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[EN] A system of active normal faults around the city of Cusco have severely damaged the city in major earthquakes in pre-hispanic times, 1650 and 1950 CE. Detailed studies of these faults adjacent to Cusco are therefore needed to build an understanding of seismic hazard in the region. We present new geomorphological and paleoseismological evidence for multiple Holocene earthquakes on the Tambomachay Fault, a 20 km-long normal fault that runs along the northern margin of the Cusco Basin. The western segment of the fault preserves fault scarps that cut moraine crests with a mean throw of 4.3 ± 0.4 m. We determine a 13.8 ± 0.6 ka depositional age of these moraines using 10Be cosmogenic surface-exposure dating of boulders embedded in the moraines, implying a Holocene-average fault slip rate of 0.3 ± 0.1 mm/yr. We also excavated a trench across the moraine crests. By reconstructing the trench stratigraphy with radiocarbon dating, we identified three surface-rupturing earthquakes over the last 8–9 ka. The oldest earthquake occurred between 8.5 and 8.3 ka, a second event between 6.8 and 5.5 kyrs, and the most recent earthquake between 1.2 and 0.9 ka. All of the ruptures predate Inca times (>1 ka). These surface-rupturing earthquakes are likely to have had moment magnitudes of Mw 6.4-6.9. Similar events have the capacity to severely damage modern-day Cusco due to their proximity to the city, which now has a population of 500,000.

Over the past decades, substantial progress has been made in tsunami research. Be that as it may, little is still known about tsunami deposits and their related depositional mechanisms in coastal areas in historical and archaeological contexts. In particular, the Phoenician, Greek and Roman trade and military networks along the Mediterranean and Atlantic coasts, with their cities, harbours and additional facilities, are susceptible to serving as archives for extreme wave events. The ruins of the Roman city of Baelo Claudia, located on the Bay of Bolonia Bay (southern Spain), offer a unique environment for studying historical tsunamis in the Gulf of Cadiz. Baelo Claudia suffered at least two earthquakes in Roman times, namely, in the first and fourth centuries CE. The latter, associated with a tsunami, led to the city’s destruction and subsequent decline. Accordingly, three tsunami deposits in Baelo Claudia, dated to ca. 4000 cal BP (2000 BCE), ca. 400 CE and 1755 CE, the last corresponding to the Lisbon tsunami, are described here. The multi-disciplinary research conducted on the sedimentary, archaeological and palaeontological records has revealed event deposits, together with major landscape changes in the environs of the bay after tsunami landfall. Furthermore, the significant archaeoseismic damage detected in recently excavated buildings has been dated to the end of the fourth-century CE. The results presented here serve to supplement the earthquake and tsunami record of coastal Iberia.

The Dinarides fold-thrust belt on the Balkan Peninsula resulted from convergence between the Adriatic and Eurasian plates since Mid-Jurassic times. Under the Dinarides, S-wave receiver functions, P-wave tomographic models, and shear-wave splitting data show anomalously thin lithosphere overlying a short down-flexed slab geometry. This geometry suggests a delamination of Adriatic lithosphere. Here, we link the evolution of this continental convergence system to hitherto unreported sets of extensively uplifted Oligocene–Miocene (28–17 Ma) marine terraces preserved at elevations of up to 600 m along the Dinaric coastal range. River incision on either side of the Mediterranean-Black Sea drainage divide is comparable to the amounts of terrace uplift. The preservation of the uplifted terraces implies that the most External Dinarides did not experience substantial deformation other than surface uplift in the Neogene. These observations and the contemporaneous emplacement of igneous rocks (33–22 Ma) in the internal Dinarides suggest that the Oligo-Miocene orogen-wide uplift was driven by post-break-off delamination of the Adriatic lithospheric mantle, this was followed by isostatic readjustment of the remaining crust. Our study details how lithospheric delamination exerts an important control on crustal deformation and that its crustal signature and geomorphic imprint can be preserved for millions of years.

El presente trabajo ilustra el estado del conocimiento sobre arqueosismología en la antigua ciudad romana de Baelo Claudia (Tarifa, Cádiz) tras casi quince años de investigaciones. Esta antigua ciudad romana se vio afectada por dos importantes terremotos en los años 40–60 AD y 260–290 AD. El primero de ellos afectó en mayor grado a la parte baja (costera) de la ciudad provocando importantes cambios urbanísticos y arquitectónicos (monumentalización) en respuesta a las labores de reconstrucción. El segundo de ellos provocó una mayor destrucción, cuya ruina progresiva desembocó en el abandono definitivo de la ciudad en el 365–390 AD. Se catalogan, cartografían y describen la mayor parte de los Efectos Arqueológicos de los Terremotos (EAEs) del sector monumental de la ciudad, que testifican los efectos producidos por el terremoto ocurrido en el 260–90 AD. La cartografía de daños (EAEs) muestra la distribución y orientación de los daños en la zona baja de la ciudad, así como la ocurrencia de otros procesos cosísmicos, como deslizamientos y pequeños tsunamis. El análisis estructural del conjunto de daños orientados indica que la dirección de movimiento del terreno se produjo en una dirección dominante del SO al NE. Los análisis geoarqueológicos, así como importantes anomalías constructivas y funerarias, sugieren la intervención de tsunamis de escaso poder de penetración durante los dos terremotos, apuntando a la existencia de una fuente sísmica submarina común al SSO de la ciudad. Se han identificado diferentes fallas normales de dirección N-S en la zona de la Bahía de Bolonia, algunas de las cuales se prolongan hacia el interior del mar en la zona SSO de Baelo Claudia. Estas fallas presentan claras evidencias de actividad Cuaternaria y podrían considerarse como las fuentes sísmicas más probables para los dos antiguos terremotos que afectaron a la ciudad en época romana.

El presente trabajo ilustra el estado del conocimiento sobre arqueosismología en la antigua ciudad romana de Baelo Claudia (Tarifa, Cádiz) tras casi quince años de investigaciones. Esta antigua ciudad romana se vio afectada por dos importantes terremotos en los años 40–60 AD y 260–290 AD. El primero de ellos afectó en mayor grado a la parte baja (costera) de la ciudad provocando importantes cambios urbanísticos y arquitectónicos (monumentalización) en respuesta a las labores de reconstrucción. El segundo de ellos provocó una mayor destrucción, cuya ruina progresiva desembocó en el abandono definitivo de la ciudad en el 365–390 AD. Se catalogan, cartografían y describen la mayor parte de los Efectos Arqueológicos de los Terremotos (EAEs) del sector monumental de la ciudad, que testifican los efectos producidos por el terremoto ocurrido en el 260–90 AD. La cartografía de daños (EAEs) muestra la distribución y orientación de los daños en la zona baja de la ciudad, así como la ocurrencia de otros procesos cosísmicos, como deslizamientos y pequeños tsunamis. El análisis estructural del conjunto de daños orientados indica que la dirección de movimiento del terreno se produjo en una dirección dominante del SO al NE. Los análisis geoarqueológicos, así como importantes anomalías constructivas y funerarias, sugieren la intervención de tsunamis de escaso poder de penetración durante los dos terremotos, apuntando a la existencia de una fuente sísmica submarina común al SSO de la ciudad. Se han identificado diferentes fallas normales de dirección N-S en la zona de la Bahía de Bolonia, algunas de las cuales se prolongan hacia el interior del mar en la zona SSO de Baelo Claudia. Estas fallas presentan claras evidencias de actividad Cuaternaria y podrían considerarse como las fuentes sísmicas más probables para los dos antiguos terremotos que afectaron a la ciudad en época romana.

The Arabian Sea is regarded as one of the least studied regions in terms of coastal hazards such as tropical cyclones and tsunamis. Parts of the coastline are developing rapidly, especially in Oman. This calls for a proper understanding of the natural processes that act on and affect it. This can be done by investigating the magnitude and impact of past events, in particular on human settlements. By doing this, future risks may not only be scientifically predicted and evaluated, but the damage caused by future events might even be mitigated. Evidence of past extreme wave events is preserved in the onshore stratigraphic record. In addition to this, the coastal zone of Oman is rich in archaeological remains. Presented here are the results of comprehensive mapping and analysis of extreme wave deposits of an archaeological site near Ras al-Hadd, suggesting that the Early Bronze Age site HD-6 was inundated at 4450 cal. BP. An event layer is identified between two settlement phases within the archaeological excavation. A contemporaneous sand bed with a maximum thickness of 0.4 m was mapped in the vicinity of the settlement. Ground penetrating radar surveys allow measurement of the thickness as well as identification of the internal facies architecture of the deposit. A high resolution digital elevation model reveals the coastal geomorphology. It is concluded that the causative event must have been a tsunami that was most likely generated within the Makran Subduction Zone. This interpretation does however, remain tentative at the moment Archaeological evidence indicates that the site was immediately re-occupied after the event, which attests to a certain resiliences of the Early Bronze Age coastal communities in the region.

The Lake Ohrid Basin in FYROM (Former Yugoslav Republic of Macedonia) and Albania meets all criteria of an active, seismic landscape: linear step-like fault scarps in the landscape and under water within the lake. Post-glacial (or Late Pleistocene) bedrock fault scarps at Lake Ohrid are long-lived expressions of repeated surface faulting in tectonically active regions, where erosion cannot outpace the fault slip. Other morphotectonic features are wind gaps, wineglass-shaped valleys and triangular facets, which are well preserved. Generally, the faults and fault scarps are getting younger towards the basin centre, as depicted on seismic and hydroacoustic profiles. Additionally, mass movement bodies within the lake and also onshore (rockfalls, landslides, sub-aquatic slides, homogenites, turbidites) are likely to have been seismically triggered. These morphotectonic observations are in line with focal mechanisms of earthquakes in the greater Lake Ohrid area. We investigated the neotectonic history and tectonic geomorphology of the Lake Ohrid Basin by means of an integrated multidisciplinary approach, using tectonic geomorphology and a variety of geophysical and remote sensing methods.

The Lake Ohrid Basin in FYROM (Former Yugoslav Republic of Macedonia) and Albania meets all criteria of an active, seismic landscape: linear step-like fault scarps in the landscape and under water within the lake. Post-glacial (or Late Pleistocene) bedrock fault scarps at Lake Ohrid are long-lived expressions of repeated surface faulting in tectonically active regions, where erosion cannot outpace the fault slip. Other morphotectonic features are wind gaps, wineglass-shaped valleys and triangular facets, which are well preserved. Generally, the faults and fault scarps are getting younger towards the basin centre, as depicted on seismic and hydroacoustic profiles. Additionally, mass movement bodies within the lake and also onshore (rockfalls, landslides, sub-aquatic slides, homogenites, turbidites) are likely to have been seismically triggered. These morphotectonic observations are in line with focal mechanisms of earthquakes in the greater Lake Ohrid area. We investigated the neotectonic history and tectonic geomorphology of the Lake Ohrid Basin by means of an integrated multidisciplinary approach, using tectonic geomorphology and a variety of geophysical and remote sensing methods.

The Roman archaeological site of Baelo Claudia (Cádiz, south Spain) is located within the Gibraltar Arch, a region with no significant recent or historical seismicity. However, previous studies have emphasized the occurrence of repeated strong archaeoseismic damage (intensity≥IX MSK) at Baelo Claudia tentatively bracketed in this study around ad 40–60 and ad 260–290. A multidisciplinary study has been carried out including the detailed mapping of surface deformation and building damage, surface geology and geomorphology, collection of structural data, and an extensive ground penetrating radar (GPR) survey. The obtained data are not conclusive when considered separately, but evident links between archaeoseismic damage, structural and GPR data indicate that the destruction of the city was linked to seismic shaking. The analysis of the pattern and orientation of deformation clearly indicates SW–NE directed compression due to ground shaking. This analysis also focuses on localized landslides and liquefaction processes, which appear to be coeval with the earthquakes, but the poor geotechnical parameters of the clayey substratum were determinant to amplify the observed level of destruction. The application of the present Spanish seismic code (NCSE-02) indicates that intensity VIII MSK (0.24–0.26 g) can be reached in this zone for 500 year return periods.