Plate Tectonic Contest in North Greenland: ABSTRACT

Abstract

North Greenland is characterized by excellent exposure, lack of strong deformation, and great lateral extent of depositional systems. It is thus a unique region for the study of tectonics and sedimentation in successive plate tectonic configurations covering a period of more than 600 m.y. During late Precambrian to early Paleozoic times the major east-west-trending Franklinian carbonate shelf-clastic deep-water basin developed. The basin probably reached an incipient or narrow ocean stage. At its eastern end it was truncated by the north-south-trending continental margin of the contemporaneous Iapetus Ocean. The progressive closure of Iapetus resulted in Cambrian-Early Ordovician peripheral bulge upward of the eastern part of the Franklinian shelf. Erosion products from the shelf were resedimented into the Franklinian basin. The remainder of the Ordovician was tectonically quiet with starved basin sedimentation. The eastern part of the Franklinian shelf foundered rapidly in the Llandoverian, probably due to loading by Caledonian nappes advancing from the east during th progressive closure of Iapetus. From the start of the Silurian, the Franklinian basin began to receive enormous quantities of siliciclastic deep-sea fan turbidites (> 1 million km3) from eastern source areas in the uplifted Iapetus collision zone. A major west-verging thrust belt appears to mark the final phase of Iapetus collision. The Devonian saw the closure of the narrow Franklinian basin by north-south compression. Late Paleozoic, Mesozoic, and Cenozoic basin formation was mainly of transtensional nature in a northwest-southeast-trending zone between Greenland and Svalbard. Eventually, normal continental margin sedimentation started with the onset of spreading in the Paleogene. End_of_Article - Last_Page 309------------