Thread: Technical Session: Structure and Geodynamics of the Caribbean Plate Boundaries

Started: 2018-01-19 01:13:31
Last activity: 2018-01-19 01:13:31
Topics: SSA Meetings
SSA Abstracts are due on January 24: We encourage submissions for the Technical Session:

Structure and Geodynamics of the Caribbean Plate Boundaries

The Caribbean plate (CAR) is unusual for a number of reasons. The region’s history includes numerous destructive large magnitude earthquakes and tsunamis. An intermediate sized plate (3.3x106 km2), CAR is surrounded on its north, east and south by the much larger American plates, but since much of CAR is a large igneous province (LIP), its buoyancy makes it difficult to subduct. As a consequence, it is girdled by inward directed subduction zones; the Antilles on the east, the Puerto Rico Trench in the northeast and the Central American Trench on the west. Further, the large El Pilar-San Sebastian strike-slip system along northeastern South America (SA) connects the southern Antilles trench to the Southern Caribbean Deformed Belt and a poorly defined subduction zone in northwestern SA, at which CAR subducts beneath northern Colombia and western Venezuela. The flat CAR subduction has created the Merida Andes, Perija and Santa Marta uplifts. Since the SA plate is subducting beneath CAR at the southern Antilles subduction zone and CAR is subducting southeastward beneath western SA, the two plates are subducting beneath one another. The number and volume of plates descending beneath CAR as imaged in different tomography studies (e.g., Bezada et al, JGR, 2010 and Van Benthem et al, JGR, 2013) create interesting space problems in the upper mantle beneath CAR and its neighbors, influencing upper mantle flow.
In north and northwestern CAR a complex series of strike slip and oblique slip faults extend from Puerto Rico across and around Hispaniola to join with the strike slip faults of the Cayman trough. These include what may be incipient northward subduction of CAR along the Muertos trough south of Hispaniola and Puerto Rico.
The plate boundaries around Panama are complicated and include what appears to be incipient CAR subduction just east of the Panama arc and the northeastern boundary of the recently identified Coiba and Malpelo plates (Zhang et al., GRL, 2017), bounded by the Panama arc, Cocos, Nazca and SA.
This diversity of tectonic boundaries provides an unusually rich source for seismicity and tsunamigenic earthquakes. Regional seismicity and GPS velocities suggest that a number of small tectonic blocks, moving quasi-independently and deforming internally, are caught in the boundary zones between CAR and the surrounding plates.
We invite contributions on any aspect of seismic structure, plate structure, deformation, seismicity and geodynamics in and around the Caribbean.
Invited Speakers: Max Bezada, Rob Govers, German Prieto, Kate Rychert
Session Conveners
Alan Levander, Rice University, <alan<at>>
Fenglin Niu, Rice University, <niu<at>>

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