Planar landforms as markers of denudation chronology: an inversion of East Pyrenean tectonics based on landscape and sedimentary basin analysis
Planar landforms as markers of denudation chronology: an inversion of East Pyrenean tectonics based on landscape and sedimentary basin analysis
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平面地貌作为剥蚀年代学的标志：基于景观和沉积盆地分析的东比利牛斯构造反演
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
Y. Gunnell
中科院分区：
文献类型：
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作者：
M. Calvet;Y. Gunnell
半个多世纪以来，比利牛斯山脉一直被认为是挤压构造古老(前渐新世)的山脉，但由于新近纪晚期的构造抬升，地形变得年轻。有足够的时间让“准平原”在低海拔形成，经历垂直隆起，并在高海拔部分保留到现在。自那以后，这种地形增长模式受到了其他理论的挑战。其中一个假设是，活动造山带的地形处于稳定状态，因此山脉必须是单旋回的，其准平原必须是在大陆汇聚期间由于前陆基准面上升而形成的高海拔地区。在这里，我们使用一系列证据来研究比利牛斯剥蚀年代学，包括物源地层学、地形和构造特征之间的交叉关系，以及基于动物群和植物群化石的风化岩年龄。我们发现，东比利牛斯山经历了一个断断续续的地形演化，直到最近，主要是由构造作用力驱动的，包括12 Ma后的千米级岩石和地表隆起。气候和海平面输入是辅助驱动机制。
Abstract For over half a century the Pyrenees were considered to be a mountain range in which compressional structures were ancient (pre-Oligocene) but topography was young due to late Neogene tectonic uplift. Sufficient time had been afforded for a ‘peneplain’ to form at low elevations, undergo vertical uplift and remain partially preserved at high elevations until present times. This model of topographic growth has since been challenged by alternative theories. One of these postulates that topography in active orogens is in a steady-state, hence mountain ranges must be monocyclic and their ‘peneplains’ must have formed at high altitudes during continental convergence as a result of raised foreland base levels. Here we investigate Pyrenean denudation chronology using a range of evidence including provenance stratigraphy, the cross-cutting relations between topographic and tectonic features, and the age of regolith based on fossil faunas and floras. We find that the Eastern Pyrenees underwent a punctuated topographic evolution until recent times driven primarily by tectonic forcing, including kilometre-scale rock and surface uplift after 12 Ma. Climatic and eustatic inputs were subsidiary driving mechanisms.