Chixoy-Polochic Fault
The Chixoy-Polochic Fault, also known as Cuilco-Chixoy-Polochic Fault, is a major fault zone in Guatemala and southwestern Mexico. It runs in a light arc from the east coast of Guatemala to Chiapas, following the deep valleys of the Polochic River, Chixoy River and Cuilco River.[1]
Extent and total displacement
The Chixoy-Polochic Fault runs largely parallel to the Motagua Fault situated some 80 km to its south. Both fault zones are onshore extensions of the Bartlett Deep, or Cayman Trench of the Caribbean Sea, which marks the tectonic boundary between the Caribbean Plate and the North American Plate.[1]
The Chixoy-Polochic fault has total displacement of 125 km, well constrained by the offset of Paleocene or Eocene laramide folds and thrusts [2].
Seismicity
While recent seismic activity is more prominent in the Motagua fault, some studies suggest the Chixoy-Polochic Fault is still capable of producing major earthquakes. The magnitude of 7.5–7.8 Mw 1816 Guatemala earthquake of western Guatemala has been ascribed to the Polochic Fault [3], although this has been disputed [4][5].
References
- ^ a b Ortega-Gutiérrez, Fernando; et al. (2007). "The Maya-Chortís Boundary: A Tectonostratigraphic Approach" (PDF). International Geology Review. 49 (11): 996–1024. doi:10.2747/0020-6814.49.11.996.
- ^ Burkart, Burke (1978-06-01). "Offset across the Polochic fault of Guatemala and Chiapas, Mexico". Geology. 6 (6). doi:10.1130/0091-7613(1978)6<328:OATPFO>2.0.CO;2. ISSN 0091-7613.
- ^ White, Randall A. "The Guatemala earthquake of 1816 on the Chixoy-Polochic fault". Bulletin of the Seismological Society of America. 75 (2). Seismological Society of America: 455–473.
- ^ Brocard, Gilles; Anselmetti, Flavio S.; Teyssier, Christian (2016-11-15). "Guatemala paleoseismicity: from Late Classic Maya collapse to recent fault creep". Scientific Reports. 6 (1). doi:10.1038/srep36976. ISSN 2045-2322.
- ^ Guzmán-Speziale, Marco (2010-12-01). "Beyond the Motagua and Polochic faults: Active strike-slip faulting along the Western North America–Caribbean plate boundary zone". Tectonophysics. 496: 17–27. doi:10.1016/j.tecto.2010.10.002.