云南腾冲火山区上部地壳三维地震速度层析成像   总被引：22，自引：3，他引：22  

楼海  王椿镛  皇甫岗  秦嘉政 《地震学报》2002,24(3):243-251

根据1999年腾冲火山区人工地震探测资料，用层析成像方法反演了腾冲火山区上地壳三维P波速度结构．层析成像结果显示出，在腾冲火山区下方的上地壳内存在明显的P波低速区，该低速区在地下7～8km深度，可能与上地壳内的岩浆囊或部分熔融体有关．层析结果还显示出低速区主体在热海地区的东北侧．地表附近的低速区可能是构造破裂发育地区形成了有利于深部热流体上升的通道，因此，在热海形成最活跃的地热显示．   相似文献   

云南干热河谷特色农业开发   总被引：4，自引：0，他引：4  

何永彬  朱彤  卢培泽 《山地学报》2002,20(4):445-449

云南是一个山原省份，河谷盆地是农业发展的最适宜地区，由于部份河谷盆地存在干热气候，坡在退化，生态环境恶化等自然障碍，以及受农业基础设施薄弱的制约，使得传统农业明显欠发达；同时干热河谷地区又具有光热与土地等自然资源优势条件，适宜发展特色作农业和反季节农业。在农业产业结构调整优化的发展形势下，需要开展区域特色农业建设以实现农业开发效益的提高和农业生态环境的改善，提出具体的分区开发方向和相关产业化措施。  相似文献   

遥感影像在六库城市地质灾害调查中的应用   总被引：1，自引：0，他引：1       下载免费PDF全文

蒋劲  杨世瑜 《江苏地质》2008,32(4):308-311

根据地质灾害的特点,以六库城区排路坝滑坡和芭蕉河泥石流两地为遥感影像判译地质灾害实例,提出了六库城市地质灾害遥感影像特征判译标志  相似文献   

Crustal Structural and Tectonic Evolution and Oil Prospect Evaluation in the Songpan-Zoigê Block          下载免费PDF全文

MA Yongsheng  FU Xiaoyue  WU Jingsheng  CHEN Gao  South Exploration  Development Company  Sinope  Guanshang  Kunming  Yunnan Tongji University  Siping Ro  Shanghai China University of Geosciences  Lumo Ro  Wuhan  Hubei 《《地质学报》英文版》2007,81(1):55-60

1 Introduction The Songpan-Zoigê Block (SRB) lies in the east of the Qinghai-Tibet Plateau. It is a triangle block confined and surrounded by three structure belts: the east Kunlun-west Qinling belt (EK-WQLB) to the north, the Sichuan Basin to the southeast and the Garzê-Litang-Jinsha River belt to the southwest. This block is also the joint part of three tectonic domains: the North China, South China and Qinghai-Tibet domains (Huang and Chen, 1987). The development and evolutio…  相似文献   

鲁西归来庄金矿床深部外围找矿前景          下载免费PDF全文

张英梅  张国权  陈昆明  安茂国  孟祥伟  刘超  谢丽丽  王茂争 《山东国土资源》2018,34(10)

鲁西地区归来庄金矿床找矿始于1987年初,历经"六进六出"的坚持不懈,探求金金属量34.8t,填补了鲁西地区无大型金矿的空白。近几年,山东省鲁南地质工程勘察院在归来庄金矿床深部及外围开展的勘查工作,扩大了归来庄主矿体的规模,并且证实归来庄主矿体沿F1构造蚀变带向深部尚未封闭,仍有良好找矿前景。目前归来庄金矿累计探明金金属量超过50t,是鲁西地区唯一的特大型金矿床。该文在系统分析以往成果资料基础上,系统归纳了归来庄主矿体地质特征,建立了铜石杂岩体周边多种金矿化类型"一体多型"成矿模式,指出了下步找矿方向:归来庄金矿床深部找矿仍以寻找隐爆角砾岩型为主,外围重点围绕"一带多区",争取早日实现铜石地区找矿新突破。  相似文献   

Carbon–oxygen isotopic covariations of calcite from Langdu skarn copper deposit,China: implications for sulfide precipitation     

Tao Ren  Xingchun Zhang  Runsheng Han  Baohong Hou 《中国地球化学学报》2015,(1):21-27

The Langdu skarn copper deposit in the Zhongdian area, Yunnan Province, China, has an average Cu grade of 6.49 %. The deposit is related to a porphyry intrusion(*216 Ma), which was emplaced in the Upper Triassic sedimentary rocks of the Tumugou and Qugasi Formations.At the Langdu skarn copper deposit, carbon and oxygen isotope ratios of fresh limestones(d18O = 3.0–5.6 % relative to V-SMOW; d13 C = 24.5–25.7 % relative to PDB)and partly altered limestones(d18O = 27–7.2 to-1.9 %;d13C = 11.8–15.2 %) indicated that the deposit was a typical marine carbonate source. Oxygen and carbon isotope values for calcites formed at different hydrothermal stages are-9.1 to 0.2 and 10.1–16.3 %, respectively. Moreover,the carbon–oxygen isotopic composition of an ore-forming fluid(d18O = 5.0–9.5 %, d13 C =-7.3 to-5.3 %) suggested the presence of magmatic water, which most likely came from the differentiation or melting of a homologous magma chamber. The deposition of Calcite I may arise from metasomatism in an open system with a progressively decreasing temperature.Later, the minerals chalcopyrite, pyrrhotite, quartz and Calcite II were precipitated due to immiscibility. Water–rock interaction could potentially be responsible for Calcite III precipitation in the post-ore stage.  相似文献   

鲁西铜石金矿田找矿成果及成矿机制探讨          下载免费PDF全文

张英梅  安茂国  孟祥伟  徐然  徐超  冯玺平  陈昆明 《山东国土资源》2021,37(7)

铜石金矿田为山东省鲁西地区重要的金矿集区,1989—1994年勘查评价的归来庄金矿床,被原地质矿产部定义为"新地区、新类型、新发现",更是改写了鲁西地区无大型金矿床的格局。近年来,铜石金矿田金矿找矿取得了可喜的成果,累计发现大型金矿床1处、中型金矿床1处、小型金矿床3处、金矿点10余处,已查明上表的金金属量近50吨,目前已经成为山东省继胶东之后的第二大黄金生产基地。区内发现的金矿床类型复杂多样,其成矿主要与中生代铜石杂岩体、断裂构造关系密切,具有优越的金矿成矿地质条件和较大的资源潜力。本文在系统总结、归纳分析不同类型矿床地质特征基础上,从成矿时代、成矿物质来源、成矿温度、矿化富集规律等方面对成矿机制进行了探讨,认为区内矿床属铜石潜火山中低温热液型金矿床。  相似文献   

磁对流湍流对太阳P模振动的影响(英文)     

毕少兰 《紫金山天文台台刊》2003,(2)

为了进一步探索太阳对流区的物理性质 ,我们利用高精度N的日震观测数据来研究太阳内部扰动磁场对低阶太阳P模振动的影响。对于一个时间相关的MHD湍流源 ,我们给出了导致频率变化的各种可能性。如果只考虑磁扰动的贡献 ,不同值的振动模的频率变化仅只是涨落磁场能谱的函数。我们发现频率的变化随着太阳内部磁场强度增加而变大 ,并且和太阳活动周期密切相关。我们的计算表明太阳磁活动导致的频率变化可达 0 .3μΗz。  相似文献   

RT Leonis Minoris： an Unstable W Ursae Majoris System with a Spotted Component     

Yu-Lan Yang  Qing-Yao LiuNational Astronomical Observatories  Yunnan Observatory  Chinese Academy of Sciences  Kunming  United Laboratory of Optical Astronomy  Chinese Academy of Sciences 《中国天文和天体物理学报》2004,4(6):553-562

Complete BV light curves of the W UMa type binary RT LMi are presented. From the observations, four times of minimum light were determined. Based on the new times of minimum light and those collected from the literature, changes in the orbital period of the system were found and analyzed with Kalimeris et al.'s method. The result shows that the orbital period possibly oscillates with a cycle of about 64 years and an amplitude of 1.2 × 10-6 days. The present CCD photometric observations reveal that the light curves are obviously asymmetrical, and show a positive O'Connell effect, while the light curves obtained in 1982 exhibit a negative O'Connell effect. The present light curves were analyzed by means of the latest version of the Wilson-Devinney code, which was also used to correct the photometric effects, including the distortion on the radial-velocity curves obtained by Rucinski et al. The following absolute dimensions have been derived: MI -1.28 ±0.08 M⊙, M2 = 0.48 ±0.06 M⊙, R1 = 1.28 ±0.06 R⊙,  相似文献   

Zircon Geochronology and Trace Element Geochemistry from the Xiaozhen Copper Deposit, North Daba Mountain: Constraints on Albitites Petrogenesis     

WANG Gang  WANG Zongqi  ZHANG Yingli  WANG Kunming 《《地质学报》英文版》2014,88(1):113-127

Albitite often accompanies with various metal and gem mineral deposits and a large number of occurrences have been reported globally, including the South Qinling orogen, China. The Xiaozhen copper deposit is a typical deposit in the North Daba Mountain area of the South Qinling orogen whose distribution is controlled by albitite veins and fractures. As there are few studies on the petrogenesis of albitite in Xiaozhen copper deposit, this paper focuses on the petrogenesis of albitite and its mineralization age. Detailed fieldwork and mineral microscopic observations initially suggest that albitite from the Xiaozhen copper deposit is igneous in origin. Further zircon trace element geochemistry studies indicate that these zircons have high Th/U ratios(0.5), low La content, high(Sm/La)N and Ce/Ce*values, and a strong negative Eu anomaly, which are commonly seen in magmatic zircons. The chondrite–normalized rare earth element(REE) patterns are consistent with magmatic zircons from throughout the world, and they fall within or near the field of magmatic zircons on discriminant diagrams. The calculated average apparent Ti–in–zircon temperature for young zircons is 780°C, consistent with magmatic zircon crystallization temperatures. Therefore, zircon geochemistry indicates that the albitite origin is magmatic. SIMS U–Pb dating on nine magmatic zircons yielded a concordia age of 154.8±2.2 Ma, which represents the formation of albitite and the metallogenic age. More importantly, it is consistent with the ages of Yanshanian magmatism and metallogenesis in the South Qinling orogen, so formation of the Xiaozhen copper deposit may be a closely related geological event.  相似文献