TS8.2 EDI

It has become increasingly apparent that many rifts contain a component of obliquity. As such, a spectrum of obliquity can be recognised from orthogonal rifts through to pure strike-slip tectonics. At one end of the spectrum, continental strike-slip and deep oceanic transform faults form plate boundaries and are intrinsic features of plate tectonics. At the other end of the spectrum, extension occurs perpendicular to the rift axis or spreading centre. Between these two-end member situations, a complete range of oblique to extensional processes can occur.
The cause of rift obliquity and transform tectonics has been attributed to a range of driving mechanisms, including: oblique crustal and mantle inheritance, a reduced force required for plastic yielding, changes in far-field forces, asthenospheric dynamics, and grain size changes in the lower crust and mantle. The effects of obliquity on rift and transform evolution are extensive, often leading to unique structural settings dominated by transtensional and transpressional processes. The spatio-temporal overlap of distinctive rifting events (governed by transtensional, transpressional or orthogonal kinematics) can result in strongly segmented 3D rift architectures that may influence subsequent rift events and compressional reactivation (i.e. inversion). Rift obliquity and transform faults have been related to a diverse array of phenomena including: rift and breakup-related magmatism, subduction initiation, supercontinent dispersal, microcontinent cleaving, structural inheritance, relative plate motion, hydrocarbon systems, geothermal energy potential, lithosphere-hydrosphere interaction, and hazardous seismic activity.
In this session, we will explore the formation and evolution, the physical properties, and the extinction and reactivation of orthogonal to oblique and transform extensional systems and large deep oceanic transform-fracture systems. We seek contributions that address these topics from all geoscience disciplines using both geological and geophysical data, numerical and analogue modelling, and/or direct rock studies from different settings and natural examples, at all scales. Special emphasis will be given to multidisciplinary studies.

Co-organized by GD5
Convener: Alexander L. PeaceECSECS | Co-conveners: Patricia Cadenas MartínezECSECS, Georgios-Pavlos FarangitakisECSECS, Jordan J. J. PhetheanECSECS, Louise Watremez

It has become increasingly apparent that many rifts contain a component of obliquity. As such, a spectrum of obliquity can be recognised from orthogonal rifts through to pure strike-slip tectonics. At one end of the spectrum, continental strike-slip and deep oceanic transform faults form plate boundaries and are intrinsic features of plate tectonics. At the other end of the spectrum, extension occurs perpendicular to the rift axis or spreading centre. Between these two-end member situations, a complete range of oblique to extensional processes can occur.
The cause of rift obliquity and transform tectonics has been attributed to a range of driving mechanisms, including: oblique crustal and mantle inheritance, a reduced force required for plastic yielding, changes in far-field forces, asthenospheric dynamics, and grain size changes in the lower crust and mantle. The effects of obliquity on rift and transform evolution are extensive, often leading to unique structural settings dominated by transtensional and transpressional processes. The spatio-temporal overlap of distinctive rifting events (governed by transtensional, transpressional or orthogonal kinematics) can result in strongly segmented 3D rift architectures that may influence subsequent rift events and compressional reactivation (i.e. inversion). Rift obliquity and transform faults have been related to a diverse array of phenomena including: rift and breakup-related magmatism, subduction initiation, supercontinent dispersal, microcontinent cleaving, structural inheritance, relative plate motion, hydrocarbon systems, geothermal energy potential, lithosphere-hydrosphere interaction, and hazardous seismic activity.
In this session, we will explore the formation and evolution, the physical properties, and the extinction and reactivation of orthogonal to oblique and transform extensional systems and large deep oceanic transform-fracture systems. We seek contributions that address these topics from all geoscience disciplines using both geological and geophysical data, numerical and analogue modelling, and/or direct rock studies from different settings and natural examples, at all scales. Special emphasis will be given to multidisciplinary studies.