The Earth's Inner Core

  title={The Earth's Inner Core},
  author={John A. Jacobs},
ALL seismic work indicates that at least part of the core of the earth is liquid, since no transverse waves have ever been observed to pass through it. It has been suggested, however, that the core contains an inner core beginning at a depth of approximately 5,000 km. which is solid, although no definite proof of this has ever been given. Bullen1, however, has shown that the rise in velocity of longitudinal waves at this depth can be explained by assuming it to be solid and of the same… 

The Earth's deep interior

The deep interior of the Earth is inaccessible to man and in some ways we know less about it t h an we do about the distant stars. However seismology has revealed certain details of the earth's

Structure of the Earth's inner core

Jacobs1 proposed that the Earth's inner core is growing through the freezing of outer-core material as the Earth gradually cools2. Recent studies have shown that compositional effects associated with

Fine-scale heterogeneity in the Earth's inner core

Observations of seismic waves scattered in the inner core which follow the expected arrival time of the body-wave reflection from the inner-core boundary are presented.

Seismological evidence for mosaic structure of the surface of the Earth's inner core

Here the authors analyse properties of waves precritically reflected from the Earth's inner core (PKiKP phases) that show significant variability in amplitude, consistent high-frequency content and stable travel times with respect to a standard Earth model and infer that the data are best explained by a mosaic structure of the inner core's surface.

Models of the Earth's Core

Combined inferences from seismology, high-pressure experiment and theory, geomagnetism, fluid dynamics, and current views of terrestrial planetary evolution lead to models of the earth's core with

Temperature Distribution within the Earth's Core

RECENTLY, Simon1 has presented a method of estimating the melting-point temperature of iron at high pressure. This is of considerable geophysical interest as it is frequently argued that the earth's

Structure and dynamics of Earth's inner core

Experimental constraints on light elements in the Earth’s outer core

The sound velocity measurements of a model core composition in the Fe-Ni-Si system at the outer core conditions by shock-wave experiments are reported, finding that this composition satisfies the requirements imposed by seismology, geochemistry, and some models of the early core formation.



Significance of radioactivity in geophysics ‐ Thermal history of the Earth

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Elasticity and Constitution of the Earth's Interior

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A method of estimating the melting‐point gradient in the Earth's mantle

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