Science · 2009 · 99 citations · 23 references
Natural SciencesEarth SciencesGeologyCrustal GeophysicsGeochemistryMarine GeologyCrustal StructureMantle GeochemistryMineral GenesisPlutonic RocksSeafloor SpreadingCrustal AccretionCrustal Growth By AccretionCrystallizationMid-ocean RidgesOceanic Crust FormationSlow-spreading RidgesUranium-lead DatingUranium-lead Geochronology
Most of Earth's present-day crust formed at mid-ocean ridges. High-precision uranium-lead dating of zircons in gabbros from the Vema Fracture Zone on the Mid-Atlantic Ridge reveals that the crust there grew in a highly regular pattern characterized by shallow melt delivery. Combined with results from previous dating studies, this finding suggests that two distinct modes of crustal accretion occur along slow-spreading ridges. Individual samples record a zircon date range of 90,000 to 235,000 years, which is interpreted to reflect the time scale of zircon crystallization in oceanic plutonic rocks.
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Age, spreading rates, and spreading asymmetry of the world's ocean crust
R. Dietmar Müller, M. Sdrolias, Carmen Gaina et al. · Geochemistry Geophysics Geosystems · 2008 · 2.1K citations · Full text