GRAVITY FIELDS OVER MIDOCEAN RIDGES FROM GEOSAT GM DATA - VARIATIONS AS A FUNCTION OF SPREADING RATE

• Published in: Geophysical Research Letters
• Main Authors: Owens, R, Parsons, B
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2016
• Subjects: Antarctic; Indian; Pacific; Southeast Indian Ridge; Antarc*
• Online Access: https://doi.org/10.1029/94GL02667; https://ora.ox.ac.uk/objects/uuid:c3a00ff4-607a-437e-8713-66f351060ae1

Mean gravity profiles have been obtained from gravity fields constructed using Geosat Geodetic Mission altimeter data for a number of areas over mid-ocean ridges. For spreading rates larger than about 60-65 mm/yr, an axial gravity high is observed with an almost constant amplitude (~12 mgal) that narrows as the spreading rate increases. For spreading rates lower than this, an axial gravity low is observed whose amplitude decreases rapidly with spreading rate while the width reduces only slowly. The disappearance of a median valley occurs abruptly on any one ridge, but occurs at slightly different spreading rates on the Southeast Indian Ridge (68 mm/yr) and the Pacific-Antarctic Ridge (60 mm/yr). -Authors