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Abstract Extensive Mesozoic rifting along the eastern North American margin formed a series of basins, including the Hartford basin in southern New England. Nearly contemporaneously, the geographically widespread Central Atlantic Magmatic Province (CAMP) was emplaced. The Hartford basin provides an ideal place to investigate the roles of rifting and magmatism in crustal evolution, as the integration of the dense SEISConn array and other seismic networks provides excellent station coverage. Using full‐wave ambient noise tomography, we constructed a detailed crustal model, revealing a low‐velocity (Vs = 3.3–3.6 km/s) midcrust and a high‐velocity (Vs = 4.0–4.5 km/s) lower crust beneath the Hartford basin. The low‐velocity midcrust may correspond to a layer of radial anisotropy due to extension and crustal thinning during rifting. The high‐velocity crustal root likely represents the remnant of magmatic underplating resulting from the CAMP event. Our findings shed light on crustal modification associated with supercontinental breakup, rifting, extension, and magmatism.
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This content will become publicly available on February 28, 2026
Imaging the Deformation Belt of Western Hispaniola Island (Haiti) Using Multi‐Component Ambient Noise Cross‐Correlations
Abstract We apply ambient noise tomography to a seismic array from the Trans‐Haiti project to obtain a 2‐D shear wave velocity (Vs) across Haiti. We perform multi‐component noise cross‐correlation, measure Rayleigh wave phase velocity and its horizontal‐to‐vertical amplitude ratio (H/V) between periods of 3–18 s, and jointly invert both measurements into Vs for the crustal structures of Haiti. Both H/V and phase velocity measurements exhibit consistent patterns related to the geologic units. Sedimentary basins—CSE and Plateau Central basins—show higher H/V values, while mountain areas—Massif de la Selle, Chaine des Matheux, Montagnes Noires and Massif de Nord—exhibit lower H/V. Regarding phase velocity, higher velocities are observed in northern and southern Haiti, likely reflecting the thinner crust compared to the thicker crust showing lower velocities in the central part. While our Vs model is consistent with previous model that suggested thinner crustal thickness in the northern and southern Haiti, with thickening in the center, the Moho interface in the central domain might be shallower than previously thought.
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- Award ID(s):
- 1753362
- PAR ID:
- 10616770
- Publisher / Repository:
- AGU Publications
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 52
- Issue:
- 4
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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