Bahain, J.J., Duval, M., Voinchet, P., Tissoux, H., Falguères, C., Grün, R., Moreno, D., Shao, Q., Tombret, O., Jamet, G., Faivre, J.P., Cliquet, D.
Tourville-la-Rivière (Normandy, France) is one of the rare Middle Pleistocene palaeoanthropological localities of Northern France. Electron Spin Resonance (ESR) and combined ESR/U-series dating methods were independently applied by different teams on sediments and teeth from this site. The present work provides an overview of this multi-laboratory dating work by integrating a description and discussion of the methodologies employed and results obtained. Results confirm that the ESR/U-series analyses of the teeth are greatly dependent on the U-uptake histories of the dental tissues. Although all teeth come from the same archeological level, the samples analysed by each team display two different patterns for the U-series data. This is most likely related to the different sampling areas selected by each team and may be interpreted as the result of local variations in the geochemical conditions of the surrounding environment. Concerning the ESR dating of optically bleached quartz grains, the use of the multiple centre approach seems crucial when dating such fluvial and fluvio-lacustrine sediments. Our results also confirm the great potential of the Ti-H centre to date late Middle Pleistocene deposits. Despite some (expected) discrepancies related to the independent use of parameters and approaches by the different teams involved in this multi-laboratory study, the whole ESR and ESR/U-series data set collected from Tourville-la-Rivière locality consistently correlates stratigraphic levels D1 to I and associated human occupation to MIS7
Francisco Gutiérrez, Davinia Moreno, Gloria I. López, Fernando Jiménez, Miren del Val, MªJesús Alonso, Virginia Martínez-Pillado, Oswaldo Guzmán, David Martínez, Domingo Carbonel.
Geomorphology 363, 107233
The seismogenic potential of active faults for seismic hazard analyses are typically constrained using slip rates. These parameters, derived from numerically dated Quaternary deposits and landforms, have a critical impact on seismic hazard estimates with relevant societal and economic implications. Recently published geomorphological and paleoseismic investigations on active normal faults in the intraplate Iberian Chain (Spain), based on OSL ages from a now closed commercial laboratory, indicate anomalously high slip rates and paleoearthquake frequencies and extremely high fluvial incision rates. Parameters derived from those numerical ages have been used for seismic hazard assessments at critical facilities. This work revisits the chronology of Quaternary deposits associated with several faults applying various geochronological methods: Electron Spin Resonance (ESR), AMS Radiocarbon, Optically Stimulated Luminescence (OSL) and U-series dating. The totality of the new numerical ages is markedly different from the previously published OSL ages. The thirteen new ESR, OSL and U-series ages are systematically between three and six times older than the previous OSL ages. These data strongly suggest that previous ages overestimate the activity of the faults and seismic hazard in the region. The lack of validity of the revisited OSL analyses is attributed to inadequate dating procedures. Slip rates calculated with the new numerical ages are consistent with the slip rates estimated using Pliocene markers in the Iberian Chain and the slip rates published for other normal faults in eastern Spain. The new geochronological data also indicate reasonable fluvial incision rates, comparable with those estimated in nearby regions. The findings presented in this work have also implications for other Quaternary geomorphological studies in Spain based on potentially non-valid OSL ages.
Gutiérrez, F., Carbonel, D., Sevil, J., Moreno, D., Linares, R., Comas, X., Zarro, M., Roqué, C., McCalpin, J.P.
Journal of Structural Geology, 131. 103933
The official seismic hazard models in Spain used in the seismic building codes do not incorporate Quaternary faults, largely due to insufficient data for their proper characterization. There is an obvious need to conduct investigations in most of the recognised Quaternary faults to unambiguously demonstrate their Quaternary tectonic activity and assess their seismogenic potential. This work illustrates the integration of cartographic, tectonic, geomorphological, paleoseismological and geophysical methods for the characterization of the slow-moving extensional Daroca Fault, related to the negative inversion of the Alpine Daroca Thrust, Iberian Chain, NE Spain. Cartographic data indicate that the 27 km long Daroca Fault and the 17 km long Calamocha Fault, separated by a stepover 1.9 km wide, can be considered as segments of the same structure that might rupture jointly and generate Mw7 earthquakes. A long-term slip rate of 0.06–0.02 mm/yr has been estimated for the 27 km long Daroca Fault using an ESR-dated (Electro Spin Resonance) offset pediment. The work discusses why this slip rate is significantly lower than those estimated in nearby normal faults using OSL ages (Optically Stimulated Luminiscence), but comparable with those derived from offset early Pliocene limestones. A trench excavated across the Daroca Fault exposed evidence of the MRE (most recent event) on the fault, with bracketing ages of 2354–1544 cal yr BP (404 BC – 386 AD). This event likely caused the destruction and abandonment of Roman cities in the vicinity of the fault. Several explanations are proposed for the anomalously low vertical displacement of this surface faulting event recorded in the central sector of a 27 km long fault segment: multi-strand rupture, full-segment rupture, partial segment rupture, spillover rupture, and secondary sympathetic rupture.
Moreno, D., Duval, M., Rubio-Jara, S., Panera, J., Bahain, J.J., Shao, Q., Pérez-González, A. & Falguères, C.
Quaternary International, 520. 23-38
In this work, three important Pleistocene sites of the Madrid basin located close to the junction of the Manzanares (PRERESA site) and the Jarama (Valdocarros site and Maresa quarry) rivers have been studied in order to improve the existing chronological framework of the basin and to clarify the geological evolution of these fluvial systems and their relationship with human occupations. To do so, Electron Spin Resonance (ESR) dating was applied to four fossil teeth and nine optically bleached quartz grain samples. Most of the obtained dates are consistent with the existing preliminary age estimates by biostratigraphy, luminescence (OSL and TL) or Amino Acid Racemization (AAR) dating. This ESR dating study suggests an age of Late Middle Pleistocene (early MIS6) for PRERESA site. At the Jarama valley (Valdocarros site and Maresa quarry), the Arganda I unit could be correlated to the MIS 9 and MIS10, the Arganda II unit seems to belong to MIS8 and MIS7 and the Arganda III to the MIS6.
Del Val, M., Duval, M., Medialdea, A., Bateman, M.D., Moreno, D., Arriolabengoa, M., Aranburu, A. & Iriarte, E.
Quaternary Geochronology, 49, 108-114
Reported here is the first chronostratigraphic study of the Quaternary fluvial terrace deposits of three different valleys (Deba, Nerbioi, Oiartzun) located in the eastern Cantabrian margin (northern Spain), designed to understand long-term fluvial dynamics of this region. Fourteen samples were collected for numerical dating purpose, in the lowest terrace levels from 5 m to 63 m above current river channel. Optically Stimulated Luminescence dating was performed using the SAR protocol. For samples from terraces>20 m above the current river channel, over 20% of measured aliquots were above saturation of the OSL signal. Consequently, only minimum ages could be estimated. Five samples also underwent Electron Spin Resonance (ESR) dating following the Multiple Centre approach. The ESR signals of the Aluminium and Titanium (Ti-Li and Ti-H) centres were systematically measured in each sample. In particular, the ESR signal of the Ti-H centre was strong enough to derive reliable and meaningful dose estimates. Obtained age results range between∼140 and∼400 ka for the terrace levels from +10 to +25 m. They suggest phases of aggradation during MIS 6, MIS 8 and MIS 10, for terrace levels T+10m, T+20m and T+25m, respectively.