摘要
运用裂变径迹年代学方法对青藏高原东南缘中甸地区三叠系的5件磷灰石样品的低温热年代学特征进行分析,获得样品的热演化史,并约束研究区的构造隆升剥露过程.样品的热史模拟结果表明,磷灰石样品基本反映了相同的低温段热演化史.所有样品在沉积后所经历的埋藏温度曾经高于最大退火温度,表明所有样品在记录径迹前都曾完全退火.磷灰石裂变径迹温度-时间轨迹表明,研究区的构造隆升主要集中在2个时间段,即10.2～5.2 Ma B.P.和5.2 MaB.P.至今.5.2 MaB.P.以来的构造隆升事件对整个研究区剥露过程的影响相当广泛,表明研究区在上新世时期曾经历区域性的快速构造隆升事件;所有样品在上新世（5.2Ma B.P.左右）都经历了一次快速的隆升,表明研究区在上新世经历了一次快速构造隆升剥露过程.
Fission track analysis is carried out for 5 apatite samples from Triassic strata on the southeastern margin of the Tibetan Plateau in the Zhongdian region. The study not only presents the thermal evolution history of the study area, but also describes the tectonic uplift and exhumation process of the study area. The simulation results show that the thermal history of the studied apatite samples basically reflect the same thermal evolution history. The apatite fission track T-t paths show that the tectonic uplift of the study area is mainly concentrated in two time periods, namely 10.2-5.2 Ma B.P. and 5.2 Ma B.P. so far. The impact of the exhumation process of the tectonic uplift since 5.2 Ma B. P. is quite extensive, showing that the study area experienced a regional rapid tectonic uplift in the Pliocene. The fission track ages of all apatite samples are younger than their respective strata ages. This shows that the maximum burial temperatures of these samples exceeded the total annealing temperatures of the fission tracks. All samples have experienced a rapid uplift in the Pliocene （5.2 Ma）, showing that the study area has experienced a rapid tectonic uplift and exhumation process in the Pliocene.
出处
《成都理工大学学报（自然科学版）》
CAS
CSCD
北大核心
2014年第2期227-236,共10页
Journal of Chengdu University of Technology: Science & Technology Edition
关键词
青藏高原
裂变径迹
热史模拟
构造隆升
Qinghai-Tibet Plateau fission track thermal history tectonic uplift
