Late Neoproterozoic volcano-sedimentary successions of Wadi Rufaiyil, southern Sinai, Egypt: A case of transition from late- to post-collisional magmatism

Azer, Mokhles K.; Farahat, Esam S.

doi:10.1016/j.jseaes.2011.06.016

Cited by 40 publications

(16 citation statements)

References 85 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Pre‐Neoproterozoic crust that complicates understanding of magma genesis in other parts of the EAO (e.g., Saharan Metacraton + Mozambique Belt [ Fritz et al ., ]) is limited in the juvenile ANS. Recent studies in the Sinai Peninsula [ Eyal et al ., ; Azer and Farahat , ; Khalil et al ., ; Moreno et al ., ] identify two distinct mantle sources involved in the transition from late‐orogenic calc‐alkaline magmatism to post‐orogenic alkaline magmatism associated with terminal collision, tectonic escape along the Najd Fault System [ Stern , ], and cratonisation. However, isotopic evidence indicates that this magmatism (regardless of age or element geochemistry) is juvenile ( ε Nd +2.5 to +5.5 [ Stoeser and Frost , ]), which highly favors mafic underplating as proposed by Stern and Johnson [].…”

Section: Introductionmentioning

confidence: 99%

A discussion on the tectonic implications of Ediacaran late- to post-orogenic A-type granite in the northeastern Arabian Shield, Saudi Arabia

et al. 2017

View full text Add to dashboard Cite

The transition from late‐orogenic to post‐orogenic magmatism following major orogenic episodes such as the Neoproterozoic to Cambrian East African Orogen (EAO) is an important, yet not well‐understood geological event marking the cessation of subduction‐controlled magmatism between buoyant lithospheric fragments. Forming the northern part of the EAO in the Arabian‐Nubian Shield are three granitic suites that successively intruded the same northeastern area and post‐date the ~640 Ma major orogenic episode: (1) 620–600 Ma alkali feldspar (hypersolvous) granite with alkaline/ferroan/A‐type geochemistry, (2) 599 Ma granite cumulates (some garnet‐bearing) with calc‐alkaline/magnesian affinities, and (3) 584–566 Ma alkali feldspar (hypersolvous) granite (aegirine‐bearing) with a distinctive peralkaline/ferroan/A‐type signature. Combining whole‐rock geochemistry from the southern and northern Arabian Shield, suites 1 and 2 are suggested to be products of late‐orogenic slab tear/rollback inducing asthenospheric mantle injection and lower crustal melting/fractionation toward A‐type/ferroan geochemistry. Suite 3, however, is suggested to be produced by post‐orogenic lithospheric delamination, which replaced the older mantle with new asthenospheric (rare earth element‐enriched) mantle that ultimately becomes the thermal boundary layer of the new lithosphere. Major shear zones, such as the 620–540 Ma Najd Fault System (NFS), are some of the last tectonic events recorded across the Arabian Shield. Data presented here suggest that the NFS is directly related to the late‐orogenic (620–600 Ma) slab tear/rollback in the northeastern Shield as it met with opposing subduction polarity in the southern Shield. Furthermore, this study infers that east and west Gondwana amalgamation interacted with opposing convergence reflected by the NFS.

show abstract

Section: Introductionmentioning

confidence: 99%

A discussion on the tectonic implications of Ediacaran late- to post-orogenic A-type granite in the northeastern Arabian Shield, Saudi Arabia

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Prior studies have argued that systematic changes in granite chemistry in part reflect changes in a mantle component of the granite magmas from depleted mid-ocean ridge basalt (MORB)-like to enriched (Stein and Goldstein 1996;Stoeser and Frost 2006;Be'eri-Shlevin et al 2010). Focusing on A-type granites (Frost et al 2011), which are commonly associated with fractional crystallization of magmas produced during crustal extension (Turner et al 1992), recent ANS studies in Sinai suggest that two distinct mantle sources are involved in the tran-sition from postcollisional/calcalkaline to anorogenic alkaline granitoids (Eyal et al 2010;Azer and Farahat 2011). This apparent source transition combined with a trend toward very voluminous, widespread magmatism following supercontinental amalgamation is often attributed to the impact of slab rollback/tear (Gvirtzman and Nur 1999;Flowerdew et al 2013) and/or to lithospheric delamination (Avigad and Gvirtzman 2009).…”

Section: Introductionmentioning

confidence: 99%

Zircon Geochemical and Geochronological Constraints on Contaminated and Enriched Mantle Sources beneath the Arabian Shield, Saudi Arabia

Robinson

Foden

Collins

2015

The Journal of Geology

View full text Add to dashboard Cite

A B S T R A C TArabian Shield granitic zircon geochemistry provides insight into the petrogenetic processes involved in generating one of the planet's largest tracts of juvenile Neoproterozoic crust. New zircon geochemistry supports previous U-Pb and whole-rock data that defined four magmatic groups: (1) ∼870-675 Ma island arc and synorogenic I-type granitoids (IA1Syn), (2) ∼640-585 Ma I-and A-type granitoids from the Nabitah and Halaban Suture (NHSG), (3) ∼610-600 Ma postorogenic perthitic (hypersolvus) A-type granitoids (POPG), and (4) !600 Ma anorogenic aegirine-bearing perthitic (hypersolvus) A-type granitoids (AAPG). The low Nb (∼1-300 ppm) and intrasuite rare earth element variation in IA1Syn and NHSG zircons indicates that these suites are derivatives of contaminated mantle followed by fractionation. AAPG suites, however, have higher Nb content (∼10-400 ppm) and are derived from limited crust-enriched mantle interaction. Each of the IA, Syn, and NHSG suites have discrete granite subsuites distinguished using zircon morphology and geochemistry whose U-Pb ages in each case form three groups. The IA subgroups are ∼867, ∼847, and ∼829 Ma; the Syn subgroups are ∼730, 716, and 696 Ma; and the NHSG subgroups are ∼636, ∼610, and ∼594 Ma. This apparent subevent repetition suggests some form of magmatic pulsing in the Arabian Shield. It is suggested that IA1Syn suites reflect typical volcanic arc granite settings and incremental subduction/accretion of eastward-migrating oceanic fragments of the East African Orogen. The appearance of ∼636 Ma A-type magmatism within suture zones (NHSG) is possibly derived from a long-lived (∼50 m.yr.) melting, assimilation, storage, and homogenization (MASH) zone resulting from an ∼640 Ma slab tear. These A-types are distinguished from more-enriched anorogenic (!600 Ma) A-types, possibly associated with lithospheric delamination.

show abstract

“…(d) MALI (modified alkali lime index) vs. SiO 2 (after Frost et al, 2001). Sinai DV include data for Ediacaran lavas from Rutig (Be'eri-Shlevin et al, 2011), Kid Volcanics (El-Bialy, 2010), and Wadi Rufaiyil(Azer and Farahat, 2011). In (a) and (b) the fields of ophiolitic metavolcanics (older metavolcanics, OMV), island arc metavolcanics (younger metavolcanics, YMV) and Dokhan Volcanics (DV) are fromAli K.A.…”

mentioning

confidence: 99%

“…Sinai DV (dashed field) include data for Ediacaran lavas from Rutig(Be'eri-Shlevin et al, 2011), Kid Volcanics (El-Bialy, 2010, and Wadi Rufaiyil(Azer and Farahat, 2011).…”

mentioning

confidence: 99%

Geochemistry, geochronology, and Sr–Nd isotopes of the Late Neoproterozoic Wadi Kid volcano-sedimentary rocks, Southern Sinai, Egypt: Implications for tectonic setting and crustal evolution

Moghazi

Ali

Wilde

et al. 2012

Lithos

View full text Add to dashboard Cite

Late Neoproterozoic volcano-sedimentary successions of Wadi Rufaiyil, southern Sinai, Egypt: A case of transition from late- to post-collisional magmatism

Cited by 40 publications

References 85 publications

A discussion on the tectonic implications of Ediacaran late- to post-orogenic A-type granite in the northeastern Arabian Shield, Saudi Arabia

A discussion on the tectonic implications of Ediacaran late- to post-orogenic A-type granite in the northeastern Arabian Shield, Saudi Arabia

Zircon Geochemical and Geochronological Constraints on Contaminated and Enriched Mantle Sources beneath the Arabian Shield, Saudi Arabia

Geochemistry, geochronology, and Sr–Nd isotopes of the Late Neoproterozoic Wadi Kid volcano-sedimentary rocks, Southern Sinai, Egypt: Implications for tectonic setting and crustal evolution

Contact Info

Product

Resources

About