Cenozoic unroofing history of the Ladakh Batholith, western Himalaya, constrained by thermochronology and numerical modelling
Cenozoic unroofing history of the Ladakh Batholith, western Himalaya, constrained by thermochronology and numerical modelling
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DOI：
10.1144/0016-76492008-107
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发表时间：
2009-06
影响因子：
2.7
通讯作者：
L. Kirstein;J. Foeken;P. A. van der Beek;F. Stuart;R. Phillips
中科院分区：
文献类型：
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作者：
L. Kirstein;J. Foeken;P. A. van der Beek;F. Stuart;R. Phillips
翻译后摘要：拉达克陨石是Transhimalayan深成带的一部分，作物北部的印度河缝合带。我们认为，拉达克陨石的折返历史与喀喇昆仑山和西藏西南部的构造、岩浆和侵蚀历史有关。我们提出了新的多个低温热年代学数据（锆石（U-Th）/He，磷灰石裂变径迹和磷灰石（U-Th）/He），以深入了解拉达克陨石的冷却历史，并认识到该地区演化的关键时期。从印度河流域向北的年龄减少整个岩基的所有三个温度计应用。提出了一个模型，在拉达克岩岩浆活动停止在始新世晚期和初始剥蚀是由碰撞引起的地形抬升驱动。古近纪晚期岩基向南倾斜。这种倾斜导致了不对称的地形，海拔向北逐渐升高。强烈的侵蚀发生在这个北方地区，而南部边缘的影响，向北逆冲的印度磨拉石。这是第一次，明确的时间和空间变化的折返率确定在这一地区，突出了为什么采样策略是至关重要的记录折返的变化在活跃的构造环境。补充材料：来自拉达克陨石的样品坐标、样品制备和磷灰石颗粒的裂变径迹年龄测量以及颗粒尺寸尺寸可在www.example.com上获得http://www.geolsoc.org.uk/SUP18350。
Abstract: The Ladakh Batholith is part of the Transhimalayan Plutonic Belt, which crops out north of the Indus Suture Zone. We propose that the exhumation history of the Ladakh Batholith is linked to the tectonic, magmatic and erosion history of the Karakoram terrane and SW Tibet. We present new multiple low-temperature thermochronometry data (zircon (U–Th)/He, apatite fission-track and apatite (U–Th)/He) to gain insight into the cooling history of the Ladakh Batholith and recognize key periods in the evolution of the region. From the Indus Valley northwards the ages decrease across the batholith for all three thermochronometers applied. A model is proposed in which magmatism in the Ladakh Batholith ceased in the Late Eocene and initial denudation was driven by topographic uplift caused by collision. Southward tilting of the batholith occurred in the Late Palaeogene. This tilting resulted in an asymmetric topography with increasing elevation to the north. Strong erosion occurred in this northern region whereas the southern margin was affected by northwards thrusting of the Indus Molasse. For the first time, clear temporal and spatial variations in exhumation rate are identified in this region, highlighting why sampling strategy is critical in documenting exhumation changes in active tectonic settings. Supplementary material: Sample co-ordinates from the Ladakh Batholith, sample preparation and fission-track age measurements of apatite grains and grain size dimensions are available at http://www.geolsoc.org.uk/SUP18350.