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Analysis of the Causes of the Intensity Enhancement of the Typhoon “Tiange”
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作者 Yiqin Deng Xin Qi +1 位作者 Zhewei Deng Rong Huang 《Journal of Geoscience and Environment Protection》 2023年第7期156-164,共9页
This paper analyzes the causes of the offshore strength enhancement of Typhoon Tiange (No. 1713) from four aspects: high and low layer divergence, vertical wind shear, southwest monsoon transport, offshore sea tempera... This paper analyzes the causes of the offshore strength enhancement of Typhoon Tiange (No. 1713) from four aspects: high and low layer divergence, vertical wind shear, southwest monsoon transport, offshore sea temperature and weak cold air. The conclusions are as follows: The high-level airflow divergence enhancement and positive vorticity advection in the offshore, strengthen the middle rise movement of the “Tiange”, and the ascending movement enhances the strength of the “Tiange” by strengthening the lower layer convergence;The high offshore sea temperature and sea temperature are changing temperature, which also has a certain effect on the strengthening of “Tiange” in the offshore;The strengthening of the southwest warm and humid airflow provides sufficient water vapor and energy for the development of “Tiange”, which is beneficial to the maintenance of the typhoon warm heart structure;The intrusion of weak cold air, enhanced the radiation cooperation of the lower typhoon disturbance, which is beneficial to the enhancement of “Tiange”. 展开更多
关键词 TYPHOON offshore Strengthening cause analysis
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Provenance of Conglomerate and Sandstone from Early Permian Shoushangou Formation in Xi Ujimqin,Inner Mongolia:Implications for Understanding Paleo-Asian Ocean Subduction
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作者 ZHANG Yingli GUO Xianqing MA Shouxian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期10-31,共22页
During the Late Carboniferous to Early Permian,a rift was formed by post-collisional extension after ocean closure or an island arc-related basin formed by Paleo-Asian Ocean(PAO)subduction in the Xi Ujimqin area.Never... During the Late Carboniferous to Early Permian,a rift was formed by post-collisional extension after ocean closure or an island arc-related basin formed by Paleo-Asian Ocean(PAO)subduction in the Xi Ujimqin area.Nevertheless,the closure time of the PAO is still under debate.Thus,to identify the origin of the PAO,the geochemistry and U-Pb age of zircons were analyzed for the extra-large deep marine,polymict clastic boulders and sandstones in the Shoushangou Formation within the basin.The analyses revealed magmatic activity and tectonic evolution.The conglomerates include megaclasts of granite(298.8±9.1 Ma)and granodiorite porphyry(297.1±3.1 Ma),which were deposited by muddy debris flow.Results of this study demonstrated that the boulders of granitoids have the geochemistry of typical I-type granite,characterized by low Zr+Nb+Ce+Y and low Ga/Al values.The granitoid boulders were formed in island arc setting,indicating the presence of arc magmatism in the area that is composed of the Late Carboniferous to Early Permian subduction-related granitoid in southern Xi Ujimqin.Multiple diagrams for determining sedimentary provenance using major and trace elements indicate that Shoushangou sediments originated from continental island arc-related felsic rocks.Detrital zircon U-Pb age cluster of 330–280 Ma was obtained,indicating input from granite,ophiolite,Xilin Gol complex,and Carboniferous sources to the south.The basin was geographically developed behind the arc during the Early Permian period because the outcropped intrusive rocks in the Late Carboniferous to Early Permian form a volcanic arc.The comprehensive analyses of source areas suggest that Shoushangou sediments developed in a backarc basin in response to the northward subduction of the PAO.The backarc basin and intrusive rocks,in addition to previously published Late Carboniferous to Early Permian magmatic rocks of arc unit in Xilin Gol,confirm the presence of an Early Permian trencharc-basin system in the region,represented by the Baolidao arc and Xi Ujimqin backarc basin.This study highlights the importance and potential of combined geochemical and geochronological studies of conglomerates and sandstone for reconstructing the geodynamic setting of a basin. 展开更多
关键词 provenance analysis backarc basin Shoushangou formation Early Permian Central Asian Orogenic Belt
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Analysis of the development and causes of formation of Eucampia zoodiacus red tide in Xiamen Harbor 被引量:2
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作者 Zhang Shuijin ( Third institute of Oceanography, State Oceanic Administration, Xiamen 361005, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1994年第4期589-600,共12页
The red tide event of 11 ̄28, May in 1987 was caused by Eucampia zoodiacus, a coastal eurythermic phytoplanktou. Results from the field monitoring indicated that during the red tide occurrence the optimal temperature ... The red tide event of 11 ̄28, May in 1987 was caused by Eucampia zoodiacus, a coastal eurythermic phytoplanktou. Results from the field monitoring indicated that during the red tide occurrence the optimal temperature and salinity for the multiplication of the red tide organism were 20 ̄25℃ and 26 ̄28. During the red tide event cell densities in two peak values both reached 3 000×103ind. /din3. Organism number in horizonal distribution increased from the harbour mouth to the inner harbour. Average number of the organism at the monitoring stations in the inner harbour was 2 930×103 md. /dm3 which was 3. 7 and 61 times higher than that at the two control monitoring stations. The organism number in vertical distribution apparently showed stepwise, day and night changes. Daily change of the phytoplankton number with spring and ebb tides exhibited a negative relativity.Major reasons for this red tide event included species competition of red tide organisms, sudden increment in water temperature in short time, sharp decrement in salinity by rainfall, water eutrophication, high contents of stimulating materials such as Fe and Mn, poor water exchange condition and stable synoptic condition, etc.High content of dissolved oxygen and high pH value was resulted from the photosythesis of a great quantity of the red tide organisms. 展开更多
关键词 Red tide cause analysis HARBOUR Fujian
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Analysis and Response of Steel Stacking Accidents in Hot Rolling Coilers
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作者 Zhenyi Yu Yuan Long Shuqi Tang 《Frontiers of Metallurgical Industry》 2024年第2期10-14,共5页
Through long-term production and maintenance practice,various types of stacking steel in the 2250mm hot rolling coiler of Ma Steel were tracked and analyzed,and the causes of stacking steel were summarized.Cor-respond... Through long-term production and maintenance practice,various types of stacking steel in the 2250mm hot rolling coiler of Ma Steel were tracked and analyzed,and the causes of stacking steel were summarized.Cor-responding measures were formulated to effectively reduce the probability of stacking steel. 展开更多
关键词 COILER stacking steel cause analysis MEASURE
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Analysis on the Cause of Dense Fog in Jining on November 10,2005 被引量:2
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作者 郭红艳 李永果 马丽 《Meteorological and Environmental Research》 CAS 2010年第5期32-33,47,共3页
Through analyzing the situation of atmospheric circulation and the variation of meteorological element at the time of dense fog happened on November 10,2005 in Jining,the results indicated that there were abundant wat... Through analyzing the situation of atmospheric circulation and the variation of meteorological element at the time of dense fog happened on November 10,2005 in Jining,the results indicated that there were abundant water vapor,weaker pressure field and wind field,weaker cold air in high altitude,stable stratification in underlying bed and ground was located in the bottom of cold high pressure,all those conditions were beneficial to the generation of dense fog in Jining. 展开更多
关键词 Dense fog cause analysis Jining China
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Analysis of Causes for An Unusual Cloudy-rainy Weather for Several Days in Autumn 被引量:1
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作者 张景珍 张莉 +1 位作者 李建明 李静 《Meteorological and Environmental Research》 CAS 2010年第10期20-24,共5页
Cloudy-rainy weather for several days in 2007 was featured with the longest duration and the most serious extent of injury since the time from which there was meteorology observation record in Shandong.The causes of t... Cloudy-rainy weather for several days in 2007 was featured with the longest duration and the most serious extent of injury since the time from which there was meteorology observation record in Shandong.The causes of this process were analyzed in this article in terms of general circulation,character of physical quantity and tropical cyclone.The result showed that the precipitation process was a long wave adjustment process and it took place during the transformation process of general circulation turning from the zonal to the radial.During the cloudy-rainy weather process,the Ural mountain ridge and the Western Pacific subtropical high were more abnormally strong and in the further north than that in any other years.The tropical cyclone in the south of the subtropical cyclone activity was more frequent.There was more shortwave in middle latitudes of Asian.The cold air masses Siberia went down south.The cold air masses joined with the current of air in the Lower Yellow River.This led to the lasting cloudy-rainy weather for several days in Shandong. 展开更多
关键词 Cloudy-rainy weather for several days General circulation Physics characteristics analysis of the causes China
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Statistical and causes analysis of storm surges along Tianjin coast during the past 20 years
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作者 李希彬 孙晓燕 +2 位作者 刘洋 张秋丰 牛福新 《Marine Science Bulletin》 CAS 2014年第1期15-24,共10页
Based on tidal data statistical analysis for 20 years of Tanggu Marine Environmental Monitoring Station from 1991 to 2010, we concluded that an average of nearly 10 days of 100 cm above water increase took place at Ti... Based on tidal data statistical analysis for 20 years of Tanggu Marine Environmental Monitoring Station from 1991 to 2010, we concluded that an average of nearly 10 days of 100 cm above water increase took place at Tianjin coast every year. The maximum high tide and average tide of Tianjin coast occurred in summer and autumn, and the maximum water increase also occurred in summer and autumn. Days with water increase more than 100 cm mostly occurred in spring, autumn and winter. Then we summarized the causes of coastal storm surge disaster in Tianjin based on astronomical tide factors, meteorological factors, sea level rise, land subsidence, and geographic factors, et al. Finally, we proposed storm surge disaster prevention measures. 展开更多
关键词 TIANJIN storm surge water increase statistical analysis cause analysis
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Cause Analysis on the Missing Report of First Thunderstorm Weather in Shenyang City in 2010
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作者 隋东 刘凯 +2 位作者 韦涛 祖歌 曹志贤 《Meteorological and Environmental Research》 CAS 2010年第10期71-74,共4页
The first thunderstorm weather appeared in southern Shenyang on May 2,2010 and did not bring about severe lightning disaster for Shenyang region,but forecast service had poor effect without forecasting thunderstorm we... The first thunderstorm weather appeared in southern Shenyang on May 2,2010 and did not bring about severe lightning disaster for Shenyang region,but forecast service had poor effect without forecasting thunderstorm weather accurately.In our paper,the reasons for missing report of this thunderstorm weather were analyzed,and analysis on thunderstorm potential was carried out by means of mesoscale analysis technique,providing technical index and vantage point for the prediction of thunderstorm potential.The results showed that the reasons for missing report of this weather process were as follows:surface temperature at prophase was constantly lower going against the development of convective weather;the interpreting and analyzing ability of numerical forecast product should be improved;the forecast result of T639 model was better than that of Japanese numerical forecast;the study and application of mesoscale analysis technique should be strengthened,and this service was formally developed after thunderstorm weather on June 1,2010. 展开更多
关键词 THUNDERSTORM Missing report cause analysis:Predicting vantage point China
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Sequence structure, sedimentary evolution and their controlling factors of the Jurassic Lianggaoshan Formation in the East Sichuan Basin, SW China
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作者 CHENG Dawei ZHANG Zhijie +6 位作者 HONG Haitao ZHANG Shaomin QIN Chunyu YUAN Xuanjun ZHANG Bin ZHOU Chuanmin DENG Qingjie 《Petroleum Exploration and Development》 SCIE 2023年第2期293-305,共13页
Based on the data of outcrops, seismic sections, thin sections, heavy mineral assemblages and detrital zircon U-Pb dating, the sedimentary characteristics, lake level fluctuation and provenance characteristics of the ... Based on the data of outcrops, seismic sections, thin sections, heavy mineral assemblages and detrital zircon U-Pb dating, the sedimentary characteristics, lake level fluctuation and provenance characteristics of the Middle Jurassic Lianggaoshan Formation(J_(2)l) in eastern Sichuan Basin, SW China, were investigated to reveal the control of tectonic movements of the surrounding orogenic belts on the sedimentary systems. The J_(2)lmainly developed a delta–lake sedimentary system, which contained a complete third-order sequence that was subdivided into four lake level up-down cycles(fourth-order sequence).The lake basins of cycles Ⅰ and Ⅱ were mainly distributed in eastern Sichuan Basin, while the lake basins of cycles Ⅲ and Ⅳ migrated to central Sichuan Basin, resulting in the significant difference in sedimentary characteristics between the north and the south of eastern Sichuan Basin. The provenance analysis shows that there were three types of provenances for J_(2)l. Specifically, the parent rocks of Type Ⅰ were mainly acidic igneous rocks and from the proximal northern margin of the Yangtze Plate;the parent rocks of Type Ⅱ were intermediate-acid igneous rocks and metamorphic rocks and from the central parts of the southern and northern Qinling orogenic belts;the parent rocks of Type Ⅲ were mainly metamorphic rocks followed by intermediate–acid igneous rocks, and from the North Daba Mountain area. It is recognized from the changes of sedimentary system and provenance characteristics that the sedimentary evolution of J_(2)lin eastern Sichuan Basin was controlled by the tectonic compression of the Qinling orogenic belt. In the early stage, the lake basin was restricted to the east of the study area, and Type Ⅰ provenance was dominant. With the intensifying north-south compression of the Qinling orogenic belt, the lake basin expanded rapidly and migrated northward, and the supply of Type Ⅱ provenance increased. In the middle and late stages, the uplift of the North Daba Mountain led to the lake basin migration and the gradual increase in the supply of Type Ⅲ provenance. 展开更多
关键词 Sichuan Basin JURASSIC Lianggaoshan formation heavy mineral assemblage zircon U-Pb dating lake basin migration provenance analysis basin-mountain evolution
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A Seismic Facies Analysis to Determine the Relative Age and History of the Al Idrissi Mud Volcano from Offshore Larache Located in the NW Moroccan Atlantic Margin
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作者 Asher Hategekamungu Nadia Mhammdi +1 位作者 Mohamed Amine Manar Asmae Bernachid 《Open Journal of Geology》 CAS 2023年第3期203-220,共18页
Formed on top of the Gulf of Cadiz, the Al Idrissi mud volcano is the shallowest and largest mud volcano in the El Arraiche mud volcano field of the northwestern Moroccan margin. The development and morphology of mud ... Formed on top of the Gulf of Cadiz, the Al Idrissi mud volcano is the shallowest and largest mud volcano in the El Arraiche mud volcano field of the northwestern Moroccan margin. The development and morphology of mud volcanoes from the El Arraiche mud volcanoes group have been studied at a large scale. However, the time interval related to their formation period still needs to be better understood. In this regard, we interpreted and analyzed the seismic facies from the 2D reflection data of the GEOMARGEN-1 campaign, which took place in 2011. The aim was to identify the seismic sequences and draw the Al Idrissi mud volcano system to determine the formation period of the Al Idriss mud volcano. And as a result, the Al Idrissi mud volcano system is made of both buried and superficial bicone and was identified along with the Upper Tortonian to Messinian-Upper Pliocene facies. As the initial mud volcano extrusive edifice, the buried bicone was formed in the Late-Messinian to Early-Pliocene period. However, the superficial bicone, as the final extrusive edifice, was included in the Late Pliocene. In this case, the timing interval between the buried and superficial bicone is equivalent to the Late-Messinian to Upper-Pliocene period. Therefore, the latter corresponds to the Al Idrissi mud volcano formation period. 展开更多
关键词 Northwestern Moroccan Margin Al Idrissi Mud Volcano 2D Reflection Data from the GEOMARGEN-1 Campaign Seismic Signatures analysis formation Period
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Characteristics,classification and KNN-based evaluation of paleokarst carbonate reservoirs:A case study of Feixianguan Formation in northeastern Sichuan Basin,China
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作者 Yang Ren Wei Wei +3 位作者 Peng Zhu Xiuming Zhang Keyong Chen Yisheng Liu 《Energy Geoscience》 2023年第3期113-126,共14页
The Feixianguan Formation reservoirs in northeastern Sichuan are mainly a suite of carbonate platform deposits.The reservoir types are diverse with high heterogeneity and complex genetic mechanisms.Pores,vugs and frac... The Feixianguan Formation reservoirs in northeastern Sichuan are mainly a suite of carbonate platform deposits.The reservoir types are diverse with high heterogeneity and complex genetic mechanisms.Pores,vugs and fractures of different genetic mechanisms and scales are often developed in association,and it is difficult to classify reservoir types merely based on static data such as outcrop observation,and cores and logging data.In the study,the reservoirs in the Feixianguan Formation are grouped into five types by combining dynamic and static data,that is,karst breccia-residual vuggy type,solution-enhanced vuggy type,fractured-vuggy type,fractured type and matrix type(non-reservoir).Based on conventional logging data,core data and formation microscanner image(FMI)data of the Qilibei block,northeastern Sichuan Basin,the reservoirs are classified in accordance with fracture-vug matching relationship.Based on the principle of cluster analysis,K-Nearest Neighbor(KNN)classification templates are established,and the applicability of the model is verified by using the reservoir data from wells uninvolved in modeling.Following the analysis of the results of reservoir type discrimination and the production of corresponding reservoir intervals,the contributions of various reservoir types to production are evaluated and the reliability of reservoir type classification is verified.The results show that the solution-enhanced vuggy type is of high-quality sweet spot reservoir in the study area with good physical property and high gas production,followed by the fractured-vuggy type,and the fractured and karst breccia-residual vuggy types are the least promising. 展开更多
关键词 Carbonate reservoir Reservoir type Cluster analysis K-Nearest Neighbor(KNN) Feixianguan formation Sichuan basin
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Analysis of Potential Causes of Safety Failure of New Energy Vehicle Power Batteries
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作者 Shaoqing Xiang 《Journal of Electronic Research and Application》 2023年第3期13-19,共7页
The aim of this paper is to analyze the potential reasons for the safety failure of batteries for new-energy vehicles.Firstly,the importance and popularization of new energy batteries are introduced,and the importance... The aim of this paper is to analyze the potential reasons for the safety failure of batteries for new-energy vehicles.Firstly,the importance and popularization of new energy batteries are introduced,and the importance of safety failure issues is drawn out.Then,the composition and working principle of the battery is explained in detail,which provides the basis for the subsequent analysis.Then,the potential impacts of factors such as overcharge and over-discharge,high and low temperature environments,internal faults,and external shocks and vibrations on the safety of the batteries are analyzed.Finally,some common safety measures and solutions are proposed to improve the safety of new energy batteries,in hopes of improving the safety of batteries for new-energy vehicle. 展开更多
关键词 New-energy vehicle Power battery Safety failure Potential cause analysis and research
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Provenance System Analysis of the Nantun Formation of the Huhehu Sag in Hailar Basin 被引量:2
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作者 LI Junhui MENG Qi'an +4 位作者 LU Shuangfang ZHU Defeng WU Haibo LIU He ZHANG Dazhi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第1期189-198,共10页
Huhehu Sag is a new battlefield for the future oil and gas exploration in the Hailar Basin. At present, exploration of this area stays at a low level and the understanding of the provenance system of the Nantun Format... Huhehu Sag is a new battlefield for the future oil and gas exploration in the Hailar Basin. At present, exploration of this area stays at a low level and the understanding of the provenance system of the Nantun Formation is comparatively weak. So, to carry out the detailed depiction of the provenance system in the study area is significant for the sedimentary system reconstruction, for the prediction of reservoir distribution and favorable areas. Based on comprehensive analysis of paleogeomorphy, light-heavy mineral and seismic reflection features, sandstone thickness and sandstone percentage, this paper analyzes in detail the provenance system of the Nantun Formation in Huhehu Sag from various angles and levels. It shows that provenances of the Huhehu Sag mainly originated from the eastern Xilinbeier Salient and western Bayan Mountain Uplift. The provenances surrounding the lake basin converged to the center of the basin, among which, the steep slope belt and the gentle slope belt are the main provenances, and the southern uplift is a secondary one. The distribution framework of the provenance fundamentally determines the distribution rules of the depositional system and its sand body developing during the Nantun period. 展开更多
关键词 Huhehu Sag Nantun formation provenance analysis sedimentary system
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CHARACTERISTICS AND CAUSE ANALYSIS OF WESTERN PACIFIC SUBTROPICAL HIGH DURING THE HUAIHE RIVER FLOODS IN 2003 被引量:4
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作者 金荣花 矫梅燕 +1 位作者 徐晶 秦华锋 《Journal of Tropical Meteorology》 SCIE 2006年第1期97-98,共2页
1 INTRODUCTION In summer, different assembly of the intensity, location and vertical structure of the subtropical high and the earlier/later time of its seasonal northwards jump bring about different precipitation pat... 1 INTRODUCTION In summer, different assembly of the intensity, location and vertical structure of the subtropical high and the earlier/later time of its seasonal northwards jump bring about different precipitation patterns over China. Therefore, subtropical high activity and its cause during the occurrence of extreme climatic event over China and the cause of China drought/flood are studied to improve weather forecasting. 展开更多
关键词 the Huaihe River floods Western Pacific subtropical high abnormal characteristics cause analysis
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Facies analysis and paleoenvironmental interpretation of Piacenzian carbonate deposits from the Guitar Formation of Car Nicobar Island,India 被引量:2
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作者 Amit K.Ghosh Suman Sarkar 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第6期755-764,共10页
Facies characterization of Piacenzian (late Pliocene) carbonate sediments of the Guitar Formation in Car Nicobar Island,India and the subsequent integration of paleoecological data have been applied to interpret the... Facies characterization of Piacenzian (late Pliocene) carbonate sediments of the Guitar Formation in Car Nicobar Island,India and the subsequent integration of paleoecological data have been applied to interpret the paleoenvironment of the coralline algal-reef deposits.Thin-section analysis reveals that Amphiroa,Corallina and Jania are the dominant geniculate corallines,while Lithothamnion,Mesophyllum,Phymatolithon,Lithophyllum,Spongites and Lithoporella are the major non-geniculate corallines contributing to the sedimentary facies.Numerous small and larger benthic foraminifera also dominate the biogenic assemblages.Corals,barnacle shells,echinoid spines,fragments of bryozoans,mollusks and ostracodes are the subordinate constituents.Grainstones dominate the studied facies while packstones and boundstones (with wackestone elements) are the sub lithofacies showing a fair representation.Six carbonate facies presenting a complete reef complex have been distinguished that were deposited in shallow intertidal,back-reef shelf/lagoon,reef and deeper fore-reef shelf settings.Evidences of coralline algal and benthic foraminiferal assemblages,taphonomic signatures of abrasion and fragmentation,grain size,angularity and encrustation indicate a shallow to relatively deeper bathymetric horizon of approximately 10-60 m that corresponds to a regime of high to moderate hydrodynamic conditions. 展开更多
关键词 Facies analysis Coralline algae Benthic foraminifera Piacenzian Guitar formation Car Nicobar
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A STUDY ON THE EVOLUTION OF GROUNDWATERPOLLUTANTS AND CAUSES OF FORMATION IN MANZHOULI 被引量:1
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作者 YAN Deng-hua, DENG Wei, YANG Jian-qiang, WANG Chun-mei, WU Pei-pei (Changchun Institute of Geography, the Chinese Academy of Sciences, Changchun 130021, P. R. China Jilin University, Changchun 130023, P. R. China Hefei Xingzhi School,Hefei 230011, P. R 《Chinese Geographical Science》 SCIE CSCD 2001年第1期92-96,共5页
Studying the evolution of groundwater pollutants and the causes of formation in Manzhouli is important and necessi- tous as the present water source of the production and living in Manzhouli is just groundwater and th... Studying the evolution of groundwater pollutants and the causes of formation in Manzhouli is important and necessi- tous as the present water source of the production and living in Manzhouli is just groundwater and the water crisis is staring Manzhouli people in the face. The evolution of pollutants in groundwater in Manzhouli was derived based on the continuously monitoring between 1989 and 1999. In total, the quality of groundwater in Manzhouli is good except that the content of F is exceeding the standard. The quality of groundwater varies seasonally. The content of pollutants in high water is higher than in the low water except pH and As. The yearly evolution shows the regime like the damp surge. The evolution of pH is inverse to NO3-N and F after 1999. The courses of formation of the evolution of the content of the pollutants in groundwater in Manzhouli are the supply of runoff, the feature of rock, the time the water being stayed in the layers and the chemical field. Being affected by the supply of ground surface and hydrogeology condition, the contents of pollutant are higher in the May than in September and the yearly evolution is undulance. In total, the pollutants in the deeper layers are less than in the upper layers. Explosion water in the deeper layers, using the techniques of cutting F and minifying the pollutants caused by human being are the sound countermeasures in Manzhouli. 展开更多
关键词 Manzhouli GROUNDWATER POLLUTANTS causes of formation
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Provenance of the Early-Middle Devonian Shugouzi Formation in the Quruqtagh,Northeastern Xinjiang:Constraints from Sandstone Geochemistry and Heavy Mineral Analysis 被引量:1
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作者 ZHANG Yingli WANG Zongqi WANG Tao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第1期193-207,共15页
The Early-Middle Devonian Shugouzi Formation in the Quruqtagh block consists mainly of clastic rocks.However,their provenance has been scarcely studied since it was named.Geochemistry of clastic rocks was commonly use... The Early-Middle Devonian Shugouzi Formation in the Quruqtagh block consists mainly of clastic rocks.However,their provenance has been scarcely studied since it was named.Geochemistry of clastic rocks was commonly used to interpret the provenance.Detrital heavy mineral analyses help frame the U-Pb age from zircon grains,integrated with geochemical data from detrital tourmaline and spinels.These techniques were used to characterize components of the sediment flux and define erosion areas in the Qurugtagh block,further providing evidence about the tectonic evolution of the South Tianshan and Tarim plate.The maximum depositional age constrained by detrital zircon dating was Early-Middle Devonian.Multiple diagrams for sedimentary provenance using major and trace elements indicate that continental island arc-related felsic rocks were the major source rocks for the Shugouzi Formation.Detrital tourmalines are dravite and schorl.The results of detrital tourmaline electron probe microanalysis(EPMA)show that the source rocks are mainly metasedimentary rocks and granitoids.The detrital chromian spinels within the sediments are characterized by high chroumium(Cr^(#))and varying magnesium(Mg^(#)).The discrimination plots reveal that these spinels were sourced from island arc magmatic rocks.The laser ablation inductively-coupled plasma mass spectrometry(LA-ICP-MS)U-Pb chronology of detrital zircons suggests that the sediments were derived mainly from 414-491 Ma and 744-996 Ma magmatic rocks.Paleocurrent restoration,sandstone geochemistry,EPMA,and detrital zircon geochronology indicate that the source rocks were predominantly derived from Late Ordovician and Devonian magmatic rocks and subordinately from recycled Neoproterozoic magmatic rocks.Comprehensive analyses of the source areas suggest that a remnant arc still existed in the Early Devonian and the Shugouzi Formation was deposited in a passive continental margin. 展开更多
关键词 Shugouzi formation provenance analysis tectonic setting passive continental margin Quruqtagh
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Cause Analysis of Crack Formation in HRB400 Screw-Thread Steel 被引量:2
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作者 Pengbiao Wang Qichun Peng +1 位作者 Sanxiang Lei Youhua Wang 《International Journal of Nonferrous Metallurgy》 CAS 2016年第2期16-21,共6页
The analysis of the crack on the HRB400 screw-thread steel surface has been carried out by means of metallographic microscope, scanning electron microscope and EDAX. It is shown that the type of inclusions in the crac... The analysis of the crack on the HRB400 screw-thread steel surface has been carried out by means of metallographic microscope, scanning electron microscope and EDAX. It is shown that the type of inclusions in the crack steel samples is mainly class B oxide, C silicate, and the inclusion size of the majority below 10 μm, and a small number of large inclusions are observed. The content of oxygen in the steel is high, and the carbon segregation is the main reason of the crack formation of HRB400 screw-thread steel. The measures to improve the crack formation of HRB400 screw-thread steel are put forward, which provides a powerful basis for the practical production. 展开更多
关键词 HRB400 Screw-Thread Steel CRACK INCLUSION cause analysis
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Facies Analysis, Depositional Environment and Diagenetic Features of the Qom Formation in the Saran Semnan, Central Iran 被引量:2
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作者 Fereshteh Karami-Movahed Mohsen Aleali Parviz Ghazanfari 《Open Journal of Geology》 2016年第6期349-362,共14页
In this study, to identify and analyze facies of depositional environment and depositional model of Qom Formation, stratigraphic Saran Section (southwest of Semnan) was selected. Qom Formation in Saran section include... In this study, to identify and analyze facies of depositional environment and depositional model of Qom Formation, stratigraphic Saran Section (southwest of Semnan) was selected. Qom Formation in Saran section includes about 380 meters of conglomerate at the base, chalk, limestone, marl, and shale. Petrographic studies with facies analysis have led to the identification of 12 microfacies, these microfacies have been deposited in four facies groups including tidal flat, lagoon, barrier and open marine. Study of horizontal and vertical facies changes and their comparison with recent and ancient environments reveals that Qom Formation in this section relates to shallow marine environment and its facies were deposited in a shelf carbonate platform and are comparable with contemporary shelf platforms such as Florida and old shelf platforms such as Mozduran. The most important diagenetic processes affecting the studied section include micritization, bioturbation, cementation, dissolution, neomorphism, fracturing, mechanical and chemical compaction, hematitization and dolomitization. These processes have formed in marine, meteoric and burial diagenetic environments. 展开更多
关键词 Facies analysis Depositional Environment Qom formation Saran Semnan Centeral Iran
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The Analysis on the Temporal and Spatial Variation of Strong Precipitation Caused Flood and Agricultural Disaster Loss in Huaihe River Basin of Anhui Province during Meiyu Period of 2007 被引量:1
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作者 YU Jia-cheng1,WU Chang-chun1,HUANG Xiao-yan1,HE Yong-qing1,YU Yang2,WANG Sheng2,GUO Xiu-yun2,WANG Hua3 1.Anhui Agricultural University,Hefei 230036,China 2.Anhui Meteorological Bureau,Hefei 230061,China 3.Anhui Civil Affairs Bureau,Hefei 230061,China 《Meteorological and Environmental Research》 CAS 2011年第7期87-90,共4页
[Objective] The research aimed to analyze temporal and spatial variation of strong precipitation caused flood and agricultural disaster loss in Huaihe River basin of Anhui Province during Meiyu period of 2007.[Method]... [Objective] The research aimed to analyze temporal and spatial variation of strong precipitation caused flood and agricultural disaster loss in Huaihe River basin of Anhui Province during Meiyu period of 2007.[Method] On the basis of rainfalls of each station in Huaihe River basin of Anhui,rainfall data during Meiyu period of 2007 and flood disaster data in the same period,the temporal and spatial distribution characteristics of strong precipitation caused flood during Meiyu period of 2007 and its harm on agriculture were analyzed.The variation rule,distribution characteristics of strong precipitation during Meiyu period in Huaihe River basin of Anhui and its relationship with agricultural disaster loss were discussed.[Result] During Meiyu period of 2007 in Huaihe River basin of Anhui,the rainstorm was more,and the rainfall was large.The precipitation variation showed 'three-peak' trend.Rainfall in Huaihe River basin during Meiyu period of 2007 was greatly more than that homochronously in Yangtze River basin.The rain area over 400.0 mm during Meiyu period mainly located in Huaihe River basin,and the rain area over 600.0 mm mainly located from area along Huaihe River to central Huaibei.The rainfall during Meiyu period gradually decreased toward south and north by the north bank of Huaihe River as the symmetry axis.The rainfall in area along Huaihe River showed wavy distribution in east-west direction.The flood disaster loss index and disaster area of crops in Huaihe River basin of Anhui both increased as rainfall in Meiyu period.[Conclusion] The research provided theoretical basis for flood prevention,disaster reduction and agricultural flood-avoiding development in Huaihe River basin. 展开更多
关键词 Huaihe River basin of Anhui Province Meiyu period of 2007 Strong precipitation caused flood Temporal and spatial distribution Agricultural disaster loss Characteristic analysis China
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