David C. Jefferson

TL;DR: This work determines precise GPS satellite positions and clock corrections from a globally distributed network of GPS receivers, and analysis of data from hundreds to thousands of sites every day with 40-Mflop computers yields results comparable in quality to the simultaneous analysis of all data.

TL;DR: In this article, the combined geodetic moment for the Landers and Big Bear earthquakes was analyzed and shown to be dominantly symmetric and the rupture extended farther south on the Johnson Valley fault than has been mapped on the basis of ground offsets.

TL;DR: In this paper, the authors apply two different inverse methods to understand the source of the seismic strain in NW Costa Rica and compare fault-locking models derived using a singular value decomposition inversion with that of a simulated annealing global optimization approach.

TL;DR: Geodetic measurements using the Global Positioning System and other techniques show north-south shortening near Los Angeles to be fastest across the northern part of the metropolitan area, where an ESE-striking, 5- to 40-km-wide belt lying to the south of San Gabriel Mountains and to the north of downtown and West Los Angeles is shortening at 5 mm/yr as mentioned in this paper.

TL;DR: In this paper, a linear fit to the full span of data shows agreement between the two frames at the level of 1 −1 and 0 −0.1 −ppb/year.