火山岩

Based on major and trace elements and isotope geochemical data, it is inferred that Sandouding suite is formed by magma melting of Late Archeozoic continent tholeiite source, and its geochemical variation is controlled by hornblende fractional crystallization. Besides fractional crystallization, the geochemical variation of Huanglingmiao suite is related to the mixing between dacitic magma and felsic magma. Dalaoling suite is probably derived from early Precambrian volcanics.

根据岩石化学和同位素组成推断，三斗坪岩套的源岩主要是晚太古代大陆拉斑玄武岩，母岩浆相当于英安质，岩套内的成分变化主要受角闪石分离结晶作用控制；黄陵庙岩套除受分离结晶作用影响外，成分变化主要与英安质母岩浆和某种长英质岩浆的混合有关；大老岭岩套的源岩亦为早前寒武纪火山岩。

The origin of the No. 7 nugget found in south suburbs of Yiyang city of Hunan mainly comes from plaeovolcanic rock and the gold veins and the basic volcanic clastic rock in Nenjiaxi Group slate around the plaeovolcanic rock. Its origin belongs to near source or autochthon sedimentary regeneration.

湖南益阳南郊 7号"狗头金"的金源主要来自古火山岩及其边部冷家溪群板岩中的含金矿脉与基性火山碎屑岩系，属近源甚至近于就地的沉积再生成因。

Tuyon volcanic rocks are classified as alkali series, which are low in silicon, enrichedin alkali, especially enriched in kalium. The types of the volcanic rocks include trachybasalt,basanite, basalt,and phonolitic basalt.

托云火山岩具贫硅富碱，特别是富钾的特点，属于碱性系列，岩石的类型包括粗面玄武岩、碧玄岩、玄武岩、响岩质玄武岩。

Basanite and tephrite from Mt. Crater, Cape Bird and Bonney Lake exhibit similar composition in major elements and trace elements, rare earth elements . They are enriched in MgO, TiO〓, transitional elements and compatible elements , and depleted in SiO〓, Al〓O〓, Na〓O, K〓O, incompatible elements and rare earth elements; Latite from Cape Rodeys and Cape Evens are different from basanite and tephrite, they are enriched in SiO〓, Al〓O〓, Na〓O, K〓O, incompatible elements and rare earth elements, and depleted in Mgo, TiO〓, transitional elements and compatible elements. Volcanic rocks in five regions have the same isotopic ratio of 〓Sr/〓Sr (0.703115-0.703334) and 〓Nd/〓 Nd (0.512892-0.513076), however,〓Pb/〓Pb ratio in volanic rocks from Mt. Crater, Cape Bird and Bonney Lake is lower than those of Cape Rodeys and Cape Evens.

在主元素氧化物和微量元素、稀土元素含量上，克雷克特山、鸟角和博尼湖南岸的碧玄岩、碱玄岩成分比较类似，均具有较高的MgO、TiO〓、过渡元素和相容元素，较低的SiO〓、Al〓O〓、K〓O、Na〓O、不相容元素和稀土元素；罗德角和伊万思角安粗岩雷同，它们具有较高的SiO〓、Al〓O〓、Na〓O、K〓O、稀土元素和不相容元素，较低的MgO、TiO〓、过渡元素和相容元素，但五地区火山岩几乎具有一致的Sr、Nd同位素比值，〓Sr/〓Sr＝0.703115-0.703344、〓Nd/〓Nd＝0.512892-0.513076，在Pb同位素比值上，五地区的〓Pb/〓Pb＝18.664-19.913，其中碧玄岩和碱玄岩比安粗岩的比值稍低。

Armed with this information and further analyses, Rumble, lead author Bekker, and colleagues propose the following scenario today in Science . Early in Earth's history, volcanic eruptions spewed massive amounts of sulfur dioxide into the atmosphere, where UV sunlight broke down the gas and created the odd sulfur isotope ratios. The sulfur descended with the rain and accumulated into sedimentary beds on the sea floor. Once there, superheated water from geothermal vents at various locations on the sea floor cooked the sulfur into sulfide. Finally, nickel-bearing magma welled up from Earth's mantle, combining with the sulfide to form nickel sulfide and encasing the compound inside volcanic rock called komatiite.

凭借这份资料和进一步的分析，朗布尔、研究论文的第一作者贝克及同事们今天在《科学》杂志上提出了如下的推测：在地球早期的历史上，火山爆发将大量的二氧化硫气体喷射到空中，太阳的紫外线将其分解，产生了奇特的硫同位素比值，这种硫随雨降下，积存于海底沉积层中；一旦到达海底，海底各处的地热出口所产生的温度过高的水把硫加热成硫化物；最终含有镍的岩浆从地幔中涌出，跟硫化物结合形成硫化镍，并将硫化镍包裹在一种叫做"科马提岩"的火山岩中。

Aiming at this problem, we collected and analyzed a large number of data and found that the volcanic rocks had a bimodal feature.

对此问题，我们搜集了大量的数据，分析发现火山岩具有双峰特征。

By summing up the cyclicity, rock association and occurrence of volcanic rocks with their overlying and underlying contact relations and forming environment, and concerning the research results of isotope chronology and biostratigraphy, the Yixian formation of the working area may be subdivided into four members.

综合火山岩的旋回性特徵，岩石组合、岩石产出特徵，不同岩石组合的上、下接触关系和岩石形成环境的分析结果，结合同位素年代学及生物地层学的研究成果，区内义县组被划分成了4个岩性段。

127 Ma. These ages suggest problems in stratigraphic correlation, indicate that there is considerable diachroneity in the timing of volcanism and sedimentation in the Middle and Late Jurassic Yanshan orogen, and cast doubt on the traditional interpretation that the Tiaojishan-Tuchengzi sequence is bounded by regional unconformities dated at ca.

这些测年数据说明以往的地层对比是有问题的，燕山造山带在中、晚侏罗世所发育的火山岩和沉积岩地层是穿时的。

Analysis shows that high content of N〓 and He may come from igneous formation of Carboniferous.

研究认为高含量的N〓、He可能来自基底石炭系火山岩系。

A and tectonic environment of Cenozoic volcanic rocks in China.

中国新生代火山岩的年代学与地球化学。

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。