Caracciolo L, Andò S, Vermeesch P, Garzanti E, McCabe R, Barbarano M, Paleari C, Rittner M, Pearce T (2019)
Publication Language: English
Publication Type: Journal article, Original article
Publication year: 2019
Edited Volumes: Application of Analytical Techniques to Petroleum Systems
Book Volume: SP484
Journal Issue: Application of Analytical Techniques to Petroleum Systems
This paper shows how heavy minerals and single-grain varietal studies can be conducted on silt (representing ~ 50% of world’s sediments) sediments to obtain quantitative data as efficiently as for sand-sized sediments. The analytical workflows include heavy mineral separation using a wide grain-size window (15-355 μ) analysed through integrated optical analysis, RAMAN spectroscopy, QEMSCAN microscopy, U-Pb dating of detrital zircon. Upper Jurassic-Cretaceous silt-sized sediments from the Mandawa basin of central-southern Tanzania have been selected for the scope of this research. Raman-aided heavy mineral analysis reveals garnet and apatite to be the most common minerals together with durable zircon, tourmaline and subordinate rutile. Accessory but diagnostic phases are titanite, staurolite, epidote, and monazite. Etch pits on garnet and cockscomb features on staurolite document the significant effect of diagenesis on the pristine heavy mineral assemblage. Multivariate statistical analysis highlights a close association among durable minerals (zircon, tourmaline and rutile, ZTR) while garnet and apatite plot alone reflecting independence between the three group of variables with garnet increasing in Jurassic samples. Raman data for garnet end-member analysis document different associations between Jurassic (richer in A, Bi and Bii types) and Cretaceous (dominant A, Ci and Cii types) samples. U-Pb dating of detrital zircon and their statistical integration with the above mentioned datasets provide further insights on changes in provenance and/or drainage systems. Metamorphic rocks of the early and late Pan-African orogeny terranes of the Mozambique belt and those of the Irumide Belt acted as main source of sediment during the Jurassic. Cretaceous sediments record a broadening of the drainage system reaching as far as the Usagran-Ubendian Belt and the Tanzanian Archean Craton.
Caracciolo, L., Andò, S., Vermeesch, P., Garzanti, E., McCabe, R., Barbarano, M.,... Pearce, T. (2019). A multidisciplinary approach for the quantitative provenance analysis of siltstone. Mesozoic Mandawa Basin, southeastern Tanzania. Journal of the Geological Society, SP484(Application of Analytical Techniques to Petroleum Systems). https://dx.doi.org/10.1144/SP484-2018-136
Caracciolo, Luca, et al. "A multidisciplinary approach for the quantitative provenance analysis of siltstone. Mesozoic Mandawa Basin, southeastern Tanzania." Journal of the Geological Society SP484.Application of Analytical Techniques to Petroleum Systems (2019).