Carnevale, Giorgio

Delfino, Massimo

Donato, P.

Ghinassi, M.

Mercatante, G.

Oms, O.

Papini, M.

Pavia, Marco

Rook, L.

Sani, F.

Scarciglia, F.

English

Institutional Research Information System University of Turin

Geophysical Research AbstractsVol. 17, EGU2015-12518, 2015EGU General Assembly 2015© Author(s) 2015. CC Attribution 3.0 License.Pleistocene soil development and paleoenvironmental dynamics in EastAfrica: a multidisciplinary study of the Homo-bearing Aalat succession,Dandiero BasinFabio Scarciglia (1), Giuseppe Mercatante (1), Paola Donato (1), Massimiliano Ghinassi (2), Giorgio Carnevale(3), Massimo Delfino (3), Oriol Oms (4), Mauro Papini (5), Marco Pavia (3), Federico Sani (5), and LorenzoRook (5)(1) Dipartimento di Biologia, Ecologia e Scienze della Terra (DiBEST), Università della Calabria, Arcavacata di Rende (CS),Italy (fabio.scarciglia@unical.it, giuseppe.mercatante114602@yahoo.it, paola.donato@unical.it), (2) Dipartimento diGeoscienze, Università di Padova, Padova, Italy (massimiliano.ghinassi@unipd.it), (3) Dipartimento di Scienze della Terra,Università degli Studi di Torino, Torino, Italy (giorgio.carnevale@unito.it, tulse.luper@gmail.com, marco.pavia@unito.it), (4)Departamento de Geologia, Universitat Autònoma de Barcelona, Bellaterra, Spain (JosepOriol.Oms@uab.cat), (5)Dipartimento di Scienze della Terra, Università di Firenze, Firenze, Italy (mauro.papini@geo.unifi.it, fsani@geo.unifi.it,lorenzo.rook@unifi.it)Pleistocene environmental changes in East Africa, largely documented by deep marine or lacustrine records corre-lated with inland high-resolution, Homo-bearing stratigraphic successions, have been so far interpreted as a majorcause of faunal dispersal and human evolution. However, only few studies focused on reconstruction of paleoenvi-ronmental dynamics from continental successions, given the usually poor continuity and extension of stratigraphicrecords. In this work we report on a multidisciplinary study of the Early to Middle Pleistocene sedimentary fillof the Dandiero Basin (Eritrean Danakil), a morpho-tectonic depression in the East African Rift System, whichrepresents the only continental stratigraphy including human remains of Homo erectus/ergaster and abundant fossilvertebrates in the northernmost sector of this region. Sedimentological, pedological, volcanological and paleon-tological investigations were performed on the Aalat section, located in the northern part of the Dandiero Basin,as tools for an integrated reconstruction of the Early-Middle Pleistocene transition in East Africa. This section isalmost 300 m thick and records repeated shifts from fluvial to deltaic and lacustrine depositional environments,as a response to local tectonic activity and climate changes. Sedimentary facies distribution and paleocurrent datashow that sedimentation was controlled by a NS-trending axial drainage. Some tephra layers were identified bothat the bottom and the top of the section, whereas two main fossiliferous layers were detected in its lower part.Terrestrial vertebrate faunas include a typical Early to Middle Pleistocene East African mammalian assemblage,where taxa characterized by strong water dependence prevail. Also the ichthyofauna is consistent with the shallowwater fluvio-lacustrine paleobiotopes. High-quality paleomagnetic analyses, integrated with radiometric dating andvertebrate paleontology, allowed to substantiate the chronological constraints of the Aalat section to a time spanapproximately bracketed between the Jaramillo event (ca. 1.07-0.99 Ma) and the Matuyama–Brunhes magneticfield reversal (ca. 0.78 Ma). High rates of sedimentary aggradation can be estimated around 1 mm/a, coherentlywith a poor to moderate degree of soil development and evidence of soil truncation by erosion. Physico-chemical,mineralogical, geochemical and micromorphological analyses were carried out on selected soil samples. Weather-ing and pedogenetic features mainly consist of pedogenic structure, secondary carbonate accumulations (followingcarbonate leaching) and iron-oxide/hydroxide segregations, promoted by water infiltration under varying drainageconditions and/or seasonal contrast. The complex patterns of some petrocalcic horizons and rare rubified soils tes-tify for occasionally longer geomorphic stability and non-deposition, which were more prone to pedogenesis.Our multidisciplinary study revealed that the Aalat section in the Dandiero Basin represents a promising conti-nental archive of the main paleoenvironmental changes occurred during the Early-Middle Pleistocene transition inEast Africa.

Pleistocene soil development and paleoenvironmental dynamics in East Africa: a multidisciplinary study of the Homo-bearing Aalat succession, Dandiero Basin

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Pleistocene soil development and paleoenvironmental dynamics in East Africa: a multidisciplinary study of the Homo-bearing Aalat succession, Dandiero Basin

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