|
Department of Geology, University of Western Ontario, London N6A 5B7, Canada
Amoco Europe Inc., 1 Stephen Street, Tottenham Court Road, London W1P 2AU, U.K.
Lower Ordovician graptolites of the Canadian Cordillera (southeastern British Columbia to northern Yukon) are strongly allied to those of the Victorian sequences of Australia and the nearly identical succession of New Zealand, consequently the Stage classification of Victoria is adopted with only minor modifications. Biostratigraphic zones recognized herein, and their Victorian correlatives, are Tetragraptus approximatus (upper Lancefieldian), T. fruticosus (Bendigonian), Didymograptus protobifidus (Chewtonian), Isograptus victoriae lunatus (very poorly known) and I. v. maximodivergens (lower and upper Castlemanian, respectively), Oncograptus possibly with lower and upper divisions (Yapeenian), Paraglossograptus tentaculatus divisible into a lower unit equivalent to Dariwillian 1 and 2, and an upper unit correlative with about Dariwillian 3 and characterized by the appearance of Sinograptus, and Diplograptus decoratus Dariwillian 4 and higher).
Zone by zone diversity studies of Pacific Faunal Province graptolites indicate maximum species’ diversity in the fruticosus and tentaculatus zones and lowest diversity about the lunatus Zone.
This article has been cited by other articles:
 |
|
 |
|
  W. B. N. Berry and P. Wilde Graptolite biogeography: implications for palaeogeography and palaeoceanography Geological Society, London, Memoirs, 1990; 12: 129 - 137. [Abstract] [PDF]
|
|
