The long historical records of earthquakes, the physical effects on ancient building structures and the palaeoseismology provide a unique opportunity for an interdisciplinary tectonic analysis along a major plate boundary and a realistic evaluation of the seismic hazard assessment in the Middle East. We demonstrate with micro-topographic surveys and trenching that the Dead Sea Fault (DSF) offsets left-laterally by 13.6 0.2 m a repeatedly fractured ancient Roman aqueduct (older than AD 70 and younger than AD 30). Carbon-14 dating of faulted young alluvial deposits document the occurrence of three large earthquakes in the past 2000 years between AD 100 -750, between AD 700 -1030 and between AD 990 -1210. Our study provides the timing of late Holocene earthquakes and constrains the 6.9 0.1 mm/yr. slip rate of the Dead Sea transform fault in northwestern Syria along the Missyaf segment. The antepenultimate and most recent faulting events may be correlated with the AD 115 and AD 1170 large earthquakes for which we estimate M w = 7.3 -7.5. The 830 years of seismic quiescence along the Missyaf fault segment implies that a large earthquake is overdue and may result in a major catastrophe to the population centres of Syria and Lebanon.

SUMMARY The Serghaya fault, located approximately along the Syrian–Lebanese border, is a prominent structure within the 200 km restraining bend in the left‐lateral Dead Sea fault system. This study documents palaeoseismic and geomorphic expressions of Holocene movements on the Serghaya fault based on trench excavations and radiocarbon dates. Trenches were excavated across and parallel to a 4.5 m fault scarp where Late Pleistocene sediments are faulted against Holocene alluvium and colluvium. Locally oblique slip on the Serghaya fault has produced a sequence of fault‐derived colluvial wedges that distinguishes individual palaeoseismic events. In addition, the trench excavations also depict a sequence of buried and displaced channels. Our palaeoseismic study reveals evidence for five surface‐rupturing events within the past ∼6500 yr. The last event involved 2–2.5 m of primarily left‐lateral displacement and may correspond to one of two historically documented earthquakes during the 18th century (in 1705 and 1759). The displaced channels provide an estimated slip rate of approximately 1.4 ± 0.2 mm yr− 1 during the Holocene. The chronological relationships between the colluvial wedges and faulted channels demonstrate an average left‐lateral displacement of about 2 m per event, suggesting that such events correspond to earthquakes of M≳ 7 with a mean return time of about 1300 yr. These results demonstrate that the Serghaya fault may present a previously overlooked earthquake hazard for populations in the vicinity of the AntiLebanon Mountains, including the cities of Damascus and Beirut. In a regional context, the inferred slip rate along the Serghaya fault accounts for about 25 per cent of the total expected motion of Arabia relative to Africa along the Dead Sea fault system. The fact that the Serghaya fault accounts for only a fraction of the expected plate motion implies that the remaining strike‐slip and shortening must be accommodated by other active fault branches within the large restraining bend of the Dead Sea fault system. These results contradict suggestions that the northern Dead Sea fault system in Lebanon and Syria is presently inactive as a result of an evolving regional stress field in the eastern Mediterranean region.

Marine vertebrate faunas from the latest Cretaceous phosphates of the Palmyrides Chain of Syria are described for the first time. Recent fieldwork in the phosphatic deposits of the Palmyra area (mines of Charquieh and Khneifiss, outcrops of Bardeh, Soukkari and Soukhneh) have yielded a rich and diversified assemblage of marine vertebrates, including more than 50 species of chondrichthyes, osteichthyes, squamates, chelonians, plesiosaurians and crocodilians. Selachians are the most abundant and diverse component of the faunas and are represented by at least 34 species of both sharks and rays. Actinopterygians include representatives of six families, the most common being the enchodontids. Squamates are known by six mosasaurid species and an indeterminate varanoid. Chelonians are represented by at least two bothremydids and two chelonioids. Finally, elasmosaurid plesiosaurs and indeterminate crocodilians are also present in the fossil assemblages. The difference in faunal composition observed between the sites is interpreted as being due to palaeoecological preferences related to the Hamad Uplift palaeostructure. The marine vertebrate faunas of Syria show close affinities with those of the latest Cretaceous phosphatic deposits of North Africa and the Middle East and are typical of the southern Tethyan realm. From a biostratigraphical point of view, the selachians are the only suitable material to provide elements of an answer to the long debated question of the age of the Syrian Senonian phosphates. They suggest an Early Maastrichtian age for most of the phosphates of the Palmyrides Chain.

The historical sources of large and moderate earthquakes, earthquake catalogues and monographs exist in many depositories in Syria and European centers. They have been studied, and the detailed review and analysis resulted in a catalogue with 181 historical earthquakes from 1365 B.C. to 1900 A.D. Numerous original documents in Arabic, Latin, Byzantine and Assyrian allowed us to identify seismic events not mentioned in previous works. In particular, detailed descriptions of damage in Arabic sources provided quantitative information necessary to re-evaluate past seismic events. These large earthquakes (I0>VIII) caused considerable damage in cities, towns and villages located along the northern section of the Dead Sea fault system. Fewer large events also occurred along the Palmyra, Ar-Rassafeh and the Euphrates faults in Eastern Syria. Descriptions in original sources document foreshocks, aftershocks, fault ruptures, liquefaction, landslides, tsunamis, fires and other damages. We present here an updated historical catalogue of 181 historical earthquakes distributed in 4 categories regarding the originality and other considerations, we also present a table of the parametric catalogue of 36 historical earthquakes (table I) and a table of the complete list of all historical earthquakes (181 events) with the affected locality names and parameters of information quality and completeness (table II) using methods already applied in other regions (Italy, England, Iran, Russia) with a completeness test using EMS-92. This test suggests that the catalogue is relatively complete for magnitudes >6.5. This catalogue may contribute to a comprehensive and unified parametric earthquake catalogue and to a realistic assessment of seismic hazards in Syria and surrounding regions.

Biostratigraphic and carbon-isotope data were used to introduce a high-resolution stratigraphic reference section of the Upper Aptian to Upper Cenomanian platform carbonates of the South Palmyrides in Syria. We studied the biostratigraphic evolution of the Zbeideh to Abou-Zounnar formations in two sections, based on 42 species of benthonic foraminifera and 38 species of planktonic foraminifera. Comparisons with other Tethyan assemblages allowed determining 11 biozones; six are based on planktonic foraminifera, and five on benthonic foraminifera. Four hiatuses (earliest Albian, Middle–Late Albian, Late Albian–Early Cenomanian, and Mid Cenomanian) are marked by hardgrounds or dolomitic intervals. The planktonic biozones Ticinella bejaouaensis, T. primula, T. praeticinensis, Rotalipora subticinensis, R. globotruncanoides and R. cushmani co-occur with the following benthonic biozones: Mesorbitolina texana partial range zone, M. subconcava range zone, Neoiraqia convexa taxon-range zone, Praealveolina iberica interval zone and Pseudedomia drorimensis range zone. Within this biostratigraphic framework, a new carbon-isotope curve from the South Palmyrides was compared with δ13C records of the Tethyan Realm and England that allows identifying several biotic events and Oceanic Anoxic Events (OAE), recorded in the Upper Albian to Upper Cenomanian succession. The combination of sequence-stratigraphic interpretations and comparisons, with our results have led to an improved understanding of the Cretaceous platform architecture of the South Palmyrides that links the Arabian Platform to the east with the Levant Platform to the southwest.