Peter van Keken a, David A. Yuen b and Arie van den Berg a Received November 21, 1991, revision accepted June 17, 1992 Recent laboratory work has suggested that the rheology of the lower mantle may be Newtonian. We have studied the time-dependent dynamics of plumes interacting with a rheological interface separating an upper non-Newtonian mantle and a Newtonian lower mantle . Pulsating diapiric...

Introduction. The internal structure of a planet provides essential clues about its origin and evolution. At present we can only claim insight into the internal structure of the Earth and Moon. Seismology has provided by far the most specific information on the interior of these two bodies. However, because no seismic data are available for Mars, it is neccessary to look elsewhere for constrain...

The Earth’s long-wavelength geoid anomalies have long been used to constrain the dynamics and viscosity structure of the mantle in an isochemical, whole mantle convection model. However, there is strong evidence that the seismically observed large low shear velocity provinces (LLSVPs) in the lower mantle underneath the Pacific and Africa are chemically distinct and likely denser than the ambien...

[1] Accurately inferring the radially anisotropic structure of the mantle using seismic waveforms requires correcting for the effects of crustal structure on waveforms. Recent studies have quantified the importance of accurate crustal corrections when mapping upper mantle structure using surface waves and overtones. Here, we explore the effects of crustal corrections on the retrieval of deep ma...

The intent of this analysis is to explore the influence of thermal radiation paired with variable thermal conductivity on MHD micropolar fluid flow over an upper surface. The novelty of the present model is to consider the fluid flow along an upper horizontal surface of a paraboloid of revolution (uhspr) with the porous medium.  This physical phenomenon is described by a set of coupled...

Using a complex of remote and surface geophysical methods in the eastern part East European Platform, regional meridional heterogeneitieswere revealed; it isshown that these heterogeneitiescan becaused by low-density magnetically active rocks thecrystalline crust mantle. The totality geological data indicates relationship heterogeneities with transcontinental deep faults.

[1] We analyze moment tensor solutions from deep subduction zone earthquakes to determine global slab deformation patterns. Inferred strain rates are compared to predicted deformation patterns from fluid models to help constrain the first‐order radial and lateral viscosity structure of the Earth. While all slabs that reach the lower mantle are compressed at their tip, intermediate depth pattern...

The eastern European Alps are shaped by the indentation of Adria into Europe. Recent tomography, depicting detached slab fragments, has been interpreted as evidence continuous southward subduction lithosphere, contrary to an often-invoked polarity reversal. Orogen-scale exhumation, driven rock displacement along active faults, may reflect within framework doubly-vergent Coulomb wedge theory, pr...