[1] We simulate jumps of ocean spreading centers with axial high topography using elastoplastic thin plate flexure models. Processes considered include ridge abandonment, the breaking of a stressed plate on the ridge flank, and renewed spreading at the site of this break. We compare model results to topography at the East Pacific Rise between 15 250N and 16 N, where there is strong evidence of ...

Sparse and non-availability of high resolution geophysical data hindered the delineation of accurate morphology, structural configuration, tectonism and spreading history of Carlsberg Ridge (CR) and Central Indian Ridges (CIR) in the Indian Ocean between Owen fracture zone at about 10N, and the Rodriguez Triple Junction at ~25S. Analysis of available multibeam bathymetry, magnetic, gravity, sea...

[1] The Mid-Atlantic Ridge around the Fifteen-Twenty Fracture Zone is unique in that outcrops of lower crust and mantle rocks are extensive on both flanks of the axial valley walls over an unusually long distance along-axis, indicating a high ratio of tectonic to magmatic extension. On the basis of newly collected multibeam bathymetry, magnetic, and gravity data, we investigate crustal evolutio...

THE existence of a negative gravity anomaly of amplitude about 20 mgal below northern Skye was first pointed out by Tuson1, who interpreted it as being due to a sedimentary basin bounded at its NE margin by a large NW-SE fault. Our recent geophysical work confirms the existence of this basin, defines its margins more accurately, and provides evidence for the age of the infilling. Fig. 1 shows t...

[1] We show that the two-dimensional coherence between topography and Bouguer gravity is anisotropic throughout most of the Canadian Shield, excepted Hudson Bay Basin. We interpret the axis of maximum coherence as the direction where the lithosphere is weakest. In the southeastern Shield and the Appalachians, the azimuthally averaged coherence cannot be fitted by the thin elastic plate model. I...

Spreading segments of the Mid-Atlantic Ridge show negative bull's-eye anomalies in the mantle Bouguer gravity field. Seismic refraction results from 33 degrees S indicate that these anomalies can be accounted for by variations in crustal thickness along a segment. The crust is thicker in the center and thinner at the end of the spreading segment, and these changes are attributable to variations...

In magma-rich continental rifts, extension is commonly localized as dike injection in discrete magmatic segments which appear from surface geology to mimic the along-axis segmentation of ocean ridges. However, subsurface morphology these zones magma unclear, and whether at what depth range they remain with subvolcanic plumbing systems not fully understood. addition, relationship between tectoni...

SUMMARY The complex Moho topography beneath the northwestern Andes is result of multiple geodynamic processes during Cenozoic. To contribute to our understanding depth distribution this region, we inverted gravity data from two widely used satellite-derived sets (EGM2008 and EIGEN-6C4) one regional airborne Bouguer anomaly map (ANH2010). Their inversion allowed choosing ANH2010, based on lower ...