GSA Connects 2021 in Portland, Oregon

Paper No. 168-2
Presentation Time: 1:50 PM

FOREARC AND FORELAND BASIN EVIDENCE FOR PROTRACTED LATE CRETACEOUS-EOCENE COLLISION IN WESTERN ANATOLIA


MUELLER, Megan1, LICHT, Alexis2, CAMPBELL, Clay3, OCAKOGLU, Faruk4, BEARD, K. Christopher5, MÖLLER, Andreas6, AKSIT, Gui7, METAIS, Gregoire8, LOWERY, Kyle9, SHEKUT, Samuel10, COSTER, Pauline11 and TAYLOR, Michael H.3, (1)Department of Earth and Space Sciences, University of Washington, Seattle, WA 98195, (2)Aix-Marseille Université, CNRS, Centre de Recherche et d’Enseignement de Géosciences de l’Environnement (CEREGE), Aix-en-Provence, 13545, France, (3)Department of Geology, University of Kansas, Lawrence, KS 66045, (4)Department of Geological Engineering, Eskisehir Osmangazi University, Eskisehir, 26480, Turkey, (5)Ecology & Evolutionary Biology, University of Kansas, Lawrence, KS 66045, (6)Department of Geology, University of Kansas, Ritchie Hall, Earth, Energy, and Environment Center, 1414 Naismith Dr Room 254, Lawrence, KS 66045, (7)Department of Earth Sciences, University of Oregon, Eugene, OR 97403, (8)Centre de Recherches sur la Paléobiodiversité et les Paléoenvironnements, Muséum National d'Histoire Naturelle, Paris, 75005, France, (9)Seattle, WA 98103, (10)Earth and Space Science, University of Washington, 4000 15th Ave NE, Seattle, WA 98195, (11)Réserve naturelle nationale géologique du Luberon, Apt, 84400, France

Across the Alpine-Himalayan orogeny, the timing of intercontinental collision is difficult to determine and often disputed by ~15 to 40 Myr. This has led to a variety of contradictory paleogeographic and geodynamic reconstructions. In Anatolia, the closure of the Neotethys Ocean and collision along the >1,700 km long Izmir-Ankara-Erzincan suture zone has been proposed to occur sometime from the Late Cretaceous through Eocene. Forearc-to-foreland basins across northern Anatolia preserve a near-continuous depositional record during subduction and collision, and therefore offer unparalleled insight into the evolution of continental collisions. Here we present sedimentary provenance results from Late Cretaceous through Eocene strata in the forearc-foreland basins of western Anatolia. We compare these results to published data from across Anatolia to evaluate the regional response to intercontinental collision. The appearance of lower plate detritus, ophiolitic material and sediment recycling in the forearc preceded thick-skinned deformation and molasse deposition by ~20 Myr, demonstrating a protracted collisional evolution. We synthesize these results into a new scenario for Izmir-Ankara-Erzincan suturing by proposing several geodynamic mechanisms to explain multi-phase intercontinental collision.