Summary A new 1‐D velocity model along the southern Cuban margin has been determined using local earthquake data, which are the result of the merged Cuban and Jamaican catalogues. Simultaneous inversion using joint‐hypocentre determination was applied to solve the coupled hypocentre–velocity model problem. We obtained a seven‐layer model with an average Moho interface at 20 km. The average velocity was found to be 7.6 km s−1 on the top of the crust–mantle transition zone and 6.9 km s−1 in the basaltic layer of the crust. The improvement in the earthquake locations allowed us for the first time to use local seismicity to characterize the activity on local faults and the stress regime in the area. For this purpose, 34 earthquake focal mechanisms were determined along the eastern segments of the Oriente Fault. These solutions are consistent with the known left‐lateral strike‐slip motion along this major structure as well as with the stress regime of two local structures: (1) the Cabo Cruz Basin and (2) the Santiago deformed belt. The first structure is dominated by normal faults with minor strike‐slip components and the second by reverse faults. The shallow seismicity in the Cabo Cruz Basin is associated with fault planes trending N55°–58°E and dipping 38°–45° to the north. The Santiago deformed belt, on the other hand, exhibits diverse fault plane orientations. These local structures account for most of the earthquake activity along the southern Cuban margin. Deep seismicity observed in the Santiago deformed belt, supported by focal mechanisms, suggests underthrusting of the Gonave Microplate beneath the Cuban Block in this area. The principal stress orientations obtained from stress inversion of earthquake focal mechanisms suggest a thrust faulting regime along the Southern Cuban margin. We obtained a nearly horizontal σ1 and nearly vertical σ3, which indicates active compressional deformation along the major Oriente transcurrent fault in agreement with the dominant structural trend associated with the Santiago deformed belt.

We provide additional evidence of tectonic tremor in Cuba triggered by the 2010 M w 8.8 Maule, Chile, and the 2011 M w 9.0 Tohoku-Oki, Japan, earthquakes. The high-frequency tremor signals are modulated by long-period surface waves, similar to triggered tremors observed in other tectonically active regions. We are able to locate two tremor sources triggered by the Tohoku-Oki earthquake near the east-west trending Oriente fault around Guantanamo Bay. The tremor around Guantanamo Bay was triggered primarily by a Love wave of the Maule mainshock, and by both Love and Rayleigh waves of the Tohoku-Oki mainshock. This is consistent with frictional failures at a vertical strike-slip fault under a Coulomb failure criterion.

The joint inversion of Rayleigh wave group velocity dispersion and receiver functions has been used to study the crust and upper mantle structure at eight seismic stations in Cuba. Re- ceiver functions have been computed from teleseismic recordings of earthquakes at epicentral (angular) distances in the range from 30◦ to 90◦ and Rayleigh wave group velocity dispersion relations have been taken from earlier surface wave tomographic studies in the Caribbean area. The thickest crust (∼30 km) below Cuban stations is found at Cascorro (CCC) and Mais ́ı (MAS) whereas the thinnest crust (∼18 km) is found at stations R ́ıo Carpintero (RCC) and Guanta ́namo Bay (GTBY), in the southeastern part of Cuba; this result is in agreement with the southward gradual thinning of the crust revealed by previous studies. In the crystalline crust, the S-wave velocity varies between ∼2.8 and ∼3.9 km s–1 and, at the crust–mantle transition zone, the shear wave velocity varies from ∼4.0 and ∼4.3 km s–1. The lithospheric thickness varies from ∼65 km, in the youngest lithosphere, to ∼150 km in the northeastern part of the Cuban island, below Mais ́ı (MAS) and Moa (MOA) stations. Evidence of a subducted slab possibly belonging to the Caribbean plate is present below the stations Las Mercedes (LMG), RCC and GTBY whereas earlier subducted slabs could explain the results obtained below the Soroa (SOR), Manicaragua (MGV) and Cascorro (CCC) station

An overview of the S-wave velocity (Vs) structural model of the Caribbean with a resolution of 2° 9 2° is presented. New tomographic maps of Rayleigh wave group velocity disper- sion at periods ranging from 10 to 40 s were obtained as a result of the frequency time analysis of seismic signals of more than 400 ray-paths in the region. For each cell of 2° 9 2°, group velocity dispersion curves were determined and extended to 150 s by adding data from a larger scale tomographic study (VDOVIN et al., Geo- phys. J. Int 136:324–340, 1999). Using, as independent a priori information, the available geological and geophysical data of the region, each dispersion curve has been inverted by the ‘‘hedgehog’’ non-linear procedure (VALYUS, Determining seismic profiles from a set of observations (in Russian), Vychislitielnaya Seismologiya 4, 3–14. English translation: Computational Seismology (V.I. Keylis- Borok, ed.) 4:114–118, 1968), in order to compute a set of Vs versus depth models up to 300 km of depth. Because of the non- uniqueness of the solutions for each cell, a local smoothness optimization has been applied to the whole region in order to choose a three-dimensional model of Vs, satisfying this way the Occam’s razor concept. Several known and some new main fea- tures of the Caribbean lithosphere and asthenosphere are shown on these models such as: the west directed subduction zone of the eastern Caribbean region with a clear mantle wedge between the Caribbean lithosphere and the subducted slab; the complex and asymmetric behavior of the crustal and lithospheric thickness in the Cayman ridge; the predominant oceanic crust in the region; the presence of continental type crust in Central America, and the South and North America plates; as well as the fact that the bottom of the upper asthenosphere gets shallower going from west to east