首都圈的精密地温观测和地震前兆异常特征

自80年代末,在首都圈陆续建立了一批精密地温观测点(温度计的分辩率为0.0001℃),开展了地温前兆观测,积累了丰富的实测资料和一些典型震例.本文分析了首都圈地温观测的正常动态及影响因素.通过对典型震例的分析,研究了地温的地震前兆异常特征.地温前兆异常形态为阶变型、上升型和脉冲型;它的异常开始至发震时刻最短为28h,最长达1个月左右,皆属短临异常.它的异常幅度为正常日变幅度的几倍至十几倍,但温度的变化量不大,地震前异常累计值最大仅为0.12℃,可谓震前地温的微动态异常.综上所述,精密地温观测记录到了明显的地震短临前兆异常,它是一种比较有效的短临预报手段.     

地温重复性异常与发震构造关系初探

一、前言深入研究三马坊站的地温前兆异常发现,某些地区的地温前兆异常有明显的重复性。主震发生前先有信号震发生,信号震的地温前兆异常与主震的地温前兆异常相似；信号震和主震受同一构造带控制。从地温前兆异常中区分出信号震的前兆异常及其与活动性构造带间的相互关系,是探寻地震短临预报方法的有效途径之一。     

信号震和主震前兆异常探索

信号震和主震的迁移规律与活动地质构造密切相关;信号震和主震的前兆异常曲线形态有某些相似的特征;信号震和主震迁移走向与震源机制解的节面走向大体一致。地震迁移活动的走向指向未来地震的震中。这揭示了地震活动性迁移规律性、信号震和主震前兆异常相似性的内在相关性,对地震预报有深远意义。     

信号震和主震前兆异常探索

信号震和主震的迁移规律与活动地质构造密切相关;信号震和主震的前兆异常曲线形态有某些相似的特征;信号震和主震迁移走向与震源机制解的节面走向大体一致。地震迁移活动的走向指向未来地震的震中。这揭示了地震活动性迁移规律性、信号震和主震前兆异常相似性的内在相关性,对地震预报有深远意义。     

文安5.1级地震前昌平台钻孔应变及地热异常

本文简要介绍了昌平台所处地质环境及各类前兆仪器运行概况,并利用昌平台钻孔应变和地下流体两大学科多个观测手段对2006年7月4日文安5.1级地震的同震响应特征及前兆异常进行了初步的分析和总结,以提高我们对地震前兆异常的认识。     

塔院地温对2003年4月24日唐山地震的前兆反应及同震效应

本文分析了塔院地温在唐山宁河地震前的前兆异常特征及同震效应。宁河地震地温前兆异常和北西向张家口-渤海构造带上发生的地震地温前兆带具有重复性、相似性、继承性和延续性。深入研究,对突破地震预报有深远意义。     

青藏高原东北缘地区水氡异常特征与地震活动关系的探讨

将活动断裂与地震前兆现象相结合,运用地质力学观点,研究了青藏高原东北缘水氡前兆异常的区域特征,如异常本底、异常台项比,初步讨论了前兆异常分布偏离未来震中区的构造动力成因,提供了地震危险性估计、发震地点预报的定量分析指标,这些指标对该区域Ms ≥ 4.1级地震的预报具有一定的实用价值.      

安图M3. 7 及柳树M4. 3 地震前后YＲY——4 钻孔应变观测曲线异常形态

YＲY--4 钻孔应变观测作为一种重要的前兆观测手段,能有效地记录地震前后地应力应变变化。吉林安图境内M3. 7 级地震前后及辽宁营口柳树M4. 3 级地震前,吉林省敦化台及辽宁省营口台YＲY --4 钻孔应变观测分别观测到曲线异常。经对比分析,敦化台观测曲线异常形态为: 异常--走平--发震-- 震后阶跃; 营口地震台观测曲线异常形态为: 异常--返回--发震。两次异常虽然形态各异,但提供了丰富的前兆信息,具有较好的时效性。     

昆仑山口西M_S8.1地震的地温前兆特征和同震效应

一、引言 2001年11月14日17时26分,在新疆、青海交界的昆仑山口西(北纬36.2°,东经90.9°)发生了8.1级地震。这是继1950年8月15日西藏察隅8.6级地震后,中国大陆发生的最大地震。昆仑山口西8.1级地震前,首都圈及华北北部部分地温测点观测到了明显的前兆异常和同震效应。本文对这些前兆异常和同震效应进行了初步分析和研究,这对进一步分析研究地温观测资料的前兆特征,提高地温观测资料预报地震水平是十分有益的。     

1995年7月至1996年2月中缅边境、武定及丽江大地震的断层形变前兆初步分析

一、引言 1995年7月至1996年2月7个月内,云南省境内由南向北连续发生中缅边境7.3级、武定6.5级、丽江7.0级地震,如此连发性地震在历史上也少有。震前断层形变测点均有较好的中期及短期前兆反应,云南省地震局曾将永胜测点的较大异常做为对中缅边境7.3级大震预测的重要依据之一,国家地震局地壳应力研究所又根据永胜巨大异常系列的发展曾对丽江7.0级地震进行过预测,国家地震局预报中心在震前又根据永胜变化进一步     

桂东北铅锌矿床银的富集规律

作者对桂东北地区铅锌矿床中银的产出特征和富集规律进行了阐述。银主要以首次发现的含银硫盐矿物（深红银矿、银黝铜矿和含银锌黝铜矿等）产出，其次呈杂质元素分散在金属硫化物中，银的含量按方铅矿、黄铜矿、闪锌矿、黄铁矿的顺序依次降低，矿体从上向下具Ｃｕ、Ｐｂ（Ａｇ），Ｚｎ→Ｐｂ，Ｚｎ→Ｚｎ的垂向变化规律，银主要富集于上部，并与方铅矿、黄铜矿紧密伴生。     

内蒙古大井锡-多金属矿床伴生金矿化特征及矿床成因

大井矿床是我国北方重要的锡，铜，银，铅，锌等多矿种大型矿床，矿床铜，锡矿化即有关，又有分离，伴生的金矿化局部较好，可能与铜矿化阶段的黄铁矿化有关，浮选铜矿尾砂中的Au含量较高，有潜在的经济价值，独立的黄铁矿（毒砂）脉中的金，银矿资源应予评价，大井矿床东北约10km处叶腊石（巴林石）矿床中金矿化的发现为高S型浅成低温热液银-金-多金属矿床找矿提供了重要线索，说明大井外围有着较好的银-金-多金属矿找矿前景，大井矿床是次火山热液型锡-铜-多金属矿床，成矿物质可能来自基底及燕山期岩浆岩。     

维宝铅锌矿床地质与地球化学特征

维宝铅锌矿是2002~2003年中国地质调查局青藏高原东缘国土资源综合调查项目子题《新疆昆仑山东段布喀达坂峰—依吞布拉克1∶20万区域化探》项目的主要成果,经过几年的普查证实矿床具中型以上规模。Cu、Pb、Zn、A g区化最高值依次为93.1×10-6、291.9×1-0 6、359.7×1-0 6、1 673×10-6。矿床位于蓟县系狼牙山组大理岩夹钙质粉砂岩段的矽卡岩带中,矿化蚀变带宽约150 m,长度大于3 000 m,矿体延深大于400 m。地表共有矿体21条,形态为似层状和透镜状,属层控矽卡岩型铅锌矿床。矿石类型有条带状和浸染状。主要金属矿物为方铅矿、闪锌石和黄铜矿。累计求得Pb+Zn资源量为61.43万t。     

高岭石对重金属离子的吸附机理及其溶液的pH条件

高岭石对Cu^2+,Pb^2+离子的吸附实验及高岭石的溶解实验表明,高岭石对重金属离子的吸附有别于石英单一表面配位模式,离子交换和表面配位模式并存,并随溶液pH由酸性往碱性的变化发生规律性的演替：pH<6.5时主要表现为外圈层配位的离子交换吸附,且在pH<4时由于受到高岭石表层中铝的高溶出及溶液中较高离子强度的影响,高岭石对Cu^2+,Pb^2+离子的吸附率较低,pH为5～6时由于高岭石端面的荷电性为近中性,吸附率则有明显的提升并且表现为一个吸附平台;pH>6.5时离子交换和表面配位均为重要吸附机制,pH再升高时沉淀机制则起着重要作用。研究表明,pH调控高岭石-水界面溶解与质子化-去质子化反应过程,并影响着Cu^2+,Pb^2+离子的吸附行为。最后采用Sverjensky(1993)表面配位的物理模型对吸附结果作了描述。     

Porphyry and Skarn Cu-Mo-Pb-Zn-Ag-Au Metallogeny of the Gangdise Plutonic-Volcanic Arc, Tibet

PORPHYRY AND SKARN Cu-Mo-Pb-Zn-Ag-Au METALLOGENY OF THE GANGDISE PLUTONIC -VOLCANIC ARC, TIBETtheNational973Project“MetallogenicBackgroundandProspectiveEvaluationoftheGangdiseBelt”     

得尔布干有色、贵金属成矿区、带划分

得尔布干成矿区位于蒙古-额霍茨克断裂与得尔布干断裂之间,可划分3个成矿亚区：①上黑龙江（拗陷）成矿亚区,位于得尔布干成矿区北部,以金矿化为主,铜次之,可划分出3个E-W向成矿带;②额尔古纳（隆起）成矿亚区,位于中部,以铅锌银、金矿化为主,铜矿化次之,可划分出3个NE向成矿带;③克鲁伦（半拗、半隆）成矿亚区,位于南部,以铜、银、铅锌矿化为主,金矿化次之,可划分2个NW向成矿带和1个NE向成矿带.     

Flocculation of heavy metals during mixing of freshwater with Caspian Sea water

Flocculation of colloidal size fraction for Cu, Zn, Pb, Ni and Mn was investigated on a series of mixtures with water salinities ranging from 1.5 to 9.5‰ during mixing of Haraz River with the Caspian Sea water. The flocculation trend of Zn (85.5%) > Mn (55.2%) > Cu (39.6%) > Pb (33.7%) > Ni (11.3%) indicates that Cu, Zn, Pb and Mn have non-conservative behavior and Ni has relatively conservative behavior during estuarine mixing. Highest flocculation of heavy metals occurs between salinities of 1.5 and 4.5‰. Statistical analysis indicates that the flocculation of Cu, Zn and Ni is governed by pH and total nitrogen.     

Adsorptive separation of Pb(II) and Cu(II) from aqueous solutions using as-prepared carboxymethylated waste Lyocell fiber

Adsorptive separation of Pb(II) and Cu(II) using modified waste Lyocell fiber adsorbent was investigated in this research. The waste Lyocell fiber was functionalized through carboxymethylation of the hydroxyl moieties using sodium chloroacetate as modifying agent and was crosslinked with epichlorohydrin to provide water stability. The maximum equilibrium batch uptake in single metal system was 353.45 mg/g for Pb(II) and 98.33 mg/g for Cu(II), according to the Langmuir isotherm model. The adsorption rates were very fast and reached equilibrium within 3 and 5?10 min for Cu(II) and Pb(II), respectively. In competitive binary metal system, the uptake of Cu(II) largely decreased to 38.40 mg/g, and Pb(II) selectivity was observed. Elemental and functional characterization suggested that the adsorption proceeded by ion exchange between the adsorbent and metal ions. In a flow-through column system, adsorption followed by desorption aided in effectively eluting ~260 mg of Pb(II) (out of ~300 mg total adsorbed) from the Pb(II)–Cu(II) binary solution. Finally, the adsorbent was very effective in four successive adsorption–desorption cycles with over 99 % uptake and 94 % desorption efficiencies. The present study may provide an alternative option for waste fiber recycling and could be useful in recovering heavy metal ions from aqueous sources to complement their depleting reserves.     

Pb, Cu botanogeochemical anomalies and toxic effects on plant cells in Pb-Zn （Sn） ore fields, Northeast Guangxi Autonomous Region, China

In the Lingchuan-Daoping and Xinglu Pb-Zn ore fields in northern and eastern Guangxi Autonomous Region, Pb, Cu botanogeochemical anomalies may be ascribed to the excessive amounts of Pb and Cu taken up by the root system of plants, such as China fir (Cunninghamia lanceolata Lamb. Hook), mason pine (Pinus massoniana Lamb.) and bracken fern (Pteridium aquilinum var. latiusculum). Under transmission electron microscope (TEM), the excess Pb, Cu in the leaf cells of the plants are present as high electron-density substances, which were precipitated in the leaf cells, causing phytotoxic effects by deforming and injuring cellular tissues. The sorts of toxic elements accumulating in the leaf cells are consistent with those of the botanogeochemically anomalous elements in the polluted soil where the plants grow. In addition, the plants may also be capable of resisting the invasion of excess Cu (and Pb) .     

Ore-forming material sources of the Jurassic Cu–Pb–Zn mineralization in the Qin–Hang ore belt,South China: Constraints from S–Pb isotopes

The Qin–Hang ore belt in South China, which serves as the boundary between the Yangtze and Cathaysia blocks, is marked by extensive Jurassic porphyry-skarn-metasomatic Cu–Pb–Zn polymetallic mineralization. In this contribution, S and Pb isotopic compositions of the Baoshan Cu–Pb–Zn deposit in the western portion of the Qin–Hang ore belt were analyzed to determine the ore-forming material sources in the area. This is coupled by the first systematic collection, compilation and interpretation of previously published S and Pb isotopic data of multiple sulfide minerals to reveal the metal origin and accumulation mechanism of the Cu–Pb–Zn mineralization from the significant deposits in the region (i.e., Dexing, Qibaoshan, Shuikoushan, Baoshan, Huangshaping, Tongshanling and Dabaoshan). The results show that Cu mineralization is characterized by low and narrow δ³⁴S (‰) range of values (–5 to 6) and Pb isotopic ratios (²⁰⁸Pb/²⁰⁴Pb = 38.0–39.0, ²⁰⁷Pb/²⁰⁴Pb = 15.4–15.8, and ²⁰⁶Pb/²⁰⁴Pb = 17.7–18.7), which are consistent with those of local porphyries. In contrast, the Pb–Zn mineralization reveals higher and more variable δ³⁴S (‰) values (–4 to 18) and Pb isotopic ratios (²⁰⁸Pb/²⁰⁴Pb = 38.0–39.5, ²⁰⁷Pb/²⁰⁴Pb = 15.3–16.0, and ²⁰⁶Pb/²⁰⁴Pb = 18.0–19.0) that correspond to wall-rock and basement rock compositions in the region. This indicates that the sulfur and lead that formed the Cu mineralization in the Qin–Hang ore belt was mainly sourced from regional magmatism with mantle contributions, whereas the sulfur and lead for the Pb–Zn mineralization was likely derived from the host sedimentary rocks and Proterozoic metamorphic basement rocks, respectively. The S and Pb isotopic data, combined with the geochemical signatures of mineralization-related porphyries, suggest that the Cu was sourced from the deeper levels along with mantle-derived magmas. In contrast, the Pb–Zn probably originated from the crust, with partial melting of the crystalline basement in the Cathaysia Block. Consequently, a three-stage genetic model is proposed to explain the ore-forming processes of the Qin–Hang Cu-polymetallic belt in South China.