PHYSICAL CHARACTERISTICS OF SEAMOUNTS AT THE CENTRAL SECTOR OF THE RIVERA PLATE, BASED ON MULTIBEAM BATHYMETRY AND MAGNETIC MARINE DATA

Since 2006, the oceanographic vessel B/O El PUMA from UNAM has surveyed the central sector of the Rivera plate to map the physical characteristics of three seamount chains seamounts and seven isolated volcanic edifices. This data set has provided greater detail on these underwater structures and their relationship to the seafloor morphology of this oceanic plate. Multibeam bathymetry and magnetic data were recorded simultaneously during seven oceanographic surveys (BABRIP06, MAMRIV07, MAMRIV08, MORTIC08, GUAYRIV10, BATIBAJA11 and MAMRIV12).

The goal of this study is to analyze the multibeam bathymetry and magnetic data on these seamounts, between the Rivera Rise (RR) and the Marias Island massif. The charts of the seamount relief provide evidences of several slope collapsing episodes at fourteen seamounts. The magnetic anomalies associated to these seamounts indicate that most of them were formed simultaneously during the formation of new oceanic crust. Only five seamounts have a magnetic polarity inversed to the surrounding magnetic seafloor fabric, indicating that the seamount was formed at later time. Further this data set will be integrated to the global seamount catalog, which it would be the first time that their physical characteristic would be documented, holding the following parameters: coordinates, shape, height, and associate to a chain.