The geology of the Falkland Islands

• Main Authors: Aldiss, D.T., Edwards, E.J.
• Format: Report
• Language: English
• Published: British Geological Survey 1999
• Subjects: Antarctic; The Antarctic; Patagonia; Meredith; Antarc*
• Online Access: http://nora.nerc.ac.uk/id/eprint/507542/; https://nora.nerc.ac.uk/id/eprint/507542/1/WC99010.pdf

This report is complementary to the 1:250 000 scale geological map of the Falkland Islands compiled in 1998. The report and map are products of the Falkland Islands Geological Mapping Project (1996-1998). Geological observation and research in the Islands date from 1764. The Islands were visited during two pioneering scientific cruises in the 19th century. Subsequently, many scientists visited en route to the Antarctic or Patagonia. Geological affinities to other parts of the southern continents, especially South Africa, were noted early in the 20th century. There have been two previous attempts to create a geological map of the Islands, both motivated primarily by the search for economic mineral deposits onshore. In the last few decades much effort has been directed to understanding the Falklands’ place in Gondwana, the processes by which the Islands have moved to their present position by continental drift and the concomitant development of offshore sedimentary basins. Considerable progress in describing the superficial deposits was made in the 1970’s, and during the last ten years. The stratigraphic subdivisions of the geological sequence shown on the previous geological maps have been substantiated and defined more rigorously than before. In addition, several new stratigraphic units have been recognised. Each unit is described with an introductory summary of composition and distribution, followed by comments on nomenclature and stratigraphic relationships, associated landforms, distinguishing characters, and the criteria used to locate and survey the stratigraphic base. Detailed descriptions of composition, sedimentary structures and fossil content then lead to brief comments on the environment of deposition, age and correlation. The bedrock geological formations (‘solid geology’) can be divided into four age groups. The Proterozoic granites and amphibolite facies gneisses of the Cape Meredith Complex (about 1150 to 1000 million years old) are overlain in turn by sedimentary sequences of the ?Silurian to ...