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Scientific Drilling-to Construct the Telescopes that Inserting to the Earth Interior 被引量:2
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作者 ZHANG Xiaoxi ZHANG Hui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第S01期87-88,共2页
Mankind live in the earth for countless years, but until now;people do not really understand the connotation of the Earth. We know that the earth composition including the lithosphere, the asthenosphere, mantle and co... Mankind live in the earth for countless years, but until now;people do not really understand the connotation of the Earth. We know that the earth composition including the lithosphere, the asthenosphere, mantle and core. Of course, the lithosphere supports all the life on Earth. For a long time, geoscientists trying to use all kind of methods such as geological, geophysical and geochemical methods to detect and study the earth, but the knowledge about earth are mostly indirect. Through the direct observation to the lithosphere, people can understand and recognize the plate movement of ocean and the mainland, crustal stress, earthquakes, volcanic processes, deep resources, the origins of life, global climate change and biodiversity. They are all the basis of a series of geosciences problems(Su and Yang, 2010). Geological specimens, especially the true samples from deep of the Earth, are the most directly study subjects for geologists. But the only way to access the true samples from deep of the earth is drilling. The most directly relevant evidence always originated from the deep of the earth, such as core, cuttings, fluid samples and other physical samples. Continental scientific drilling has been demonstrated which is an efficient technique for directly obtaining information from the Earth’s surface to the deep crust, and is acknowledged as ―to build a telescope inserting to the interior of the Earth‖, as well as ―a key for opening the door of the Earth‖. Over the last four decades, continental scientific drilling has achieved great success in enhancing our knowledge of the Earth, and in providing information on mineral resources, large engineering projects and global change. SinoProbe-05 is a new scientific drilling venture,which builds on the success of the Chinese Continental Scientific Drilling Project(CCSD), and is similar to the current major scientific drilling project on the Wenchuan earthquake fault. SinoProbe-05 will focus on 6 critical tectonic and mineral resource regions, including the Jinchuan Cu-Ni sulphide deposits in Gansu, the Luobusa chromite deposits in Tibet, the Tengchong volcano-thermal tectonic zone in Yunnan, the Yudu-Ganxian polymetallic deposits in South China, the Tongling polymetallic deposit and the Luzong volcanic basin and mineral deposit district in Anhui. As of the end of 2013, all of these pilot holes have been completed, all of them have achieved the desired scientific objectives. The construction of another ICDP project, Songke No.2 well, has come to an end. Current well depth is 5929 m. Drilling throughout the Cretaceous strata is just around the corner(The design well depth is 6400 m.). This will be the first complete Cretaceous stratigraphic profile in the world. The deep exploration project which will be stared soon will build a large number of different depths of scientific drilling holes. The deepest hole depth will reach to 13000 m. We believe that the construction of these scientific coring drilling holes will provide geologists with a lot of real core samples. These cores can meet the needs for different geoscience research areas. No doubt, the research results based on these cores will promote China’s geological science research to a new height, of course;will also contribute to the progress of the world’s earth science. This is also a good opportunity to promote China’s drilling technology. So, we know that no advanced drilling technology, no enough high quality samples from the deep of the Earth, the in-depth studies for geosciences will be restricted of course(Zhang et al., 2013). 展开更多
关键词 scientific drilling drilling technology true samples Telescopes inserting to the earth
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The 600 keV electron injections in the Earth's outer radiation belt:A statistical study 被引量:2
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作者 ChaoLing Tang Xu Wang +2 位作者 BinBin Ni ZhengPeng Su JiChun Zhang 《Earth and Planetary Physics》 EI CSCD 2022年第2期149-160,共12页
Relativistic electron injections are one of the mechanisms of relativistic(≥0.5 MeV) electron enhancements in the Earth’s outer radiation belt. In this study, we present a statistical observation of 600 keV electron... Relativistic electron injections are one of the mechanisms of relativistic(≥0.5 MeV) electron enhancements in the Earth’s outer radiation belt. In this study, we present a statistical observation of 600 keV electron injections in the outer radiation belt by using data from the Van Allen Probes. On the basis of the characteristics of different injections, 600 keV electron injections in the outer radiation belt were divided into pulsed electron injections and nonpulsed electron injections. The 600 keV electron injections were observed at 4.5 < L <6.4 under the geomagnetic conditions of 450 nT < AE < 1,450 nT. An L of ~4.5 is an inward limit for 600 keV electron injections. Before the electron injections, a flux negative L shell gradient for ≤0.6 MeV electrons or low electron fluxes in the injected region were observed. For600 keV electron injections at different L shells, the source populations from the Earth’s plasma sheet were different. For 600 keV electron injections at higher L shells, the source populations were higher energy electrons(~200 keV at X ~–9 R_(E)), whereas the source populations for 600 keV electron injections at lower L shells were lower energy electrons(~80 keV at X ~–9 R_(E)). These results are important to further our understanding of electron injections and rapid enhancements of 600 keV electrons in the Earth’s outer radiation belt. 展开更多
关键词 electron injections relativistic electrons the earth’s outer radiation belt plasma sheet Van Allen Probes
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Origin of the Earth:A proposal of new model called ABEL 被引量:10
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作者 Shigenori Maruyama Toshikazu Ebisuzaki 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第2期253-274,共22页
The Earth was born as a dry planet without atmosphere and ocean components at 4.56 Ga,with subsequent secondary accretion of bio-elements,such as carbon(C),hydrogen(H),oxygen(O),and nitrogen(N) which peaked at... The Earth was born as a dry planet without atmosphere and ocean components at 4.56 Ga,with subsequent secondary accretion of bio-elements,such as carbon(C),hydrogen(H),oxygen(O),and nitrogen(N) which peaked at 4.37-4.20 Ga.This two-step formation model of the Earth we refer to as the advent of bio-elements model(ABEL Model) and the event of the advent of bio-elements(water component) as ABEL Bombardment.It is clear that the solid Earth originated from enstatite chondrite-like dry material based on the similarity in oxygen isotopic composition and among other isotopes.On the other hand,Earth's water derives primarily from carbonaceous chondrite material based on the hydrogen isotopic ratio.We present our ABEL model to explain this enigma between solid Earth and water,as well as secondary accretion of oxidizing bio-elements,which became a precursor to initiate metabolism to emerge life on a highly reductive planet.If ABEL Bombardment had not occurred,life never would have emerged on the Earth.Therefore,ABEL Bombardment is one of the most important events for this planet to evolve into a habitable planet.The chronology of ABEL Bombardment is informed through previous researches of the late heavy bombardment and the late veneer model.ABEL Bombardment is considered to have occurred during 4.37-4.20 Ga,which is the concept to redefine the standard late heavy bombardment and the late veneer models.Also,ABEL Bombardment is the trigger of the transition from stagnant lid tectonics to plate tectonics on this planet because of the injection of volatiles into the initial dry Earth. 展开更多
关键词 Origin of earth and life Advent of bin-elements (ABEL)Origin of water on the earth ABEL Bombardment Habitable Trinity planet Initiation of plate tectonics
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Spatial-temporal variations in near-surface soil freeze-thaw cycles in the source region of the Yellow River during the period 2002–2011 based on the Advanced Microwave Scanning Radiometer for the Earth Observing System(AMSR-E) data 被引量:5
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作者 WANG Rui ZHU Qingke +1 位作者 MA Hao AI Ning 《Journal of Arid Land》 SCIE CSCD 2017年第6期850-864,共15页
Detecting near-surface soil freeze-thaw cycles in high-altitude cold regions is important for understanding the Earth's surface system, but such studies are rare. In this study, we detected the spatial-temporal varia... Detecting near-surface soil freeze-thaw cycles in high-altitude cold regions is important for understanding the Earth's surface system, but such studies are rare. In this study, we detected the spatial-temporal variations in near-surface soil freeze-thaw cycles in the source region of the Yellow River(SRYR) during the period 2002–2011 based on data from the Advanced Microwave Scanning Radiometer for the Earth Observing System(AMSR-E). Moreover, the trends of onset dates and durations of the soil freeze-thaw cycles under different stages were also analyzed. Results showed that the thresholds of daytime and nighttime brightness temperatures of the freeze-thaw algorithm for the SRYR were 257.59 and 261.28 K, respectively. At the spatial scale, the daily frozen surface(DFS) area and the daily surface freeze-thaw cycle surface(DFTS) area decreased by 0.08% and 0.25%, respectively, and the daily thawed surface(DTS) area increased by 0.36%. At the temporal scale, the dates of the onset of thawing and complete thawing advanced by 3.10(±1.4) and 2.46(±1.4) days, respectively; and the dates of the onset of freezing and complete freezing were delayed by 0.9(±1.4) and 1.6(±1.1) days, respectively. The duration of thawing increased by 0.72(±0.21) day/a and the duration of freezing decreased by 0.52(±0.26) day/a. In conclusion, increases in the annual minimum temperature and winter air temperature are the main factors for the advanced thawing and delayed freezing and for the increase in the duration of thawing and the decrease in the duration of freezing in the SRYR. 展开更多
关键词 Advanced Microwave Scanning Radiometer for the earth Observing System air temperature near-surface soil freeze-thaw cycles source region of the Yellow River
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Mafic Dyke Swarms: Their Temporality and Bearing on the Secular Evolution of the Earth
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作者 Michael A.HAMILTON 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期12-,共1页
Pioneering U-Pb isotopic studies by a small group of workers in the mid-late 1980s demonstrated the feasibility of using rare accessory mineral chronometers in mafic(gabbroic)intrusive rocks.These examples showed that... Pioneering U-Pb isotopic studies by a small group of workers in the mid-late 1980s demonstrated the feasibility of using rare accessory mineral chronometers in mafic(gabbroic)intrusive rocks.These examples showed that mafic layered intrusions and diabase/dolerite dyke swarms alike crystallized high-temperature 展开更多
关键词 Mafic Dyke Swarms their Temporality and Bearing on the Secular Evolution of the earth
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The principal moments of inertia calculated with the hydrostatic equilibrium figure of the Earth
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作者 Chengjun Liu Chengli Huang Mian Zhang 《Geodesy and Geodynamics》 2017年第3期201-205,共5页
As an indication of the Earth's mass distribution, the principal moments of inertia (PMOI, i.e., A, B, C) of the Earth are the basic parameters in studies of the global dynamics of the earth, like earth nutation, a... As an indication of the Earth's mass distribution, the principal moments of inertia (PMOI, i.e., A, B, C) of the Earth are the basic parameters in studies of the global dynamics of the earth, like earth nutation, and the geophysics. From the aspect of observation, the PMOI can be calculated from the spherical coefficients of observed gravity field. In this paper, the PMOI are calculated directly according to its definition with the figures of the Earth's interior derived by a generalized theory of the hydrostatic equilibrium figure of the Earth. We obtain that the angle between the principal axis of the maximum moment of PMOI and the rotational axis is 0.184~, which means that the other two principal axes are very closely in the equatorial plane. Meanwhile, B-A is 1.60 x 10-5 MR2, and the global dynamical flattening (H) is calculated to be 3.29587 ~ 10-3, which is 0.67% different from the latest observation derived value Hobs(3.273795 × 10 ^-3) (Petit and Luzum, 2010), and this is a significant improvement from the 1.1% difference between the value of H derived from traditional theories of the figure of the Earth and the value of Hobs. It shows that we can calculate the PMOI and H with an appropriate accuracy by a gener- alized theory of the hydrostatic equilibrium figure of the Earth. 展开更多
关键词 Principal moments of inertia (PMOI) Hydrostatic equilibrium figure the earth's dynamical flattening
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Sources of IR Radiation in the Earth’s Atmosphere in Connection with the PeTa Effect
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作者 Vitali A. Tatartchenko 《Optics and Photonics Journal》 2021年第6期152-196,共45页
The PeTa (Perelman-Tatartchenko) effect is the radiation of the energy of a first-order phase transition during the transition from a less condensed phase to a more condensed one. The effect was independently discover... The PeTa (Perelman-Tatartchenko) effect is the radiation of the energy of a first-order phase transition during the transition from a less condensed phase to a more condensed one. The effect was independently discovered by M. Perelman and the author of this paper. Six papers on the PeTa effect have been published in this journal over the past nine years. They are devoted to the development of PeTa models to explain the following phenomena: IR radiation from cold surfaces, cavitation luminescence/sonoluminescence (CL/SL), laser-induced bubble luminescence (LIBL), and vapor bubble luminescence (VBL) in underwater geysers. This paper describes the sources of PeTa radiation in the Earth’s atmosphere. These sources of infrared radiation have been investigated by numerous research groups, but their interpretation either does not exist at all, or it is erroneous. The following phenomena are specifically considered: PeTa radiation during the formation of clouds and fog;a pulse laser based on the PeTa radiation;condensation explosions as sources of PaTa radiation;measurement of the concentration of water vapor in the atmosphere using PeTa radiation;atmospheric scintillation of infrared radiation in the atmosphere due to the PeTa effect;PeTa radiation as a source of comfort for the igloo;the influence of PeTa radiation on living organisms;PeTa radiation due to characteristics of tropical storms;PeTa radiation as a possible precursor to earthquakes. The problem of global warming, which worries everyone, as it turns out, is also associated with the PeTa effect. 展开更多
关键词 PeTa (Perelman-Tatartchenko) Effect Sources of PeTa Radiation in the earth’s Atmosphere Pulse IR Laser Condensation Explosions Atmospheric IR Scintillations Tropical Storms earthQUAKES Global Warming
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Unit 9 Saving the earth课本要点精练
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作者 吕飞 《中学生英语(高中版)》 2008年第32期10-11,48,共3页
一、单词拼写根据句意和首写字母或汉语提示,写出句中所缺单词的完全形式。1.We should build a better society in
关键词 单项填空 完成句子 Unit 9 Saving the earth
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Unit 9 Saving the earth学习指导
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作者 陈春艳 《中学生英语(高中版)》 2005年第22期8-9,共2页
关键词 学习指导 不及物动词 Unit 9 Saving the earth
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The Impact of the Earth’s Movement through the Space on Measuring the Velocity of Light(Part Two)
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作者 Milos Cojanovic 《Journal of Applied Mathematics and Physics》 2017年第3期741-757,共17页
In this paper is presented an experiment that has a goal to measure the speed of light in one direction, using one clock and one mirror. To achieve this, we have to make the measurements during the period of one year ... In this paper is presented an experiment that has a goal to measure the speed of light in one direction, using one clock and one mirror. To achieve this, we have to make the measurements during the period of one year (nine months at least), taking into account earth’s movement through the space, earth’s rotation around its axis and the fact that earth spin axis is tilted with respect to the plane of its orbit of the sun. 展开更多
关键词 Speed of Light One Way Speed of Light Absolute Velocity of the earth
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The Salt of the Earth
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作者 Hou Weili 《ChinAfrica》 2011年第2期22-23,共2页
Dedicated rural Communist Party members are the catalyst for rural reform CHANG Desheng made a promise to serve the people 45 years ago. When he joined the Communist Party of China(CPC) in 1966, Chang,now 67,and secre... Dedicated rural Communist Party members are the catalyst for rural reform CHANG Desheng made a promise to serve the people 45 years ago. When he joined the Communist Party of China(CPC) in 1966, Chang,now 67,and secretary of Jiangxiang Village Party Branch Committee, in east China’s Jiangsu Province,lived in a poor village with few facilities.He has since helped transfer Jiangxiang into a successful model for other communities to follow. "The income of my family this year 展开更多
关键词 CPC the Salt of the earth
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Reading skills practice:About the Earth
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作者 英国大使馆文化教育处 《疯狂英语(初中天地)》 2019年第1期53-54,共2页
关键词 In Reading skills practice:About the earth
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Possible Evolutionary Models in the Initially Hydride Earth Theory
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作者 Kudryavtsev Pavel 《International Journal of Geosciences》 CAS 2023年第5期377-426,共50页
A modern view of the properties of chemical elements has confirmed the theory of the hot origin of the Earth. The next step in developing this theory was the hypothesis of the initial hydride Earth. In this work, we a... A modern view of the properties of chemical elements has confirmed the theory of the hot origin of the Earth. The next step in developing this theory was the hypothesis of the initial hydride Earth. In this work, we attempted to find additional evidence for this hypothesis and show additional effects that flow from it. The effect of the physical properties of atoms and ions on their behavior during the formation of the Earth was studied. The maximum contribution to the distribution of elements was made by those elements whose content in the original protoplanets of the disk was the maximum. Correlation dependence is obtained, which allows one to calculate the distribution of elements in the protoplanetary disk. It was shown that hydrogen was the main element in the proto substance located in the zone of the Earth’s formation. In this case, various chemical compounds formed, most represented by hydrogen compounds—hydrides. Since the pressure inside the Earth is 375 GPa, this factor forces the chemical compounds to adopt stoichiometry and structure that would not be available in atmospheric conditions. It is shown that many chemical elements at high pressure in a hydrogen medium form simple hydrides and super hydrides—polyhydrides with high hydrogen content. Pressure leads to a higher density of matter inside the planet. Given the possibility of forming polyhydrides, there is the possibility of binding the initially available hydrogen in an amount that can reach 49.3 mole%. Young Earth could contain about 10.7 mass% of hydrogen in hydrides, polyhydrides, and adsorbed form is almost twice higher than previous estimates. This fact additionally confirms the theory of the original hydride Earth. In hydrides, the occurrence of the phenomenon of superconductivity was discovered. Polyhydrides were shown as potential superconductors with a high critical temperature above 200 K. We, based on these data, hypothesized the presence of superconducting properties in the Earth’s core, which explains the presence of a magnetic field in the Earth, as well as the unevenness and instability of this field and the possibility of migration of the Earth’s poles. The fact that the Earth has a hydroid core causes its change in time due to the instability of hydrides. Arranged several possible models of the destruction of the Earth’s core. The calculations showed that both models give close results. These results give predictions that can be measured. The proposed models also made it possible to estimate the initial size of the Earth. Possible ways of further testing the hypothesis of the initial hydride Earth is shown. 展开更多
关键词 theory of the Hot Origin of the earth Magnetic Separation of Elements Atom Ionization Energy Hydrides Polyhydrides earth Expansion Superconductivity of the earth’s Core
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Study on the interannual variability of the Kerama Gap transport and its relation to the Kuroshio/Ryukyu Current system
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作者 Han Zhou Kai Yu +3 位作者 Jianhuang Qin Xuhua Cheng Meixiang Chen Changming Dong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期1-14,共14页
An analysis of a 68-year monthly hindcast output from an eddy-resolving ocean general circulation model reveals the relationship between the interannual variability of the Kerama Gap transport(KGT)and the Kuroshio/Ryu... An analysis of a 68-year monthly hindcast output from an eddy-resolving ocean general circulation model reveals the relationship between the interannual variability of the Kerama Gap transport(KGT)and the Kuroshio/Ryukyu Current system.The study found a significant difference in the interannual variability of the upstream and downstream transports of the East China Sea-(ECS-)Kuroshio and the Ryukyu Current.The interannual variability of the KGT was found to be of paramount importance in causing the differences between the upstream and downstream ECS-Kuroshio.Additionally,it contributed approximately 37%to the variability of the Ryukyu Current.The interannual variability of the KGT was well described by a two-layer rotating hydraulic theory.It was dominated by its subsurface-intensified flow core,and the upper layer transport made a weaker negative contribution to the total KGT.The subsurface flow core was found to be mainly driven by the subsurface pressure head across the Kerama Gap,and the pressure head was further dominated by the subsurface density anomalies on the Pacific side.These density anomalies could be traced back to the eastern open ocean,and their propagation speed was estimated to be about 7.4 km/d,which is consistent with the speed of the local first-order baroclinic Rossby wave.When the negative(positive)density anomaly signal reached the southern region of the Kerama Gap,it triggered the increase(decrease)of the KGT towards the Pacific side and the formation of an anticyclonic(cyclonic)vortex by baroclinic adjustment.Meanwhile,there is an increase(decrease)in the upstream transport of the entire Kuroshio/Ryukyu Current system and an offshore flow that decreases(increases)the downstream Ryukyu Current. 展开更多
关键词 Kerama Gap KUROSHIO Ryukyu Current OGCM for the earth Simulator(OFES) hydraulic theory
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We Live on a Small Space Comet: The Third Extraordinary Motion of Earth towards the North Pole and Its Various Effects
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作者 Walid Nabil 《Advances in Aerospace Science and Technology》 2023年第3期21-33,共13页
The idea of research started with a crazy imaginary theory in the field of astrogeography, saying: We often taught ourselves and then convinced the students that the planet Earth moves despite not feeling the vibratio... The idea of research started with a crazy imaginary theory in the field of astrogeography, saying: We often taught ourselves and then convinced the students that the planet Earth moves despite not feeling the vibrations of traffic, and we listed successive scientific confirmations to indicate the rotation of the planet in a regular movement around its axis once every 24 hours, and it is running in another second movement around the sun once every 365¼ days, so are they only two movements, no more?! Is it possible for him to run at a regular speed in an additional direction? 展开更多
关键词 the Third Additional Regular Movement of the Planet earth towards the North Pole the Movement of the Planet earth in Space the Spiral Path of the earth the Speed of the Planet 1.3 Kilometers per Second the Planet earth A Small Space Comet
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Detection of Earth's free oscillation excited by the Japan Mw9.0 Earthquake using different tiltmeter and strainmeter 被引量:1
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作者 Yan Zhang Fangjie Meng 《Geodesy and Geodynamics》 2018年第5期398-403,共6页
The observatory network of the Crustal Deformation China Seismological Bureau was equipped with vertical pendulum tiltmeter,borehole tiltmeter,tunnel extension meters,multi-component borehole strainmeter,body strainme... The observatory network of the Crustal Deformation China Seismological Bureau was equipped with vertical pendulum tiltmeter,borehole tiltmeter,tunnel extension meters,multi-component borehole strainmeter,body strainmeter and other tilt and strain observation instruments.All of these instruments have recorded the Earth’s free oscillation excited by the Japan Mw9.0 Earthquake.By analyzing those observations,all of the spheroidal oscillation modes(0S3-0S30)and toroidal oscillation modes(0T3-0T20)excited by the Japan Mw9.0 Earthquake were detected in this paper.In addition,comparing the different observation results which obtained by those instruments,we revealed their capacity to observe different kinds of oscillation and different frequency band modes,and analyzed report the reason.We found that the body strainmeter and the vertical pendulum tiltmeter have better observing results for spheroidal oscillation.Because of high noise in low frequency band,the borehole tiltmeter cannot observe the low-order spheroidal oscillation.In terms of observing the toroidal oscillation,the multi-component borehole strainmeter got a best result.The vertical pendulum tiltmeter observes a few toroidal oscillation modes,and the tunnel extension meters can only observe some low-order modes. 展开更多
关键词 TILTMETER Strainmeter Free oscillation of the earth Tohoku earthquake
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思维碰撞,打造高效语法课堂——以《Protect the earth》Grammar time板块教学为例
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作者 徐建 《新教育(海南)》 2016年第24期60-61,共2页
《英语课程标准》指出:英语课程承担着培养学生基本英语素养和发展学生英语思维能力的任务。然而,在小学英语语法课上,很多老师习惯于语法规则的传授,采用“讲解+练习”的模式,忽略了学生思维能力的发展和语用能力的培养。本文以译林英... 《英语课程标准》指出:英语课程承担着培养学生基本英语素养和发展学生英语思维能力的任务。然而,在小学英语语法课上,很多老师习惯于语法规则的传授,采用“讲解+练习”的模式,忽略了学生思维能力的发展和语用能力的培养。本文以译林英语六(上)Unit 7《Protect the earth》Grammar time板块教学为例,探讨在小学英语语法课中训练和培养学生的思维能力。一、精心设计话题。 展开更多
关键词 板块教学 思维能力 思维碰撞 Protect the earth Grammar time 语法课堂 语法项目
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The core-merging giant impact in Earth's accretion history and its implications
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作者 You Zhou Yun Liu +1 位作者 Christian Reinhardt Hongping Deng 《Acta Geochimica》 EI CAS CSCD 2022年第4期553-567,共15页
The Earth’s accretion process is accompanied by a large number of collisions.It is widely accepted that collisions dominate the Earth’s late accretion stage.Among all these collisions,there is a special type of coll... The Earth’s accretion process is accompanied by a large number of collisions.It is widely accepted that collisions dominate the Earth’s late accretion stage.Among all these collisions,there is a special type of collision called Core-merging giant impact(CMGI),in which much or most the impactor’s core merges directly with the protoEarth’s core.This core-merging scenario plays an important role in the Earth’s accretion process and deeply affects the formation of the Earth’s core and mantle.However,because CMGI is a small probability event,it has not been fully studied.Here we use the SPH method to comprehensively study all possible CMGIs in the Earth’s accretion history.We find that CMGI only occurs in the initial conditions with small impact angle,small impact velocity and big impactor.We further discuss the implications of CMGI.We are confident that CMGI inevitably causes the chemical disequilibrium of the Earth’s core and mantle.The CMGI process also brings many light elements into the Earth’s core.In particular,if the Moon-forming giant impact is a CMGI,then CMGI can also explain the abnormal content of HSEs in the Earth’s current mantle. 展开更多
关键词 Giant impact Core-merging process Disequilibrium of the earth’s core and mantle
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Comment on “Evolution model of the earth's limited expanding” from comparative planetology
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作者 SHI YaolinGraduate School, University of Science and Technology of China, Chinese Academy of Sciences, Beijing 100039, China 《Chinese Science Bulletin》 SCIE EI CAS 2001年第17期1495-1496,共2页
In the article 'Evolution Model of the Earth’s Limited Expanding' published in Volume 45 Number (4) of Chinese Science Bulletin[1], the author suggests that the earth expands according to a law R(t) = R0+A(1 ... In the article 'Evolution Model of the Earth’s Limited Expanding' published in Volume 45 Number (4) of Chinese Science Bulletin[1], the author suggests that the earth expands according to a law R(t) = R0+A(1 -exp(β(t-ts))) (remark: this formula was mistakenly printed as R(t) = R0 + Aexp(β(t-ts)) in the and formula (12) of the text of ref. [1]). According to ref. [1], the earth was formed 4.6 billion years ago. After 0.3 billion years from its birth (ts), it started expansion from an initial radius R0 of 4651 km, and may reach a final maximum radius of R0+A = 6511 km. In the 4.6 billion years history, the radius of the earch has increased by 1720 km, or the density decreased from 14200 km/m3 (2.57 times the present density) to 5520 kg/m3 within the latest 4.3 billion years. 展开更多
关键词 from comparative planetology Evolution model of the earth’s limited expanding
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A Japanese Record of an Annular Solar Eclipse and Variation of the Earth's Rotation
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作者 韩延本 《Chinese Science Bulletin》 SCIE EI CAS 1994年第23期2023-2024,共2页
Although the Japanese records of central or near central solar eclipses (i.e. the total, annular and total-annular eclipses) are not very old, so long as their documents definitely recording the observational place, d... Although the Japanese records of central or near central solar eclipses (i.e. the total, annular and total-annular eclipses) are not very old, so long as their documents definitely recording the observational place, date and phenomenon of the eclipse or the parameters can be defined through some textual researches even if 展开更多
关键词 A Japanese Record of an Annular Solar Eclipse and Variation of the earth’s Rotation very
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