Department of Geology and Geophysics, Building F05
University of Sydney, N.S.W. 2006
Australia
poster/oral: web page
We have created a digital age grid of the ocean floor with a grid node interval of 6 arc-minutes using a self-consistent set of global isochrons and associated plate reconstruction poles. The age at each grid node was determined by linear interpolation between adjacent isochrons in the direction of spreading. Ages for ocean floor between the oldest identified magnetic anomalies and continental crust were interpolated by estimating the ages of passive continental margin segments from geological data and published plate models.
We have constructed a grid with error estimates from each grid cell as a function of (1) the error of ocean floor ages identified from magnetic anomalies along ship tracks and the age of the corresponding grid cells in our age grid, (2) the distance of a given grid cell to the nearest magnetic anomaly identification, and (3) the gradient of the age grid, i.e. larger errors are associated with high age gradients at fracture zones or other age discontinuities. The gridded ages of the ocean floor are based on a gidital set of isochrons. The isochrons are based on a large number of marine magneitc anomaly data, satellite altimetry data, and a self-consistent plate model. http://www.usyd.edu.au/su/geosciences/geology/people/staff/dietmar/Agegrid/digit_isochrons.html Dietmar's home page