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Iridium concentration and noble gas composition of Cretaceous-Tertiary boundary clay from Stevns Klint, Denmark
K-T boundary, iridium, noble gas
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2017/8/10
The Cretaceous-Tertiary (K-T) boundary about 65 million years ago records a mass extinction event caused by a bolide impact. K-T boundary clay collected from Stevns Klint, Denmark was investigated in ...
Nickel and helium evidence for melt above the core–mantle boundary
core–mantle boundary Nickel helium evidence
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2014/4/8
High
3
He/
4
He ratios in some basalts have generally been interpreted as originating in an incompletely degassed lower-mantle
source
1–9
. This helium source may have been isolated at the core...
SPLITTING EXTRAPOLATIONS FOR SOLVING BOUNDARY INTEGRAL EQUATIONSOF LINEAR ELASTICITY DIRICHLET PROBLEMS ON POLYGONS BY MECHANICAL QUADRATURE METHODS
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2007/12/12
Taking $h_m$ as the mesh width of a curved edge $\Gamma _m$ $(m=1,...,d$ )
of polygons and using quadrature rules for weakly singular integrals, this
paper presents mechanical quadrature methods for...