Deep Crustal Structure of the North-West African Margin from Combined Wide-angle and Reflection Seismic Data (MIRROR Seismic Survey)
|Author(s)||Biari Youssef1, 2, 4, Klingelhoefer Frauke1, Sahabi Mohamed2, Aslanian Daniel1, Schnurle Philippe1, Berglar K.3, Moulin Maryline1, Mehdi K.2, Graindorge D.4, Evain Mikael1, Benabdellouahed Massinissa1, Reichert C.3|
|Affiliation(s)||1 : IFREMER, Dept Marine Geosci, ZI Pointe Diable, CS10070, F-29280 Plouzane, France.
2 : Univ Chouaib Doukkali, Lab Geosci Marines & Sci Sols, Fac Sci, URAC 45, El Jadida 24000, Morocco.
3 : BGR, Geozentrum Hannover, D-30655 Hannover, Germany.
4 : IUEM, UMR Domaines Ocean 6538, F-29280 Plouzane, France.
|Source||Tectonophysics (0040-1951) (Elsevier Science Bv), 2015-08 , Vol. 656 , P. 154-174|
|WOS© Times Cited||10|
|Keyword(s)||Moroccan continental margin, Wide-angle seismic modeling, Deep crustal structure, Ocean continent transition|
|Abstract||The structure of the Moroccan and Nova Scotia conjugate rifted margins is of key importance for understanding the Mesozoic break-up and evolution of the northern central Atlantic Ocean basin. Seven combined multichannel reflection (MCS) and wide-angle seismic (OBS) data profiles were acquired along the Atlantic Moroccan margin between the latitudes of 31.5° and 33° N during the MIRROR seismic survey in 2011, in order to image the transition from continental to oceanic crust, to study the variation in crustal structure and to characterize the crust under the West African Coast Magnetic Anomaly (WACMA).The data were modeled using a forward modeling approach. The final models image crustal thinning from 36 km thickness below the continent to approximately 8 km in the oceanic domain. A 100 km wide zone characterized by rough basement topography and high seismic velocities up to 7.4 km/s in the lower crust is observed westward of the West African Coast Magnetic Anomaly. No basin underlain by continental crust has been imaged in this region, as has been identified north of our study area. Comparison to the conjugate Nova Scotian margin shows a similar continental crustal thickness and layer geometry, and the existence of exhumed and serpentinized upper mantle material on the Canadian side only. The oceanic crustal thickness is lower on the Canadian margin.|