Yellowstone: A 3D Regional Delaytime Inversion Using Multiple Constraints

The origin of the Yellowstone hotspot is a matter of debate where plume- and nonplume models are discussed. The aim of this work is to derive a high resolution 3-D regional P-wave velocity model which is compatible with constraints from a variety of different fields (e.g. geology, gravity, seismology). This provides a more comprehensive notion of the Yellowstone hotspot structure and may serve as basis and reference model for the later geodynamical modelling of the Yellowstone hotspot. The main focus is on the tomographic inversion of teleseismic delaytime data. Since the resulting model has to be consistent with many different constraints, these are incorporated as a priori information into the inversion. This is of advantage especially in the crustal regions of the model, where the resolution of the teleseismic delaytime inversion typically is rather poor. The inversion is done iteratively using 3D raytracing. The a priori information mainly consist of the geological surface structure, crustal models from local tomography and the topography of seismic discontinuities derived from receiver function analysis. In addition to that, the Bouguer gravity signal is used as additional dataset to constrain the crustal structure via the joint inversion of gravity and teleseismic data.