陨石的

Ureilite is a particular kind of achondrite. It has not only highly fractionated igneous characteristics, but also primitive chondritic properties.

橄辉无球粒陨石是一类特殊的无球粒陨石，既具有高度分异的火成特征，又具有原始球粒陨石的特征。

Rafruti ataxite has the youngest exposure age,(6.9± 1.5) Ma, of all ataxites, whereas Ningbo with that of (107± 15) Ma falls within the range of the other ochedrites.

其中Rafruti无结构铁陨石为(6.9±1.5)Ma，在所有无结构铁陨石中是最低的；宁波铁陨石为(107±15)Ma，落在八面体铁陨石的范围内。

In spite of its low model abundances of the Ningqiang refractory inclusions, high model abundances of olivine aggregates, and high matrix/chondrule volumetric ratio relative to Allende and CV chondrite, the Ningqiang meteorite is a typical oxidizing CV chondrite.

宁强陨石的岩石学、岩石化学特征与CV陨石相应特征相似，尽管宁强陨石具有相对于Allende和CV陨石的较高的富Ca，Al包体、较低的杆拦石集合体的模式丰度和较高的基质/球粒的体积比，宁强陨石仍是一块典型的氧化型CV陨石。

When meteorite hit the Earth surface, it created shockwave to transfer the kinetic energy to the Earth surface. When the speed of meteorite strike reached 10 km/second, the pressure of shockwave can reach several millions bar to compress the target terrane to produce heat, the effect of impact deformation caused by it is several scales stronger than rock intensity, the granite would melt down once the pressure of shockwave reached about 500 thousands bar, the granite would gasify (solid became liquid and meanwhile further became gaseity) once reaching over 600 thousand bar.

当陨石撞击地表时产生冲击波把陨石的动能传给地表，在陨击速度达到10公里/秒时冲击波的压力可达到数百万巴并压缩靶点岩层物质产生热，它产生的冲击变形效应比岩石强度大几个量级，冲击波压力约50万巴时花岗岩就熔化，大于60万巴时花岗岩就气化（在固态转为液态同时进一步转为气态）。

Of Fe , Cu in the metal phase and Mg, Si in the silicate phases to understand the processes of mixing of metal and silicate phases and further decipher the mechanism of formation of mesosiderite;(2) to study in detail the geochemical characteristics of each phase in the meteorite, to provide necessaryevidence for the model of formation of mesosiderite;(3) to study and update in detail the composition of each phase in the meteorite, and provide a new and complete set of data for understanding the mechanism of formation of mesosiderite.

Cu和硅酸盐相中的Mg， Si等中等挥发性元素的稳定同位素进行分析，判断中铁陨石的金属相和硅酸盐相混合过程的环境特征，进而阐明中铁陨石的形成机制；（2）对这块陨石的各相进行详尽的地球化学分析，通过这些相的地球化学关系判断中铁陨石的形成机制，对中铁陨石的形成模型提供必要的制约和证据；（3）全面更新对中铁陨石各矿物相化学成份的认识，为中铁陨石的成因之谜的全面揭开提供最新最完整的数据。

Major element abundances of the silicate phase of the two mesosiderites are similar to those of howardites. The cosmic ray exposure ages are (242± 50) Ma for Dong Ujimqin Qi mesosiderite and (25.4± 5.0) Ma for Weiyuan mesosiderite.

东乌珠穆沁旗及渭源中铁陨石的硅酸盐相在主元素丰度上类似于紫苏钙长无球粒陨石，其宇宙射线暴露年龄分别为(252±50)Ma和(25.9±5.0)Ma。

That is because, among the 10% that are not chondrites, there is a group that is composed almost entirely of metal.

这是因为，在那10%不属于球粒状陨石的陨石中，有一群几乎完全是由金属组成的。

At present there are thirteen well-established chondrites,seven different parent bodies that experienced high temperatures and pervasive melting,and twelve main iron meteorite groups.

本文主要依据现有的资料综述陨石分类，以及来自小行星带、月球和火星等不同类型陨石的宇宙射线暴露年龄及其宇宙化学意义。

The study and comprehensive analysis of static high-pressure quenching experiments and laboratory dynamic high-pressure experiments on chondrites,as well as the study of shock-induced phase transition of minerals in the Suizhou meteorite revealed that the P-T conditions for phase transition of minerals during natural impact events,such as collision of cosmic bodies or impact of meteorites on the Earth′s surface,are not consistent with those obtained by shock experiments on chondrites or rocks in laboratory,...

通过对球粒陨石的静态高压淬火实验和人工动态高压实验的研究和综合分析，以及对在太空中经受过撞击的随州陨石中矿物发生高压相变的研究，查明了自然界的冲击事件，如星体的相互碰撞和陨石对地球表面的撞击中，矿物发生相变的P-T条件与人工冲击波实验的结果并不一致，而与静态高压淬火实验的结果相似，即前者类似静态高压淬火实验，保压时间较长，能产生高压矿物，后者保压时间极短，无高压矿物形成。

The isotopic abundances of rare gases and cosmic-ray exposure ages of asteroid meteorites, planetary meteorites and the Apollo lunar samples applied to clue up and understanding cosmic-ray exposure history of parent bodies of different meteorite types, collision events, the relationship between cosmic-ray exposure ages and heliocentric distance of the parent bodies, irradiation history of precompaction exposure of chondrules, pairing meteorites for the Antarctic meteorites and desert meteorites, the ejection history of planetary meteorites, and relative ages of lunar craters and so on.

小行星陨石、行星陨石及阿波罗月球样品的稀有气体同位素丰度和宇宙射线暴露年龄，已广泛应用于探索和了解不同类型陨石母体的宇宙射线暴露历史、冲击碰撞事件、暴露年龄与日心距离的关系、吸积形成母体前硅酸盐球粒的辐照历史、南极和沙漠陨石中成对陨石的判别、行星陨石的溅射历史及月坑的相对年龄等关键词：宇宙射线暴露年龄；陨石；球粒陨石；无球粒陨石；火星陨石；中铁陨石

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。