Comparison of geophysical sections of the Earth crust with the results of deep drilling in the Fennoscandian Shield
© Sharov N.V.
The nature of geoacoustic waves is discussed, based on comparison of the results of seismic and acoustic studies in the
Fennoscandian Shield with the drilling record of the Kola Superdeep Borehole: 12262 m (1970-1990), Russia; Gravberg 6337 m
(1986-1987), Sweden; Outokumpu - 2516 m (2004-2005), Finland; Pogranichnaya - 5200 m (2004-2006), Russia; Onezhskaya - 3537 m
(2007-2009), Russia. The assumption that the crystalline crust has a heterogeneous structure with gradient variations and elastic wave velocity inversions
and the vertically and laterally varying degree of differentiation is well-based. The nature of seismic boundaries depends on differences in rock
composition and the physical state of the rocks. The results of geophysical studies, conducted during deep drilling in the Fennoscandian
Shield, make investigators re-interpret the geological and geophysical data.