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Regolith Geochemical Studies in Kimberlitic Terrain: A Case Study from Lattavaram Kimberlite Cluster, Eastern Dharwar Craton, Southern India
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作者 P.Ramesh CHANDRA PHANI M.SRINIVAS 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期191-,共1页
Utility of geochemistry in mineral exploration is known since more than half-a-century.In reconnaissance diamond exploration,regolith geochemistry is a well known tool worldwide and helps in distinguishing
关键词 Regolith Geochemical Studies in Kimberlitic Terrain rock southern india A Case Study from Lattavaram Kimberlite Cluster
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Palaeomagnetic and Rockmagnetic Behaviour of Dykes from Hyderabad Granitic Region, Part of Eastern Dharwar Craton, Southern India
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作者 B.Madhusudan RAO R.SANDHYA +1 位作者 M.R.GOUTHAM B.V.S.MURTHY 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期41-,共1页
The dykes intruding the Hyderabad Granitic Region(HGR)which forms the part of eastern Dharwar Craton extending between northern and northwestern margins of the Cuddapah Basin and western margin of the
关键词 southern india Part of Eastern Dharwar Craton Palaeomagnetic and Rockmagnetic Behaviour of Dykes from Hyderabad Granitic Region
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Phase equilibrium modeling of incipient charnockite formation in NCKFMASHTO and MnNCKFMASHTO systems:A case study from Rajapalaiyam,Madurai Block,southern India 被引量:4
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作者 Takahiro Endo Toshiaki Tsunogae +1 位作者 M.Santosh E.Shaji 《Geoscience Frontiers》 SCIE CAS 2012年第6期801-811,共11页
早期的 charnockites 在 mesoscopic 规模上代表 granulite 形成并且在在深外壳中理解液体过程收到了可观的注意。这里,我们在马杜赖·布洛克,在 Rajapalaiyam 从一个早期的 charnockite 地区报导新 petrological 数据南部的印度... 早期的 charnockites 在 mesoscopic 规模上代表 granulite 形成并且在在深外壳中理解液体过程收到了可观的注意。这里,我们在马杜赖·布洛克,在 Rajapalaiyam 从一个早期的 charnockite 地区报导新 petrological 数据南部的印度,并且基于矿物质阶段平衡建模和 pseudosection 分析讨论 petrogenesis。Rajapalaiyam 是在从的南部的印度的一个关键地区诊断矿物质集合为超离频温度(UHT ) 变态被报导了。对岩石是的 UHT 近似在我们在这报导的 Opx 免费的 Grt-Bt 片麻岩(Kfs +Pl +Qtz +Bt +Grt +Ilm + 山) 以内发生的 charnockite (Kfs +Qtz +Pl +Bt +Opx +Grt + Ilm ) 的补丁和透镜学习。矿物质平衡在 NCKFMASHTO 系统在 charnockitic 集合上当模特儿的申请产出 820 杯 ? 的一个磅范围 ?? 瑮湥楳敶瀠牡浡瑥牥 ?? 嘊湥慤丠癯 ? 汐瑵湯※ ? 牁 ? 慵傖悑 ??? 鎬?? 抑貮吗?? 展开更多
关键词 紫苏花岗岩 平衡模型 系统 印度 斜方辉石 案例 深部流体 渗透脱水
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Groundwater Flow Model for a Tannery Belt in Southern India
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作者 Nepal C. Mondal V. P. Singh S. Sankaran 《Journal of Water Resource and Protection》 2011年第2期85-97,共13页
The objective of this article is to develop a groundwater flow model for a tannery belt using Visual MOD-FLOW Premium 4.4 for analyzing groundwater velocity and its response to various pumping strategies in two stages... The objective of this article is to develop a groundwater flow model for a tannery belt using Visual MOD-FLOW Premium 4.4 for analyzing groundwater velocity and its response to various pumping strategies in two stages, viz., steady and transient conditions. The steady state model was calibrated for April 2001, whereas the transient model was employed to forecast groundwater flow under various pumping strategies. The results showed that the total groundwater abstraction was about 80.43% of the groundwater recharge, but 10.25% was used up by evapotranspiration. The groundwater velocity, which is important for contaminant migration, varied from 0.21 to 0.52 m/d in the tannery cluster. The model was more sensitive to recharge from rainfall, hydraulic conductivity and specific yield. Finally, the model showed that the aquifer could sustain a pumping rate of 24892 m3/day without further decline in water level. 展开更多
关键词 GROUNDWATER Flow Model GROUNDWATER VELOCITY TANNERY BELT southern india
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Clinical exome sequencing facilitates the understanding of genetic heterogeneity in Leber congenital amaurosis patients with variable phenotype in southern India 被引量:1
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作者 Sriee Viswarubhiny Rupa Anjanamurthy +3 位作者 Ayyasamy Vanniarajan Devarajan Bharanidharan Vijayalakshmi Perumalsamy Periasamy Sundaresan 《Eye and Vision》 SCIE CSCD 2021年第1期192-202,共11页
Background:Leber congenital amaurosis(LCA),primarily characterized by retinal degeneration is the most severe form of inherited retinal dystrophy(IRD)responsible for congenital blindness.The presence of phenotypic het... Background:Leber congenital amaurosis(LCA),primarily characterized by retinal degeneration is the most severe form of inherited retinal dystrophy(IRD)responsible for congenital blindness.The presence of phenotypic heterogeneity makes the diagnosis of LCA challenging,especially in the absence of pronounced disease pathognomonic,yet it can be well comprehended by employing molecular diagnosis.Therefore,the present study aimed to reveal the causative mutations in ten LCA patients with variable phenotypes using clinical exome sequencing(CES).Methods:CES was performed in ten unrelated LCA patients.Ophthalmic information and family history of all patients were obtained to make a meaningful interpretation.The clinical exome data was analyzed and prioritized using a bioinformatics pipeline to identify mutations,which was further validated by Sanger sequencing.Segregation analysis was also performed on available family members.Results:CES led to the identification of causative mutations in nine LCA patients.Seven patients harbored a mutation in six LCA candidate genes,including RPE65,LCA5(n=2),CRX,PRPH2,CEP290,and ALMS1,while two patients possess a mutation in IFT80 and RP1,known to cause other diseases.Three novel mutations in LCA5(c.1823del),CRX(c.848del)and CEP290(c.2483G>T)were identified.The current study reports for the first time,a mutation in PRPH2,CEP290,and ALMS1 from the Indian population.Additionally,we observed a novel association of LCA phenotype with IFT80 known to cause Jeune syndrome.Based on the genetic finding,the patient AS09,who harbored a mutation in the RP1 gene,was re-diagnosed with early-onset retinitis pigmentosa.Conclusion:In conclusion,the results underline the importance of CES in clinically diagnosed LCA patients with variable phenotypes.The correlation between mutations in candidate genes and clinical phenotypes,helps to refine the clinical diagnosis.However,molecular evaluation with a larger cohort of LCA patients is needed for better understanding of the mutational spectrum in southern India. 展开更多
关键词 Leber congenital amaurosis Clinical exome sequencing southern india Molecular diagnosis Genotype-phenotype correlation
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Early Eocene Radiolarian Fauna from the Sangdanlin, Southern Tibet: Constraints on the Timing of Initial India-Asia Collision 被引量:9
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作者 WANG Tianyang LI Guobiao +1 位作者 LI Xinfa NIU Xiaolu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第6期1964-1977,共14页
This is a new report on the early Eocene radiolarian fauna from the Sangdanlin section in the Gyirong region, along the southern margin of the Yarlung Zangbo Suture Zone. The Sangdanlin section measured in this study ... This is a new report on the early Eocene radiolarian fauna from the Sangdanlin section in the Gyirong region, along the southern margin of the Yarlung Zangbo Suture Zone. The Sangdanlin section measured in this study is divided into three lithostratigraphic units from bottom to top: the Zongzhuo, Sangdanlin, and Zheya formations. Abundant radiolarian fossils were obtained from the Sangdanlin section and 54 species of 30 genera were identified and assigned as follows: Cryptamphorella conara-C. macropora the late Cretaceous Zone and Amphisphaera coronate, Buryella tetradica-Bekoma campechensis, and B.bidartensis-B. divaricata the Paleocene-early Eocene Interval Zones. The Paleocene–early Eocene radiolarian zones are comparable to the radiolarian zones RP4-RP8 in New Zealand. Based on the data of radiolaria and lithofacies, it is suggested that the Zongzhuo Formation should be deposited along the base of the north-facing, continental slope of the Greater Indian continental margin, and the Sangdanlin Formation should be a deep marine, sedimentary sequence located in a foreland basin. The early Eocene radiolarian fauna in the Sangdanlin Formation constrains the initial age of the India-Asia collision to no later than 53.6 Ma. 展开更多
关键词 放散虫类的各类动物 始新世 印度亚洲碰撞 NEO-TETHYS 南部的西藏
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Southern and Tropical Indian Ocean SST: A Possible Predictor of Winter Monsoon Rainfall over South India
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作者 Ravi P. Shukla Shailendra Rai Avinash C. Pandey 《Atmospheric and Climate Sciences》 2013年第4期440-449,共10页
The complexities in the relationship between winter monsoon rainfall (WMR) over South India and Sea Surface temperature (SST) variability in the southern and tropical Indian Ocean (STIO) are evaluated statistically. T... The complexities in the relationship between winter monsoon rainfall (WMR) over South India and Sea Surface temperature (SST) variability in the southern and tropical Indian Ocean (STIO) are evaluated statistically. The data of the time period of our study (1950-2003) have been divided exactly in two halves to identify predictors. Correlation analysis is done to see the effect of STIO SST variability on winter monsoon rainfall index (WMRI) for South India with a lead-lag of 8 seasons (two years). The significant positive correlation is found between Southern Indian Ocean (SIO) SST and WMRI in July-August-September season having a lag of one season. The SST of the SIO, Bay of Bengal and North Equatorial Indian Ocean are negatively correlated with WMRI at five, six and seven seasons before the onset of winter monsoon. The maximum positive correlation of 0.61 is found from the region south of 500 S having a lag of one season and the negative correlations of 0.60, 0.53 and 0.57 are found with the SST of the regions SIO, Bay of Bengal and North Equatorial Ocean having lags of five, six and seven seasons respectively and these correlation coefficients have confidence level of 99%. Based on the correlation analysis, we defined Antarctic Circumpolar Current Index A and B (ACCIA (A) & ACCIB (B)), Bay of Bengal index (BOBI (C)) and North Equatorial Index (NEI (D)) by averageing SST for the regions having maximum correlation (positive or negative) with WMRI index. These SST indices are used to predict the WMRI using linear and multivariate linear regression models. In addition, we also attempted to detect a dynamic link for the predictability of WMRI using Nino 3.4 index. The predictive skill of these indices is tested by error analysis and Willmott’s index. 展开更多
关键词 Winter MONSOON RAINFALL OVER South india southern/Tropical indian Ocean Multivariate/Linear Regression Models
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Positioning the Southern Margin of Asia Prior to Its Collision with India: Paleomagnetic Constraints from Late Cretaceous Dykes in Gangdise Belt
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作者 YI Zhiyu MA Xuxuan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期50-,共1页
The pre-collisional southern margin of Asia can be restored using paleomagnetic data from late Cretaceous rocks from the Lhasa terrane.However,the available data are based either on the red beds or on the intercalated... The pre-collisional southern margin of Asia can be restored using paleomagnetic data from late Cretaceous rocks from the Lhasa terrane.However,the available data are based either on the red beds or on the intercalated thin layers of lava flows,both of which had been involved in strongly folding.Recent studies show clear evidence for the possibility of serious overprint hence the data could not be reliably used for tectonic interpretation.We report paleomagnetic data from diorite dykes and the grano-diorite country rock in the Gandise belt near the city of Lhasa.U–Pb isotopic dating indicates the intrusive rocks have an age of^82–86 Ma.Fifteen sites yield acceptable Ch RM directions which pass a reversal test.SEM and light microscope observations show primaryintergrowth relationship between magnetite and other minerals within the thin sections.AMS measurement defines a primary magma flow fabric for the intruded dykes and the country rocks.All the characteristics support that the Ch RMs are primary.The paleomagnetic pole calculated from the remanence of the dykes and the country rocks yields a paleolatitude of^14°N which provide a reliable constraint for the southern margin of Asia near Lhasa.Furthermore,the recorded declination shows significant counterclockwise rotation of^20°for the sampling location relative to the north.In consideration of the strike and tectonic setting of the dykes,the strike of the southern margin of Asia is restored which is compatible with the hypothesis of a quasi-linear margin of Eurasia prior to its collision with India. 展开更多
关键词 ASIA Positioning the southern Margin of Asia Prior to Its Collision with india Paleomagnetic Constraints from Late Cretaceous Dykes in Gangdise Belt
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Climatic periodicities recorded in lake sediment magnetic susceptibility data:Further evidence for solar forcing on Indian summer monsoon 被引量:3
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作者 Anish Kumar Warrier Kizhur Sandeep Rajasekharaiah Shankar 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第6期1349-1355,共7页
The Indian summer monsoon exhibits considerable spatio-temporal variability.It is therefore important to understand its dynamics and the inherent periodicities.In this study,we have performed spectral and wavelet anal... The Indian summer monsoon exhibits considerable spatio-temporal variability.It is therefore important to understand its dynamics and the inherent periodicities.In this study,we have performed spectral and wavelet analyses of magnetic susceptibility data for sediments from Thimmannanayakanakere(TK)-a small lake in southern India.The main objective of this investigation is to identify and explain the possible origin of the prominent periodicities present in the magnetic susceptibility data.Significant periodicities in the TK χ_(lf)data are centered at 906,232,147,128,96,61,54 and 44 years,which might have a solar origin.The wavelet power spectrum of the raw and detrended χ_(lf)data confirms the findings of spectral analysis and also provides temporal variations of the significant cyclicities during the past3700 cal.years B.P.Positive correlation is documented between sunspot activity and TK xif data;crossspectral analysis of the reconstructed sunspot data and TK xif data suggest that there is a strong coherence between the two datasets as significant periodicities are documented in both.There is a good match between the TK xif and the reconstructed total solar irradiance data for the past 1200 years.However,an out-of-phase relationship is documented at certain time-intervals,which may be attributed to uncertainties in the age-depth model.The results obtained from this study show that solar variations are the main controlling factor of the southwest monsoon and,like other archives from different regions in India,the TK lake sediments have also recorded these solar signatures. 展开更多
关键词 Spectral analysis PERIODICITY Paleorainfall Lake SEDIMENTS Magnetic susceptibility southern india
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Ceftazidime resistance in Burkholderia pseudomallei:First report from India 被引量:3
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作者 Bijayini Behera TLVD Prasad Babu +1 位作者 A Kamalesh Gangadhar Reddy 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2012年第4期329-330,共2页
Melioidosis,a disease of public health importance in Southeast Asia and Northern Australia,of late has shown an increasing trend in India,particularly Southern India.We describe a ease of a 39-year-old diabetic patien... Melioidosis,a disease of public health importance in Southeast Asia and Northern Australia,of late has shown an increasing trend in India,particularly Southern India.We describe a ease of a 39-year-old diabetic patient with left elbow septic arthritis,multiple liver,splenic abscesses, pneumonia,pleural effusion,followed by sepsis syndrome.Blood cultures and culture of the joint aspirate yielded pure growth of Burkholderia psettdomallei(B.pesudomallei),sensitive to carbapenem,co-trimoxazole and resistant to ceftazidime.The patient was successfully treated with imipenem- cilastin.He was discharged on co-trimoxazole to complete the 24 weeks course and follow-up has continued to date.The patient continues to remain asymptomatic.The case re-emphasizes the need to monitor the trend of B.pseudomallei in India,particularly the development of ceftazidime resistance,which incidentally is the drug of choice. 展开更多
关键词 MELIOIDOSIS BURKHOLDERIA pseudomallei southern india CEFTAZIDIME Carbapenem Diabetes MELLITUS
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A geochemical perspective on charnockite magmatism in Peninsular India 被引量:7
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作者 H.M.Rajesh 《Geoscience Frontiers》 SCIE CAS 2012年第6期773-788,共16页
大 charnockite 山岳发生在高级南部的 Granulite 地面(SGT ) 和东方 Ghats 带(EGB ) 半岛的印度的外壳的省。可得到的 geochronological 数据显示 magmatism 是阵发性的,在不同的外壳的域与不同 orogenic 周期联系了。geochemical 数... 大 charnockite 山岳发生在高级南部的 Granulite 地面(SGT ) 和东方 Ghats 带(EGB ) 半岛的印度的外壳的省。可得到的 geochronological 数据显示 magmatism 是阵发性的,在不同的外壳的域与不同 orogenic 周期联系了。geochemical 数据也在 3.02.9 Ga 从 trondhjemitic 在作文显示一个变化到主导地在到在 2.01.9 Ga 到的 tonalitic-granodiorite-granitic 的 2.62.5 Ga 的 tonalitic 主导地在到石英 monzonitic 的 1.71.6 Ga 的 tonalitic 或在 1.00.9 Ga 到的 tonalitic 在 0.80.7 Ga granodiorite 花岗石。trondhjemitic 和 tonalitic 结束成员是 metaluminous,对 calc-alkalic 镁、钙,镁的组 charnockites 特征。到花岗石的结束成员的 granodioritic 是 metaluminous 到稍微 peraluminous, ferroan 和 calc-alkalic 到碱钙, ferroan 组 charnockites 特征。石英 monzonitic 结束成员是到 peraluminous 的 metaluminous,对 ferroan 镁、对 calc-alkalic 钙,镁的组也不 charnockites 的 ferroan 组的两个特征。在 charnockite 山岳的作文基于出现和差别, charnockite magmatism 登记印度板的外壳的生长在上,这被建议它的南部(SGT ) 并且东方(EGB ) 站在一起,由弧的生长的活跃大陆人边缘。 展开更多
关键词 紫苏花岗岩 地球化学数据 印度半岛 岩浆作用 花岗闪长岩 同位素年代学 地壳生长 活动大陆边缘
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Role of the Subtropical Westerly Jet Waveguide in a Southern China Heavy Rainstorm in December 2013 被引量:15
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作者 LI Chun SUN Jilin 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第5期601-612,共12页
An extreme rainstorm hit southern China during 13–17 December 2013, with a record-breaking daily rainfall rate, large spatial extent, and unusually long persistence. We examined what induced this heavy rainfall proce... An extreme rainstorm hit southern China during 13–17 December 2013, with a record-breaking daily rainfall rate, large spatial extent, and unusually long persistence. We examined what induced this heavy rainfall process, based on observed rainfall data and NCEP–NCAR reanalysis data through composite and diagnostic methods. The results showed that a Rossby waveguide within the subtropical westerly jet caused the event. The Rossby wave originated from strong cold air intrusion into the subtropical westerly jet over the eastern Mediterranean. With the enhancement and northward shift of the Middle East westerly jet, the Rossby wave propagated slowly eastward and deepened the India–Burma trough, which transported a large amount of moisture from the Bay of Bengal and South China Sea to southern China. Strong divergence in the upper troposphere, caused by the enhancement of the East Asian westerly jet, also favored the heavy rainfall process over Southeast China. In addition, the Rossby wave was associated with a negative-to-positive phase shift and enhancement of the North Atlantic Oscillation, but convergence in the eastern Mediterranean played the key role in the eastward propagation of the Rossby wave within the subtropical westerly jet. 展开更多
关键词 副热带西风急流 中国南方 大暴雨 波导 ROSSBY波 地中海东部 中国东南地区 北大西洋涛动
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亚欧典型热浪过程的大气环流对比分析 被引量:15
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作者 孙国武 汤绪 +1 位作者 刘新伟 梁萍 《高原气象》 CSCD 北大核心 2007年第3期503-510,共8页
使用探空站实测资料、国家气象中心500 hPa位势高度和NCEP/NCAR再分析资料,分析了中国西北和江南地区以及欧洲、印度发生的典型热浪过程及其形成热浪的大气环流系统。结果表明:西风带高压脊和副热带高压的同位相“南北叠加”(表明高压宽... 使用探空站实测资料、国家气象中心500 hPa位势高度和NCEP/NCAR再分析资料,分析了中国西北和江南地区以及欧洲、印度发生的典型热浪过程及其形成热浪的大气环流系统。结果表明:西风带高压脊和副热带高压的同位相“南北叠加”(表明高压宽广)和低层高压与上层高压的同位相“上下叠加”(表明高压深厚),以及下沉运动和感热、潜热中心的分布,是中国西北和欧洲热浪形成的大气环流原因;而中国江南和印度的热浪,则与副热带高压的异常强大和夏季风活动有关。 展开更多
关键词 热浪 大气环流 中国西北 中国江南 欧洲 印度
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冈底斯弧的岩浆作用:从新特提斯俯冲到印度-亚洲碰撞 被引量:15
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作者 张泽明 丁慧霞 +1 位作者 董昕 田作林 《地学前缘》 EI CAS CSCD 北大核心 2018年第6期78-91,共14页
位于青藏高原南部的冈底斯岩浆弧形成于中生代新特提斯大洋岩石圈的长期俯冲过程中,而且在印度与亚洲大陆碰撞过程中叠加了强烈的新生代岩浆作用,是世界上典型的复合型大陆岩浆弧,已经成为研究汇聚板块边缘岩浆作用和大陆地壳生长与再... 位于青藏高原南部的冈底斯岩浆弧形成于中生代新特提斯大洋岩石圈的长期俯冲过程中,而且在印度与亚洲大陆碰撞过程中叠加了强烈的新生代岩浆作用,是世界上典型的复合型大陆岩浆弧,已经成为研究汇聚板块边缘岩浆作用和大陆地壳生长与再造的天然实验室。基于对现有研究成果的总结,我们将冈底斯岩浆弧的岩浆构造演化划分为5个阶段:第1阶段发生在晚白垩世之前,以新特提斯洋岩石圈长期正常俯冲和钙碱性弧岩浆岩的发育为特征;第2阶段发生在晚白垩世时期,以活动的新特提斯洋中脊发生俯冲和强烈的岩浆作用与显著的新生地壳生长为特征;第3阶段发生在晚白垩世晚期,以残余的新特提斯大洋岩石圈俯冲和正常弧型岩浆作用为特征;第4阶段发生在古新世至中始新世,以印度与亚洲大陆碰撞、俯冲的新特提斯洋岩石圈回转和断离,及其诱发的幔源岩浆作用、新生和古老地壳的强烈再造为特征;第5阶段为发生在晚渐新世到中中新世的后碰撞阶段,深俯冲印度岩石圈的回转和断离,或加厚岩石圈地幔的对流移去导致了加厚下地壳的部分熔融和埃达克质岩石的广泛发育,同时伴随幔源钾质超钾质岩浆作用。冈底斯弧岩浆作用与岩浆成分的系统时空变化很好地记录了从新特提斯洋俯冲到印度亚洲大陆碰撞的完整构造演化过程。 展开更多
关键词 冈底斯弧岩浆作用 新特提斯洋俯冲 印度-亚洲大陆碰撞 青藏高原南部
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碰撞前印度大陆北缘古地理轮廓——藏南晚白垩世堆拉灰岩古地磁研究 被引量:3
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作者 易治宇 梁雅伦 +3 位作者 赵杰 闫永刚 陈力为 唐祥德 《地质学报》 EI CAS CSCD 北大核心 2016年第11期3282-3292,共11页
堆拉灰岩的古地磁数据为重建碰撞前印度大陆北缘轮廓提供了重要制约,但也留下了一些疑点,为此,本文对该地区晚白垩世海相沉积开展了进一步的古地磁研究。通过对10个采点样品的系统退磁及统计分析,得到宗山组最下段经地层校正后的特... 堆拉灰岩的古地磁数据为重建碰撞前印度大陆北缘轮廓提供了重要制约,但也留下了一些疑点,为此,本文对该地区晚白垩世海相沉积开展了进一步的古地磁研究。通过对10个采点样品的系统退磁及统计分析,得到宗山组最下段经地层校正后的特征剩磁分量为D=168.2°,I=-7.3°,α95=7.5°。该分量与前人从该地区宗山组中、上段得到的古地磁结果无显著区别,并在95%的置信水平上通过褶皱检验,表明剩磁是褶皱前获得的。尽管如此,堆拉晚白垩世灰岩统一的负极性特征与其沉积期间(Turonian-Maastrichtian)对应的古地磁标准极性柱不符,表明该地区宗山组不同层位可能普遍遭遇了重磁化,不能用来约束喜马拉雅地体的古地理位置。基于以上考虑,本文仅用前人从岗巴宗山地区获得的古地磁结果对晚白垩世期间特提斯喜马拉雅地体的古地理位置进行了计算和修正,结果显示该地体在宗山组上段沉积期间(约71~65Ma)的古纬度约为9°S,计算得到当时大印度的北向延伸量为1500km,与前人从宗浦组得到的古地磁结果一致。 展开更多
关键词 印度-亚洲碰撞 古地磁 古地理重建 藏南 白垩纪
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藏南白垩纪—古近纪岩石地层厘定与构造地层划分 被引量:10
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作者 胡修棉 李娟 +1 位作者 安慰 王建刚 《地学前缘》 EI CAS CSCD 北大核心 2017年第1期174-194,共21页
岩石地层的厘定是一件基础而重要的工作,集中体现了一个阶段对地层的综合认识水平;对一个地区而言,建立行之有效的岩石地层划分方案具有重要的意义。文中详细介绍和评述了藏南白垩纪—古近纪(含中新世)33个岩石地层单元,其中特提斯喜马... 岩石地层的厘定是一件基础而重要的工作,集中体现了一个阶段对地层的综合认识水平;对一个地区而言,建立行之有效的岩石地层划分方案具有重要的意义。文中详细介绍和评述了藏南白垩纪—古近纪(含中新世)33个岩石地层单元,其中特提斯喜马拉雅南带13个、特提斯喜马拉雅北带9个、日喀则弧前盆地带9个、雅鲁藏布缝合带2个。特提斯喜马拉雅南带白垩系包括古错村组、东山组、察且拉组、冷青热组、波林夏拉组、岗巴村口组、旧堡组、遮普惹山坡组、宗山组;古近系包括基堵拉组、宗浦组、恩巴组、扎果组;特提斯喜马拉雅北带白垩系包括维美组、日朗组、甲不拉组、床得组;古近系包括宗卓组、甲查拉组、蹬岗组、桑单林组、者雅组;日喀则弧前盆地带白垩系包括桑祖岗组、昂仁组、帕达那组、曲贝亚组,古近系包括曲下组、加拉孜组、达金组;中新统包括秋乌组、大竹卡组;雅鲁藏布缝合带包括白垩系冲堆组、渐新统—中新统柳区群。文中在结合物源分析、盆地演化等研究资料基础上,划分了7个构造地层单元:其中印度-亚洲大陆碰撞后的新生代2个(TS1、TS2)、碰撞前白垩纪印度北缘3个(TSI3、TSI4、TSI5)、亚洲南缘2个(TSL3、TSL4)。 展开更多
关键词 西藏南部 喜马拉雅 岩石地层 构造地层 白垩纪 古近纪 雅鲁藏布缝合带 印度-亚洲大陆碰撞
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塔里木盆地南部塘古孜巴斯坳陷发现晚新生代伸展构造 被引量:6
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作者 杨素举 马庆佑 +9 位作者 李曰俊 黄太柱 吕海涛 文磊 张强 孟庆龙 陈跃 赵岩 贾铁干 赵甜玉 《地质科学》 CAS CSCD 北大核心 2017年第2期317-327,共11页
通过认真、系统的地震资料解释,在塔里木盆地南部的塘古孜巴斯坳陷及周缘首次发现晚新生代正断层。在塘古孜巴斯坳陷内部发现的晚新生代正断层走向为北西-南东向,剖面上组合成地堑或堑一构造,与巴楚隆起东北缘所发育的晚新生代正断... 通过认真、系统的地震资料解释,在塔里木盆地南部的塘古孜巴斯坳陷及周缘首次发现晚新生代正断层。在塘古孜巴斯坳陷内部发现的晚新生代正断层走向为北西-南东向,剖面上组合成地堑或堑一构造,与巴楚隆起东北缘所发育的晚新生代正断层相似。塘古孜巴斯坳陷西北缘发现的两条晚新生代正断层走向为北东-南西,剖面组合成一地堑构造,与阿瓦提凹陷西北缘沙井子断裂带上发育的晚新生代张扭性正断层带走向一致,但不具备张扭性变形特征。正断层形成于上新世晚期(约3Ma),持续演化至更新世早期(约2Ma)。正断层的活动时间也与阿瓦提凹陷周缘的晚新生代正断层一致。它们形成于一个区域性弱伸展构造应力场内,代表印度-亚洲碰撞远程效应下,塔里木盆地脉式挤压(一冲断)过程中的一个构造间歇期。 展开更多
关键词 晚新生代 正断层 印度-亚洲碰撞远程效应 构造间歇期 塘古孜巴斯坳陷 里木盆地南部
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藏南定日地区晚白垩世古近纪地层和盆地演化:对印度和亚洲初始碰撞时间的暗示(英文) 被引量:7
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作者 Hugh D.SINCLAIR 《地球学报》 EI CAS CSCD 北大核心 2012年第S1期21-22,共2页
This is an extended abstract of Hu et al.,2012. The timing of the initial collision between India and Asia remains a matter of considerable debate,with views ranging from~70 Ma to~35 Ma.Here the initial India-Asia c... This is an extended abstract of Hu et al.,2012. The timing of the initial collision between India and Asia remains a matter of considerable debate,with views ranging from~70 Ma to~35 Ma.Here the initial India-Asia contact is defined as the time at which the 展开更多
关键词 STRATIGRAPHY basin analysis CRETACEOUS PALEOGENE southern Tibet india-Asia COLLISION
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印度南部麻粒岩地体Namakkal陆块新太古代钙硅酸盐岩的岩石学和锆石U-Pb年代学研究
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作者 周峰 苟龙龙 +5 位作者 翟明国 张成立 GORGE Paul Mathews 卢俊生 赵燕 敖文昊 《岩石学报》 SCIE EI CAS CSCD 北大核心 2021年第4期1213-1234,共22页
本文对印度南部麻粒岩地体Namakkal陆块Tammampatti地区方柱石石榴子石钙硅酸盐岩进行了详细的岩石学、锆石U-Pb年代学和变质相平衡模拟研究,以研究其岩石成因和地质意义。岩相学观察识别出两阶段变质矿物组合:第一阶段为石榴子石+方柱... 本文对印度南部麻粒岩地体Namakkal陆块Tammampatti地区方柱石石榴子石钙硅酸盐岩进行了详细的岩石学、锆石U-Pb年代学和变质相平衡模拟研究,以研究其岩石成因和地质意义。岩相学观察识别出两阶段变质矿物组合:第一阶段为石榴子石+方柱石+斜长石+榍石+钛铁矿;第二阶段为石榴子石边部的绿帘石和方柱石边缘的方解石、斜长石和石英冠状体。CL图像分析显示锆石可分为两种,分别为高亮度和低亮度的变质锆石。LA-ICP-MS锆石U-Pb定年得到高亮度变质锆石^(207)Pb/^(206)Pb加权平均年龄为2562±17Ma,而低亮度变质锆石的^(207)Pb/^(206)Pb加权平均年龄稍年轻,为2495±15Ma。基于相平衡模拟计算了2个样品18ID-24和18ID-25的P-T视剖面图,确定它们峰期变质PT条件分别为4.3~7.1kbar、800~960℃和4.0~7.8kbar、750~854℃。高亮度变质锆石年龄2562±17Ma与Namakkal陆块紫苏花岗岩的原岩结晶年龄相当,其代表了紫苏花岗岩的原岩侵入导致的接触交代变质作用形成方柱石石榴子石钙硅酸盐岩的时代;低亮度变质锆石年龄2495±15Ma与该地区大约2530~2440Ma的高温-超高温变质作用时代相吻合,因此认为其代表区域性变质作用叠加的时代。根据全岩成分以及矿物组合,我们推测该岩石为中酸性岩浆岩(紫苏花岗岩原岩)与碳酸盐岩发生交代变质作用的产物。 展开更多
关键词 方柱石石榴子石钙硅酸盐岩 相平衡模拟 紫苏花岗岩 交代变质作用 印度南部麻粒岩地体
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Hydrodynamic modeling along the southern tip of India: A special emphasis on Kanyakumari coast 被引量:2
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作者 K.Gurumoorthi R.Venkatachalapathy 《Journal of Ocean Engineering and Science》 SCIE 2017年第4期229-244,共16页
Hydrodynamic models are important to many coastal engineering designs and application,especially addressing sediment and water quality.In this study,MIKE 21 two-dimensional(2D)hydrodynamic model based on the flexible ... Hydrodynamic models are important to many coastal engineering designs and application,especially addressing sediment and water quality.In this study,MIKE 21 two-dimensional(2D)hydrodynamic model based on the flexible mesh(FM)technique was used to simulate the surface currents forced by tides and winds in Kanyakumari coast.The model results of the tidal level along shore and cross shore currents are agreed well with measured data in Kanyakumari coast.The major components of tides and currents are analyzed by harmonic analysis methods.Root mean square error(RMSE)values for the measured and model tides(0.017 m and 0.079 m)and currents(0.025 m/s and 0.009 m/s)during the northeast(NE)and southwest(SW)monsoon period are calculated.A series of scenario runs for NE and SW monsoon season are used to understand the regional circulation.The model result shows that the Kanyakumari coast is dominated by tides and surface currents flow,which are influenced by the seasonal reversal wind pattern.Flows around this coastal water have been evidenced small scale cyclonic and anti-cyclonic eddies ranged from∼55 to 120 km in diameter.The cyclonic and anti-cyclonic eddies are mostly appeared in near Kanyakumari and SE coast of Kerala due to local/remotely generated forces. 展开更多
关键词 Hydrodynamic model TIDE Surface circulation EDDY Kanyakumari southern tip of india
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