DIFFERENTIAL DENUDATION AND FLEXURAL ISOSTASY IN FORMATION OF RIFTED-MARGIN UPWARPS

被引:190
作者
GILCHRIST, AR
SUMMERFIELD, MA
机构
[1] UNIV EDINBURGH,DEPT GEOG,MACROGEOMORPHOL RES GRP,EDINBURGH EH8 9XP,SCOTLAND
[2] UNIV LIVERPOOL,DEPT EARTH SCI,LIVERPOOL L69 3BX,ENGLAND
关键词
D O I
10.1038/346739a0
中图分类号
O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];
学科分类号
07 ; 0710 ; 09 ;
摘要
MARGINAL upwarps are common features of rifted continental margins1,2, but tectonic models of the evolution of rifted margins have not adequately explained their form, or their persistence along some margins more than 100 Myr after continental rupture. Marginal upwarps not only significantly influence the geomorphological evolution of rifted margins and their adjacent continental interiors, but are also important in determining patterns of offshore sedimentation. Here we show that the contrast in denudation rates between the evolving coastal flanks of rifted margins and their interior hinterlands can promote significant marginal upwarps if the lithosphere responds flexurally to the resulting differential unloading2,3. Using data for the western margin of southern Africa, we demonstrate that upwarps of 600 m with respect to the adjacent continental interior can be generated by this process independently of the mechanics of rifting. © 1990 Nature Publishing Group.
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页码:739 / 742
页数:4
相关论文
共 31 条
[2]   THE TIMING OF UPLIFT, VOLCANISM, AND RIFTING PERIPHERAL TO THE RED-SEA - A CASE FOR PASSIVE RIFTING [J].
BOHANNON, RG ;
NAESER, CW ;
SCHMIDT, DL ;
ZIMMERMANN, RA .
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS, 1989, 94 (B2) :1683-1701
[3]  
BRAUN J, 1989, GEOLOGY, V17, P760, DOI 10.1130/0091-7613(1989)017<0760:APEOTR>2.3.CO
[4]  
2
[5]  
BROWN RW, IN PRESS NUCL TRACKS
[6]  
BUCK WR, 1986, EARTH PLANET SC LETT, V77, P362, DOI 10.1016/0012-821X(86)90146-9
[7]   THERMAL CONSEQUENCES OF LITHOSPHERIC EXTENSION - PURE AND SIMPLE [J].
BUCK, WR ;
MARTINEZ, F ;
STECKLER, MS ;
COCHRAN, JR .
TECTONICS, 1988, 7 (02) :213-234
[8]   THE ROLE OF MANTLE PLUMES IN THE DEVELOPMENT OF CONTINENTAL DRAINAGE PATTERNS [J].
COX, KG .
NATURE, 1989, 342 (6252) :873-877
[9]  
CULLING W. E. H., 1965, Journal of Geology, V73, P230
[10]   EFFECTIVE ELASTIC PLATE THICKNESS BENEATH THE EAST-AFRICAN AND AFAR PLATEAUS AND DYNAMIC COMPENSATION OF THE UPLIFTS [J].
EBINGER, CJ ;
BECHTEL, TD ;
FORSYTH, DW ;
BOWIN, CO .
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH AND PLANETS, 1989, 94 (B3) :2883-2901