The investigators will compile a comprehensive geological map of the East Pacific Rise from 9 25 to 9 55 N using high-resolution DSL-120A sidescan data, ABE and Alvin scanning altimetric data, and Alvin and WHOI TowCam observations, digital photographs and geochemistry of recovered samples. A detailed analysis and mapping of all the volcanic flow contacts, fissures and faults imaged will be analyzed. Constraints will be placed on erupted volumes, flow lengths, fault throws, and fissure spacing. The project seeks to advance knowledge of submarine ridges, and the resulting data will be shared with the community and public via outreach activities, using both a website and an available database. Students will also be involved with the research.