Geomorphic development of the escarpment of the Eritrean margin, southern Red Sea from combined apatite fission-track and (U Th)/He thermochronometry

Details Geomorphic development of the escarpment of the Eritrean margin, southern Red Sea from combined apatite fission-track and (U Th)/He thermochronometry Geomorphic development of the escarpment of the Eritrean margin, southern Red Sea from combined apatite fission-track and (U Th)/He thermochronometry

Feb 2005

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005e%26psl.231...97b&link_type=abstract

Earth and Planetary Science Letters, Volume 231, Issue 1-2, p. 97-110.

Physics

11

Scientific paper

Apatite (U Th)/He and fission-track thermochronometers are combined to constrain models of denudation and escarpment development of the high elevation Eritrean margin along the southern Red Sea. (U Th)/He ages have been determined for apatites from two coast-perpendicular transects that were previously used for apatite fission-track analysis [E. Abbate, M.L. Balestrieri, G. Bigazzi, Morphostructural development of the Eritrean rift flank (southern Red Sea) inferred from apatite fission track analysis, J. Geophys. Res., 107, B11, doi: 10.1029/2001JB001009, (2002)]. In central Eritrea near Asmara, He ages increase from c. 7 Ma at the coast to 152 Ma on the plateau along a transect. Further south, He ages from the margin border to the base of the escarpment span a narrower range (7 to 12 Ma). One sample from the top of a marginal high (2950 m) yields older ages (22 43 Ma). Forward modeling suggests that the He age distribution across the margin should allow scarp retreat and downwearing mechanisms to be distinguished in the case of a margin formed in the last twenty million years. The distribution of He ages suggests that the escarpment evolved by downwearing and that post-break up erosion of the escarpment was facilitated by in situ excavation rather than parallel retreat. This implies the existence of an inland drainage divide located seaward of the present day escarpment rim. We envisage that the inland divide formed during or immediately after continent break up, and that the eastern marginal belt represents a remnant of the apex structure. The short distance between the eastern marginal belt and the rim (c. 10 km) represents the total retreat of the escarpment. Comparison of the measured He ages from the coastal plain with those predicted from forward modelling indicates that the main phase of post-break up erosion started at about 15 Ma, closer to the initiation of seafloor spreading in the Red Sea than was thought previously.

Affiliated with

Also associated with

No associations

Rating

Geomorphic development of the escarpment of the Eritrean margin, southern Red Sea from combined apatite fission-track and (U Th)/He thermochronometry does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Geomorphic development of the escarpment of the Eritrean margin, southern Red Sea from combined apatite fission-track and (U Th)/He thermochronometry, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Geomorphic development of the escarpment of the Eritrean margin, southern Red Sea from combined apatite fission-track and (U Th)/He thermochronometry will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1358367