Premium
Ordovician and Silurian graptolite assemblages from Cerro del Fuerte, San Juan Province, Argentina
Author(s) -
Rickards Barrie,
Brussa Edsel,
Toro Blanco,
Ortega Gladys
Publication year - 1996
Publication title -
geological journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.721
H-Index - 54
eISSN - 1099-1034
pISSN - 0072-1050
DOI - 10.1002/(sici)1099-1034(199606)31:2<101::aid-gj693>3.0.co;2-v
Subject(s) - ordovician , unconformity , paleontology , geology , devonian , transect , biostratigraphy , carboniferous , paleozoic , stratigraphic section , fauna , sedimentary rock , structural basin , oceanography , ecology , biology
A description is given of three transects through the Silurian strata of Cerro del Fuerte, San Juan Province, Argentina. All are in the Precordillera structural belt; the Silurian strata probably have conformable boundaries with the Ordovician and Devonian, and there is a regional angular unconformity at the base of the Carboniferous. The Silurian includes two formations, the La Chilca below and the Los Espejos above. Both formations exhibit a coarsening upwards sequence: the Los Espejos Formation spans the Wenlock, Ludlow and, probably, Přídolí epochs, the first being of relatively fine sediments and the latter two of coarser sediments. The third transect also includes Devonian sediments which seem to represent, albeit incompletely, a third coarsening upwards cycle. The graptolite faunas have been extensively collected and form the basis of the systematic section of the paper. Late Ordovician, Llandovery and Ludlow faunas are described.