Publication Date:
2016-11-19
Description:
Large impacts provide a mechanism for resurfacing planets through mixing near-surface
rocks with deeper material. Central peaks are formed from the dynamic uplift of rocks
during crater formation. As crater size increases, central peaks transition to peak rings.
Without samples, debate surrounds the mechanics of peak-ring formation and their depth
of origin. Chicxulub is the only known impact structure on Earth with an unequivocal
peak ring, but it is buried and only accessible through drilling. Expedition 364 sampled the
Chicxulub peak ring, which we found was formed from uplifted, fractured, shocked, felsic
basement rocks. The peak-ring rocks are cross-cut by dikes and shear zones and have
an unusually low density and seismic velocity. Large impacts therefore generate vertical
fluxes and increase porosity in planetary crust.
Repository Name:
EPIC Alfred Wegener Institut
Type:
Article
,
isiRev
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