A probabilistic seismic hazard analysis has been performed to compute probabilistic seismic hazard maps for the eastern Caribbean region (10°N-19°N, 59°W-64°W), which includes in the north the Leeward Islands (from Anguilla to Dominica) and in the south the Windward Islands (from Martinique to Grenada), Barbados, Trinidad, and Tobago. The analysis has been conducted using a standard logic-tree approach that allowed systematically taking into account the model-based (i.e., epistemic) uncertainty and its influence on the computed ground motion parameters. Hazard computations have been performed using a grid of sites with a space resolution of 0.025 degrees covering the territory of the considered islands. Two different computation methodologies have been adopted: the standard Cornell-McGuire approach (Cornell, 1968; McGuire, 1976) based on the definition of appropriate seismogenic zones (SZ), and the zone-free approach developed by Woo (1996), which overcomes the ambiguities related with the definition of seismic sources. The interplay and complexities between shallow crustal, intraplate, and interface subduction seismicity of the Caribbean region have been thoroughly investigated. By merging all available databases, a comprehensive and updated earthquake catalog for the region has been compiled. Also, a thorough investigation has been undertaken to identify the most suitable ground motion prediction equations to be used in the analyses. Uniform hazard spectra have been calculated for the horizontal component of ground motion (rock and level site conditions), 4 return periods (RP) (95-, 475-, 975-, and 2475-yr), and 22 spectral accelerations (SA) with structural periods ranging from 0 to 3 s. SAs at 0.2 and 1.0 s for 2475-yr RP have been calculated to allow the definition of seismic hazard in the region of study according to the International Building Code (IBC, International Code Council [ICC], 2009).

The Central Italy earthquake sequence nominally began on 24 August 2016 with a M6.1 event on a normal fault that produced devastating effects in the town of Amatrice and several nearby villages and hamlets. A major international response was undertaken to record the effects of this disaster, including surface faulting, ground motions, landslides, and damage patterns to structures. This work targeted the development of high-value case histories useful to future research. Subsequent events in October 2016 exacerbated the damage in previously affected areas and caused damage to new areas in the north, particularly the relatively large town of Norcia. Additional reconnaissance after a M6.5 event on 30 October 2016 documented and mapped several large landslide features and increased damage states for structures in villages and hamlets throughout the region. This paper provides an overview of the reconnaissance activities undertaken to document and map these and other effects, and highlights valuable lessons learned regarding faulting and ground motions, engineering effects, and emergency response to this disaster.

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