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In this paper, we present the site of Valdeprovedo (Sierra de Atapuerca, Burgos), an open-air Paleolithic site. This site is attractive for study and research for three main reasons. First, it is an open-air site with an extraordinarily well-preserved lithic assemblage that corresponds to a very short-lived event. Second, in this small area, refits have been achieved with a high refitting rate, which allows us to reconstruct the action carried out in this place during a specific moment, around 28 ka. And third, this is the first site of this chronology that has been documented in the Sierra de Atapuerca, providing new data on the inland population of the Iberian Peninsula by Upper Paleolithic groups. [ABSTRACT FROM AUTHOR]

The Calamocha fault is an 18-km-long, NNW–SSE striking pure normal fault that moves down the northern sector of the Jiloca graben with respect to the Neogene infill of the Calatayud basin (central Iberian Chain). Its structure and kinematics are characterized by means of detailed geological mapping, morphotectonic analysis and data recording at the outcrop scale. The Calamocha fault represents the inversion of a previous contractional fault zone under the recent tensional stress field (WSW–ENE trending σ3 trajectories). The extensional activity started during the Late Pliocene (ca. 3.8 Ma), accumulating a maximum net slip of 190–230 m (long-term slip rate of 0.05–0.06 mm/a). The palaeoseismological study of three artificial exposures near Calamocha town evidenced recurrent slip during the Late Pleistocene, which proves its active character. Analysis of faulted clastic alluvial units, dated by means of optically stimulated luminescence (OSL), reveals at least eight slip events since 145.9 ± 9.1 ka, the last one being younger than 13.8 ± 0.9 ka. Only a few events represent visible accumulated displacement on the main synthetic rupture surfaces; this allows a rough estimate of the short-term slip rate (during the Late Pleistocene) of about 0.1 mm/a, faster than the long-term rate. The Calamocha fault could potentially produce a characteristic earthquake (in the sense of Schwartz and Coppersmith, J Geophys Res 89:5681–5698, 1984) with moment magnitude Mw ≈ 6.7 ± 0.3 (Mw ≈ 6.9 ± 0.3 in a scenario of activation of the whole Calamocha–Daroca fault zone), average coseismic displacement of 0.5–1.3 m and average recurrence period under 15 ka. [ABSTRACT FROM AUTHOR]

Olduvai Gorge (Tanzania) is a key site for the study of human evolution as well as the origin of modern humans and the Middle Stone Age (MSA). In this study, we present a new MSA location named Dorothy Garrod Site (DGS), found in the main branch of Olduvai Gorge. The site has only one archaeological level, located stratigraphically in the Upper Ndutu. Although it has not yet been possible to radiometrically date it, it has yielded numerous archaeological remains with a functional association between the faunal remains and the lithic industry. The fauna identified includes Alcelaphini, Hippotragini, and Equidae, some of which present percussion marks and evidence of burning. The lithic industry involved knapping using discoid methods. The retouched blanks are denticulates and retouched flakes with, up to now, a total absence of points. DGS is therefore a new site that will aid our understanding of modern human occupations in northern Tanzania in a period for which there is a dearth of properly contextualised archaeological evidence. [ABSTRACT FROM AUTHOR]

The E–W trending, nearly pure extensional Valdecebro fault zone is a transverse structure at the central sector of the N–S Teruel graben. It was activated by the Late Ruscinian (Early Pliocene, ca. 3.7 Ma), giving rise to structural rearrangement of the graben margin. Until the Late Pleistocene, it has accommodated a net slip ca. 205 m, with slip rate of 0.055 mm/a. Paleoseismicity has been analysed in a 29-m-long, 5-m-deep trench excavated through a fault branch that offsets a Pleistocene pediment surface. The paleoseismic succession includes a minimum of 6–7 events occurred since ca. 142 ka BP, although a model with 12 events could be more realistic. The following paleoseismic parameters have been inferred, assuming a minimum of 6 and a maximum of 12 events: average coseismic slip = 58–117 cm; recurrence period = 8.4–28.4 ka; potential moment magnitude Mw = 5.8–5.9. The recorded displacement since ca. 142 ka BP totalizes 7.0 m, with slip rate of 0.05–0.07 mm/a. Slip on the transverse Valdecebro fault zone has critically contributed to bulk deformation under a prevailing 'multidirectional' extensional regime. Drainage patterns have been rearranged, recurrently switching between westward and southward directions as a consequence of diverse slip episodes at the Valdecebro fault zone (E–W) and the neighbouring La Hita (N–S) and Concud (NW–SE) faults. The ultimate westward drainage of the Valdecebro depression incised and dismantled a southward-sloping Pleistocene pediment sourced at the Valdecebro mountain front, representing a capture by the Alfambra river occurred between 124 and 22 ka BP. [ABSTRACT FROM AUTHOR]