An analysis of ridge axis gravity roughness and spreading rate
Fast and slow spreading ridges have radically different morphologic and gravimetric characteristics. In this study, altimeter measurements from the Geosat Exact Repeat Mission are used to investigate spreading rate dependence of the ridge axis gravity field. Gravity roughness provides an estimate of...
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1992
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ftnasantrs:oai:casi.ntrs.nasa.gov:19920045494 2023-05-15T14:03:21+02:00 An analysis of ridge axis gravity roughness and spreading rate Small, Christopher Sandwell, David T. Unclassified, Unlimited, Publicly available Mar 10, 1992 http://ntrs.nasa.gov/search.jsp?R=19920045494 unknown http://ntrs.nasa.gov/search.jsp?R=19920045494 Accession ID: 92A28118 Copyright Other Sources 48 Journal of Geophysical Research; 97; B3, M; 3235-324 1992 ftnasantrs 2012-02-15T19:30:22Z Fast and slow spreading ridges have radically different morphologic and gravimetric characteristics. In this study, altimeter measurements from the Geosat Exact Repeat Mission are used to investigate spreading rate dependence of the ridge axis gravity field. Gravity roughness provides an estimate of the amplitude of the gravity anomaly and is robust to small errors in the location of the ridge axis. Gravity roughness as a weighted root mean square of the vertical deflection at 438 ridge crossings on the mid-ocean ridge system is computed. Ridge axis gravity anomalies show a decrease in amplitude with increasing spreading rate up to an intermediate rate of about 60-80 mm/yr and almost no change at higher rates; overall the roughness decreases by a factor of 10 between the lowest and highest rates. In addition to the amplitude decrease, the range of roughness values observed at a given spreading rate shows a similar order of magnitude decrease with transition between 60 and 80 mm/yr. The transition of ridge axis gravity is most apparent at three relatively unexplored locations on the Southeast Indian Ridge and the Pacific-Antarctic Rise; on these intermediate rate ridges the transition occurs abruptly across transform faults. Other/Unknown Material Antarc* Antarctic NASA Technical Reports Server (NTRS) Antarctic Indian Pacific Southeast Indian Ridge ENVELOPE(110.000,110.000,-50.000,-50.000) |
institution |
Open Polar |
collection |
NASA Technical Reports Server (NTRS) |
op_collection_id |
ftnasantrs |
language |
unknown |
topic |
48 |
spellingShingle |
48 Small, Christopher Sandwell, David T. An analysis of ridge axis gravity roughness and spreading rate |
topic_facet |
48 |
description |
Fast and slow spreading ridges have radically different morphologic and gravimetric characteristics. In this study, altimeter measurements from the Geosat Exact Repeat Mission are used to investigate spreading rate dependence of the ridge axis gravity field. Gravity roughness provides an estimate of the amplitude of the gravity anomaly and is robust to small errors in the location of the ridge axis. Gravity roughness as a weighted root mean square of the vertical deflection at 438 ridge crossings on the mid-ocean ridge system is computed. Ridge axis gravity anomalies show a decrease in amplitude with increasing spreading rate up to an intermediate rate of about 60-80 mm/yr and almost no change at higher rates; overall the roughness decreases by a factor of 10 between the lowest and highest rates. In addition to the amplitude decrease, the range of roughness values observed at a given spreading rate shows a similar order of magnitude decrease with transition between 60 and 80 mm/yr. The transition of ridge axis gravity is most apparent at three relatively unexplored locations on the Southeast Indian Ridge and the Pacific-Antarctic Rise; on these intermediate rate ridges the transition occurs abruptly across transform faults. |
format |
Other/Unknown Material |
author |
Small, Christopher Sandwell, David T. |
author_facet |
Small, Christopher Sandwell, David T. |
author_sort |
Small, Christopher |
title |
An analysis of ridge axis gravity roughness and spreading rate |
title_short |
An analysis of ridge axis gravity roughness and spreading rate |
title_full |
An analysis of ridge axis gravity roughness and spreading rate |
title_fullStr |
An analysis of ridge axis gravity roughness and spreading rate |
title_full_unstemmed |
An analysis of ridge axis gravity roughness and spreading rate |
title_sort |
analysis of ridge axis gravity roughness and spreading rate |
publishDate |
1992 |
url |
http://ntrs.nasa.gov/search.jsp?R=19920045494 |
op_coverage |
Unclassified, Unlimited, Publicly available |
long_lat |
ENVELOPE(110.000,110.000,-50.000,-50.000) |
geographic |
Antarctic Indian Pacific Southeast Indian Ridge |
geographic_facet |
Antarctic Indian Pacific Southeast Indian Ridge |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
Other Sources |
op_relation |
http://ntrs.nasa.gov/search.jsp?R=19920045494 Accession ID: 92A28118 |
op_rights |
Copyright |
_version_ |
1766273978236665856 |