Abstract We present a summary of peridotite in the Subantarctic (46–60° S) surrounding Antarctic Plate. Peridotite xenoliths occur on Kerguelen Islands and Auckland Islands. The are underlain by plume, whereas part continental Zealandia, which is Gondwana-rifted fragment. Small amounts serpentinized has been dredged from fracture zones Southeast Indian Ridge, Southwest Ridge Pacific represent u...

[1] Surface topography and associated gravity anomalies above a layer resembling continental lithosphere, whose mantle part is gravitationally unstable, depend strongly on the ratio of viscosities of the lower-density crustal part to that of the mantle part. For linear stability analysis, growth rates of Rayleigh-Taylor instabilities depend largely on the wave number, or wavelength, of the pert...

[1] The India-Eurasia collision and the decratonization of the North China Craton have drawn much attention from the scientific community. Here we provide the first large-scale S wave velocity model for China (CH11-S) based on constraints from both teleseismic surface and body waves. We take advantage of the recent deployment of the 140 permanent stations of the Chinese Digital Seismic Network ...

Intense devolatilization and chemical-density differentiation attended accretion of planetesimals on the primordial Earth. These processes gradually abated after cooling and solidification of an early magma ocean. By 4.3 or 4.2 Ga, water oceans were present, so surface temperatures had fallen far below lowpressure solidi of dry peridotite, basalt, and granite, ~1300, ~1120, and ~950 °C, respect...

New measurements of Os, He, Sr and Nd isotopes, along with major and trace elements, are presented for basalts from the three volcanic flank zones in Iceland and from Jan Mayen Island. The Os/Os ratios in lavas with <30 ppt Os (n = 4) are elevated compared to ratios in coexisting olivine and appear to be contaminated at a shallow level. The Os/Os ratios in the remaining lavas with >30 ppt Os (n...

Global compilations of surface heat flow data from stable, Precambrian terrains show a statistically significant secular change from 41"11 mWrm in Archean to 55"17 mWrm in Proterozoic regions far removed from Archean cratons. Using the tectonothermal age of the continents coupled with average heat flow for different age provinces yields a mean 2 Ž continental surface heat flow between 47 and 49...

Subducting lithospheric plates are the cool, downwelling limbs of mantle convection and the negative buoyancy of subducting slabs (slab pull) drives plate tectonics [Forsyth and Uyeda, 1975]. Subduction zones are regions of intense earthquake activity, explosive volcanism, and complex mass transfer between the crust, mantle, hydrosphere, and atmosphere. In this contribution, I present subductio...

[1] The initial oceanic crust along volcanic passive margins is a factor of 3 greater than that of typical oceanic crust (20 versus 6–7 km). Convection driven by the edge of the continental lithosphere may cause mantle material to circulate through the shallow zone of significant melting beneath the nascent ocean basin and cause the volume of melted mantle to exceed that required to replace the...

[1] Laboratory and numerical experiments show that when a chemically different layer overlies a hotter but otherwise denser layer, analogous to continental mantle lithosphere over asthenosphere, convective stability depends strongly on both the critical Rayleigh number and the buoyancy number, B, of the lithosphere-like layer. Sufficient cooling at low buoyancy number results in an oscillatory ...

The locations of volcanic islands may be controlled by thin or extending parts of the lithosphere over a partially molten asthenosphere [Anderson and Bass, 1984; Favela and Anderson, 2000], by edge effects near the boundaries of thick cratonic lithosphere [Anderson, 1998], or by narrow jets of hot mantle rising from deep within the mantle [Campbell and Griffiths, 1992; Morgan, 1971; Wilson, 198...