Making and breaking an island arc: A new perspective from the Oligocene Kyushu-Palau arc, Philippine Sea

Arc Consistency in MAC: A New Perspective?

AC refers to algorithms that enforce arc consistency on a constraint network while MAC refers to a backtracking search scheme where after each instantiation of a variable, arc consistency is maintained (or enforced) on the new network. In this paper, we use mac to denote maintaining arc consistency in MAC. In all existing studies, mac is simply taken as an associate of an AC algorithm. In this ...

The West Philippine Basin: An Eocene to early Oligocene back arc basin opened between two opposed subduction zones

Melt inclusions from Marianas arc lavas: implications for the composition and formation of island arc magmas

We have measured the major and trace element compositions of a suite of olivine-hosted melt inclusions in basaltic lavas from the islands of Agrigan and Guguan (one sample each) from the Mariana arc, part of the larger Izu–Bonin–Mariana system. The two lava samples examined show distinctly different chemical signatures that are considered to represent the dominance of sediment melt (Agrigan) or...

14. Oligocene to Recent Calcareous Nannoplankton from the Philippine Sea, Deep Sea Drilling Project Leg 59

During Leg 59 of the Deep Sea Drilling Project, five sites (447 to 451) were occupied and seven holes drilled between Okinawa and Guam in the Philippine Sea (Fig. 1). All holes except Hole 447 yielded common calcareous nannoplankton at certain intervals cored. Nannoplankton assemblages and their age assignments will be discussed for each site, and fossil lists for selected samples from Holes 44...

Trace elements in anorthite megacrysts from the Kurile Island Arc: a window to across-arc geochemical variations in magma compositions

Anorthite megacrysts from twelve volcanic centers of the Kurile Island Arc were analyzed by the ion microprobe for concentrations of: Li, Be, B, F, Mg, P, Cl, K, Ti, Fe, Co, Rb, Sr, Y, Zr, Nb, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, and Pb. These 1–2-cm megacrysts are mainly found as early phenocrysts in basalts, but are also present in andesites, rhyolites and hybrid rocks from almost every studied vo...