Abstract
Mega-streamlined landforms on Earth and Mars have been attributed to aeolian, glaciogenic, fluvial, and tectonic processes. Identifying the forces that shaped these landforms is paramount for understanding landscape evolution and constraining paleo-climate models and ice sheet reconstructions. In Arabia, east-northeast, kilometer-scale streamlined landforms were interpreted to have been formed by Quaternary aeolian erosion. We provide field and satellite-based evidence for a Late Ordovician glacial origin for these streamlined landforms, which were exhumed during the Red Sea–related uplift. Then we use Late Ordovician paleo-topographic data to reconstruct the Late Ordovician ice sheet using identified and previously reported glacial deposits and landforms. Our reconstruction suggests these glacial features are part of a major, topographically controlled, marine-terminating ice stream, twice the length of the largest known terrestrial ice streams. Our results support models that advocate for a single, major, and highly dynamic ice sheet and provide new morphological-based constraints for Late Ordovician climate models.
Red Sea tectonics unveil the largest known terrestrial ice stream: New constraints on Late Ordovician ice sheet dynamics