Principle of Uniformitarianism: Criteria for Paleotectonic Reconstructions
by the Example of the Kurile-Kamchatka Region

G.P. Avdeiko1, D.P. Saveliev2, S.V. Popruzhenko2, A.A. Palueva1

1Institute of Volcanic Geology and Geochemistry FED RAS, Petropavlovsk-Kamchatsky, 683006
2Natural Resources Department of the Kamchatka region and Koryak autonomous district,
Ministry of Natural Resources of Russia, Petropavlovsk-Kamchatsky, 683006

Analysis of the tectonic structure and volcanism of the present-day subduction zones and comparison of these results with similar characteristics and stages of tectonic history and volcanic activity of the Kurile-Kamchatka region has been made. It is shown that the present-day structure of the Kurile-Kamchatka region is determined by the three different-age volcanic belts, which are volcanic arcs, located above the subduction zones. These subduction zones and arcs discretely rejuvenate and shift towards the Pacific Ocean. These data provide a basis for clarifying the criteria for paleotectonic reconstructions. The most reliable criteria for the subduction stage of development are volcanogenic formations of island-arc (subductional) geochemical type. In certain tectonic conditions occurence of rocks of the “intraplate” geochemical type is possible alongside with predominant island-arc type rocks. The other petrological, geochemical or formational criteria may only play a subsidiary role for more precise definition of relative spatial location of the frontal (tectonic) arc, deep-sea trench, pre-arc and back-arc basins of sedimentation. The revealed geodynamic parameters allow us to determine direction of the subduction and to evaluate qualitatively the angle of subduction by the width of the volcanic arc. When reconstructing the tectonic history it should be taken into account that each subduction zone has its own basement, different from the one of the neighbouring older and younger arcs.

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