A
reappraisal of the stratigraphy, new regional kinematic analysis and
thermobarometric data allow a new interpretation of the metamorphic zoning and
tectonic structure of the Upper Eocene high-pressure metamorphic core complex of
northernNew Caledonia allow a
three steps evolution to be proposed:
1. subduction and understacking of previously thinned
continental crust elements;
2.
subduction blocking due to the crustal thickening; and
3. crustal thinning and extensional detachment during
the diapir-like uplift and unroofing of the eclogitic core.
Steps
2 and 3 may be partly contemporaneous. Such a model accounts for the
thermobarometric and radiochronologic data, and also for the weakness of
substratum deformation during the emplacement of the ophiolitic
nappe