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雅鲁藏布江南岸有一条规模巨大的超基性岩带已为人们所知,作者于1979年6月在西藏日喀则地区白朗附近的蛇绿岩带南部发现了一套很好的混杂岩。白朗蛇绿混杂岩分布在白朗西南侧到罗布江孜村之间。该地的蛇绿岩自下而上包括超基性岩、基性岩、中基性火山岩、枕状熔岩和深海相放射虫硅质岩等(图版Ⅱ-4、5),属保存较好的有序型蛇绿岩套。蛇绿岩带南侧为浅变质的中生界复理石带,由灰色、灰黑色的砂、板岩组成。蛇绿岩带与变质中生界之间为断层接触,并且被一套以红色为主的杂色砾岩不整合覆盖。蛇绿岩带之北侧为晚白垩世的日喀则群,是由一套灰色、黄绿色的砂、页岩地层组成的复理石。蛇绿岩带与日喀则群之间也为断层接触。
It is known that there is a large ultramafic rock belt on the south bank of the Brahmaputra. In June 1979, the authors discovered a good set of melanges in the southern part of the ophiolite belt near Bailong, Shigatse region, Tibet. Paleozoic ophiolite mélanges are distributed between the southwest of Paklang and Lo-Giang village. The ophiolite in this area includes ultrabasic rock, basic rock, medium-basic volcanic rock, pillow-shaped lava and deep-sea radiolarian siliceous rock from bottom to top (plates Ⅱ-4,5) Ordered ophiolite suite. On the south side of the ophiolite zone is a super-metamorphic Mesozoic complex belt composed of gray, gray-black sand and slate. The ophiolite zone is fault-contacting with the metamorphic Mesozoic and is unconformably covered by a suite of variegated conglomerate that is predominantly red in color. The northern side of the ophiolite zone is Late Cretaceous Shigatse, which is composed of a set of gray, yellow-green sand and shale formations. Between the ophiolite belt and the Shigatse group is also fault-contact.