Romanche fracture zone: Structure, evolution, and geodynamics

This work is based on survey data from the 13th and 16th cruises of the R/V Akademik Nikolai Strakhov. The tectonic structure of the Romanche fracture zone in the Equatorial Atlantic is considered. Based on its dynamics, kinematics and historical evolution, the zone does not seem to be a uniform structure. Its segments are of different age and evolved according to different dynamic and kinematic laws. The fracture zone is not continuous in space: deformations complicating it migrate both along and a cross its strike, creating new fracture zones with somewhat different orientation. Three geodynamic systems are recognized within the fracture zone, namely Rom 1, Rom 2 and Rom 3.   In the eastern junction of the rift and the Romanche fracture zone, the rift valley jumps northward with simultaneous prograding. A "dry" spreading mode is pronounced in the region.