The provenance of sediments in the Barrême thrust-top basin, Haute-Provence, France
| Autor: | Maria A. Mange-Rajetzky, Martin J. Evans |
|---|---|
| Rok vydání: | 1991 |
| Předmět: | |
| Zdroj: | Geological Society, London, Special Publications. 57:323-342 |
| ISSN: | 2041-4927 0305-8719 |
| DOI: | 10.1144/gsl.sp.1991.057.01.24 |
| Popis: | This paper records the results of an integrated analysis of heavy minerals, sedimentary facies, palaeocurrents and structural data. The objective of the study was to evaluate the provenance of the sediments of the Barreme thrust-top basin. This basin contains a Late Eocene to Late Oligocene succession of shallow marine, alluvial and lacustrine sediments. Late Eocene marine transgression resulted in starvation of clastic supply to the basin hence the Calcaires Nummulitiques received only a limited influx of heavy minerals derived from local sedimentary sources, augmented by the first appearance of assemblages with andesitic affinities at c. 42–41 Ma. Clastic members associated with the overlying Marnes Bleues record a significant diversification of provenance and sediment transport paths. Clastic detritus supplied to the shallow marine Gres de Ville were derived from Permo-Triassic sediments to the south. Conglomeratic submarine channels of the La Poste member mark the introduction of Alpine ophiolite-blueschist-derived minerals at c. 37–35 Ma, eroded from the Embrun-Ubaya thrust complex to the NE. The deltaic St Lions member is dominated by volcaniclastic assemblages. Completing the marine fill, the shoreface Gres de Senez received detritus from the southerly Maures-Esterel crystalline massif. The succeeding Oligocene continental sediments record an increasing supply of minerals from Alpine lithologies. The alluvial Molasse Rouge contains reworked sedimentary detritus, including material cannibalized from the underlying marine Tertiary, and first-cycle Alpine minerals. The succeeding lacustrine Serie Saumon-Serie Grise show the increasing diversity of Alpine suites. The youngest sediments, the fluvial Gres Verts, signal a major influx of Alpine-derived assemblages related to reactivation of the Embrun-Ubaye thrusts between c. 28–27 and 25–24 Ma. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|