Shoreline crossing Moho geometry of the Cascadia slab: CascadiaMoho1.0
DOI:
https://doi.org/10.26443/seismica.v2i4.1674Abstract
Accurate characterization of subducting slab geometry is fundamental to understanding the distribution of earthquakes, the dynamics of arc volcanism, and the assessment of seismic hazards. Well-constrained slab structures also serve as critical inputs for geophysical imaging and geodynamic modeling efforts that aim to resolve key processes in subduction zones. In this study, we present a comprehensive, margin-wide model of the Moho associated with the subducting oceanic plate beneath the Cascadia subduction zone, developed through the integration of publicly available offshore and onshore datasets. We integrate high-resolution seismic reflection data from the offshore CASIE21 expedition with three previously published, lower-resolution onshore slab models (McCrory et al., 2012; Hayes et al., 2018; Bloch et al., 2023) to construct a unified Moho surface. This synthesis produces six alternative Moho geometries, enabling flexibility for studies that require varying structural assumptions. The accompanying open-source workflow offers a transparent and adaptable approach for combining heterogeneous datasets. In areas lacking direct constraints, Moho depths were estimated through interpolation from adjacent regions. The resulting models provide a valuable foundation for analyzing along-strike variations in slab structure and their implications for Cascadia geodynamics.
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