B. Mercier de Lépinay, F. Michaud, T. Calmus, J. Bourgois, G. Poupeau, P. Saint Marc, The NAUTIMATE team; Large Neogene subsidence event along the Middle America Trench off Mexico (18°N–19°N): Evidence from submersible observations. Geology ; 25 (5): 387–390. doi: https://doi.org/10.1130/0091-7613(1997)025<0387:LNSEAT>2.3.CO;2
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Exposures of pre-Eocene plutonic rocks located along the inner slope of the Middle America Trench were sampled during deep-sea dives off Manzanillo (lat 18°N–19°N) at depths ranging from 3950 m to 2823 m. Fission-track data show a rapid cooling of these plutonic rocks during the Paleocene. A subaerial unconformity indicates that the plutonic rocks were exposed after Paleocene time. The presence of upper middle bathyal upper Miocene–lower Pliocene marine sediments above the unconformity documents a Neogene subsidence event at a mean rate of 0.35 mm/yr. This subsidence indicates subduction erosion along this segment of the margin.