The marine geology of the one-nautical-mile, exclusive zone around Robben Island, South Africa

A study of Robben Island's one-nautical-mile exclusive zone reveals a pervasive northwest-southeast regional fabric formed by oblique transpression and metamorphic alteration of marine sediments in a deepening fore-arc basin. This finding, consistent with onland studies, sheds light on the poorly understood structural and tectonic setting of the Malmesbury Group rocks that form the island's base. The research utilized ultra-high-resolution bathymetric and marine magnetic data, significantly expanding the mapped area of Tygerberg Formation rocks to 21.8 km² and improving the resolution of the Late Cretaceous Cape Peninsula – False Bay dolerite dyke swarm. These data, synthesized with previous sidescan sonar data, provide new insights into the complex geological history of this UNESCO World Heritage Site.

MacHutchon, M. R., & Van Den Bossche, P. (2018). The marine geology of the one-nautical-mile, exclusive zone around Robben Island, South Africa. South African Journal of Geology, 121(2), 141–156. https://doi.org/10.25131/sajg.121.0005