title: Strain accommodation by slow slip and dyking in a youthful continental rift, East Africa.
abstract: Continental rifts begin and develop through repeated episodes of faulting and magmatism, but strain partitioning between faulting and magmatism during discrete rifting episodes remains poorly documented. In highly evolved rifts, tensile stresses from far-field plate motions accumulate over decades before being released during relatively short time intervals by faulting and magmatic intrusions. These rifting crises are rarely observed in thick lithosphere during the initial stages of rifting. Here we show that most of the strain during the July-August 2007 seismic crisis in the weakly extended Natron rift, Tanzania, was released aseismically. Deformation was achieved by slow slip on a normal fault that promoted subsequent dyke intrusion by stress unclamping. This event provides compelling evidence for strain accommodation by magma intrusion, in addition to slip along normal faults, during the initial stages of continental rifting and before significant crustal thinning.
authors.affiliation: Purdue University, Department of Earth and Atmospheric Sciences, West Lafayette, Indiana 47906, USA. ecalais@purdue.edu
authors.forename: Eric
authors.initials: E
authors.lastname: Calais
authors.forename: Nicolas
authors.initials: N
authors.lastname: d'Oreye
authors.forename: Julie
authors.initials: J
authors.lastname: Albaric
authors.forename: Anne
authors.initials: A
authors.lastname: Deschamps
authors.forename: Damien
authors.initials: D
authors.lastname: Delvaux
authors.forename: Jacques
authors.initials: J
authors.lastname: Déverchère
authors.forename: Cynthia
authors.initials: C
authors.lastname: Ebinger
authors.forename: Richard W
authors.initials: RW
authors.lastname: Ferdinand
authors.forename: François
authors.initials: F
authors.lastname: Kervyn
authors.forename: Athanas S
authors.initials: AS
authors.lastname: Macheyeki
authors.forename: Anneleen
authors.initials: A
authors.lastname: Oyen
authors.forename: Julie
authors.initials: J
authors.lastname: Perrot
authors.forename: Elifuraha
authors.initials: E
authors.lastname: Saria
authors.forename: Benoît
authors.initials: B
authors.lastname: Smets
authors.forename: D Sarah
authors.initials: DS
authors.lastname: Stamps
authors.forename: Christelle
authors.initials: C
authors.lastname: Wauthier