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发育在冈底斯岩浆弧与雅鲁藏布江蛇绿岩带之间的日喀则群是残留型弧前盆地沉积。盆地的南部基底和前缘脊由雅鲁藏布江蛇绿岩带构成。盆地形成初期是一套蛇绿质碎屑沉积即冲堆组,沉积物源主要来自盆地南部前缘脊;盆地发育中期主要是一套浊流成因的深海扇,沉积物源主要来自盆地北部的岩浆弧,少量来自前缘脊蛇绿岩;盆地发育晚期为一套浅海-滨海沉积,物源来自北部岩浆弧。至始新世末期或渐新世早期,盆地结束沉积。
The Shigatse group, developed between the Gangdise magma arc and the Yarlung Zangbo ophiolite zone, is a residual foreboding sedimentary basin. The southern basement and ridge of the basin are composed of the Yarlung Zangbo ophiolite belt. In the early stage of basin formation, a set of ophiolite-clastic sedimentary heap stacks, the sedimentary source mainly comes from the southern front ridge of the basin; in the middle of the basin, it is mainly a set of deep-sea fan with turbidite origin. The sedimentary source mainly comes from the northern part of the basin Magma arc, a small amount from the front ridge ophiolite; late basin developed a set of shallow sea - coastal sediments, the source from the northern magmatic arc. Eocene to late Eocene or Oligocene, the basin ended deposition.