TY - JOUR
T1 - (U-Th)/He dating of supergene iron (oxyhydr-)oxides of the Nefza-Sejnane district (Tunisia)
T2 - new insights into mineralization and mammalian biostratigraphy
AU - YANS, Johan
AU - Verhaert, Michele
AU - Gautheron, Cécile
AU - Antoine, Pierre-Olivier
AU - Moussi, Béchir
AU - Dekoninck, Augustin
AU - Decrée, Sophie
AU - Chaftar, R.
AU - HATIRA, N.
AU - Dupuis, Christian
AU - Pinna-Jamme, Rosella
AU - Jamoussi, Fakher
N1 - Funding Information:
Wallonie-Bruxelles International: Projet 8-axe 2 Agence Nationale de la Recherche: RECA ANR-17-CE01-0012-01.
Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021/3/1
Y1 - 2021/3/1
N2 - The mining district of Nefza-Sejnane (Tunisia) encloses numerous ores and raw material deposits, all formed in relation with successive Fe-rich fluids of meteoric and/or hydrothermal origins. Here, for the first time in Tunisia, (U-Th)/He ages were obtained on supergene goethite from various localities/deposits of the district highlight direct dating of significant weathering episodes during late Tortonian and late Pleistocene. These weathering events are most likely associated with favorable conditions that combine (i) wet climate displaying sufficient meteoric water/fluid; and (ii) regional exhumation, due to large-scale vertical lithospheric movements enhancing the percolation of fluids. Matched with previous works, these results refine the stratigraphic frame for the polymetallic mineralization and clay deposits in the district, confirming the influence of meteoric fluids circulation during the late Cenozoic. As a consequence of the new (U-Th)/He data, we moreover propose a taxonomic and stratigraphic revision of the well-known mammalian fauna from the Fe-rich Douahria locality, suggesting an early Tortonian age for the fossils, i.e., prior to the first episode of meteoric event in the area.
AB - The mining district of Nefza-Sejnane (Tunisia) encloses numerous ores and raw material deposits, all formed in relation with successive Fe-rich fluids of meteoric and/or hydrothermal origins. Here, for the first time in Tunisia, (U-Th)/He ages were obtained on supergene goethite from various localities/deposits of the district highlight direct dating of significant weathering episodes during late Tortonian and late Pleistocene. These weathering events are most likely associated with favorable conditions that combine (i) wet climate displaying sufficient meteoric water/fluid; and (ii) regional exhumation, due to large-scale vertical lithospheric movements enhancing the percolation of fluids. Matched with previous works, these results refine the stratigraphic frame for the polymetallic mineralization and clay deposits in the district, confirming the influence of meteoric fluids circulation during the late Cenozoic. As a consequence of the new (U-Th)/He data, we moreover propose a taxonomic and stratigraphic revision of the well-known mammalian fauna from the Fe-rich Douahria locality, suggesting an early Tortonian age for the fossils, i.e., prior to the first episode of meteoric event in the area.
KW - (U-Th)/He
KW - Douahria mammalian fauna
KW - Goethite
KW - Supergene
KW - Tunisia
UR - http://www.scopus.com/inward/record.url?scp=85101842416&partnerID=8YFLogxK
U2 - 10.3390/min11030260
DO - 10.3390/min11030260
M3 - Article
SN - 2075-163X
VL - 11
SP - 1
EP - 19
JO - Minerals
JF - Minerals
IS - 3
M1 - 260
ER -