AD Earthquake Research Articles

Historical earthquakes in the Holy Cross Mountains, Poland, true or false? Unveiling insights through archaeoseismology

The Holy Cross Mountains are an intraplate range with a limited historical seismicity record. The only documented earthquakes include the February 6, 1837 M 4.3 event, which caused ground cracks, and swarm events from February 1932 (M ∼ 3.5), likely triggered by the Holy Cross Fault (HCF) or sub-perpendicular faults. The apparent lack of older destructive earthquakes in historical catalogs motivated us to conduct archaeoseismological research to improve seismic hazard assessment, risk mitigation, and urban planning strategies, ultimately benefiting local communities. We focused on the 12th-century Collegiate church of Saint Martin in Opatów, located near the Holly Cross Fault (HCF). We report numerous damage features, such as leaning, bulging, and twisted walls, dropped keystones in Romanesque and Gothic portals, strike-slip displacements of these portals, surplus, oversized buttresses, and walled-up portals. While some deformations may result from humid loess instability and war destructions, our data, combined with historical records, suggest two to three seismic events in the past 800 years as a cause. We argue these deformations were co-seismically triggered by either large far-field events, like the 1259 AD earthquake, or local, shallow small-magnitude events significantly amplified by site effects. This indicates potential seismic activity in the Holy Cross Mountains during Medieval times. The absence of historical records does not imply the absence of earthquakes.

Surface rupture history and 18 kyr long slip rate along the Pazarcık segment of the East Anatolian Fault

We investigate the palaeo earthquakes and slip rate on the Pazarcık segment of the East Anatolian Fault, which was involved in the surface rupture of the 6 February 2023 Pazarcık–Kahramanmaraş earthquake (M w 7.7) and provided insights into the long-term behaviour of this major continental fault. Palaeoseismological data from two trench sites reveal evidence for at least five surface ruptures in the Holocene Period. The historical earthquake of AD 1114 is verified at both trench sites but the following event of AD 1513 is identified at only one site. In addition, the age difference of the older events shows that historical activity is separated by much longer periods of relative quiescence that range from 500 to 1000 years, which suggests quasiperiodic earthquake occurrence on sub-segments of the Pazarcık segment. Our fault-parallel trenches revealed 101 ± 5 m offset in the last 18 kyr and 51 ± 1 m offset in the last 9 kyr on a buried stream channel and the actual channel of the same stream respectively. The correlation of the maximum and abandonment age of the channel with measured offsets revealed a 5.6 mm a −1 long-term slip rate of the fault. Supplementary material: A table and figures providing details of radiocarbon ages and trench sites are available at https://doi.org/10.6084/m9.figshare.c.6850786

A State-of-The-Art Technical Review on Seismic Resilience of Rcc Structural Components Using Seismic Resistance Based Retrofitting Techniques

Existing buildings can be at a greater seismic risk due to non-conformance to current design codes and may require structural retrofitting to improve building performance. The most recent example of that can be seen from the 2015 AD earthquake in Nepal and other sub continental regions, where numbers of buildings were destroyed with more fatal consequences have drawn the attention of the government authorities of Nepal and the general public for seismic earthquake resistance design of buildings. Following the post seismic assessment of building in Nepal after 2015 earthquake, it is revealed that the existing reinforced concrete buildings have some inadequacies in structural components and thus the intensive research and study is required to for the better understanding of the structure in terms of immediate consequences due to direct damage and way to recovery using seismic retrofit assessment.
 This paper presents an overview on performance based evaluation of retrofitted rcc structural member using some advanced retrofitting techniques which is innovative and can be cost effective retrofitting strategies demanding less skilled man power. It is concluded that better seismic resilience can be achieved with the help of innovative methods with the application of innovative materials like textile mortars and fibers. In the following sections a review of experimental flexural loading on beam is presented.

Assessment of Run-Up Height and Arrival Time of 365 AD Tsunami at Lampedusa Island, Italy

The eastern Mediterranean Sea is a subduction zone between the African plate and the Eurasian plate that has high seismicity. The tsunami of July 21, 365 AD was one of the most severe in the region, and its impact was estimated to have extended to the islands around the Aegean Sea, Cyprus, southern Calabria, Sicily, Malta, and Lampedusa. However, an analysis of tsunami waves reaching Lampedusa Island has not been conducted. Therefore, this study will present the run-up height and arrival time of tsunami waves near the Lampedusa coast. The methods applied are linear and non-linear shallow water equations by inputting the rupture parameters of the 365 AD earthquake. We used Delft Dashboard and Delft3D software to simulate tsunami wave propagation offshore. The simulation results indicate that an earthquake with a magnitude of approximately Mw 8.5 triggered tsunami waves with a maximum run-up height of 2.02 m in nearshore Lampedusa. The travel time for the maximum run-up height was 3.5 hours after the generation of the first tsunami wave in the western Hellenic Arc, Greece. We infer that seawater most likely inundated the coast of Lampedusa during the tsunami earthquake in 365 AD.

Imprints of the Little Ice Age and the severe earthquake of AD 2001 on the aquatic ecosystem of a tropical maar lake in El Salvador

Using a 530-year sediment record from the maar Lake Apastepeque, El Salvador, and based on diverse geochemical and biological (cladocerans, chironomids, diatoms, ostracods, testate amoebae) indicators, we estimated climatic and environmental alterations during the Little Ice Age (LIA) and reconstructed the recent history of the lake. Results demonstrate relatively humid conditions in the mid-elevations (500 m a.s.l.) of El Salvador during most parts of the LIA, resulting in high lake levels. Contrarily, the first part of the LIA was characterized by drier climates comparable to studies from Mexico and Belize, which correlated this phase with the Spörer minimum. Regional comparison with palaeorecords from the northern Neotropics reveals a high heterogeneity in local expressions of the LIA in Central America, likely connected to the high topographic heterogeneity of the region. Since the beginning of the 20th century, Lake Apastepeque has experienced enhanced human impact expressed as increased nutrient supply. The most recent period was characterized by significant environmental disturbance, which we relate to an upper-crustal earthquake, one of the strongest over the last 500 years, that affected the region on 13th February 2001 (Mw = 6.6, epicentre at 10 km depth, 30 km from the lake). The release of toxic bottom components such as hydrogen sulphide and high turbidity and turbulence of water caused major species turnover in the lake ecosystem, resulting in a massive fish kill and colonization by large cladocerans. Modern sediments still show slightly altered biota communities compared to pre-earthquake assemblages, indicating that the ecosystem has still not fully recovered.

Age of the late Holocene Bonneville landslide and submerged forest of the Columbia River Gorge, Oregon and Washington, USA, by radiocarbon dating

AbstractThe late Holocene Bonneville landslide, a 15.5 km2 rockslide-debris avalanche, descended 1000 m from the north side of the Columbia River Gorge and dammed the Columbia River where it bisects the Cascade Range of Oregon and Washington, USA. The landslide, inundation, and overtopping created persistent geomorphic, ecologic, and cultural consequences to the river corridor, reported by Indigenous narratives and explorer accounts, as well as scientists and engineers. From new dendrochronology and radiocarbon dating of three trees killed by the landslide, one entrained and buried by the landslide and two killed by rising water in the impounded Columbia River upstream of the blockage, we find (1) the two drowned trees and the buried tree died the same year, and (2) the age of tree death, and hence the landslide (determined by combined results of nine radiocarbon analyses of samples from the three trees), falls within AD 1421–1455 (3σ confidence interval). This result provides temporal context for the tremendous physical, ecological, and cultural effects of the landslide, as well as possible triggering mechanisms. The age precludes the last Cascadia Subduction Zone earthquake of AD 1700 as a landslide trigger, but not earlier subduction zone or local crustal earthquakes.

From 2D and 3D documentation to 4D interpretation. Building archaeological conclusions and workflow strategies gained by remote study of Insula V 1, Pompeii

The text describes new methods elaborated for and used in the building archaeological assessment of a city block, studied first on site, then remotely by members of the Swedish Pompeii Project. Use of a digital platform, with collected wall observations and analysis, systematic photographic documentation of all standing structures, and 3D models, allowed discussion to proceed after the fieldwork came to an end. The models provided new possibilities and new angles of approach, e.g. examining walls at any given point, studying boundary walls as wall-strings in their full extent, allowing all kinds of sectioning at will, introducing bird’s-eye views as a new perspective in study, and measuring wherever needed. The joint results obtained are summed up in a four-phase development of the use of space: the earliest structures; the late Samnite building boom (2nd century BC); the colony (second half of 1st century BC); the imperial era (until AD 79). This narrative includes conclusions concerning building process and development of masonry techniques and on changes in way of life. Many results affect Pompeian archaeology in general. Results of particular importance concern the character of the early plot division and the understanding of the building process creating the double-atrium house of Caecilius Iucundus, including an anchorage in time for this creation in the Claudian period. The relatively small impact in terms of damage that may be ascribed the literary recorded earthquake of AD 62/63 is also worth noting. The text ends with a suggestion of a new workflow for insula studies.

Archaeoseismological study of the Cherichira aqueduct bridge, Kairouan, Tunisia

In the past, several destructive earthquakes have occurred in the North African Atlas Mountain ranges located along the Africa–Eurasia plate boundary. Although the region is rich with impressive archaeological sites, including those in modern Tunisia, few comprehensive archaeoseismological studies have been conducted. Historic sources account at least three damaging earthquakes in the Kairouan area in central Tunisia between AD 859 and 1041. Little is known about which faults triggered these earthquakes or the size of these events. The water supply of the city of Kairouan depended on a 32-km-long aqueduct with a large bridge (now partially collapsed) at the confluence of the de Mouta and Cherichira rivers. The original bridge of Roman construction was retrofitted twice during the Aghlabid period (AD 800–903) and probably in AD 995 during the Fatimid period. The ruined section of the bridge shows damage which might be related to the AD 859 earthquake shaking. Here, we present a detailed study of the history, the status and the damage of the Cherichira aqueduct bridge using previous historic accounts and written works, a 3D laser scan model, local geological and seismological characteristics, and include results of radiocarbon dating and a timeline of events. In addition to earthquake ground motions, we consider severe flash floods on the bridge as a potential cause of the damage. We estimate the severity of such flash floods and develop a model with 18 earthquake scenarios on local reverse and strike-slip faults with magnitudes between MW 6.1 and 7.2. While a few damage patterns might be indicative of flooding, most damage can be attributed to earthquakes. It is highly probable that the earthquake in AD 859 caused enough damage to the Aghlabid bridge to render it dysfunctional; however, to resolve the question of whether another earthquake in AD 911 or 1041 caused the complete destruction of the previously retrofitted aqueduct by the Fatimids requires dating of additional sections of the bridge.

Preliminary report on salvage excavation at the southern limit of ancient Balagrae (modern al-Beida)

AbstractThis article presents a preliminary report on a rescue excavation conducted during the building of a new mosque close to the campus of Omar al-Mokhtar University at Balagrae (al-Beida) in 2017. The excavation, undertaken by the Department of Archaeology at the university, revealed the remains of part of a building with a mosaic floor built in the late second or early third century AD, and perhaps destroyed by an earthquake in AD 365. The discovery created considerable local interest and resulted in the developers relocating south the new mosque to prevent further disturbance to the archaeological remains. The building was carefully backfilled for long-term protection.

A Historical Earthquake-Induced Landslide Damming Event at the Qiaojia Reach of the Jinsha River, SE Tibetan Plateau: Implication for the Seismic Hazard of the Xiaojiang Fault

In bedrock mountainous areas where active faults and deep river valleys interact, earthquake-induced landslides can be used to explore local seismic hazards. The intersection of the highly active Xiaojiang Fault and the Jinsha River and its main tributaries in southwest China is a site of abundant earthquake-induced landslides. We found some boulders inappropriately scattered on the east bank of the Qiaojia reach of the Jinsha River, where the Qiaojia Segment of the Xiaojiang Fault passes through. We investigated the lithology and topography nearby and confirmed its source area, as well as the existence of a landslide damming event in the field. A high-resolution Digital Surface Model (DSM) generated from Unmanned Aerial Vehicle (UAV) images was used to analyze its characteristics and calculate its parameters. Optically Stimulated Luminescence (OSL) and 14C dating methods on the related dammed lake sand shows the age of the landslide, which is not later than 878 AD. The characteristics of large size with limited depositional extent, spatial relevance between the landslide and Xiaojiang Fault, and temporal-coincidence of the landslide with 624 AD earthquake support the seismic origin of this landslide. Moreover, the 624 AD earthquake was reanalyzed for its magnitude and macro-epicenter based on the coseismic displacement of the Heishui River floodplain. It was calculated to be Mw7.7 or Ms7.9 and relocated to the Qiaojia area. No M ≥ 7 earthquakes have occurred on the Qiaojia Segment for nearly 1,400 years since 624 AD. The elapsed time is close to the average recurrence interval of large earthquakes on the Qiaojia Segment. Therefore, the seismic hazard of the Qiaojia area should be considered in the future.

Co-seismic beachrock deformation of 8th century AD Earthquake in Middle Strand of North Anatolian Fault, Lake Iznik, NW Turkey

A historical earthquake-related co-seismic deformation observed on beachrock beds along the southern shoreline of Lake Iznik is discussed as a new paleoseismic record for an 8th century AD earthquake in the Middle Strand of the North Anatolian Fault, NW Turkey. Electrical Resistivity Tomography (ERT) images beneath the beachrock surface allowed monitoring of the subsurface trace of a normal fault dipping north along a 100 m surface rupture. No strike-slip deformation exists along the rupture, suggesting that the deformation in the beachrock is connected with a secondary structure, and that the main surface rupture was under the lake waters. The deformed beds of the beachrock, dated using Optically Stimulated Luminescence (OSL) to 1.3 ± 0.15 ka, are overlain by an undeformed secondary deposition of beds dated to 1.2 ± 0.09 ka. This allows us to narrow down the time of the faulting and implying that it was most likely a result of the AD 715 earthquake.

Tsunamis and submarine landslides in Suruga Bay, central Japan, caused by Nankai–Suruga Trough megathrust earthquakes during the last 5000 years

Magnitude 8 megathrust earthquakes that have generated large tsunamis with wave heights of >5 m in coastal areas of southwestern Japan have occurred every 100–150 years along the Nankai–Suruga Trough, which marks the convergent boundary between the Eurasian and Philippine Sea plates. Using sedimentological, geochemical, and paleontological analyses, as well as 14C dating, we examined tsunami deposits in 12 sediment cores collected from the Hamatome lowland, Yaizu Plain, Shizuoka, which faces the Suruga Trough. Four sandy tsunami deposits (Sands 1–4) are identified in sediments deposited during the last 5000 years. Sand 1 was deposited between 805 and 405 BC, suggesting that only one tsunami left a sedimentological imprint in the Hamatome lowland lagoon during the period of ∼4000 years between 3090 and 2913 BC and the AD 1096 Eicho-Tokai earthquake. This very low frequency of tsunami inundation may suggest that this tsunami was larger than those typically associated with megathrust earthquakes. Sands 2–4 are correlated with tsunamis associated with the Eicho-Tokai, AD 1361 Shohei-Koan, and AD 1498 Meio-Tokai earthquakes, respectively. Our data indicate that a sand spit, which had previously protected the lagoon from oceanic waves, was abruptly destroyed following the AD 1096 Eicho-Tokai earthquake and did not re-form at the same location. This disappearance of the sand spit is inferred to have involved an earthquake-induced submarine landslide. The data presented in this paper, together with information obtained from historical documents, indicates that M8 megathrust earthquakes in AD 1096 and AD 1498 caused submarine landslides in the study area, resulting in coastal subsidence and damage to coastal areas additional to that caused by the tsunamis.

Coastal subsidence, destruction layers and earthquakes from an underwater archaeological excavation: Kenchreai, eastern harbour of Roman Corinth, Greece

One of the first underwater coastal archaeological excavations was made in the 1960 in Kenchreai (Cenchreae), eastern harbour of Roman Corinth, Greece, near the Isthmus (Corinth) Canal. This excavation brought to light an Isis temple with a destruction layer containing amongst others, packs of more than 100 precious glass panels of opus sectile, testifying to a hitherto unknown mosaic-type wall decorative technique. Above this destruction layer, indicating a violently disrupted renovation of the temple in circa AD 400, thereafter abandoned, an apsidal Christian chapel was constructed, currently also found quasi-submerged. The excavators, inspired by subsidence of piscinae (fishtanks) and theories for earthquake destruction and decline of Roman Corinth, a prosperous town controlling marine routes and commerce between Eastern Mediterranean and Italy, have explained the environmental and occupation history of Kenchreai in terms of three earthquakes with 2.3 m cumulative subsidence. This theory, however, has been challenged on different grounds. New evidence about the glass panels and detailed evaluation of historical, seismological, archaeological and coastal data revealed an about 1 m seismic subsidence of Kenchreai, most of which occurred during a destructive earthquake in circa AD 400, undoubtedly with serious impacts to Corinth. Identification of the causative fault is not easy because of unfavourable lithology and because Kenchreai is in a tectonically complex environment: at the east edges of the uplifting Corinthian coast (marked by a Roman harbour 4 m above water) and of the Isthmus of Corinth, a Plio–Quaternary uplifted horst, inside an active tectonic graben. Kenchreai represents one of the very few cases of seismic coastal subsidence deriving from archaeological data.

Morphology and spatio-temporal distribution of lacustrine mass-transport deposits in Wörthersee, Eastern Alps, Austria

Abstract In lakes, landslides can be studied in high resolution due to their accessibility and limited size. Here, we investigate mass-transport deposits in glacigenic Wörthersee (Eastern European Alps) by integration of seismic, sediment core and multibeam bathymetric data. Two outstanding landslide events were revealed: the first occurred in the Late Glacial, leading to multiple deposits of up to 15 m thickness; they consist of sandy turbidites and mudclast conglomerates, which are overlain by a 2.5 m thick megaturbidite. The extensive, likely earthquake-triggered failure linked to this event was preconditioned by rapid sedimentation of fine-grained glaciolacustrine sediments and associated build-up of excess pore pressure. The second event was presumably triggered by a major earthquake (M w ≈7) in AD 1348 and comprises a mass-transport complex and several landslides, which led to a c. 30 cm thick turbidite. In total, 62 landslides are imaged in the multibeam map, 6 of which are most likely human-induced. Some of these show horseshoe-type compressional ridges and frontal breaching, whereas others exhibit an extensive zone of rafted blocks. We attribute these morphological differences to four main factors: (1) slope gradient and changes therein; (2) preconditioning of the impacted zone; (3) volume of remobilized sediment; and (4) type of impactor.

Parameters of the AD 849 earthquake east of Baotou City in Inner Mongolia and the adjustion of the potential seismic sources zone spatial distribution functions

According to volume 18 (<i>Xuanzong Ji Tang</i>) of the historical book entitled the <i>Old Book of Tang</i>, the Hetao area of Inner Mongolia experienced a large earthquake in AD 849. However, previous work on that earthquake contains many discrepancies regarding its epicenter location, magnitude, deaths, and intensity. While exploring active faults in Baotou City, the present authors mapped the Daqing Mountain piedmont fault geologically. Based on previous work, several seismic deformation traces of more than 1000 years ago were found, and dating tests were conducted. The research showed the Daqing Mountain piedmont fault zone to be the seismogenic structure of the AD 849 earthquake. The length of earthquake surface rupture zone was around 80 km, and the macro epicenter was located in the active fault. The deformation center was located at 40.6°N, 110.2°E. By collecting and analyzing more historical data about the AD 849 earthquake, reinterpreting some existing historical data, and re-examining the contradictory numbers of deaths in the historical data, the present analysis concludes that around 10,000 people were dead. It is suggested that this earthquake had a magnitude of 7½. According to the revised seismic parameters and the paleoearthquake recurrence period of the Daqing Mountain piedmont fault, the boundary of some potential seismic sources zone in the Baotou area are adjusted and the recurrence period of <i>M</i>8 and <i>M</i>7.5 are re-calculated.

Active tectonics in the Assam seismic gap between the meizoseismal zone of AD 1934 and 1950 earthquakes along eastern Himalayan front, India

The Assam Seismic Gap has witnessed a long seismic quiescence since the \({ Mw}{\sim }8.4\) great Assam earthquake of AD 1950. Owing to its improper connectivity over the last decades, this segment of the Himalaya has long remained inadequately explored by geoscientists. Recent geodetic measurements in the eastern Himalaya using GPS document a discrepancy between the geologic and geodetic convergence rates. West to east increase in convergence rate added with shorter time span earthquakes like the 1697 Sadiya, 1714 (\({ Mw}{\sim }8\)) Bhutan and 1950 (\({ Mw}{\sim } 8.4\)) Tibet–Assam, makes this discrepancy more composite and crucial in terms of seismic hazard assessment. To understand the scenario of palaeoearthquake surface rupturing and deformation of youngest landforms between the meizoseismal areas of \({ Mw}{\sim }8.1\) 1934 and 1950 earthquakes, the area between the Manas and Dhanshiri Rivers along the Himalayan Frontal Thrust (HFT) was traversed. The general deformation pattern reflects north-dipping thrust faults. However, back facing scarps were also observed in conjugation to the discontinuous scarps along the frontal thrust. Preliminary mapping along with the published literature suggests that, in the eastern Himalayan front the deformation is taking place largely by the thrust sheet translation without producing a prominent fault-related folds, unlike that of the central and western Himalayas.

Non-Destructive Multi-Analytical Approach to Study the Pigments of Wall Painting Fragments Reused in Mortars from the Archaeological Site of Pompeii (Italy)

During the excavations carried out in Via di Mercurio (Regio VI, 9, 3) in Pompeii, in 2015, some red, green, black, and brown wall painting fragments were found in the preparatory layer of an ancient pavement which was probably built after the 62 AD earthquake. These fragments, derived from the rubble, were used as coarse aggregate to prepare the mortar for building the pavement. The wall painting fragments are exceptionally well preserved, which is an uncommon occurrence in the city of Pompeii. However, as they were enclosed in the mortar, the wall painting fragments were protected from the high temperatures (probably ranging between 180 °C and 380 °C) produced by the eruption in 79 AD. The pigmented outer surface of each sample was analyzed using a non-destructive multi-analytical approach, by combining spectrophotometric colorimetry and portable X-ray fluorescence with micro-Raman spectroscopy. The compositional characterization of the samples revealed the presence of cuprorivaite, goethite, and celadonite in the green pigments; hematite in the red pigments; goethite in the brown pigment; and charcoal in the black pigment. These data probably provide us with the most “faithful picture” of the various red, green, black, and brown pigments used in Pompeii prior to the 79 AD eruption.

Accurate surface exposure dating with lichens

AbstractLichenometry accurately dates exposure times of glacial moraines and landslides when measuring the longest axis of the largest crustose lichen on many blocks, as demonstrated by numerous examples. In Sweden, the sizes ofRhizocarponsubgenusRhizocarpondescribe five pulses of glacial moraine creation in 120 yr. Six historic California earthquakes, between AD 1800 and 1906, caused many landslides that constrain lichen growth as linear with a dating accuracy of±0.5 yr. Crustose lichen sizes date earthquake-created additions to Sierra Nevada talus with an accuracy of±5 yr. The oldest lichen ages are 400 yr forLecanora sierrae, 800 yr forLecidea atrobrunnea, and 1100 yr forAcarospora chlorophanaandRhizocarponsubgenusRhizocarpon. Lichen sizes also record differing spatial attenuation of ground shaking from the magnitude (Mw) ~7.9 San Andreas earthquake of AD 1857 and the more distant, smaller San Jacinto AD 1800 earthquake, which both caused Sierra Nevada rockfalls. AD 1800 seismic shaking was relatively stronger than that of AD 1857 farther north, perhaps expressing stronger Love and Rayleigh styles of surface waves from the north-trending AD 1800 surface rupture that were particularly efficient in causing rockfalls at greater distances.

Recognition of Earthquake-Induced Damage in the Abakainon Necropolis (NE Sicily): Results From Geomorphological, Geophysical and Numerical Analyses

Seismotectonic activity and slope instability are a permanent threat in the archaeological site of Abakainon and in the nearby village of Tripi in NE Sicily. In recent times, signs of an ancient earthquake have been identified in the necropolis of Abakainon which dating was ascertained to the first century AD earthquake. The site is located on a slope of Peloritani Mts. along the Tindari Fault Line and contains evidence for earthquake-induced landslide, including fallen columns and blocks, horizontal shift and counter slope tilting of the tomb basements. In this paper, we used an integrated geomorphological and geophysical analysis to constrain the landslide. The research was directed to the acquisition of deep geological data for the reconstruction of slope process and the thickness of mobilized materials. The applied geophysical techniques included seismic refraction tomography and electrical resistivity tomography. The surveys were performed to delineate the sliding surface and to assess approximately the thickness of mobilized materials. The geophysical and geomorphologic data confirmed the presence of different overlapped landslides in the studied area. Moreover, a numerical simulation of the slope under seismic loads supports the hypothesis of a mobilization of the landslide mass in case of strong earthquakes (PGA > 0.3 g). However, numerical results highlight that the main cause of destruction for the Abakainon necropolis is the amplification of the seismic waves, occasionally accompanied by surficial sliding.

Mosaicists at work: the organisation of mosaic production in Early Islamic Jerash

Abstract