The southern Moroccan passive continental margin: an example of differentiated long-term landscape evolution in Gondwana
The ENE-trending Anti-Atlas mountain belt reveals variation in recent topography with elevations of >3km indicating a differentiated long-term landscape evolution. To unravel the subsidence and exhumation history, low-temperature thermochronology has been applied on 21 samples from the Precambria...
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| Main Authors: | , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
2018
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| In: |
Gondwana research
Year: 2017, Volume: 53, Pages: 129-144 |
| ISSN: | 1878-0571 |
| DOI: | 10.1016/j.gr.2017.03.013 |
| Online Access: | Verlag, Volltext: http://dx.doi.org/10.1016/j.gr.2017.03.013 Verlag, Volltext: http://www.sciencedirect.com/science/article/pii/S1342937X17301934 
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| Author Notes: | Manuel Sehrt, Ulrich A. Glasmacher, Daniel F. Stockli, Haddou Jabour, Oliver Kluth |
| Summary: | The ENE-trending Anti-Atlas mountain belt reveals variation in recent topography with elevations of >3km indicating a differentiated long-term landscape evolution. To unravel the subsidence and exhumation history, low-temperature thermochronology has been applied on 21 samples from the Precambrian basement of the Irherm, Kerdous, Ifni, and Bas Drâa inlier. Thermochronological data suggest a common geological evolution of the western Anti-Atlas. Zircon fission-track ages from 287 (±23) to 331 (±24)Ma point to a main exhumation in the Late Carboniferous-Early Permian assigned to the Variscan folding and post-folding erosion. Zircon (U-Th)/He (205-287Ma) and apatite fission-track (120-219Ma) data are related to the Central Atlantic rift and drift stage, as the Anti-Atlas formed the exhumation shoulder of the rift system. The rock uplift and exhumation phase lasted up to the Early Cretaceous, whereby 9km of Precambrian-Palaeozoic overburden has been eroded. Thermal modelling reveals a minor sedimentary burial (1.5-2.5km) throughout the Cretaceous, in accordance with the widespread transgression across the northern Africa in the Cenomanian-Turonian. Apatite (U-Th-Sm)/He ages between 49 (±3) and 164 (±10)Ma confirm recent minor exhumation in the western Anti-Atlas with an increasing impact of the Atlasian orogeny and potentially a mantle plume anomaly from southwest to northeast reflecting the differentiated topography in the area. |
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| Item Description: | Available online 10 April 2017 Gesehen am 01.08.2017 |
| Physical Description: | Online Resource |
| ISSN: | 1878-0571 |
| DOI: | 10.1016/j.gr.2017.03.013 |