eCite Digital Repository

Crustal structure in the Western Somali Basin


Coffin, MF and Rabinowitz, PD and Houtz, RE, Crustal structure in the Western Somali Basin, Royal Astronomical Society Geophysical Journal, 86, (2) pp. 331-369. ISSN 0016-8009 (1986) [Refereed Article]

Restricted - Request a copy

Copyright Statement

The definitive published version is available online at:

DOI: doi:10.1111/j.1365-246X.1986.tb03832.x


As part of integrated marine geophysical studies in the Western Somali Basin, we performed 118 sonobuoy experiments to define better the crustal structure of the margins and basin created by the separation of Madagascar and Africa. After using T2/X2, conventional slope-intercept methods, and slant-stacked t-p techniques to analyse the data, we combined our solutions with all previous velocity information for the area. Velocity functions were derived for the sediment coiumn, and we detected a high-velocity (4.58 0.29 km s1) sediment layer overlying acoustic basement. We confirmed that the crust is indeed seismically oceanic, and that it may be considered either in terms of a layered model layers 2B (5.42 0.19 km s1), 2C (6.23 0.22 km s1), 3 (7.03 0.25 km s1), and mantle (7.85 0.32 km s1) were identified or a more complex gradient model in which layer 2 is marked by a steeper velocity gradient than underlying layer 3. Integrated igneous crustal thicknesses (1.62 0.22 s, 5.22 0.64 km) are significantly less than what is considered normal. We present a revised seismic transect across the East African margin, as well as total sediment thickness, depth to basement and crustal thickness maps.

Item Details

Item Type:Refereed Article
Keywords:crustal structure;East Africa;Madagascar;sonobuoy;Tp inversion
Research Division:Earth Sciences
Research Group:Geology
Research Field:Marine geoscience
Objective Division:Expanding Knowledge
Objective Group:Expanding knowledge
Objective Field:Expanding knowledge in the earth sciences
UTAS Author:Coffin, MF (Professor Mike Coffin)
ID Code:73769
Year Published:1986
Web of Science® Times Cited:28
Deposited By:Research Division
Deposited On:2011-10-25
Last Modified:2011-11-09
Downloads:12 View Download Statistics

Repository Staff Only: item control page