On a different test, with a set with 87,005 points which corresponded approximately to 1,392 km of trace length, Marchal's algorithm (either version) took 20 s in the matching process, for GEMMA it took approximately one hour and 79 s for M-GEMMA.
The horizontal and vertical axes indicate the geographic latitude of the footprint at 110 km altitude traced from satellite position along the geomagnetic field and period, respectively.
For the first experiment, we initially built a base map with YouTrace with 225 km of traces in the area of Coimbra, originating 730 intersections and 15,901 links (1,264 super-links).
Similar features of the crustal structure observed in Y = -16 km could be traced to the cross section of Y = -8 km.
A 76-km-long surface trace was found, and the maximum surface displacement was 7 m left laterally and 6 m vertically (Matsuda 1974).
These two stations were located within 2 km of the surface trace of the Futagawa fault.
Fig. 6 As in Fig. 5 but for events located within 5 km from the surface trace of Atotsugawa fault.
Note that the solutions with epicenters located within 5 km from the surface trace of the Atotsugawa fault are not plotted.
Most of the recalculated epicenters lie within 2 km of the surface trace of the MMF (Fig. 7a), although some of them are 3 10 km west of those of the KOERI earthquake catalogue.
One puzzling feature of the earthquake is that high angle surface rupture is observed over more than 200 km of the fault trace (Zhang et al., 2008), but teleseismic models typically assume low angle faults (about 30 degree) with a rupture length of up to 300 km (Hayes and Ji, 2008; Nishimura and Yagi, 2008).
