3:00 PM - 3:15 PM
[BPT23-17] Paleoproterozoic Ocean Floor Reconstruction Project: II Geology of Cape Three Points area in the Ashanti belt of the
Keywords:Paleoproterozoic, Black shale, volcaniclastics, Birimian belt, Ashanti subbelt
In this study, we focused on the coastal area around Cape Three Points at the southernmost part of the Ashanti (Axim-Konongo) belt in Ghana where excellently preserved Paleoprotorozoic deeper oceanic sedimentary sequences extensively outcrop in the eastern part for over 4km stretch. This volcano-sedimentary sequence are affected by greenschist facies metamorphism.
Structurally, this region preserves S1 cleavage and asymmetrical synform with west vergence and S0 younging to the east. Provisional stratigraphy is very continuous up to more than 1000m thick. There are several coarsening upward characteristics from bedded volcanic sandstone interbedded with black shale. This continuous sequence indicate distal submarine volcaniclastic section in an oceanic island arc around the West African Craton. Preliminary carbon isotope analysis shows δ13C = ? ?43 - ?37‰ for black shale of upper part of the section with the very light isotope being for black shale of euxinic condition such as the Black sea.