Magnetic Polarity Stratigraphy of the Pleistocene Section at Portland (Victoria), Australia

Autor: Thomas H. V. Rich, Bruce J. MacFadden, Michael J. Whitelaw, Phil McFadden
Rok vydání: 1987
Předmět:
Zdroj: Quaternary Research. 28:364-373
ISSN: 1096-0287
0033-5894
DOI: 10.1016/0033-5894(87)90004-4
Popis: Three to seven oriented paleomagnetic samples were collected from 16 sites in the Nelson Bay and Bridgewater formations at Portland, Victoria, which contains the recently discovered Nelson Bay local fauna (L.F.). The entire section has reversed polarity. These results, along withGloborotalia truncatulinoideswithin the section, and the presence of underlying middle Pliocene-dated basalts, indicate that the Portland section, and the included Nelson Bay L.F., was deposited within the late Matuyama Chron between 1.66 and 0.73 myr ago. This represents the first well-documented pre-14C Pleistocene mammalian fauna in Australia calibrated in direct stratigraphic context with absolute dating methods. In addition, the reversed polarity for the Bridgewater Formation confirms the previous hypothesis that the depositional history of this beach-sand deposit is time-transgressive across the Brunhes-Matuyama boundary.
Databáze: OpenAIRE