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近期,法国A.Nicalas撰文(载于Natune,1985,Vol.315,No.6015,pp.112—115)提出,在大陆裂谷作用的一定条件下,即堆积有巨厚沉积物的裂谷盆地处于大陆岩石圈转化为大洋岩石圈的过渡阶段时,可以产生一种不同于陆壳和洋壳的新类型地壳。这种新类型地壳由巨厚的沉积物组成,底部已变质为绿片岩相或角闪岩相,且有镁铁质岩床和岩颈侵入;直伏其下的为异常地幔(波速≈7.5km/s),由炽热橄榄岩和/或部分蛇纹石化(15—20％)橄榄岩构成。
Recently, the article by A. Nicalas of France (published in Natune, 1985, Vol.315, No.6015, pp.112-115) proposed that under certain conditions of the continental rifting, that is, the rift that is deposited with huge deposits When the basin is in the transitional stage from continental lithosphere to oceanic lithosphere, a new type of crust different from continental and oceanic crust can be produced. This new type of crust is composed of very thick sediments, the bottom has metamorphosed into greenschist facies or amphibolite facies, with mafic bed and rock neck intrusion; under the direct volcanic anomaly mantle (wave velocity ≈7.5km / s), composed of hot peridotites and / or partially serpentinite (15-20%) peridotites.