HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) References Citation Map Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by LISOWSKI, M. Articles by THATCHER, W. Search for Related Content GeoRef GeoRef Citation

Geodetic determination of horizontal deformation associated with the Guatemala earthquake of 4 February 1976

U.S. GEOLOGICAL SURVEY, 345 MIDDLEFIELD ROAD, MENLO PARK, CALIFORNIA 94025

Abstract

A 15-station geodetic control network extending 10 km north and 40 km south of the Motagua fault in Guatemala was reobserved 2 yr after the 4 February 1976 M_S = 7.5 earthquake. The initial first-order triangulation was observed in two parts: the Guatemala-Honduras border arc completed in 1935 and the Motagua valley arc completed in 1953. Both angles and distances were observed in the 1978 resurvey. The angle changes between the combined 1935 to 1953 survey and the 1978 resurvey were used to calculate earthquake-related fault slip on two dislocation models of the rupture surface. Left-lateral slip of 1.3 ± 0.1 m is calculated for a model fault with constant displacement from 0 to 15 km. For a model fault divided into three successively deeper sections, the calculated left-lateral slip is 0.8 ± 0.1 m near the surface, increasing to 2.1 ± 0.5 m in the intermediate 5- to 15-km section, and is undetermined at greater depths. Both models are consistent with the 0.9 to 1.1 m of accumulated slip and afterslip observed near the network by Bucknam et al. (1978). The second model is in better agreement with the 2 m of slip derived by Kanamori and Stewart (1978) from a long-period seismic surface wave estimate of the seismic moment.

This article has been cited by other articles:

				C. J. YOUNG, T. LAY, and C. S. LYNNES Rupture of the 4 February 1976 Guatemalan earthquake Bulletin of the Seismological Society of America, June 1, 1989; 79(3): 670 - 689. [Abstract] [PDF]