- Tytuł:
- Stratigraphy, palynology and organic geochemistry of the Devonian-Mississippian metasedimentary Albergaria-a-Velha Unit (Porto-Tomar shear zone, W Portugal)
- Autorzy:
-
Machado, G.
Francu, E.
Vavrdová, M.
Flores, D.
Fonseca, P. E.
Rocha, F. T.
Pereira, L. C. G.
Gomes, A.
Fonseca, M.
Chaminé, H. - Powiązania:
- https://bibliotekanauki.pl/articles/2059150.pdf
- Data publikacji:
- 2011
- Wydawca:
- Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
- Tematy:
-
Mississippian
Late Devonian
Ossa-Morena Zone
Porto-Tomar shear zone
palynology
organic geochemistry - Opis:
- The Albergaria-a-Velha Unit is one of several tectonostratigraphic out-of-sequence units of the metamorphic belt associated with the Porto-Tomar shear zone (Ossa-Morena Zone, W Portugal). It is composed of considerably deformed - very low grade - metasediments, namely shales, siltstones and rare fine sandstones. In this work we present new sedimentological and biostratigraphical data that suggest the Albergaria-a-Velha Unit was deposited from the (?)early Frasnian to the Serpukhovian in a distal marine environment, where turbiditic and basinal sedimentation prevailed. Palynofacies analysis and lithological data point to a gradual increase of terrestrial input, suggesting a prograding system. Detrital framework data is indicative of a stable cratonic sediment source area composed of low grade metamorphic rocks. The timing of the onset of the Porto-Tomar shear zone activity and consequently its influence on the sedimentation of this unit is discussed. Organic petrology and geochemistry data indicate that the Albergaria-a-Velha Unit is within the dry gas window in terms of hydrocarbon generation ranges.
- Źródło:
-
Geological Quarterly; 2011, 55, 2; 139-164
1641-7291 - Pojawia się w:
- Geological Quarterly
- Dostawca treści:
- Biblioteka Nauki