Notes on South African geology
DOI:
https://doi.org/10.21504/saqj.14.2674Keywords:
Mineralogy -- Cape Colony, Geology -- Cape Colony, Petrifactions, Marine Fossils, Vegetable Fossils, Martial-Pyrites, Shistone (Clay-Slate), Quartz (Hexagonal Quartz, Opake-Quartz), Agate, Carbonate of Lime, Prehnite, Native Saltpetre, Amianthus, Limestone, Iron-Ores, Mica, Feldspar, Stalactites, Zwart-kop River, Zondag River, Zwart Ruggens, Bruintjes Hoogte, Sneeuwbergen, Karroo, Orange River, Cango (Caverns), Cedar-Mountains, Bokkeveldts, Oliphants River, Namaqualand, Kamies Mountains, Knysna, Plettenberg's Bay, Langekloof, Uitenhage, Algoa BayAbstract
This article, a collection of geological notes by Mr Grisbrook, summarises various mineral and fossil discoveries across several regions of the Cape Colony (now South Africa).
The observations highlight the abundance of:
-
Fossils: The Zwart-kop and Zondag Rivers (Uitenhage District) are noted for their rich marine petrifactions and vegetable fossils. The Cedar-Mountains and Bokkeveldts are cited as the main source for the extensive collection of the colonial geologist, Dr Thom.
-
Minerals: Discoveries include Martial-pyrites and quartz in the Zwart Ruggens; exceptional hexagonal quartz (including fluid-filled specimens) at Bruintjes Hoogte; carbonate of lime and the "beautiful green mineral" Prehnite in the Sneeuwbergen; and agates, crystalline substances, and amianthus along the Orange River. Namaqualand is known for its iron ores, and the Kamies Mountains are renowned for their mica, quartz, and feldspar deposits.
-
Formations: The Cango Caverns and the caverns at the Knysna River entrance are noted for large crystalline carbonate of lime formations (stalactites). The paper also references the valuable limestone quarries on the Oliphants River and the geological interest of the deep ravines near George, which reveal the nature of the great primitive mountain range base.
-
Fossil Wood: The remains of a significant fossil tree near Plettenberg's Bay are mentioned, with specimens housed in the Cape Town Museum.
The notes serve as a descriptive inventory of significant mineralogical and palaeontological sites, providing valuable, though unsynthesized, geological intelligence for the region.
Downloads
