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1.
塔里木河流域2001年四源一干河川径流运行分析   总被引:7,自引:14,他引:7  
20 0 1年塔里木河流域四条源流出山口天然径流量计 2 6 6 .5× 10 8m3 ,比多年平均值多 40 .70×10 8m3 ,增加 18%.源流区在进入塔里木河干流前总耗水量为 2 2 0 .0× 10 8m3 ,与多年平均值比较多 43.4× 10 8m3 ,增加 2 4.6 %,而入塔里木河水量为 46 .48× 10 8m3 ,比多年平均 48.12× 10 8m3 减少1.6 4× 10 8m3 .塔里木河干流龙头站———阿拉尔站 2 0 0 1年年径流量为 45 .72× 10 8m3 ,接近多年均值 46 .0 0× 10 8m3 ,属平水年 .干流上游区间耗水量 2 4.77× 10 8m3 ,占阿拉尔站年径流量的 5 4.2 %;中游区间耗水量 18.94× 10 8m3 ,占阿拉尔站年径流量的 41.4%;下游区间耗水 2 .0 2 5× 10 8m3 (纯塔里木河水 ) ,仅占阿拉尔站年径流量的 4.4%.2 0 0 1年从开都河 孔雀河的博斯腾湖和塔里木河向下游绿色走廊的应急输水于 11月 16日水流到台特玛湖 ,从而结束了塔里木河下游近 30a干涸的历史 ,使下游绿色走廊恶化环境开始恢复 .  相似文献   

2.
达朝元  巫建华  杨东光  郭恒飞  牛子良  祝洪涛  周舰  于兵 《地质论评》2021,67(1):67020009-67020009
南窝铺铀矿床位于西拉木伦缝合带以南、康宝—围场—赤峰断裂带(华北北缘断裂带的一部分)以北的白乃庙加里东期岛弧带和华北古板块北缘海西期俯冲—碰撞带,属沽源—红山子铀成矿带北东段红山子—广兴铀成矿亚带的一个铀矿床,铀矿体赋存在额里图组安山岩—英安岩—流纹岩组合中。该组合中的英安岩SHRIMP锆石n(206Pb)/n(238U)加权平均年龄为268.1±2.5 Ma(N=15,MSWD=0. 85),结合安山质角砾凝灰岩的锆石U-Pb年龄为277.1±0.9 Ma,指示额里图组安山岩—英安岩—流纹岩的地质时代属早二叠世(乌拉尔世)—中二叠世(瓜德鲁普世)早期;英安岩SiO2=65. 49%~68.23%,K2O=1.83%~2.56%,Na2O=4.13%~5.01%,(K2O+Na2O)=5.96%~7.47%,K2O/Na2O=0.43~0.59,(FeO+Fe2O3)=3.13%~4.63%,MgO=1.25%~1.79%,在TAS图解上落入亚碱性系列英安岩区,在FAM图解上落入钙碱性系列范围,在SiO2—K2O图解上落入中钾钙碱性系列范围,在Na2O—K2O图解上落入I型花岗岩区;Al2O3=15. 74%~16. 77%,CaO=2. 87%~3. 59%,A/CNK=0. 95~1. 12(平均为1.04,<1.1),标准矿物刚玉(C)的含量为0~1.74%,平均为0.96%,指示源岩为I型岩浆岩;英安岩稀土元素总量低,富集轻稀土,Eu无明显负异常,ΣREE=76.5×10-6~95.4×10-6,(La/Yb)N=4.97~12.5(平均8.95),δEu=0.80~1.13(平均0.94),稀土配分模式为右倾型,与安第斯型钙碱性系列火山岩基本一致。英安岩明显富集大离子亲石元素Rb、Th、U、K、Sr等和亏损高场强元素Nb、Ta、P、Ti等,微量元素蛛网图与安第斯型钙碱性系列火山岩的形式一致,在Ce—SiO2、Al2O3—Ga图解上均落入I型花岗岩区,在Ta—Yb、Nb—Y构造环境判别图解上落入火山弧花岗岩区域(VAG)及同碰撞花岗岩(syn- COLG)交界处,在Rb—(Y+Nb)、Rb—(Yb+Ta)构造环境判别图解上落入火山弧花岗岩区域(VAG),指示英安岩形成于俯冲作用下的岛弧环境。南窝铺铀矿床英安岩地质时代、岩石系列和形成构造环境的确定,不仅证实了早二叠世—中二叠世早期额里图组是红山子—广兴铀成矿亚带一个新的赋矿层位,而且揭示了岛弧型安山岩—英安岩—流纹岩组合也赋存有与火山岩有关的热液型铀矿,为深入开展热液型铀矿成矿理论的研究和进一步扩大铀矿勘查范围提供了新的基础资料。  相似文献   

3.
云南曲靖盆地构造演化及其对生物气成藏条件的控制   总被引:1,自引:0,他引:1  
侯宇光  何生  唐大卿 《现代地质》2006,20(4):597-604
曲靖盆地是在云南省发现的具有工业价值生物气藏的第三系沉积盆地之一。利用二维地震测线结合地质和钻井等资料开展了详细的构造和沉积解释,对曲靖盆地的构造特征、盆地形成和演化进行了较为系统的综合研究,分析了构造演化对生物气成藏条件的控制作用。曲靖盆地的早—中渐新世的断陷阶段为大套湖相暗色泥岩(蔡家冲组)形成时期;渐新世晚期—上新世早期为盆地整体抬升萎缩阶段,避免了蔡家冲组有机质的大量消耗,保存了第四纪以来生物气成藏的有机物质;晚上新世的盆地坳陷阶段为茨营组含煤层系(次要气源岩)、储集层、盖层和岩性圈闭形成的主要时期;上新世末的压扭抬升萎缩阶段是断背斜和断鼻等构造圈闭和构造—岩性复合圈闭发育时期;第四纪盆地稳定沉降阶段为生物气聚集成藏时期。  相似文献   

4.
对采自江苏东海毛北地区 (中国大陆科学钻探先导孔附近 )的新鲜榴辉岩样品进行了岩石热导率的测定 ,初步查明了该区榴辉岩热导率随矿物组成的变化关系 ,探讨了岩石结构特征和温度变化对热导率的影响 .本次所测东海超高压榴辉岩的热导率介于 3 .2 2 2~ 3.716Wm-1·K-1之间并随岩石中 2种主要矿物的相对含量比而变化 ,随着榴辉岩中石榴石对绿辉石体积比 (VGrt/VOmp)的增加而降低 ,近似的函数关系满足K =3 .76 7- 0 .18× (VGrt/VOmp) .岩石中矿物分布的不均匀性和面状构造的发育对榴辉岩热导率的影响较大 ,由此产生的热导率各向异性可达近 10 % .温度是影响热导率的另外一个重要因素 .结合本次的实测资料和相应的热导率 -温度关系 ,建立了东海地区榴辉岩热导率随温度的变化关系方程K(T)=1/ ( 7.85× 10 -2 +6 .95× 10 -4 ×T) ,根据这一方程并结合东海地区的地热梯度资料推算了榴辉岩热导率随 5 0 0 0m钻孔深度的变化关系 ,推测东海地区科学钻探施工至 5 0 0 0m深度时 ,榴辉岩的热导率将比地表平均降低 2 4% .该成果为钻探测井资料的解释以及该区地热结构模型的建立提供了重要依据和约束资料 .  相似文献   

5.
Pongkor矿床属于浅成低温热液 Au- Ag矿床 ,金储量至少为 98t,平均品位为 16 .4× 10 -6;银储量10 2 6 t,平均品位 171.2× 10 -6.它是印尼新近发现的规模较大的 Au- Ag矿床 .冰长石 4 0 Ar/3 9Ar成矿年龄值为 2 .0 5± 0 .5Ma.矿床属于低硫化物浅成低温热液型 ,含有 4条主要的石英脉矿体 .石英脉主要位于火山构造凹陷 (破火山口 )的内缘 ,形成于爆破溶结凝灰岩的喷发 .该喷发产生了火山碎屑熔岩、火山砾及少量碎屑岩夹层 ,构成区内火山岩组合 ,不整合覆盖于中新世安山岩之上 .矿床矿体厚度较大 ,平均厚度为 4 .2 m,陡倾斜 ,由石英、方…  相似文献   

6.
贵州茂兰是研究森林覆盖下岩溶表层系统结构特征、运行规律的重要基地。本文初步研究了该地区碳迁移的若干特征 :(1)土壤剖面中CO2 浓度变化。秋、冬季土下CO2 浓度 ,5 0cm处始终高于 2 0cm处 ,而在春、夏季土壤剖面中CO2 浓度变化幅度大 ,2 0cm处的浓度时常高出5 0cm处。土下 2 0cm、 5 0cm处CO2 浓度在不同季节的变化趋势是夏季 (32 833× 10 - 6、 386 6 6× 10 - 6)春季 (2 4 4 16× 10 - 6,2 880 0× 10 - 6)秋季 (6 4 5 0× 10 - 6) ,142 16× 10 - 6>冬季 (3833× 10 - 6,8833× - 6) ,土下CO2 浓度变化趋势与温度和降雨量有较好的正相关关系。 2 0cm处的CO2 浓度变化与温度的相关系数r =0 89,与降雨量的相关系数r =0 70 ;5 0cm处的CO2 浓度变化与温度的相关系数r =0 6 9,与降雨量的相关系数r =0 6 6。 (2 )土壤呼吸释放CO2 的速率有类似的变化规律 :夏季为 339 6 8mg m- 2 h- 1、为 2 81 74mg m- 2 h- 1、秋季为 2 0 6 5 9mg m- 2 h- 1、冬季为 6 5 5 3mg m- 2 h- 1。年均排放量为 1 96kg m- 2 yr- 1。 (3)随水排泄HCO3 - 1是岩溶表层泉碳迁移的重要组分。表层泉水的HCO3 - 1浓度的季节变化与气温、月降雨量、土下 2 0cm处CO2浓度存在着负相关 ,其相关系数r =- 0 5 7、  相似文献   

7.
本文提出以P_(507)为固定相,盐酸为流动相的萃取色谱法把铈从溶液中分离出来,以偶氮氯瞵-mN与铈的高灵敏显色反应进行比色。本法灵敏度ε=7.8×10~4。实验部分色谱柱:φ8×120m/m 硅烷化硅球100—120目(上试一厂出品) P_(507)(上海有机化学所实验工厂) 偶氮氯膦-mN0.05%水溶液杂质洗除液:5%NH_4Cl,2%磺基水杨酸,1%抗坏血酸,调至pH2—3 铈、镧、镨标准液:用光谱纯的氧化铈、氧化镧、氧  相似文献   

8.
草滩沟群龙王沟组在北秦岭西段广泛出露,对研究秦岭早古生代构造演化具有重要意义。LA- ICP- MS锆石U- Pb同位素定年结果显示草滩沟群龙王沟组酸性凝灰岩的结晶年龄为457. 4±3. 8Ma。草滩沟群龙王沟组酸性凝灰岩富硅(SiO 2 =64. 55%~73. 07%)和碱(Na 2 O+K 2 O=5. 35%~8. 11%),低铝(Al 2 O 3 =13. 91%~16. 07%);轻稀土元素富集,重稀土元素亏损,具Eu负异常(δEu=0. 34~0. 86);富集Rb、Th等大离子亲石元素(LILE),亏损Nb、Ta、Ti等高场强元素(HFSE),具有较低的Nb/Ta比值和Mg # 值。以上显示,草滩沟群龙王沟组酸性凝灰岩具壳源特征,为地壳部分熔融结果。北秦岭造山带草滩沟群龙王沟组酸性凝灰岩和晚奥陶世—早志留世岩浆岩具弧岩浆岩特征,显示它们形成于俯冲环境。结合北秦岭造山带早古生代超高压变质带、岩浆岩分布以及草滩沟群沉积特征显示,早奥陶世北秦岭造山带还处于商丹洋的俯冲阶段。  相似文献   

9.
张金明  陈光庭  才航加 《地质论评》2022,68(4):2022082021-2022082021
新元古界青白口系其它大坂组是中祁连地块西段基底岩系之一,对研究中祁连地块元古宙地质构造演化具有重要意义。笔者等通过1∶5万区调工作在其它大坂组中发现了英安质晶屑岩屑凝灰岩夹层,并对凝灰岩进行了锆石U- Pb年代学、岩石地球化学研究。测年结果表明样品中锆石年龄主要分3组。结合区域地质资料,笔者等认为第一组锆石(1456~1524 Ma)和第二组锆石(1018~1021 M)为外来锆石或/碎屑锆石,分别为物源区中元古代早期Columbia超大陆裂解事件和Rodinia大陆聚合事件(格林威尔造山作用)在中祁连地块中的响应;第三组锆石(946~964 Ma)的n(206Pb)/n(238U) 加权年龄为958±3 Ma(MSWD=1.4),代表英安质凝灰岩的形成时代。岩石地球化学分析表明,其它大坂组英安质晶屑岩屑凝灰岩样品属于过铝质(A/CNK=1.37~1.75)、高钾(K2O>Na2O,K2O=4. 48%~4. 86%)、钙碱性(σ=0. 89~1. 26)火山岩,稀土总量为(149. 7~156. 4)×10-6,(La/Yb)N为10. 15~10. 61,具负Eu异常(δEu=0. 62~0. 63),富集K、Rb、Ba、Th等大离子亲石元素,亏损Nb、Ti等高场强元素,显示出与岛弧钙碱性火山岩相似的特点,形成于活动大陆边缘环境,是中祁连地块中—新元古代早期Rodinia超大陆形成地质事件的响应。  相似文献   

10.
在详细的地质调查和岩石学研究的基础上,对北羌塘盆地菊花山地区不整合于上三叠统肖茶卡组之上的那底岗日组火山岩进行了精确的SHRIMP锆石UPb定年研究。英安质凝灰岩的锆石UPb年龄为2251±14 Ma,这一年龄数据代表了菊花山地区晚三叠世火山沉积事件的时代。北羌塘盆地菊花山地区那底岗日组火山岩主要为英安质、安山质凝灰岩夹安山岩的组合。烧失量低的5件样品SiO2含量较高,介于6030%~6714%, A/CNK介于088~131,属偏铝质—过铝质岩石,安山岩Mg#为2085,凝灰岩具有更高的Mg#,介于3894~5698,所有样品均具有低的TiO2,介于038%~090%;样品的稀土元素总量较高,∑REE=9724×10-6~18189×10-6,轻重稀土分馏明显,(La/Yb)N=764~1624,具弱的Eu负异常,其δEu=066~098;安山岩与凝灰岩具有非常相似的微量元素蛛网图,表现为Rb、Ba、Th、K等大离子亲石元素(LILE)明显富集,而其他元素如Sr、P、Ti等明显亏损,虽然不相容微量元素总体上呈现出不同程度的富集,但Nb—Ta相对La和Th明显亏损;菊花山地区那底岗日组火山岩具有与中上地壳相似的高场强元素型式,暗示这些火山岩的来源可能与中—上地壳有关。〖KH2〗〖HTH〗  相似文献   

11.
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.  相似文献   

12.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.  相似文献   

13.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

14.
正The Kuqa depression deposited thick rock salt,which has a lower density than surrounding rocks.When salt bodies form a certain scale,obvious negative gravity anomalies can be detected in the surface.Therefore,gravitational method can quickly obtain the shape,plane distribution of deep-seated salt bodies and overall tectonic morphology of the basin.  相似文献   

15.
正1 Introduction The Pingluoba brine,which characterized as high concentration with sodium,potassium,boron,lithium,and rubidium,possess great development value.The main composition of the brine can be summarized to the  相似文献   

16.
正1 Introduction In the present paper,MgCl2·6H2O,FeCl3·6H2O,and CeCl3·6H2O were used as raw materials in the precipitationhydrothermal method to synthesize MgF eC e hydrotalcite.The effects of the Fe:Ce molar ratio on the composition,crystal structure,and thermal stability of hydrotalcite are examined.Energy-dispersive X-ray spectroscopy(EDS),X-  相似文献   

17.
正1 Introduction Crystallization is one of important unit operations in the chemical production process,which requires not only the crystal product with high purity and yield,but also the available particle size of the crystal products to ensure product quality.Crystallization process is affected by  相似文献   

18.
正Dear Authors and Readers:First of all,on behalf of the new Editorial Board,I would like to express our sincere appreciation for your continuing support of our journal.This journal,founded in 1922,is the oldest geological journal in China.As the flagship journal of the Geological Society of China,it has become more and more influential in earth sciences in China and beyond.The journal is now indexed by SCI,CA and more than 20 other databases,with an impact  相似文献   

19.
正20141283 Bai Daoyuan(Hunan Institute of Geological Survey,Changsha 410016,China);Zhong Xiang Nature,Origin and Tectonic Setting of Jinzhou Basin in the South Segment of Xuefeng Orogen(Geology in China,ISSN1000-3657,CN11-1167/P,40(4),2013,p.1079-1091,10 illus.,47 refs.)Key words:foreland basins,strike-slip faults,Hunan Province  相似文献   

20.
正20142093Chen Daohua(Guangzhou Marine Geological Survey,Guangzhou 510075,China);Diao Shaobo The Latest Progress of Geological Marine Testing Technology in China(Rock and Mineral Analysis,ISSN0254-5357,CN11-2131/TD,32(6),2013,p.850-859,105refs.)Key words:chemical analysis,China  相似文献   

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