Altimeter-bearing satellites produce images of the earth's gravity field in unprecedented detail. The images reveal crustal architecture in scale intermediate between lithosphere plates and local fault blocks. Geoidal images provide a preview of the architecture of remote regions prior to conducting ship or airborne operations, and provide interpretive background for regional exploration already in progress.

Altimetric satellites provide data primarily of water-covered areas. The geoidal images avoid assumptions inherent in the preparation of Bouguer, free-air, and isostatic gravity maps. Oceanic data combined with continental gravimetric data are displayed as contour maps.

The synoptic view provided by high-order geoidal images makes it possible to trace crustal features such as fracture zones to the margin of continents. The images are of sufficient detail as to cast doubt on many correlations deduced on the basis of the oceanic magnetic anomalies. Crustal stretching and intraplate deformation may be more common than supposed.

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