stripes
The Käyser dyke swarm is located in western and south-western Suriname hosted by coarse-grained biotite granite, leucogranite, and felsic metavolcanics. The dykes trend NW-SE and extend for a distance of more than 300 km. They are no more than 50 m wide and are relatively straight implying a tectonic control during intrusion. The dykes are classified as alkaline olivine dolerite containing equal parts labradorite and mafic minerals: augite and olivine of a wide compositional range (e.g. Fo63Fa37 and Fo39Fa61). Additional minerals of note are kaersutite and baddeleyite. Dating is coeval with the African Essakane and Sambarabougou dyke swarms with a similar strike in a Amazonia – West African reconstruction, suggesting the suites are actually part of a large 1500 x 1500 km event. Whole rock major and trace element data and petrographic information can be found in de Roever et al. (2003).
BARATOUX, L., SÖDERLUND, U., ERNST, R.E., DE ROEVER, E., JESSELL M.W., KAMO, S., NABA, S., PERROUTY, S., METELKA, V., YATTE, D., GRENHOLM, M., DIALLO, D.P., NDIAYE, P.M., DIOH, E., COURNÈDE, C., BENOIT, M., BARATOUX, D., YOUBI, N., ROUSSE, S. & BENDAOUD, A., 2019. New U-Pb Baddeleyite Ages of Mafic Dyke Swarms of the West African and Amazonian Cratons: Implication for Their Configuration in Supercontinents Through Time. In: Srivastava R., Ernst R., Peng P. (eds) Dyke Swarms of the World: A Modern Perspective. Springer Geology. Springer, Singapore. pp 263-314. DE ROEVER, E.W.F., KROONENBERG, S.B., DELOR, C. & PHILLIPS, D., 2003. The Käyser dolerite, a Mesoproterozoic alkaline dyke suite from Suriname. Geologie de la France 2-3-4 pp 161-174