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根据札达盆地剖面中地层的接触关系、沉积旋回、沉积体系和岩相岩性特征,可将上新统河湖相地层划分为2个组、5个沉积相、8个岩段。古格组(N22g)一岩段为砾岩,属河流相沉积;二、三、五岩段以细碎屑岩为主,属浅湖相沉积;四岩段以含粘土质细碎屑岩为主,属深湖相沉积。托林组(N21t)一、二、三岩段为一套砾岩、含砾中粗粒钙质长石岩屑砂岩和中细粒砂岩的碎屑岩,为典型冲(洪)积扇沉积物。ESR法和古地磁法测年结果表明,古格组形成时代为上新世晚期(4.40～2.47Ma);托林组形成时代为上新世早期(5.44～4.40Ma)。札达盆地为一同生断陷盆地,在上新世时期的构造运动过程中,盆地演化经历了水进体系域—湖泊扩张体系域—湖泊收缩体系域3个发展阶段。
According to the contact relationship, sedimentary cycle, sedimentary system and lithofacies lithology characteristics of strata in the Zanda Basin, the Upper Pleistocene fluvial and lacustrine facies can be divided into two groups, five sedimentary facies and eight rock sections. The rock block of the Guge Formation (N22g) is conglomerate, which belongs to river facies sedimentation. The second, third and fifth rock sections are mainly composed of fine clastic rock and belong to the shallow lacustrine facies. The four rock sections are composed of clay-bearing fine clastic rocks Mainly belong to deep lacustrine deposition. The primary, secondary and tertiary rocks of the T21 (N21t) Formation are conglomerate, gravel-bearing coarse calcareous feldspathic lithic sandstone and medium fine grained sandstone, Things. The results of ESR and paleomagnetic measurements show that the age of the Guge Formation was late Pliocene (4.40-2.47 Ma), that of the Tuolin Formation was early Pliocene (5.44-4.44 Ma). The Zanda Basin is a syngenetic faulted basin. During the Pliocene tectonic movement, the basin evolution experienced three stages of evolution into syngenetic system of lacustrine system-lacustrine contraction system.