EES Departmental Seminar - Marina Dottore Stagna, Graduate Student Symposium

Marina Dottore Stagna
Ph.D. Candidate
Department of Earth and Environmental Sciences
Dalhousie University

Title: External Controls on Deep-Water Sediment Deposition in Offshore Tanzania

Abstract: The East African Rift System (EARS) is a modern example of a divergent plate boundary at the early stages of development. Recently, the existence of an offshore branch of the EARS in the western Indian Ocean was proposed, however, its timing of formation and influence on the deep-water depositional systems have been so far poorly explored.

For my Ph.D. project, I use 2D-3D seismic reflection data and exploration wells to provide new tectonic constraints on the offshore branch and investigate its impact on deep-water depositional environments. The goal is to shed light on processes and products of EARS tectonics on the growth of the Tanzanian margin since the Oligocene.

By quantifying the evolution of deep-water drainage networks, I reconstructed the Neogene uplift of Pemba and Zanzibar islands, proposing a new tectonic and paleogeographic model for the region. Then, I investigated the impact of a large-scale submarine landslide triggered by EARS tectonics on sediment transport and deposition to understand the response of slope environments to such giant events. At the end of the talk, I will present preliminary results on a newly recognized offshore graben which origin can be traced back to the Pliocene and it is still affecting modern submarine channel development.

Biography: Marina Dottore Stagna is a Ph.D. candidate in her 4th year in the Department of Earth and Environmental Sciences at Dalhousie University. She received her BSc in Structural Geology in 2017 and her MSc in Marine Geology in 2019 at the University of Naples "Federico II" (Italy). Her master thesis focused on the seismic characterization of the Messinian Evaporite Sequence and associated collapse structures offshore Lebanon, performed in cooperation with the University of Aberdeen (Scotland, UK). In 2020, she joined the MarGinS Lab team to pursue her Ph.D. in Earth Sciences. Her thesis research aims to provide new insights on the evolution of an offshore branch of the East African Rift System along the Tanzania margin and its impact on deep-water depositional systems with the primary goal of better understanding processes and products of continental rifting.



Format: In-person
Milligan Room, 8th Floor Biology-Earth Sciences Wing, Life Sciences Centre, Dalhousie University