物性特征及层内非均质特点。应用不同时期密闭取心检查井资料、测井水淹解释、生产动态测试资料 ,结合不同砂体和微相的非均质特点研究了不同微相的水淹变化特征。研究结果表明 ,不同阶段各类砂体层内及平面水淹变化特征不同 ,高含水后期剩余油主要分布于河间薄层砂、部分决口水道和废弃河道微相中 ,低弯度分流河道砂体中剩余油相对发育     

Fe3+纳米胶体颗粒的光吸收边蓝移与溶液中Al/Fe比的关系

合成了n（Al）／n（Fe）和碱化度不同的45个聚合氯化铝铁（PAFC）样品,进行了光谱分析,结果显示光吸收边蓝移或红移以及Fe（Ⅲ）羟基氧化物和Al-Fe共聚体纳米胶体颗粒大小分布与溶液的Al／Fe比和碱化度（B=[OH]／[Al＋Fe]）密切相关。电镜观察和电子衍射分析表明：Al（Ⅲ）的加入使Fe（Ⅲ）羟基氧化物和Al-Fe共聚体纳米胶体颗粒变小、有序度降低是造成PAFE光吸收边蓝移和保持胶体颗粒在亚稳定状态下存在的重要原因。当n（Al）／n（Fe）〉8：2后,PAFC溶液中Fe（Ⅲ）羟基氧化物和Al-Fe共聚体胶体主要以〈10m的纳米颗粒形态存在,对应的光谱能级提高到26000cm^-1以上,且各种曰值下Fe^3＋的光谱能级趋于一致。这表明,在大量Al（Ⅲ）存在条件下,PAFE中Fe3^＋的所处的化学环境相似。点能谱分析显示,n（Al）／n（Fe）=4：6的样品中颗粒物的化学计量比最接近AlOOH,FeOOH,溶液的稳定性最差。     

榴辉岩中石英出溶体的拉曼光谱学研究及其构造意义

利用拉曼光谱学和费氏台方法对若干地区超高压榴辉岩中柯石英和榴辉岩中石英出溶体的超显微构造特征进行了研究.研究结果表明, 石榴石(或绿辉石) 中柯石英向石英相变是一个连续变化过程.绿辉石中石英出溶体和主晶具有一定的晶体学拓扑关系, 即石英出溶体长轴有两个展布方向: 平行于绿辉石(10 0) 裂理面和平行于绿辉石(- 10 1) 面.目前, 部分学者推断榴辉岩绿辉石中石英出溶体可作为超高压变质作用的标志.笔者认为, 棒状定向石英在绿辉石中出溶的温压条件和出溶机理尚未查明.因此, 需加强过量二氧化硅单斜辉石出溶机理的超高压实验研究, 从而为证实石英出溶体作为超高压标志提供实验定量约束.      

Downstream patterns of bed sediment-borne metals,minerals and organic matter in a stream system receiving acidic mine effluent: A preliminary study

Different downstream variation patterns were observed for a range of bed sediment-borne metals (aqua regia-extractable fraction) in a subtropical stream system receiving acid mine drainage. Mine-originated Fe tended to be deposited in the acidic (mean pH < 4.9) upstream reach in forms of goethite and/or hematite. In contrast, other metals tended to be transported farther downstream and settled in a low-gradient reach with high pH (mean pH > 5.6). The peak of sediment-borne Al, Be, Ca, Cd, Co, Cu, La, Mn, Ni and Zn corresponded very well with the peak of the sediment-borne organic matter, suggesting a close association between the water-borne organic colloids and the inorganic metal oxides/hydroxides during their transport. The marked increase in the sediment-borne Al and Pb started more upstream than the other metals, suggesting that the water-borne Al and Pb were more susceptible to pH rise-induced precipitation, as compared to the other metals. It appeared that the organic colloids played no important role in Pb transport and settlement. The iron precipitates had a limited role to play in affecting the transport and fates of other metals since they were predominantly formed and deposited in the acidic reach, which made them incapable of scavenging cationic metals by co-precipitation or adsorption.     

频率测深的地形影响及其校正方法

从含源麦克斯韦方程出发，按照二维地形条件下的线源非齐次赫姆霍兹方程确定其边界条件，用边界元法计算了起伏地形条件下线源的频测影响曲线，并将其转换为二维地形点源赤道偶极装置频测曲线。总结了地形对频测曲线影响的规律，提出了地形校正的方法。     

鲁西南地区石炭纪—二叠纪含煤岩系层序地层及聚煤特征

根据钻井、测井和地质等资料,对鲁西南地区石炭纪—二叠纪含煤岩系进行了层序地层学与聚煤作用研究。识别出以区域不整合面、古土壤层底面、海侵方向转换面、下切谷砂体底面为代表的4种类型的层序界面;划分出本溪组、太原组、山西组和下石盒子组中的4个三级层序,从下到上依次为SⅢ1、SⅢ2、SⅢ3及SⅢ4。通过对比研究不同层序的含煤性及煤层的发育特征后认为,形成于分流间湾沼泽环境的SⅢ3煤层发育最好,形成于潟湖与沼泽环境的SⅢ1及SⅢ2煤层发育次之,SⅢ4没有煤层发育。在同一个层序内部,泥炭聚集速率与可容空间增加速率之间的平衡状态决定了煤层的厚度,这种平衡状态保持较长时间是煤层形成的基本条件,而与泥炭聚集有关的可容空间的持续增加需要基准面的不断抬升,因此,发育较好的煤层最可能形成于海侵体系域末期,如SⅢ3的TST末期的3号煤层。     

Ecological effects analysis of land use change in coal mining area based on ecosystem service valuing: a case study in Jiawang

Land use change is one of the uppermost driving forces of regional ecosystem change, and has a huge impact on the environmental balance. Mining areas with intensive resources exploitation and utilization have undergone different kinds of environmental influences, such as water pollution and land use cover change. The extensive coal mining in China has led to significant regional land use change resulting in major ecological damage. The objective of this study was to form a clearer picture of the regional ecological environmental situation for promoting ecological protection and improvement by ecosystem service valuing. The case study area was selected at Jiawang town, which has undergone extensive coal mine exploitation for many decades. The study investigated the relationship between land use change and ecological environment, and described the ecosystem service value variations in Jiawang, based on remote sensing and GIS technology. After modification of regional ecosystem service value coefficients, the method was used to evaluate the conditions in the study area from 1990 to 2005 based on the land use/cover information interpreted from TM/ETM+ images. The characters and changes of ecosystem service values were then analyzed both quantitatively and spatially.     

云南老王寨金矿的深部地质过程——来自显微岩相学和元素地球化学的证据

通过老王寨金矿围岩、蚀变岩石、矿石的显微岩相学和元素地球化学的系统研究发现：伴随硅化、碳酸盐化等蚀变和硫化物矿化,岩（矿）石中发育沿粒间、裂隙或角闪石解理纹贯入或穿插的黑色不透明超显微隐晶,经电子探针、扫描电镜和能谱分析鉴定,该固体物质主要由超显微晶石英、硅酸盐、碳酸盐、硫化物以及呈熔离交生关系的金红石、白钨矿和镜铁矿（磁铁矿）组成;熔离交生结构与沉淀共晶结构共存的特有岩相学特征指示成矿流体具备由熔体性质向热液性质转化的特性。结合岩（矿）石稀土微量元素研究,认为这种在透射光显微镜下呈黑色不透明的超显微隐晶固体物质,是具熔浆流体特点和超临界流体性质的地幔流体引发交代蚀变的直接微观表现之一;在交代蚀变过程中其性质由熔浆向地壳热液过渡,同时与地壳物质发生混染而有利于成矿作用的进行。     

Red clay deposits on the Chinese Loess Plateau during 11.0–2.6?Ma and its implications for long-term evolution of East Asian monsoon

Loess and red clay on the Chinese Loess Plateau have produced a detailed history of the East Asia monsoon for the past eight million years. Recently, a well-conserved red clay sequence was discovered at Shilou on the eastern edge of Chinese Loess Plateau, extending the monsoon history back to approximately 11 Ma. By comparing lithologic features, particle size distribution, magnetic susceptibility and deposition rate of Shilou red clay sequence, the paleomonsoon evolution from 11 to 2.6 Ma can be divided into four stages: largely fluctuated stage (11.0–8.0 Ma), relatively strengthened period (8.0–6.5 Ma), extremely changed stage (6.5–4.9 Ma) and further intensified period (4.9–2.6 Ma). The new evidence indicates that variation of paleomonsoon has close relationship with uplifting of the Tibetan Plateau and ongoing global cooling and the consequent expansion of ice sheets during 11.0–2.6 Ma.