@article{fdi:010075564,
  title = {{E}pisodic collisional orogenesis and lower crust exhumation during the {P}alaeoproterozoic {E}burnean {O}rogeny : evidence from the {S}efwi {G}reenstone {B}elt, {W}est {A}frican {C}raton},
  author = {{M}c{F}arlane, {H}. {B}. and {A}illeres, {L}. and {B}etts, {P}. and {G}anne, {J}{\'e}r{\^o}me and {B}aratoux, {L}enka and {J}essell, {M}. {W}. and {B}lock, {S}.},
  editor = {},
  language = {{ENG}},
  abstract = {{N}ew constraints on the architecture, deformation sequence and tectonic evolution of the sparsely exposed {P}alaeoproterozoic {S}efwi {G}reenstone {B}elt (ca. 2200-2070 {M}a) in {SW} {G}hana are derived from the integration of field observations, structural mapping and interpretation of regional airborne geophysical data. {O}ur findings provide new insights into the tectonic evolution of the {W}est {A}frican {C}raton during the {P}alaeoproterozoic {E}burnean {O}rogeny (ca. 2150-2070 {M}a). {D}omains of contrasting metamorphic grade comprising high-grade paragneisses and meta-volcanic rocks are tectonically juxtaposed against low-grade volcano-sedimentary packages. {T}he earliest deformation event is characterised by a bedding-parallel high-grade metamorphic foliation ({S}-1) that is axial planar to isoclinal folds formed during {NNW}-{SSE} shortening and late-{D}-1 partial melting. {T}his crustal thickening event generated biotite +/- muscovite granites emplaced parallel to the {NW} margin of the {S}efwi {B}elt between ca. 2092 and 2081 {M}a, providing a minimum age for {D}-1. {D}-2 deformation is characterised by a moderate to steeply dipping, {ENE}-{WSW} to {NE}-{SW} striking, penetrative {S}-2 mineral foliation. {W}ithin the {S}efwi {B}elt, coaxial {F}-2 fold axes and {L}-2 stretching lineations pitch shallowly {ENE}-{WSW} to {NE}-{SW}, oblique to the major shear zones, indicative of {ENE}-{WSW} transtension and associated constrictional deformation. {D}ifferential exhumation of middle and lower crustal segments along {NNE}-striking {D}-2 extensional detachments was coincident with sinistral oblique reactivation of {NE}-{SW} regional-scale shear zones. {T}he timing of exhumation is constrained by metamorphic monazite {U}-{P}b ages at ca. 2073 {M}a. {S}ubsequent {E}-{W} shortening is associated with dextral reactivation of regional {NE}-{SW} striking shear zones and refolding of earlier structures away from the major shear zones. {W}e propose that the {NW} margin of the {S}efwi {B}elt represents the collision ({D}-1) of southern {G}hana and central and {NW} {G}hana/{I}vory {C}oast which record different tectonic histories. {F}urthermore, we suggest the amalgamation of the {W}est {A}frican {C}raton is the product of episodic collisional orogenesis, providing new insights into the evolution of orogenic processes during the {P}alaeoproterozoic.},
  keywords = {{P}alaeoproterozoic ; {C}ollisional orogenesis ; {T}ranstension ; {E}xhumation ; {W}est {A}frican {C}raton ; {S}efwi {G}reenstone {B}elt ; {AFRIQUE} {DE} {L}'{OUEST} ; {GHANA}},
  booktitle = {},
  journal = {{P}recambrian {R}esearch},
  volume = {325},
  numero = {},
  pages = {88--110},
  ISSN = {0301-9268},
  year = {2019},
  DOI = {10.1016/j.precamres.2019.02.012},
  URL = {https://www.documentation.ird.fr/hor/fdi:010075564},
}