If these rocks are of Upper Devonian age
, as we propose in this study, the Guaraco Norte Formation would be a preorogenic succession related to the Chanic cycle and separated from the Gondwanan succession by a major unconformity (Fig.
The Sierra Grande Formation, a quartzose clastic shallow water succession, contains a poorly preserved Malvinokaffric fauna of brachiopods and trilobites of lower Silurian to Lower Devonian age (Mancenido and Damborenea, 1984; Limarino et al., 1999).
These authors assigned a probable Devonian age to these rocks, criteria previously proposed by Darwin (1846), who correlated these rocks with the Devonian quartzites of the Malvinas Island.
Metasedimentary deposits of Devonian age bearing Malvinokaffric fauna were described in the accretionary prism of Chile at 42[degrees]24'S latitude.
McLeod (1990) pointed out that the latter age contradicts fossil evidence, which indicates an Early Devonian age
for the Eastport Formation in the contact aureole of the granite.
The Early Devonian age
was proposed for the Rezekne RS, using fish faunas in the interregional correlation, among others those from the Eifel Hills sequence (Mark-Kurik 1991, fig.
Based on the close resemblance of the Eastport forms to the Devonian age European material, both paleontologists felt justified in assigning an Early Devonian age to the Maine unit (Martinsson 1970, 1977; Berdan 1971, 1990; Brookins etal.
The remaining faunal elements within the Eastport Formation are all known to occur within Silurian and Devonian age deposits alike and are therefore not stratigraphically useful in this context.
There are some more indications of the secondary magnetizations of Early Devonian age
from the igneous rocks of Kalak Nappe Complex, northern Norway (Torsvik et al.
Ostracodes from both the Hersey and the Eastport formations of coastal Maine are indicative of an Early Devonian age
A source for the few zircon grains represented in sample 180] with Ordovician to Early Devonian ages
is not known in the Mira terrane.
A strong discharge of water from fissured and karst rocks of the Triassic and Devonian ages
present at shallow depths is caused by the nearby potable water intake.