Type Oceanographic cruise
Ship Pourquoi pas ?
Ship owner Ifremer
Dates 19/03/2016 - 03/04/2016
Chief scientist(s) MOULIN Maryline ORCID, EVAIN Mikael ORCID



Technopôle Brest-Iroise

Place Nicolas Copernic

29280 Plouzané

DOI 10.17600/16009500
Objective Few continental margins (divergent, strike-slip or transform) have been studied with an integrated approach, taking into account the crustal structural architecture and sediment stratigraphy from the onshore drainage basins to the abyssal plain. The aim of the PAssive Margin Exploration LAboratory (PAMELA) project, conducted by TOTAL, IFREMER, and French Universities), and focusing on the analysis of the Mozambique Channel, is to derive a lithosphere-scale evolutionary model of this area following a « source @ sink » ' « Mud @ Mantle » approach. This comprises a characterisation of 1) its structure (crustal and sedimentary), 2) its genesis, the vertical evolution (subsidence, exhumation), and its associated deformation, all within a detailed and accurate plate kinematic framework, 3) its sedimentary systems, from the deltas to the distal turbiditic lobes, sediment sources and links to dynamic topography, palaeo-climatic variations and palaeo-currents. The MOZ3-5 project and cruise are focusing on the crustal structure and architecture of the East Limpopo and Natal Valley passive margins and the segment linking these two basins. During the cruise we acquired multichannel (360 traces) and wide-angle seismic data, using Ocean Bottom Seismometers (OBS), supplemented by gravity and magneti data. Swath multibeam, singlebeam echosouder, sediment sounder (Chirp 1.8-3.5.3 kHz) were additionally acquired. Some sedimentary and rock samples using piston coring and a dredge were acquired due to leftover time. One of the main objectives of this cruise is : to image the structure of a strike-slip margin, in order to discuss the nature of the crust below the Natal valley and Limpopo basin; to determine the position of the first oceanic crust; to conclude about its pre and post-rift evolution of the margin: which impact has the volcanism on the vertical evolution of the margin?; to test, confirm or eventually falsify the different palinspastic reconstructions of the Indian Ocean, and models of passive margins genesis, which are found in the literature. Particularly we are aiming to better understand the transition between a strike-slip margin (East Limpopo) and a pull-apart divergent margin (North Natal) and to compare with similar structural settings around the world in order to test ifs the mechanism of crustal and lithospheric) thinning reveals similarities for both margin types.

Published data

Evain Mikael, Schnurle Philippe, Lepretre Angélique, Verrier Fanny, Watremez Louise, Thompson Joseph Offei, De-Clarens Philippe, Aslanian Daniel, Moulin Maryline (2021). Crustal structure of the East-African Limpopo Margin, a strike-slip rifted corridor along the continental Mozambique Coastal Plain and North-Natal Valley.

Data managed by SISMER