摘要:苦橄岩和科马提岩都是富镁的超镁铁质火山岩，早先，学术界大多关注它们之间的相似性，而对于它们之间的差异性很少强调。于是认为二者的地球化学性质近似，成因类似，形成条件类似。本文采用全数据模式的研究方法，从数据库收集了全球太古宙全部科马提岩和后太古宙全部苦橄岩数据，对比的结果表明，太古宙科马提岩与后太古宙苦橄岩完全不同，它们之间几乎没有可比性。科马提岩与苦橄岩，不仅地球化学特征不同，而且成因不同，形成条件不同，产出时代不同，源区组成也不同。这种不同，反映了太古宙和后太古宙不可能属于同样的构造体制。太古宙是火球时代， 地球异常的热， 主导的可能是静止盖幔构造（stagnant lid tectonics）；后太古宙是热球时代，地球相对冷了许多，主导的是板块构造（plate tectonics）。科马提岩在太古宙广泛出露，无需地幔柱模式；而苦橄岩在后太古宙很少出露，才真正需要地幔柱模式。?
关键词: 苦橄岩/
科马提岩/
全数据模式/
太古宙/
后太古宙/
静止盖幔构造/
板块构造
Abstract:Both the picrite and komatiite are Mg-rich ultramafic volcanic rocks. In the past, most of the academic community paid attention to the similarities between picrite and komatiite, but the differences of them were little concerned. So these scholars considered that picrite and komatiite were similar in geochemical properties, origin, and forming conditions. In my study, the method of whole data has been adopted to analyze the differences between the Picrite and Komatite through the global database. However, the result of the research shows that there are almost no comparisons between picrite and komatite. Picrite and Komatiite are not only different from the geochemical characteristics, but also from their genesis, forming conditions, age, and composition of the source region as well. Since the Archaean was the fireball era and the earth’s extremely hot, the dominant structure might be stagnant lid tectonics. In Post-Archean era, the earth was relatively cold and dominated by plate tectonics. The komatiite is plentifully exposed in the age of Archean, so it is no need for the mantle plume model. On the contrary, the picrite is rarely seen in the Post-Archean and it needs this model.?
Key words:Picrite, Komatiite/
Whole data/
Archean/
Post-Archean/
Stagnant lid tectonics/
Plate tectonics/
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