Seismotectonics and rupture process of the MW 7.1 2011 Van reverse-faulting earthquake, eastern Turkey, and implications for hazard in regions of distributed shortening

The 2011 October 23 MW 7.1 Van earthquake in eastern Turkey caused ~600 deaths and caused widespread damage and economic loss. The seismogenic rupture was restricted to 10-25 km in depth, but aseismic surface creep, coincident with outcrop fault exposures, was observed in the hours to months after the earthquake. We combine observations from radar interferometry, seismology, geomorphology and Quaternary dating to investigate the geological slip rate and seismotectonic context of the Van earthquake, and assess the implications for continuing seismic hazard in the region. Transient post-seismic slip on the upper Van fault started immediately following the earthquake, and decayed over a period of weeks; it may not fully account for our long-term surface slip-rate estimate of ≥ 0.5 mm yr-1. Post-seismic slip on the Bostaniçi splay fault initiated several days to weeks after the main shock, and we infer that it may have followed the MW 5.9 aftershock on the 9th November. The Van earthquake shows that updip segmentation can be important in arresting seismic ruptures on dip-slip faults. Two large, shallow aftershocks show that the upper 10 km of crust can sustain significant earthquakes, and significant slip is observed to have reached the surface in the late Quaternary, so there may be a continuing seismic hazard from the upper Van fault and the associated splay. The wavelength of folding in the hanging wall of the Van fault is dominated by the structure in the upper 10 km of the crust, masking the effect of deeper seismogenic structures. Thus, models of subsurface faulting based solely on surface folding and faulting in regions of reverse faulting may underestimate the full depth extent of seismogenic structures in the region. In measuring the cumulative post-seismic offsets to anthropogenic structures, we show that Structure-from-Motion can be rapidly deployed to create snapshots of postseismic displacement.We also demonstrate the utility of declassified Corona mission imagery (1960s-1970s) for geomorphic mapping in areas where recent urbanization has concealed the geomorphic markers

Human burial evidence from Hattab II Cave and the question of continuity in Late Pleistocene-Holocene mortuary practices in Northwest Africa

Archaeological excavations in 2002-3 at Hattab H Cave in northwestern Morocco revealed all undisturbed Late Palaeolithic Iberomaurusian human burial. This is the first Iberomaurusian inhumation discovered in the region. The skeleton is probably that Of a male aged between 25 and 30 years. The individual shows a characteristic absence of the central upper incisors reported in other Iberomaurusian burials. Accompanying the burial are a stone core and a number of grave goods including bone points, a marine gastropod and a gazelle horn core. Thermoluminescence dating of a burnt stone artefact in association with the burial has provided an age of 8900 +/- 1100 BP. This is one of the youngest ages reported for the Iberomaurusian and raises questions about persistence of hunter-gatherer societies in the Maghreb and the potential for continuity in burial practices with the earliest Neolithic

Neanderthals on the Lower Danube: Middle Palaeolithic evidence in the Danube Gorges of the Balkans

The article presents evidence about the Middle Palaeolithic and Middle to Upper Palaeolithic transition interval in the karst area of the Danube Gorges in the Lower Danube Basin. We review the extant data and present new evidence from two recently investigated sites found on the Serbian side of the Danube River – Tabula Traiana and Dubočka-Kozja caves. The two sites have yielded layers dating to both the Middle and Upper Palaeolithic and have been investigated by the application of modern standards of excavation and recovery along with a suite of state-of-the-art analytical procedures. The presentation focuses on micromorphological analyses of the caves’ sediments, characterisation of cryptotephra, a suite of new radiometric dates (accelerator mass spectrometry and optically stimulated luminescence) as well as proteomics (zooarchaeology by mass spectrometry) and stable isotope data in discerning patterns of human occupation of these locales over the long term

Neanderthals on the Lower Danube: Middle Palaeolithic evidence in the Danube Gorges of the Balkans

The article presents evidence about the Middle Palaeolithic and Middle to Upper Palaeolithic transition interval in the karst area of the Danube Gorges in the Lower Danube Basin. We review the extant data and present new evidence from two recently investigated sites found on the Serbian side of the Danube River – Tabula Traiana and Dubočka-Kozja caves. The two sites have yielded layers dating to both the Middle and Upper Palaeolithic and have been investigated by the application of modern standards of excavation and recovery along with a suite of state-of-the-art analytical procedures. The presentation focuses on micromorphological analyses of the caves’ sediments, characterisation of cryptotephra, a suite of new radiometric dates (accelerator mass spectrometry and optically stimulated luminescence) as well as proteomics (zooarchaeology by mass spectrometry) and stable isotope data in discerning patterns of human occupation of these locales over the long term

Changes to the Fossil Record of Insects through Fifteen Years of Discovery

The first and last occurrences of hexapod families in the fossil record are compiled from publications up to end-2009. The major features of these data are compared with those of previous datasets (1993 and 1994). About a third of families (>400) are new to the fossil record since 1994, over half of the earlier, existing families have experienced changes in their known stratigraphic range and only about ten percent have unchanged ranges. Despite these significant additions to knowledge, the broad pattern of described richness through time remains similar, with described richness increasing steadily through geological history and a shift in dominant taxa, from Palaeoptera and Polyneoptera to Paraneoptera and Holometabola, after the Palaeozoic. However, after detrending, described richness is not well correlated with the earlier datasets, indicating significant changes in shorter-term patterns. There is reduced Palaeozoic richness, peaking at a different time, and a less pronounced Permian decline. A pronounced Triassic peak and decline is shown, and the plateau from the mid Early Cretaceous to the end of the period remains, albeit at substantially higher richness compared to earlier datasets. Origination and extinction rates are broadly similar to before, with a broad decline in both through time but episodic peaks, including end-Permian turnover. Origination more consistently exceeds extinction compared to previous datasets and exceptions are mainly in the Palaeozoic. These changes suggest that some inferences about causal mechanisms in insect macroevolution are likely to differ as well

The Middle and Upper Pleistocene loess record and Acheulean-Mousterian industries of Saint-Illiers

A new sequence of loess / palaeosol has been found at Saint-Illiers (Yvelines) in western Paris Basin (France) in the context of an archaeological survey. The excavation yielded several levels of Palaeolithic artifacts comprising handaxes. An extensive study was carried out in order to get a reliable chronological framework. Together with micromorphology data, Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL) have been used to address this target. TL and OSL have been applied on burnt flints and sediments

OxGamma: A MATLAB based application for the analysis of gamma-ray spectra

Gamma-ray spectrometry is a well-established technique which enables to perform qualitative and quantitative analyses of gamma-ray emitting radionuclides. In trapped charge dating, portable spectrometers can be used to acquire spectra in the field, allowing for the assessment of radionuclide concentrations and hence the determination of dose rates at the exact location where samples are collected for dating. Accurate assessment of concentrations and dose rates demands proper energy, width, and efficiency calibration of the instrument by comparison against one or several radioactive standards. The ‘Oxford blocks’ which consist of four concrete cubes doped with known concentrations of potassium [K-block], thorium [Th-block], and uranium [U-block], as well as a background [BG-block], were constructed for this purpose and have become widely adopted by researchers for calibrating their instruments. For inexperienced users, the calibration of detectors and the analysis of field spectra for determining the concentration of radionuclides can be a challenging and laborious task that often involves multiple steps (e.g., downloading and converting data files, peak identification and selection, energy calibration, true full-peak area calculation, efficiency calculation, etc.). The processing of calibration spectra from the Oxford blocks is further complicated by the fact that the K-block contains only ∼72% concrete and the Th-block contains a small amount of uranium. These factors must be accounted for in order to obtain accurate radionuclide concentrations and dose rates. Here, we present a practical and user-friendly MATLAB based application (OxGamma), available as a free download for both Windows OS and macOS, intended to facilitate the calibration process of portable gamma-ray detectors and to provide a quick and efficient means for determining the concentration of radionuclides (K, U and Th) and dose rates. The software has been tested and checked against results obtained independently and provides output using both the windows and threshold approaches. Crucially, it does not require users to possess in-depth experience in programming or gamma-spectrometry

The Dzhungarian fault: Late Quaternary tectonics and slip rate of a major right-lateral strike-slip fault in the northern Tien Shan region

The Dzhungarian strike-slip fault of Central Asia is one of a series of long, NW-SE right-lateral strike-slip faults that are characteristic of the northern Tien Shan region and extends over 300 km from the high mountains into the Kazakh Platform. Our field-based and satellite observations reveal that the Dzhungarian fault can be characterized by three 100 km long sections based on variation in strike direction. Through morphological analysis of offset streams and alluvial fans, and through optically stimulated luminescence dating, we find that the Dzhungarian fault has a minimum average late Quaternary slip rate of 2.2 ± 0.8 mm/yr and accommodates N-S shortening related to the India-Eurasia collision. This shortening may also be partly accommodated by counterclockwise rotation about a vertical axis. Evidence for a possible paleo-earthquake rupture indicates that earthquakes up to at least Mw 7 can be associated with just the partitioned component of reverse slip on segments of the central section of the fault up to 30 km long. An event rupturing longer sections of the Dzhungarian fault has the potential to generate greater magnitude earthquakes (Mw 8); however, long time periods (e.g., thousands of years) are expected in order to accumulate enough strain to generate such earthquakes

New insights into the late Middle Stone Age occupation of Oued el Akarit, southern Tunisia

This article reports on a new project to investigate the activities of early Homo sapiens in the area of the Chotts 'megalake' in southern Tunisia. Excavations in 2015 and 2019 at Oued el Akarit revealed one of a number of Middle Stone Age (MSA) horizons near the top of a long sequence of Upper Pleistocene deposits. The site identified as Oued el Akarit (Sondage 8) consists of lithic artefacts, bone fragments of large ungulates and pieces of ostrich eggshell. Many of the objects are burnt. Excavation of about nine square metres revealed that these were associated with a lightly trampled and combusted occupation surface. Amongst the identified artefacts were Levallois flakes some of which could be refitted, thereby indicating the generally undisturbed nature of the occupation. The lithic finds also included side scrapers and other tools diagnostic of the MSA but significantly no bifacial or tanged tools. OSL (Optically Stimulated Luminescence) dating of the sediments and AMS (Accelerator Mass Spectrometry) radiocarbon dating of ostrich eggshell have produced uncalibrated age determinations in the range 37,000-40,000 years ago, one of the youngest ages for MSA sites in the region. This is the first example of a securely dated later MSA occupation in a riparian environment in south-eastern Tunisia