Distribution of acid-resistant microfossils in the northern East Baltic Ashgillian
1984) attributed an Ashgillian
or younger age to this series because of the absence of acidic volcanic rocks interbedded in the series.
The lithological variation, a great number of lithostratigraphical units and uneven palaeontological data have complicated the correlation and compilation of models of basin development during the middle Ashgillian
This unconformity corresponds to the eustatic fall in sea level associated with the terminal Ashgillian
event (Berry and Boucot, 1973).
As regards the Upper Ordovician exposed in southern Normandy, based on conodonts and other fossils, the Vaux Limestone as well as limestone olistoliths in the overlying 'Tillite de Feugueroles' ('Pelites a fragments') were dated as Ashgillian
(Weyant et al.
39-41) from the Rawtheyan (beds 5a), Oslo Region, Norway; the North American species Grewingkia callahanensis Elias, 1984 from the Ashgillian
, eastern Klamath Mountains, California; Grewingkia penobscotensis Elias, 1982 from the Ashgillian
, County of Maine.
The first tract contains the oldest part of the Late Ordovician-Devonian sequence and comprises Ashgillian
to possibly Llandoverian volcanic, clastic sedimentary and carbonate rocks (the Goss Point and Simpsons Island formations as defined by McLeod (1995)).
Caradocian and Ashgillian
Chitinozoa from the subsurface of Gotland.
1, described by Potter (1990b) from the Ashgillian
in northern California, USA.
A westward extension of the upper Ashgillian
Brachiopods from the Jerrestad Mudstone (Early Ashgillian
, Ordovician) from a Boring in Southern Sweden.
graptolite fauna of the Yangtze region and the biogeographical distribution of diversity in the latest Ordovician.