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札达盆地是中新世9.5Ma以来发育的新生代沉积盆地.沉积厚度、砾石成分和古流向分析显示札达盆地新生代沉积的物源主要来自盆地北部的阿伊拉日居山系.札达盆地系列样品碎屑锆石裂变径迹年龄结构显示存在两个明显的峰值年龄区间,分别为12.6～15.3Ma(P1峰值年龄)与19.8～22.2Ma(P2峰值年龄).锆石裂变径迹年龄的滞后时间(lagtime)与沉积时代对比分析显示,P1和P2峰值年龄为快速冷却事件的静态峰,与北部阿伊拉日居地区基岩U-Pb年代研究揭示的热事件时间具有良好的可对比性.因此,札达盆地碎屑裂变径迹年龄两个峰值年龄区间记录了源区阿伊拉日居的两次构造事件,可能对应于喀喇昆仑断裂在中新世的两次强烈的构造活动.综合碎屑锆石、磷灰石裂变径迹年龄信息,估算源区在32.6～9.5Ma之间的平均冷却速率是15.4℃/Ma,上新世末期-第四纪(3.6～1.4Ma)之间再次发生了一次快速的隆升剥露事件.札达盆地中新生代沉积地层碎屑裂变径迹热年代学结构与喀喇昆仑断裂东南段阿伊拉日居的热事件年龄格局吻合,从碎屑裂变径迹年代学角度揭示了造山带地区的盆山耦合过程.
The Zanda Basin is a Cenozoic sedimentary basin developed since the Miocene 9.5Ma.The sedimentary thickness, gravel composition and paleocurrent direction analysis show that the source rocks of the Cenozoic sediments in the Zanda Basin originate mainly from the Airah Habitat in the northern part of the basin. Zircon fission track age structures of the samples from the basin series show two distinct peak age intervals of 12.6-15.3 Ma (P1 peak age) and 19.8-22.2 Ma (P2 peak age), respectively. Zircon fission track age The comparative analysis of lagtime and sedimentary age shows that the peak ages of P1 and P2 are the static peaks of the rapid cooling event, which is in good agreement with the thermal event time revealed by the U-Pb dating of bedrock in the northern Ailajuri area Therefore, the two tectonic events of the Aira diurnal area in the source area were recorded at two peak ages in the Zhada basin, probably corresponding to the two strong Tectonic activity.According to the age information of zircon and apatite fission track, the average cooling rate in the source region from 32.6 to 9.5 Ma is estimated to be 15.4 ℃ / Ma, from the Late Pliocene to Quaternary Ma) happened again Rapid uplift and detritiation events.The zonal geochronology of the Mesozoic-Cenozoic sedimentary strata in the Zanda Basin coincides with the thermal event ages of the Ailajiluju southeast section of the Karakorum Fault. From the fission track Geochronology reveals the basin-mountain coupling process in the orogenic belt.