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Vol. 87 Supp.
ACTA GEOLOGICA SINICA (English Edition)
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June 2013
Tim KUSKY, Windley Brian, Safonova Inna, Wakita Koji, Wakabayashi John, Polat Ali and Santosh Madha, 2013. Recognition of
Ocean Plate Stratigraphy in Accretionary Orogens Through Earth History: A Record of 3.8 Billion Years of Sea Floor Spreading,
Subduction, and Accretion. Acta Geologica Sinica (English Edition), 87(supp.): 307.
Recognition of Ocean Plate Stratigraphy in Accretionary Orogens Through
Earth History: A Record of 3.8 Billion Years of Sea Floor Spreading,
Subduction, and Accretion
Tim KUSKY1,*, Windley Brian2, Safonova Inna3, Wakita Koji4, Wakabayashi John5,
Polat Ali6 and Santosh Madha7
1 China University of Geosciences Wuhan
2 University of Leicester, UK
3 Institute of Geology and Mineralogy, SB RAS
4 Geological Survey of Japan
5 California State University, Fresno
arc basalts, oceanic plateau basalts, ocean island basalts,
and boninites, with extremely rare komatiites. This
demonstrates that sea-floor spreading, lateral movement of
oceanic plates with accompanying sedimentation over the
oceanic substratum, and accretion at convergent margins
has been a major Earth process since at least 3.8 Ga ago.
There have been some secular changes in the rock types in
OPS, such as changes in carbonates and radiolarian cherts
whose sources were in the biota in existence in
Phanerozoic times but absent in the Precambrian, but
overall, there have been few changes in the style of OPS
accretion with time. Komatiites and banded iron
formations occur predominantly in Archean orogenic
belts, reflecting higher mantle temperatures and less oxic
seawater composition, respectively, before 2.5 Ga. This is
clear documentation that plate tectonics, including the
lateral movement of oceanic lithosphere, has been a major
heat loss mechanism on Earth since the early Precambrian.
Ocean plate stratigraphy (OPS) is a term used to
describe the sequence of sedimentary and volcanic rocks
deposited on oceanic crust substratum from the time it
forms at a spreading center, to the time it is incorporated
into an accretionary prism at a convergent margin. In this
study, we review the major geological characteristics of
relict Cenozoic to early Archean oceanic crust and OPS
persevered in Alaska, Japan, California (Franciscan
Complex), Central Asia, British Isles, Canada (Slave
Province), Australia (Pilbara craton), and Greenland (Isua
and Ivisaartoq belts). An assessment of OPS in
accretionary orogens spanning the duration of Earth’s rock
record shows remarkable similarities between OPS of all
ages in terms of structural style, major rock components,
sequence of accretion, and trace element geochemical
signatures. Volcanic rocks preserved in the orogenic belts
are characterized predominantly by oceanic island arc
basalts, island arc picrites, mid-ocean ridge basalts, back-
* Corresponding author. E-mail: [email protected]
307