Publikationsdatum:
2024-01-09
Beschreibung:
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.
Schlagwort(e):
152-914B; 152-915A; 152-918D; Age, dated; Age, dated material; Age, dated standard deviation; Age, maximum/old; Age, standard deviation; DRILL; Drilling/drill rig; DSDP/ODP/IODP sample designation; Event label; Fission-track length, mean; Fission-track length, mean, standard deviation; Fission-tracks; Fission-tracks, density, counted in stan; Fission-tracks, induced; Fission-tracks, induced, density; Fission-tracks, spontaneous; Fission-tracks, spontaneous, density; Greenland Sea; Joides Resolution; Leg152; Number of observations; Number of tests; Ocean Drilling Program; ODP; Sample code/label; Standard deviation
Materialart:
Dataset
Format:
text/tab-separated-values, 134 data points
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