Ontology highlight
ABSTRACT:
SUBMITTER: Helmberger D
PROVIDER: S-EPMC1297654 | biostudies-literature | 2005 Nov
REPOSITORIES: biostudies-literature
Helmberger D D Lay T T Ni S S Gurnis M M
Proceedings of the National Academy of Sciences of the United States of America 20051010 48
Seismologists have known for many years that the lowermost mantle of the Earth is complex. Models based on observed seismic phases sampling this region include relatively sharp horizontal discontinuities with strong zones of anisotropy, nearly vertical contrasts in structure, and small pockets of ultralow velocity zones (ULVZs). This diversity of structures is beginning to be understood in terms of geodynamics and mineral physics, with dense partial melts causing the ULVZs and a postperovskite s ...[more]