Denudation rates for the southern Drakensberg escarpment, SE Africa, derived from in-situ-produced cosmogenic 36Cl:: initial results

被引：98

作者：

Fleming, A ^{[1
]}

Summerfield, MA

Stone, JO

Fifield, LK

Cresswell, RG

机构：

[1] Univ Edinburgh, Dept Geog, Edinburgh EX9 8XP, Midlothian, Scotland

[2] Australian Natl Univ, Res Sch Earth Sci, Canberra, ACT 0200, Australia

[3] Australian Natl Univ, Res Sch Phys Sci & Engn, Canberra, ACT 0200, Australia

来源：

JOURNAL OF THE GEOLOGICAL SOCIETY | 1999年 / 156卷

关键词：

SE Africa; cosmogenic isotopes; denudation; landscapes; scarps;

D O I：

10.1144/gsjgs.156.2.0209

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

Cosmogenic Cl-36 concentrations in basalt samples from the Drakensberg escarpment on the SE African passive margin give quantitative estimates of denudation and scarp retreat rates. Over the 10(4)-10(6) year timespan addressed by these data, the calculated escarpment retreat rate has been 50-95m Ma(-1) and the average summit denudation rate 6m Ma(-1). The scarp retreat rate is an order of magnitude less than previously suggested. The rate of summit lowering is sufficient to prevent the long-term intact survival of erosion cycle surfaces formed in the Mesozoic that were previously inferred for this region.

引用

页码：209 / 212

页数：4

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