Significance of hydrocarbons in anorthite megacrysts from island arc.

碳氢化合物，验证了高温Micro-FTIR，被发现包括在相同的钙长石和拉布拉多巨晶含有自然铜，如第1部分中所述，在玄武质岩石，从日本岛弧和北美西部大陆边缘，分别。钙长石巨晶中Muntz金属（Cu_<60>Zn_<40>）的发现，为休谟-罗瑟里法则在自然界中的确立提供了依据。关于与烃类共存的自然铜的成因，提出了以其纯度和定向分布为依据的出溶模型，并根据奥斯特瓦尔德熟化理论解释了自然铜的晶体生长。虽然大陆边缘和火山弧具有共同的地质和构造背景，但断裂的拉布拉多岩和自形钙长石之间在形态上的显着差异似乎在火山爆发的力量中爆发出来。此外，还证明了钙长石巨晶中的蚀变橄榄石中也含有微量的烃类，对这些烃类的检测表明，结晶钙长石和橄榄石的岩浆中含有相同的烃类。蚀变橄榄石的Fe/Mg比值、钙长石巨晶的Sr含量和Sr同位素比值反映了从日本海沟到弧后的横向变化，其地球化学行为证明钙长石巨晶及其蚀变橄榄石的快速结晶与岛弧下俯冲的地壳成分和板状沉积物密切相关。

Hydrocarbons, verified by high-temperature Micro-FTIR,are found to be included by the same anorthite and labradorite megacrysts containing native coppers, as described in Part 1, in basaltic rocks, from Japanese island arc and in the westem continental margin of North America, respectively. A finding of Muntz metal (Cu_<60> Zn_<40> ) within the anorthite megacryst offerred the establishment of Hume-Rothery's rule in nature. Concerning the genesis of native coppers coexistent with the hydrocarbon, the exsolution model fortified by their purity and oriented distribution has been suggested and can account for crystal growth of native coppers based on the theory of Ostwald ripening. While continental margins and lsland arcs have geological and tectonical backgrounds common to each other, remarkable difference in morphology between fractured labradorites and euhedral anorthites seems to flare up in the power of the volcanic eruption. Moreover it proved that the corroded olivines within anorthite megacrysts hereupon have also a trace amount of hydrocarbons, detection of which discloses that the magmas crystallizing these anorthite and olivines contained the same hydrocarbons. Fe/Mg ratio of the corroded olivines, Sr-content and Sr-isotope ratio of anorthite megacrysts typical of arc-volcanism in Japan afford the lateral variations from the Japan trench to the Back arc side, and their geochemical behavior witnesses the rapid crystallization of anorthite megacrysts and their corroded olivines in close association with the crust components and the slabsediments subducted beneath the island arc.