Yumul Jr., Graciano P. Apex Mining Company Inc.
Dimalanta, Carla B. University of the Philippines
Salapare, Ricky C. GHD
Queaño, Karlo L. Ateneo de Manila University
Faustino-Eslava, Decibel V. University of the Philippines
Marquez, Edanjarlo J. University of the Philippines
Ramos, Noelynna T. University of the Philippines
Payot, Betchaida D. University of the Philippines
Guotana, Juan Miguel R. Kanazawa University
Gabo-Ratio, Jillian Aira S. University of the Philippines
Armada, Leo T. University of the Philippines
Padrones, Jenielyn T. University of the Philippines
Suzuki, Shigeyuki Okayama University
New radiolarian ages show that the island arc-related Acoje block of the Zambales Ophiolite Complex is possibly of Late Jurassic to Early Cretaceous age. Radiometric dating of its plutonic and volcanic-hypabyssal rocks yielded middle Eocene ages. On the other hand, the paleontological dating of the sedimentary carapace of the transitional mid-ocean ridge – island arc affiliated Coto block of the ophiolite complex, together with isotopic age datings of its dikes and mafic cumulate rocks, also yielded Eocene ages. This offers the possibility that the Zambales Ophiolite Complex could have: (1) evolved from a Mesozoic arc (Acoje block) that split to form a Cenozoic back-arc basin (Coto block), (2) through faulting, structurally juxtaposed a Mesozoic oceanic crust with a younger Cenozoic lithospheric fragment or (3) through the interplay of slab rollback, slab break-off and, at a later time, collision with a microcontinent fragment, caused the formation of an island arc-related ophiolite block (Acoje) that migrated trench-ward resulting into the generation of a back-arc basin (Coto block) with a limited subduction signature. This Meso-Cenozoic ophiolite complex is compared with the other oceanic lithosphere fragments along the western seaboard of the Philippines in the context of their evolution in terms of their recognized environments of generation.
China University of Geosciences (Beijing)|Peking University|Elsevier
This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
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