Nowhere on the present-day Earth can the transition from a continental to an oceanic rift be observed and studied better than in the Red Sea region, where three rifts in different stages of evolution meet in a triple point located in the Afar region. A thermal and/or compositional mantle plume may have risen from the upper mantle below Afar already at *30 Ma, and may have triggered, at least in...

Ocean Drilling Program Leg 210 was devoted to studying the history of rifting and postrift sedimentation in the Newfoundland–Iberia rift. Drilling was conducted in the Newfoundland Basin along a transect conjugate to previous drilling on the Iberia margin (Legs 149 and 173). This was the first time that deep-sea drilling has been conducted on both sides of a nonvolcanic rift in order to underst...

Abstract. For more than half a century, exploring complete sequence of the oceanic crust from seafloor through Mohorovičić discontinuity (Moho) and into uppermost mantle has been one most challenging missions scientific ocean drilling. Such technological achievement would provide humankind with profound insights largest realm our planet expand fundamental understanding Earth's deep interior its...

Zircon age peaks at 2100–1650 and 1200–1000 Ma correlate with craton collisions in the growth of supercontinents Nuna and Rodinia, respectively, with a time interval between collisions mostly <50 Myr (range 0–250 Myr). Collisional orogens are two types: those with subduction durations <500 Myr and those ≥500 Myr. The latter group comprises orogens with long-lived accretionary stages between Nun...

the oligocene-miocene granitic rocks of deh siahan, part of central iranian volcanic belt, are intruded into eocene volcano-sedimentary complex where their contact is marked by albite-epidote hornblende hornfels facies and granitic apophyses. the granitic rocks show enhanced lil element abundances and low hfs/lil ratios. geochemical data, various trace element discriminant diagrams, enhanced y/...

S U M M A R Y Pacific Ocean crust west of southwest North America was formed by Cenozoic seafloor spreading between the large Pacific Plate and smaller microplates. The eastern limit of this seafloor, the continent–ocean boundary, is the fossil trench along which the microplates subducted and were mostly destroyed in Miocene time. The Pacific–North America Plate boundary motion today is concent...

Subduction zones are the primary regions on Earth today where crust recycling takes place, and through geological time they have been the sites of continent formation. Many of the key elements (e.g., Th, rare earth elements, Ba, and Be) that are important in understanding crustal growth are sequestered in the sedimentary column and in the uppermost oxidized portions of the volcanic section of o...

Sonobuoys provide an alternative to using long streamers while conducting multi-channel seismic (MCS) studies, in order to provide deeper velocity control. We present analysis and modeling techniques for interpreting the sonobuoy data and illustrate the method with ten overlapping sonobuoys collected in the Ross Sea, offshore from Antarctica. We demonstrate the importance of using the MCS data ...