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将该区内的高喜马拉雅结晶岩划分为南部的角闪岩相岩石和北部的中低压麻粒岩相岩石，后者沿那木拉逆冲断层向南推覆于前者之上。高压麻粒岩相岩石仅以残余产出于后者，主要包括石榴石蓝晶石片麻岩和石榴石透辉石岩。前者的峰期矿物组合为石榴石＋蓝晶石＋三元长石＋石英＋金红石；后者的峰期组合为石榴石（铁铝榴石１０±钙铝榴石＞８０）＋透辉石＋石英＋方柱石＋榍石（Ａｌ２Ｏ３为４％—４．５％）。变质温压估计结果表明高压麻粒岩相岩石形成于大约１．７—１．８ＧＰａ，８９０℃，然后经历了近等温降压变质作用至０．５±０．１ＧＰａ，８５０±５０℃。它们的原岩可能是大理岩及泥质岩。这表明在区内曾存在一高压麻粒岩带，那木拉冲断层可能是高喜马拉雅结晶岩内的一条重要的构造界线。
The high Himalayan crystalline rocks in the area are divided into amphibolite facies in the south and medium- and low-pressure granulitic facies rocks in the north, which are pushed southward over the former along the Namura thrust. High-pressure granulite-facies rocks are only produced with the residual yield, mainly including garnet kyanite gneiss and garnet diopside. The former peak mineral assemblage is garnet + kyanite + ternary feldspar + quartz + rutile; the latter is a combination of garnet (almandine 10 ± garnet> 80) + diopside + Quartz + pagoda + 榍 stone (Al2O3 4% -4.5%). Metamorphism temperature and pressure estimation results show that the high-pressure granulite facies formed at about 1.7-1.8GPa and 890 ℃, and then experienced nearly isothermal descending metamorphism to 0.5 ± 0.1GPa and 850 ± 50 ℃. Their original rock may be marble and argillaceous. This indicates that there was a high-pressure granulite belt in the area. The Namla thrust fault may be an important tectonic boundary in the high Himalayan crystalline rock.