Horizontal deformation in the Cascadia subduction zone as derived from serendipitous geodetic data (EN)

Matsikari, T (EN)

Snay, RA (EN)

Data from recent Global Positioning System (GPS) surveys are combined with triangulation/trilateration data to estimate horizontal shear-strain rates for two regions in the Cascadia subduction zone. Near Bellingham, Washington, we estimate that the maximum horizontal shear rate (gamma) equals 0.116 +/- 0.089-mu-rad/yr and the direction of maximum horizontal contraction (theta) orients N71-degrees-E +/- 21-degrees for data spanning the 1905-1985 interval. The corresponding estimates for a region near Portland, Oregon, are 0.057 +/- 0.027-mu-rad/yr and N95-degrees-E +/- 14-degrees for data spanning the 1881-1988 interval. These estimates are consistent with estimates from independent geodetic data in the area. Moreover, the estimates for theta are consistent with the N68-degrees-E direction of ongoing convergence between the Juan de Fuca plate and the North American plate as predicted by the NUVEL-1 plate motion model. This consistency between theta-estimates and the direction of plate convergence supports the argument for the possibility of a great subduction earthquake occurring in the Cascadia subduction zone. The low shear rates, however, imply that the recurrence interval between such earthquakes would be several centuries long. (EN)

journalArticle (EN)

geodetic data (EN)

subduction (EN)

recurrence interval (EN)

shear strain (EN)

deformation (EN)

earthquake (EN)

Geochemistry & Geophysics (EN)

Global Positioning System (EN)

Pacific, Cascadia Subduction Zone (EN)

Εθνικό Μετσόβιο Πολυτεχνείο

Ψηφιακό Αποθετήριο της Κεντρικής Βιβλιοθήκης του ΕΜΠ | Dspace@NTUA

Κεντρική Βιβλιοθήκη Ε.Μ.Π.

Ιδρυματικό Αποθετήριο

Δημοσιεύσεις μελών Δ.Ε.Π. σε περιοδικά

Tectonophysics (EN)

Αγγλική γλώσσα

1991 (EN)

http://hdl.handle.net/123456789/10453

67 (EN)

59 (EN)

1-2 (EN)

ISI:A1991FY74600005 (EN)

194 (EN)

0040-1951 (EN)

ELSEVIER SCIENCE BV (EN)