检索结果-南通市图书馆

Distribution of Radioactive Elements and Their Relation to the radiogenic Heat Production at Jabal Kharazah Area, North Eastern Desert, Egypt

引用

Journal of Geoscience and Environment Protection 2020年第4期8卷 155-168页

作者： Mohamed A. Shaheen Exploration Sector Nuclear Materials Authority Maadi Cairo Egypt

A map of radiogenic heat production RHP was constructed from airborne spectral gamma-ray data of Jabal Kharazah area, North Eastern Desert, Egypt. The study area possesses a range of RHP varying from 0.2 to 5.7 μW/m-3 with an average value 1.38 μW/m-3, while the standard deviation value is 0.7 μW/m-3. The maximum values are associated with the acidic rocks in the northeast, southeast and a small portion in the northwest zones. About 68% of the readings are higher than the average RHP value in the area, thus Jabal Kharazah area can be considered as heat production area due to the relatively high radioactive mineral concentrations. There are excellent relationships between the derived RHP and the three radioactive elements, Uranium (eU), Thorium (eTh) and Potassium (K).

关键词： radiogenic Heat Production RHP Jabal Kharazah Area Airborne Spectral Gamma-Ray

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The Effect of radiogenic Heating on the Amino Acid Content of an Early Cometary Body

引用

International Journal of Astronomy and Astrophysics 2013年第3期3卷 278-284页

作者： Carlo Canepa Dipartimento di Chimica Università di Torino Torino Italy

This study compares the rates for the formation and destruction of amino acids in the liquid cometary core subjected to radiogenic heating by the β+ decay of the cosmogenic nuclide 26Al. The evolution of the temperature and mass of the comet were computed along with the dynamics of relatively complex organic species such as amino acids. Given the experimentally determined rate coefficient for the radiolysis of amino acids in water solution, the destruction of amino acids is virtually completed after an absorbed radiation dose of ~1 kGy. The calculations suggest that the liquid water core in comets with an initial radionuclide abundance that is sufficient to crystallize and melt the original amorphous ice is subjected to a dose of 100 - 1500 kGy. Any amino acid concentration formed in water either by radiolysis of simpler compounds or by thermal processes such as the synthesis of Strecker could not survive the irradiation delivered by the decay of 26Al.

关键词： Amino Acids radiogenic Heating Comet Prebiotic Chemistry

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petrogenesis of Quebrada de la Mina and Altar North porphyries (Cordillera of San Juan, Argentina): Crustal assimilation and metallogenic implications

引用

Geoscience Frontiers 2017年第5期8卷 1135-1159页

作者： Laura Maydagán Marta Franchini Massimo Chiaradia Verónica Bouhier Noelia Di Giuseppe Roger Rey Luis Dimieri Centro Patagónico de Estudios Metalogenéticos-CONICET Argentina INGEOSUR-CONICET Departamento de Geología Universidad Nacional del Sur San Juan 670 8000 Bahía Blanca Argentina Instituto de Investigación en Paleobiología y Geología Universidad Nacional de Río Negro Av. Roca 1242 8332 Roca Argentina Departamento de Geología y Petróleo Facultad de Ingeniería Universidad Nacional del Comahue Buenos Aires 1400 8300 Neuquén Argentina Section of Earth and Environmental Sciences University of Geneva Switzerland Minera Peregrine Argentina S.A Santa Fe (Oeste) 117 Piso 4B Edificio Derby Ciudad San Juan Argentina

We investigate the geology of Altar North(Cu-Au) and Quebrada de la Mina(Au) porphyry deposits located in San Juan Province(Argentina), close to the large Altar porphyry copper deposit(995 Mt,0.35% Cu, 0.083 g/t Au), to present constraints on the magmatic processes that occurred in the parental magma chambers of these magmatic-hydrothermal systems. Altar North deposit comprises a plagioclase-amphibole-phyric dacite intrusion(Altar North barren porphyry) and a plagioclaseamphibole-biotite-phyric dacite stock(Altar North mineralized porphyry, 11.98 ± 0.19 Ma). In Quebrada de la Mina, a plagioclase-amphibole-biotite-quartz-phyric dacite stock(QDM porphyry,11.91±0.33 Ma) crops out. High Sr/Y ratios(92-142) and amphibole compositions of Altar North barren and QDM porphyries reflect high magmatic oxidation states(fO_2= NNO+1.1 to+1.6) and high fH_2O conditions in their magmas. Zones and rims enriched in anorthite(An_(37-48))), SrO(0.22-0.33 wt.%)and FeO(0.21-0.37 wt.%) in plagioclase phenocrysts are evidences of magmatic recharge processes in the magma chambers. Altar North and Quebrada de la Mina intrusions have relatively homogeneous isotopic compositions(^(87)Sr/^(86)Sr_(t)= 0.70450-0.70466, ε_(ND)(t) = +0.2 to +1.2) consistent with mixed mantle and crust contributions in their magmas. Higher Pb isotopes ratios(^(207)Pb/^(204)Pb=15.6276-15.6294) of these intrusions compared to other porphyries of the district, reflect an increase in the assimilation of high radiogenic Pb components in the magmas. Ages of zircon xenocrysts(297,210,204,69 Ma) revealed that the magmas have experienced assimilation of Miocene, Cretaceous, Triassic and Carboniferous crustal *** that precipitated sulfides in the Altar deposit may have remobilized Pb from the host rocks, as indicated by the ore minerals being more radiogenic(207Pb/204 Pb = 15.6243-15.6269) than their host intrusions. Au/Cu ratio in Altar porphyries(average Au/Cu ratio of 0.14 ×10^(-4)by weight in Altar Central)is hig

关键词： Porphyry High sulfidation epithermal Magmatic recharge radiogenic isotopes Crustal assimilation Argentinian Andes

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

UPDATED REPORT ON HEAT FLOW DATA IN XIZANG

引用

Chinese Science Bulletin 1989年第20期34卷 1728-1732页

作者：沈显杰张文仁杨淑贞沈继英张容燕杨中科夏斯高 Institute of Geology Academia Sinica Beijing

The first set of terrestrial heat flow data on the Qing-Zang (Qinghai-Xizang) Plateau was obtained in the Yamzho and Puma lakes in 1982 (the average values are 146 mW/m^2 and 91 mW/m^2 respectively). On this basis a multi-layered abnormal crust and upper mantle thermal structure model was successively summarized. Furthermore, the mechanism of the thermo-tectonic evolution of the uplift of the Qing-Zang Plateau

关键词： borehole heat flow radiogenic heat production thermo-tectonic evolution

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Some progress on understanding the Phanerozoic granitoids in China

引用

China Geology 2018年第1期1卷 84-108页

作者： Tao Wang Ying Tong Xiao-xia Wang Jian-ren Mao Hong-rui Zhang He Huang Shan Li Lei Guo Jian-jun Zhang Key Laboratory of Deep-Earth Dynamics Ministry of Natural ResourcesBeijing 100037China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Key Laboratory of Metallogeny and Mineral Assessment of Ministry of Natural Resources Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Nanjing center China Geological SurveyNanjing 210016China

There are large volumes of the Phanerozoic granitoid rocks in China and neighboring *** recent years,numerous new and precise U-Pb zircon ages have been published for these granitoids,and define many important magmatic events,such as ca.500 Ma granitoid events in the West Junggar,Altai orogens in the NW China,and Qinling orogen in the central *** ages accurately constrain the time of important early Paleozoic,late Paleozoic,early Mesozoic and late Mesozoic magmatic events of the northern,central,western,southern and eastern orogenic Mountains in *** occur various types of granitoids in China,such as talc-alkaline granite,alkali granite,highly-fractionated granite,leucogranite, adakite,and rapakivi *** granites are not only typical Proterozoic as in the North China Craton,but were also emplaced during Paleozoic and Mesozoic in the Kunlun-Qinling orogen,a part of the China Central Orogenic Belt (CCOB).Nd-Hf isotopic tracing and mapping show that granitoids inthe southern Central Asian Orogenic Belt (CAOB)in China (or the Northern China Orogenic Belt)are characterized predominantly by juvenile *** juvenile crust in this orogenic domain accounts for over 50% by area,distinguishing it from other orogenic belts in the world,and those in central (e.g.,Qinling),southwestem and eastern *** on a large amount of new age data,a preliminary granitoid and granitoid-tectonic maps of China have been preliminarily compiled,and an evolutionary framework of Phanerozoic granitoids in China and neighboring areas has been established from the view of assembly and breakup of continental *** ideas on granitoid tectonics has also been proposed and discussed.

关键词： Granitoids Zircon age Spatial-temporal distribution radiogenic isotopes Orogen

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：