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对近 5年来国内、外科学家在大别山 苏鲁超高压变质岩带的研究成果进行了剖析 ,并针对具体科学问题进行了深入的讨论 .依据最新资料指出 :(ⅰ )超高压榴辉岩具两类围岩 ,一类为同样经历过超高压变质作用的榴辉岩相岩石 ,另一类为未经历超高压变质的花岗片麻岩 ;(ⅱ )新发现的橄榄石中FeTiO3 的出溶体为 30 0～ 40 0km深度上发生的现象 ,但关键在于证明这种出溶是由于原先在地壳中的橄榄岩被俯冲到 30 0～ 40 0km深度发生的 ,还是本来就在该深度的地幔橄榄岩的相转变 ;(ⅲ )超高压含水矿物相及组合的发现表明流体参与了超高压变质作用 ,但氧、碳、氢同位素研究却表明 ,表壳岩在俯冲到地幔深度时并无大规模流体活动 ,对这一矛盾现象尚需深入研究 ;(ⅳ )对大别山 苏鲁超高压变质岩形成的大地构造背景尚存歧见 ,表现在对诸如是否存在“蛇绿岩” ,超高压变质作用发生的时代 ,大别山下面是否有一古老的地幔楔等问题的争论 ;(ⅴ )对超高压变质岩的折返机制与过程仍无一致的认识 .基于上述讨论 ,今后几年的研究重点将是 :(ⅰ )超高压变质作用的热力学和动力学基础 ;(ⅱ )超高压变质作用与碰撞造山作用的关系及其动力学背景 ;(ⅲ )碰撞造山过程中地壳和地幔以及大陆岩石圈与软流圈之间的相互作用及其对大陆岩石
According to the latest information, (i) There are two types of ultrahigh-pressure eclogites with eclogites Rocks, one is eclogite facies also experienced UHP metamorphism and the other is granitic gneiss experiencing no UHP metamorphism; (ii) the newly discovered olivine has a FeO30 content of 30 However, the key point is that this dissolution is due to the subduction of the peridotites that originally occurred in the crust to depths of 30 0 ~ 40 0 km, or the depths of the mantle peridotite (Iii) The discovery of ultrahigh-pressure water-bearing mineral phases and assemblages indicates that the fluids are involved in the UHP metamorphism, but studies of oxygen, carbon and hydrogen isotopes show that the crust rocks did not have large-scale fluid activities from subduction to mantle depth (Ⅳ) There are still differences on the tectonic setting of the Sulu UHP metamorphic rocks in the Dabie Mountains, such as the existence of “ophiolite”, ultra-high (Ⅴ) there is still no consensus on the mechanism and process of the reentry of UHP metamorphic rocks.Based on the above discussion, the research emphasis in the next few years will focus on the following aspects: (1) Is: (i) the thermodynamic and kinetic basis of UHP metamorphism; (ii) the relationship between UHP metamorphism and orogeny and its dynamic background; (iii) the crust and mantle and the lithosphere and Interaction between asthenosphere and its interaction with continental rocks