On the west side of Luzon, the Sunda Plate subducts
eastward along a series of trenches, including the Manila Trench in the north, the smaller less well-developed Negros Trench in the central Philippines, and the Sulu and Cotabato trenches in the south (Cardwell et al.
The northern edge of the Panama arc merges without apparent tearing northward into the Caribbean slab that subducts
beneath northwest Colombia (Figure 4)
The Adriatic plate, which includes Venice, subducts
beneath the Apennines Mountains and causes the city and its environs to drop slightly in elevation," he said.
Geologists from the University of California, Berkeley, have proposed that a large area of upwelling hot rock has effectively lubricated the movement at the plate's boundary as it subducts
under the vast North American plate.
In general, it is accepted that in the Southern region, the Nazca plate continuously subducts
with a 30[degrees] dip angle down to about 300 km depth; while in the Central region, the plate subducts
with an initial 10[degrees] dip angle from the trench to the coastline, increasing to a 30[degrees] dip to a depth of 120 km, and then becoming almost horizontal up to distances of 500 km from the trench.
Seismic activity in this zone locates between isodepths of 80-160km within the Wadati-Benioff zone of Nazca plate, which subducts
along the Colombian northwest (Monsalve, 1998), and also along numerous crustal faults.