同位素

Cryptoexplosive breccia and cryptofelsite was derived from comagmatic source, as the products ofdifferent phases of a certain magmanism.

稀土元素、微量元素、同位素等地球化学特征显示出成矿物质和成矿热液与隐爆角砾岩、霏细岩同源，成岩与成矿是同一岩浆作用不同阶段的产物。

This ratio of isotopes transfers to rainwater. When Coryphodon drank, the oxygen atoms became incorporated into its tooth enamel.

这种同位素的比例会带进雨水中，当冠齿兽饮水时，氧原子会融入牙齿的珐琅质。

Accelerator mass spectrometry has ultra-high sensitivity and can be used to detect extremely low impurity contents in samples. 10Be is a cosmogenic nuclide. As a tracker, it has been widely applied to earth, environmental and cosmographic sciences.

加速器质谱计具有很高的灵敏度，能测量样品中含量极微的杂质同位素。10Be是一种宇宙成因核，在地学、环境科学和宇宙学等领域有广泛的应用，它为纯β衰变核，端点能量低且半衰期很长。

Ca is widely abundant in nature and its rodioisotope 41 Ca is a cosmogenic nuclide with a half\|life of 10 5 years. However, the 41 Ca/ 40 Ca ratio in natural samples is very low and can only be measure d by accelerator mass spectrometry. The application of 41 Ca is ve ry i mportant not only in the life science but also in geological dating, global envi ronment change studies and astrophysics.

1 引言Ca在自然界中广泛存在，它不仅是人体中含量最丰富的元素之一[1] ，也是众多其他物质的组成部分。41Ca(半衰期为 1.0 3× 10 5a)属于Ca的放射性同位素中的一种，其衰变方式为轨道电子俘获，只发射3.3keV的X射线，天然样品中41Ca 40 Ca的值很小。

This thesis studies the volcanic tectono-petrofacies, petrology, mineralogy, geochemistry, isotopic chronology, stratum and high-precision SHRIMP zircon U-Pb datings of the Mt.Yandangshan volcano-intrusive complex, and concludes that: Yandangshan volcanic rock units belong to high-K calc-alkaline acid rock associations, mainly ryholitic and trachytic dacitic in composition. They have A/CNK values of 0.9-1.2 (i.e., aluminium saturation and supersaturation), enriched LREE and LILEs and depleted HFSE. Their 8Eu values are 0.11-0.32, indicating a evident fractional evolution of plagioclase crystallization. Their ∑REE varied very limitedly,(87~Sr/(86)Sri ratios and eNd values are 0.7086～0.7095 and -10.20～-9.96 for volcanic rocks, and 0.7087~0.7095 and -7.6～6.92 for the central intrusive facies syenite, which means that all the igneous rocks from Mt. Yandangshan are evolutional products of magmas with the same source, and that they derived mainly from crust, but mixed with mantle components.

本文从火山构造岩相学、岩石学、矿物学、地球化学、同位素年代学、地层学等方面出发，同时结合高精度SHRIMP锆石U-Pb定年，对雁荡山火山岩进行了系统的研究，确定雁荡山火山岩为一套以流纹质和粗面英安质为主体的高钾钙碱性酸性岩石组合，A/CNK值集中在0.9～1.2之间，为铝饱和或铝过饱和类型；富轻稀土元素和大阳离子亲石元素、相对亏损高场强元素：负铕异常明显，δEu值为0.11～0.32，表明岩浆经历了以斜长石为主的强烈结晶分异作用：岩石样品的∑REE变化有限，火山岩样品的~(87Sr/~(86)Sr_i为0.7086～0.7095，εNd为-10.20～-9.96，中央侵入体石英正长岩~(87Sr/~(86)Sr_i为0.7087～0.7095，εNd为-7.6～-6.92，表明它们是同源岩浆分异演化的产物，物质来源主要为陆壳，但有地幔物质参与。

Thrissakarnrnalensis was the basal pelagic phytoplankton feeder,while Trachurus japouicu was commonly feed in seagrass circumstance.GC/C-IRMS analysis was applied to fish,zooplankton and demersal species.

建立GC/C-IRMS技术测定生物体单分子脂肪酸碳稳定同位素的方法，应用于长江口毗邻海域主要生物种类带鱼、小黄鱼、黄鲫等海洋鱼类，桡足类、箭虫、水母等浮游动物，中国毛虾、周氏新对虾、中华管鞭虾等底栖生物的研究。

With desaturation increases,δ~(13)C-FA values decline.

单分子脂肪酸的碳同位素特征与聚类分析手段结合，能够更准确辨别生产者和消费者之间的捕食关系。

As a result, biotically enhanced weathering generated carbon-bearing soils on a large scale and their detrital sedimentation sequestered carbon.

结果就是，由生物强烈影响的风化作用产生了大范围的含碳土壤，同时碎屑岩中保存了被隔离的碳同位素。

As for sulfur isotopic composition, the general feature of two types deposits is a single peak distribution. All δ〓s values of the ores are near zero. The difference of different deposits lies in that the δ〓s values (1. 8-5. 2‰) of LDT are of small positive value and are similar to that of the metamorphic rocks and dioritic porphyrites in the region while the δ〓s values of SDT are always near zero. Features above suggest that two types of deposits have closely genetic relationship to metamorphic and magmatic rocks.

硫同位素组成上，两类金矿床共同的特征是均具有明显的单峰塔式效应，且δ〓S值均位于0值附近不大的变化范围内；不同的是，近程式金矿的δ〓S平均值均接近于0，与该类金矿具密切成因联系的岩体的δ〓S值也接近于0值，而远程式金矿的δ〓S平均值均为小的正值，变化范围为1.8～5.2‰，区内太古代变质岩及矿区内闪长玢岩脉的全岩δ〓S值位于这一区间内，反映了远程式金矿床其成矿物质不仅来源于重熔岩浆，同时还可能部分来源于变质岩围岩。

It is suggested that the dioritic enclaves and their host granite were derived from the same parental magma that resulted from partial melting of the Neoprot-erozoic depleted-mantle-sourced juvenile crust.

综合岩石学、地球化学和同位素等方面的对比研究，笔者认为八大石闪长质包体属于同源包体，为寄主花岗岩同源母岩浆经结晶分异作用形成的早期产物

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷