9217707 Lonsdale This project includes a field program to geophysical survey and geologically sample the two largest transform fault zones on the Pacific-Antarctic plate boundary. The principal objectives are: (1) to understand the structures and tectonics of long, fast- slipping transform faults; (2) to test structural inferences based largely on remotely sensed seismicity and satellite altimetry; (3) to learn the geologic composition of the crustal rocks exposed in the transforms, and (4) to exploit known outcrops of lower crustal and upper mantle rocks that the usually inaccessible to dredging on fast-spreading ridges. ***
