Publication Name: The Canning Basin, W.A.
Authors: R.W. Cooper, W.D.M. Hall and G.R. Styles
Date Published: December 1984
Number of Pages: 17
Reference Type: Book Section
Abstract:A sequence of gently dipping, shallow-water limestone up to 800 m thick is exposed in the central Pillara Range and forms part of a Middle to Late Devonian carbonate platform developed on the Lennard Shelf. A lower Amphipora members rests unconformably on an irregular basement and is overlain by a lower fenestral-Actinostroma member, a cyclic Argutastrea member and an upper ActinostromaStachyodes member. An upper fenestral-Actinostroma member occurs in the northwest between the cyclic Argutastrea member and the upper ActinostromaStachyodes member. Cyclic lithological repetitions, formed during upward shoaling sedimentation, are a common feature throughout much of the stratigraphic sequence.
The lower fenestral-Actinostroma member and the lower part of the cyclic Argutastrea member pass laterally into calcareous siltstone at the platform margin, while the overyling members are overlain by or pass laterally
into steeply dipping marginal-slope limestone. Steep reef margins are developed only in the northwest, adjacent
to the upper Actinostroma-Stachyodes member. The area is cut by only very minor faults, except at its northwest end, and beds only a few metres thick can be traced over considerable distances.