TY  - JOUR
A1  - Chemam, Asma
A1  - Hadjzobir, Soraya
A1  - Daif, Menana
A1  - Altenberger, Uwe
A1  - Günter, Christina
T1  - Provenance analyses of the heavy-mineral beach sands of the Annaba coast, northeast Algeria, and their consequences for the evaluation of fossil placer deposit
JF  - Journal of earth system science
N2  - The paper presents the first study of heavy-mineral sand beaches from the Mediterranean coast of Annaba/Algeria. The studied beaches run along the basement outcrops of the Edough massif, which are mainly composed by micaschists, tourmaline-rich quartzo-feldspathic veins, gneisses, skarns and marbles. Sand samples were taken from three localities (Ain Achir, Plage-Militaire and El Nasr). The heavy-mineral fraction comprises between 74 and 91 vol%. The garnets of the beaches are almandine rich and tourmalines vary with respect to their location from schorl to dravite. Tourmaline at Ain Achir and the Plage-Militaire is schorlits, while at El Nasr beach dravite is ubiquitous. The World Shale Average normalised REE of the sands and the basement outcrops reveal: (i) Ain Achir beach: REE pattern of sand and the coastal rocks from the studied beaches reflects a multiple sources; (ii) Plage-Militaire: the sand and the coastal outcrops show similar LREE and a strong enrichment in HREE, suggesting the presence HREE-rich phases found as inclusions in staurolite; (iii) El Nasr: two types of sand patterns are found: one with flat REE pattern similar to the proximal rocks and other one enriched in HREE suggesting a mixed source.
KW  - Provenance
KW  - heavy minerals
KW  - beach sediments
KW  - fossil placer
KW  - geochemistry
KW  - Annaba
KW  - Algeria
Y1  - 2018
U6  - https://doi.org/10.1007/s12040-018-1019-z
SN  - 0253-4126
SN  - 0973-774X
VL  - 127
IS  - 8
PB  - Indian Academy of Science
CY  - Bangalore
ER  - 
TY  - JOUR
A1  - Zobir, Soraya Hadj
A1  - Altenberger, Uwe
A1  - Günter, Christina
T1  - Geochemistry and petrology of metamorphosed submarine basic ashes in the Edough Massif (Cap de Garde, Annaba, northeastern Algeria)
JF  - Comptes rendus geoscience
N2  - The study presents the first evidence of metamorphosed submarine ashes in the Edough Massif, in northeastern Algeria. It occurs below the greenschist-facies Tellian units that represent the thrusted Mesozoic to Eocene passive paleomargin of northern Africa deposited on thinned continental crust. The metamorphic complex consists of tectonically superposed units composed of gneisses (lower unit) and micaschists (upper unit). At the Cap de Garde, these units enclose an "intermediate unit" composed of micaschists and meter-thick layers of marbles, which are sometimes intercalated with amphibolites. The latter occur as discontinuous small lenses and layers. The amphibolites are parallel to the primary bedding of the marbles and the main foliation. Chemical markers and field observations indicate that they are metamorphic equivalents of basic igneous rocks. The lenticular character, low thickness and multiple intercalations with marine sediments and the unusual high lithium concentrations suggest subaqueous near-source basaltic ash-fall deposits in a marine environment. (C) 2014 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.
KW  - Amphibolites
KW  - Submarine sediments
KW  - Basaltic ash-fall deposits
KW  - Edough
KW  - Algeria
Y1  - 2014
U6  - https://doi.org/10.1016/j.crte.2014.09.002
SN  - 1631-0713
SN  - 1778-7025
VL  - 346
IS  - 9-10
SP  - 244
EP  - 254
PB  - Elsevier
CY  - Paris
ER  -