The southern Moroccan passive continental margin

• Verfasst von: Sehrt, Manuel [VerfasserIn]
• Verfasst von: Glasmacher, Ulrich A. [VerfasserIn]
• Titel: The southern Moroccan passive continental margin
• Titelzusatz: an example of differentiated long-term landscape evolution in Gondwana
• Verf.angabe: Manuel Sehrt, Ulrich A. Glasmacher, Daniel F. Stockli, Haddou Jabour, Oliver Kluth
• Jahr: 2018
• Jahr des Originals: 2017
• Umfang: 16 S.
• Fussnoten: Available online 10 April 2017 ; Gesehen am 01.08.2017
• Titel Quelle: Enthalten in: Gondwana research
• Ort Quelle: Amsterdam [u.a.] : Elsevier, 1997
• Jahr Quelle: 2018
• Band/Heft Quelle: 53(2018), Seite 129-144
• ISSN Quelle: 1342-937X
• DOI: doi:10.1016/j.gr.2017.03.013
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: (U-Th-Sm)/He
• Sach-SW: Fission-track
• Sach-SW: Low-temperature thermochronology
• Sach-SW: Moroccan passive continental margin
• Sach-SW: Subsidence/exhumation history
• Sach-SW: Western Anti-Atlas
• K10plus-PPN: 1561435287

Abstract

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.