Mauro Papini

A one-million-year-old Homo cranium from the Danakil (Afar) Depression of Eritrea

One of the most contentious topics in the study of human evolution is that of the time, place and mode of origin of Homo sapiens. The discovery in the Northern Danakil (Afar) Depression, Eritrea, of a well-preserved Homo cranium with a mixture of characters typical of H. erectus and H. sapiens contributes significantly to this debate. The cranium was found in a succession of fluvio-deltaic and lacustrine deposits and is associated with a rich mammalian fauna of early to early-middle Pleistocene age. A magnetostratigraphic survey indicates two reversed and two normal magnetozones. The layer in which the cranium was found is near the top of the lower normal magnetozone, which is identified as the Jaramillo subchron. Consequently, the human remains can be dated at ∼1 million years before present.

The Plio-Pleistocene fluvio-lacustrine Upper Valdarno Basin (central Italy): Stratigraphy and basin fill evolution

The Upper Valdarno Basin stands out from the Neogene-Quaternary basins of the Northern Apennines given its outstanding fossil mammal record, good quality of natural and artificial outcrops and remarkable chronological control on the basin-fill succession. The present paper aims to summarize the stratigraphic and sedimentological studies focused on the Upper Valdarno Basin during the past decades, and integrate them with recent investigations. The Upper Valdarno Basin is located about 35 km SE of Florence between the Chianti Mountains and the Pratomagno Ridge. It consists of a main asymmetric tectonic depression filled with 550 m of Plio-Pleistocene fluvio-lacustrine deposits (Upper Valdarno Basin s.s.) and a minor basin known as the Palazzolo sub-basin. The Upper Valdarno Basinfill is made of three unconformity-bounded units, named Castelnuovo dei Sabbioni (CSB), Montevarchi (VRC), Torrente Ciuffenna (UFF) synthems, whereas the Palazzolo sub-basin fill consists of the Fosso Salceto (OLC) and Torrente Ciuffenna (UFF) synthems. The Upper Valdarno Basin formed during Late Pliocene because of the tectonic damming of a northeastward flowing drainage. The early phase of basin development is recorded by the accumulation of fluvial gravels in vallive settings, whereas the definitive of these streams damming caused the development of lacustrine conditions at about 3.1 Ma. The accumulation of deltaic sand fed from the SW margin caused the lake filling and stopped the deposition of the CSB Synthem.Before 2.58 Ma, a tectonic phase caused uplift of the basin and partial erosion of the CSB deposits. Deposition of the lower part of the VRC Synthem occurred during a marked basin broadening and accumulation of alluvial fan successions, which were capped by aeolian-reworked alluvial sand deposited at about 2.5 Ma. At about 2.3 Ma, a new deformative phase caused further basin widening, erosion along the SW margin and development of a small lake inthe central areas. Deposition of the upper part of the Montevarchi Synthem started just after this tectonic phase and was characterized by development of axial fluvial drainage and marginal alluvial fans.During the Early Pleistocene (Olduvai Subchron, 1.95-1.78 Ma) a subsidence pulse promoted development of floodplain lakes and swamps in the axial part of the basin, where thick organic-rich mud were accumulated. During late Early Pleistocene the capture of the paleo-Arno River, which started to flow into the basin, caused the development of a marked unconformity. This unconformity was covered by fluvial and alluvial fan deposit in the axial part and along the margin respectively.

GEOLOGY OF THE HOMO -BEARING PLEISTOCENE DANDIERO BASIN (BUIA REGION, ERITREAN DANAKIL DEPRESSION)

This paper deals with the geological context of the northernmost site in the East Africa Rift system which has yielded Homo erectus -like remains. They are dated ca. 1 Ma and have been found in the deltaic deposits of the Alat Formation belonging to the Dandiero group. This newly defined group crops out extensively in an elongated belt from the Gulf of Zula to the North to the Garsat area to the south. In the Buia-Dandiero area it ranges in age from the Early to the Middle Pleistocene, and incorporates six formations, from bottom up: the fluvial Bukra Sand and Gravel, the deltaic and lacustrine Alat Formation, fluvial Wara Sand and Gravel, the lacustrine Goreya Formation, the fluvio-deltaic Aro Sand and alluvial Addai Fanglomerate. This succession is bounded by two major unconformities, which separate it from the Neoproterozoic basement and from the overlaying Boulder Beds fanglomerate, and has been designated the Maebele Synthem. The latter is the result of two lacustrine transgression and regressions evidenced by two depositional sequences. The unconformities bounding the Maebele Synthem are related to the tectonic history of the basin fill and its substrate. The development of the two sequences was, instead, mainly controlled by lake level fluctuations and, hence, by climatic variations connected with the weakening and strengthening of the monsoons in the northwestern Indian ocean. The environment where the Buia Homo lived was a savannah with some scattered water pools. This environment probably extended farther north along the western coastal plain of the Red Sea, and was a preferential pathway for the dispersal of the hominids from East Africa toward Eurasia.

Lithostratigraphy, sedimentology and facies architecture of the Late Cretaceous succession in the central Mahajanga Basin, Madagascar

Abstract New stratigraphical and sedimentological data are presented on the Late Cretaceous succession exposed in the central Mahajanga Basin (And ranolava-Berivotra area), western Madagascar. Eight lithostratigraphical units, Santonian to Maastrichtian in age, have been mapped in this area. These have been recognised on the basis of lithologies, sedimentary structures and fossil content. Particular attention was paid to the recognition of the surfaces separating these units, such as erosive, non-depositional and transgressive surfaces. The stratigraphical arrangement of these units can be placed tentatively in a sequence stratigraphical model and these units can be interpreted as elements of at least four depositional sequences. The comparison between this sedimentary succession and the latest Cretaceous volcano-sedimentary history of the other western Madagascar basins (Morondava and Diego-Suarez Basins) shows several analogies. The most striking are: north to south migration of basaltic volcanism and associated continental/transitional conditions; and definitive marine flooding of the western margin of Madagascar since the Maastrichtian. These features are thought to be related to the regional geodynamic events associated with the break-up of the Madagascar-India block. It is likely that uplift/subsidence pulses, more than sea-level variations, controlled the latest Cretaceous depositional patterns in the central Mahajanga Basin.

Stratigraphic context and paleoenvironmental significance of minor taxa (Pisces, Reptilia, Aves, Rodentia) from the late Early Pleistocene paleoanthropological site of Buia (Eritrea)

The Buia Homo site, also known as Wadi Aalad, is an East African paleoanthropological site near the village of Buia that, due to its very rich yield from the late Early Pleistocene, has been intensively investigated since 1994. In this paper, which reports on the finds of the 2010-2011 excavations, we include new fossil evidence on previously identified taxa (i.e., reptiles), as well as the very first description of the small mammal, fish and bird remains discovered. In particular, this study documents the discovery of the first African fossil of the genus Burhinus (Aves, Charadriiformes) and of the first rodent from the site. This latter is identified as a thryonomyid rodent (cane rat), a relatively common taxon in African paleoanthropological faunal assemblages. On the whole, the new occurrences documented within the Buia vertebrate assemblage confirm the occurrence of taxa characterized by strong water dependence. The paleoenvironmental characteristics of the fauna are confirmed as fully compatible with the evidence obtained through sedimentology and facies analysis, documenting the sedimentary evolution of fluvio-deltaic and lacustrine systems.

Stratigraphic context and taxonomic assessment of the large cercopithecoid (Primates, Mammalia) from the late Early Pleistocene palaeoanthropological site of Buia (Eritrea)

IntroductionThe Buia-Dandero area (100 km south of Massawa, northernDanakil Depression, Eritrea; Fig. 1A) is well known for the 1-million-year-old Homo cranium from Buia (Abbate et al., 1998;Macchiarelli et al., 2004; Bondioli et al., 2006). The Early-to-Middle Pleistocene stratigraphic series of the Dandero basin,located near the Buia village, presents about 1 km of continentaldeposits. Since its discovery in 1994, this area has been the subjectof research by an international team coordinated by the EarthSciences Department of the University of Florence and the EritreaNational Museum. The investigated area yielded hominin remains(Abbate et al., 1998, 2004a; Rook et al., 2002), abundant fossilvertebrates (Ferretti et al., 2003; Delfino et al., 2004; Martinez-Navarro et al., 2004, 2010), and a rich archaeological record ofMode 1 (Oldowan) and Mode 2 (Acheulean) tool industries in a lateEarly Pleistocene chronological framework (Abbate et al., 2004a).The age of the Homo-bearing sediments (Alat Formation) of theBuia sedimentary succession, established by different investigativeapproaches, falls within the Jaramillo Subchron (C1r.1n), close to1.0Ma(Albianelli and Napoleone, 2004; Bigazzi et al., 2004).In addition to the hominin remains, non-human primates aresolely represented in the Buia faunal assemblage (Alat Formation)by a large cercopithecoid cranial fragment, tentatively listed in theBuia mammal fauna (Martinez-Navarro et al., 2004)asTher-opithecus cf. Theropithecus oswaldi. The genus Theropithecus is verycommon in the Plio-Pleistocene of Africa, occurring at sites inNorth, East and South Africa, within a time span ranging from3.4Mato0.5Ma(Delsonetal.,1993).Weprovidehereadescriptionof the specimen (UA-463), which is housed in the Paleontologicalcollections of the National Museum of Eritrea (Asmara).The mammalian assemblage from BuiaAbbateetal.(1998)publishedapreliminaryvertebratefaunallistfrom Buia. Successive field collections and taxonomic descriptionsallowed updating the Buia vertebrate faunal assemblage, whichrepresentsatypicaleasternAfricanlateEarlyPleistocenefauna.Buiais characterised by the occurrence of evolved last-representativeforms of Elephas recki, Hippopotamus gorgops, Kolpochoerus old-uvaiensis, Kolpochoerus majus, Metridiochoerus aff. M. modestus andBos buiaensis, associated with taxa that persist in the present day,such as Ceratotherium simum, Equus cf. E. grevyi, Tragelaphus cf.Theropithecus spekei, and Kobus cf. K. ellipsiprymnus. The geologicaland sedimentological framework, as well as paleomagnetism andfissiontrackdating(Abbateetal.,2004a;Ghinassietal.,2009)areingood agreement with the mammal biochronology data, attesting toa latest Early Pleistocene age (Martinez-Navarro et al., 2004, 2010).Thisvertebrateassemblageispredominantlycomposedoftaxawithstrong water dependence like hippos, waterbuck, sitatunga, Kolpo-choerus, crocodiles, paleomedusid chelonians and African rock

Facies associations of the northern Dandiero Basin (Danakil depression, Eritrea, including the Pleistocene Buya homo site)

The Dandiero Basin is located on the northern part of the 300 km-long Danakil depression. The geologic succession filling the Dandiero Basin is up to 1000 m thick and consists of three synthems, inascending order: the Early-to-Middle Pleistocene Maebele Synthem of fluvio-lacustrine origin; the Late Pleistocene Curbelu Synthem of alluvial deposits and the Late Pleistocene to Holocene Samoti Synthem alluvio-eolian sand. This study and map (1:5000 scale) focuses on the Maebele Synthem exposed in a 3.8 km2 area near Mt. Alat. Regionally, the Maebele Synthem consists of six lithostratigraphic units, in ascending order: (1) the Bukra Sand and Gravel, (2) the Alat Formation, (3) the Wara Sand and Gravel, (4) the Goreya Formation, and (5) Aro Sand, (6) Addai Fanglomerate. The Bukra Sand and Gravel is about 150–200 m thick and made up mainly of fluvial sand. The Alat Formation is 70–100 m thick and consists of alternating fluvial, lacustrine and deltaic deposits. Fluvial deposits consist of sand-filled channels that occur as amalgamated or isolated bodies within floodplain mud. Lacustrine sediments consist of mud, whereas deltaic deposits are represented by sandy shallow-water and Gilbert-type deltas. The Wara Sand and Gravel (250 m thick) is made up of fluvial sand. The Goreya Formation (50 m thick) consists of lacustrine, deltaic and fluvial deposits. The fluvial deposits consist of sand-filled channels the lacustrine sediments consist of mud with subordinate limestone, and the deltaic deposits are represented by sandy shallow-water deltas. The Aro Sand consists of fluvial sand up to 120 m thick. The Addai Fanglomerate (250–300 m thick) consists of coarse-grained alluvial fan.

Messinian-earliest Zanclean tectonic-depositional dynamics of the Cinigiano-Baccinello and Velona basins (Tuscany, Italy)

The paper reports a revision of the tectonic-depositional evolution of the continental Cinigiano-Baccinello and Velona basins, located in the Amiata Volcano region, with special emphasis on the Messinian dynamics. Integration of facies analysis, magnetostratigraphy, and structural geology allowed a comparison of the evolution of these basins and a discussion of possible local to regional implications. At a local scale, crustal shortening, accommodated by thrust faults and related anticlines delimiting the basins, determined a dynamic physiographic and hydrographic scenario during the Messinian. Uplift of the tectonically-controlled shoulders was paired with pulses of subsidence in the basins that favoured the development of palustrine-lacustrine settings or endorheic alluvial plains. Stages of quiescent tectonics favoured fluvial incision of structural thresholds and the development of a south-directed drainage system, particularly developed during the late Messinian in coincidence with the Mediterranean Messinian Salinity Crisis. The dominant fluvial and clastic depositional pattern recorded in these basins during such a regional scale event points to local tectonic activity of the Northern Apennines playing a major role than the climatic, eustatic and geodynamic factors that controlled the Mediterranean region.

FOSSO DELLA FITTAIA: THE OLDEST TUSCO-SARDINIAN LATE MIOCENE ENDEMIC VERTEBRATE ASSEMBLAGES (BACCINELLO-CINIGIANO BASIN, TUSCANY, ITALY)

The late Miocene continental successions of the Baccinello-Cinigiano basin (Grosseto), one of the longest and most continuous vertebrate-bearing continental successions in the Neogene Italian record, yielded at least four superimposed vertebrate assemblages bracketed in the time span 8.3 - 6.4 Ma. The Baccinello-Cinigiano basin is famous for recording endemic vertebrate assemblages that include the youngest European Miocene hominoid, Oreopithecus bambolii . The late Miocene endemic vertebrate fauna known as the Baccinello V0 assemblage is the oldest vertebrate fauna within the Baccinello-Cinigiano basin succession, being correlated to the European mammal Neogene unit MN11. Recent field surveys along the Trasubbie river allowed studying in detail the basal Baccinello-Cinigiano sedimentary succession, and sampling fossiliferous level bearing microvertebrates along the small creek Fosso della Fittaia. The sample “Fosso della Fittaia 2013” yielded about 170 fossil remains improving our documentation of the oldest vertebrate assemblages from the Baccinello-Cinigian basin. As far as rodents are concerned, in addition to the already recognized murid Huerzelerimys and glirid Anthracoglis , a few dental remains are assigned to a new genus and species of giant dormouse. It is further worth noting the occurrence in the sample of shrew remains (the first described from the Baccinello-Cinigiano basin) identified as cf. Lartetium . The latter attests the presence of a crocidosoricine in the Fosso della Fittaia 2013 assemblage, postdating the youngest known occurrences of the subfamily by at least 1 my. The vertebrate assemblage is completed by a diverse herpetofauna and the first fish remains reported from the basin.

Stratigraphic Analysis of Upper Cretaceous Rocks in the Mahajanga Basin, Northwestern Madagascar: Implications for Ancient and Modern Faunas: A Discussion

Rogers et al. (2000) presented new stratigraphic data on Upper Cretaceous sedimentary successions in the central Mahajanga Basin, northwest Madagascar, the results of field studies by the Mahajanga Basin Project team during the 1990s (Krause et al. 1999). The authors focused on identifying and collecting Late Cretaceous fossils (Rogers et al. 2000, and references therein) and attempted to update the rock and time stratigraphy of part of the Mahajanga Basin. In this discussion, we wish to demonstrate that Rogers et al. (2000) provided, first, an incorrect lithostratigraphic picture, second, a nonrealistic account of the stratigraphic and depositional evolution of the succession, and third, only a partial reassessment of the chronostratigraphy of the basin’s Upper Cretaceous deposits.