Constraints on the evolution of the East Greenland Margin: evidence from detrital apatite in offshore sediments

• Main Authors: Clift, P.D., Carter, Andrew, Hurford, A.J.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Geological Society of America 1996
• Subjects: Earth and Planetary Sciences; Greenland; East Greenland; Iceland
• Online Access: https://eprints.bbk.ac.uk/id/eprint/28458/; https://doi.org/10.1130/0091-7613(1996)024<1013:COTEOT>2.3.CO;2

We test a new approach to understanding the tectonic evolution of passive margins by using fission-track analysis on detrital apatites from sediments deposited offshore East Greenland. These apatites have not undergone postdepositional track annealing and therefore reflect provenance. The apatites preserve a component of the source rocks' thermal history that otherwise may not be retained within the present-day outcrop. Fission-track–derived denudational histories from samples at Ocean Drilling Program drill sites offshore East Greenland at lat 63°N are compared with data from the onshore Singertat Complex. Previous apatite fission-track studies and geomorphic mapping of the East Greenland coast have shown that locally up to 6 km of denudation may have occurred, implying significant tectonic or magmatic activity starting as much as 30 m.y. after breakup at 56 Ma. In contrast, apatite fission-track data presented here record <2 km of Cenozoic denudation in southeast Greenland, probably driven by magmatic underplating at the time of breakup. Large-magnitude, postrift denudation of East Greenland is restricted to the area around Kangerdlugssuaq (68°N). The timing (<40–50 Ma) and magnitude are in accord with revised plume track models suggesting that the Iceland plume crossed the margin here during the late Eocene.