Journal of Petroleum Geology, Vol.5,
No.3, pp.287-308, 1983
©Copyright 2000 Scientific Press,
Ltd.
MOZAMBIQUE-MADAGASCAR
GEOSYNCLINE,
II: PETROLEUM GEOLOGY
Maurice Kamen-Kaye*
* 1 Waterhouse Street, Cambridge,
Massachusetts 02138, USA.
Abstract
The Mozambique-Madagascar geosyncline may
rank above congeneric borderland downwarps along the western
Indian Ocean in its hydrocarbon exploration quality. On the
Mozambique flank, gas in significant quantities has been produced
on test. On the Madagascar flank, bitumen in equally significant
quantities has been outlined. Exploration of the geosyncline as a
whole has included the drilling of more than 30 wells on the
Mozambique flank, and more than 40 wells on the Madagascar flank.
Of this total of more than 70 wells, 15 exceed 4,000 m in depth.
Objectives almost untouched by the drill are the Karroo strata
below basalt on the Mozambique flank, Karroo strata below marine
Jurassic onlap on the Madagascar flank, and Karroo strata that
this writer believes should exist in continental and mixed facies
at the center (below deep waters of the present Mozambique
Channel). Considerable depth of burial of all these Karroo
objectives should enhance the maturation of their original
organic matter to the hydrocarbon stage, even though that matter
was initially vegetal and palynomorphic. Post-Karroo objectives
may be limited to the geosynclinal flanks, because pelagic facies
may have dominated the center throughout post-Karroo time.
Limitation to the flanks, however, does not adversely affect
depth of burial in many areas. Post-Karroo strata, in fact, may
rival their Karroo predecessors, especially considering the
presence of marine intercalations. Principal exploration
parameters such as sedimentary volume, source rock, reservoirs,
and present density of drilling, are favorable or good. They
suggest that the Mozambique-Madagascar geosyncline is a prospect
worthy of much additional deep drilling to find major reserves of
petroleum.