Apatite single‐grain (U‐Th)/He data from Heimefrontfjella, East Antarctica: Indications for differential exhumation related to glacial loading?
Apatite single‐grain (U‐Th)/He data from Heimefrontfjella, East Antarctica: Indications for differential exhumation related to glacial loading?
复制标题
来自东南极洲 Heimefrontfjella 的磷灰石单颗粒 (U-Th)/He 数据：与冰川负荷相关的差异折返的迹象？
DOI：
--
复制
发表时间：
2008
期刊：
影响因子：
--
通讯作者：
U. Schwarz
中科院分区：
文献类型：
--
作者：
B. Emmel;J. Jacobs;P. Crowhurst;A. Austegard;U. Schwarz
利用两个剖面的单颗粒（U-Th）/He年龄重建了东南极Heimefrontfjella基底岩石的后二叠纪构造热历史。从晚石炭世/早二叠世沉积盖层下采集的一个样品的（U-Th）/He年龄表明，侏罗纪-早白垩世基底古温度为40°-60 ° C，这是由于后二叠世埋藏造成的。Sivorgfjella剖面样品的磷灰石裂变径迹和（U-Th）/He分析表明，在2087 Ma之后存在一段与弯曲相关的倾斜期。使用（U-Th）/He数据的正演和反演模型进一步限制时间。模型结果表明，新生代阶段的相对快速冷却，从40°C到表面温度。作为驱动机制，我们建议弯曲均衡反弹由于冰川负荷的发展过程中的内陆冰盖腹地的Heimefrontfjella地区。
Single‐grain (U‐Th)/He ages from two profiles were used to reconstruct the post‐Permian tectonic‐thermal history of basement rocks in Heimefrontfjella, East Antarctica. The (U‐Th)/He ages from one sample collected below the late Carboniferous/Early Permian sedimentary cover rocks indicate Jurassic–Early Cretaceous basement paleotemperatures of ∼40°–60°C due to post‐Permian burial. Combined apatite fission track and (U‐Th)/He analyses from samples of a profile in Sivorgfjella suggest a period of flexural‐related tilting after ∼87 Ma. The timing was further constrained using forward and inverse models of the (U‐Th)/He data. Model results indicate a Cenozoic phase of relatively rapid cooling from ∼40°C to surface temperatures. As the driving mechanism, we propose flexural isostatic rebound due to glacial load during the development of the intracontinental ice sheet in the hinterland of the Heimefrontfjella region.