Docenturföreläsning

Institutionen för geovetenskaper inbjuder härmed alla intresserade till docenturföreläsning i ämnet geofysik med inriktning mot seismologi: "Receiver Functions – From raw data to geodynamic interpretation".

Föreläsare: Christian Schiffer, PhD

Titel: Receiver Functions – From raw data to geodynamic interpretation

Datum: 16 maj 2024, 13.15

Plats: Gm116, Norrland II, Geocentrum, Villavägen 16, 75236 Uppsala och Zoom: https://uu-se.zoom.us/j/66633390793

Ordförande: professor Alireza Malehmir.

Docenturnämndens representant: professor Jan Isberg

Sammanfattning:

Imaging of the Earth’s structure is a major application in earthquake seismology. Various methods are able to extract information from, image or model different aspects of Earth’s seismic structure, including analysis of travel time curves, tomographic methods, forward modelling, wave splitting (birefringence) analysis and analysis of the seismic waveform itself. One method developed in the 1970s and 1980s, has in the past 30 years become a standard method for imaging the Earth structure to depths of down to ~1000 km – the so-called receiver function method.

Receiver functions exploit incoming teleseismic waves that interact with sub-horizontal velocity discontinuities beneath a seismometer. The incident seismic wave reflects, refracts and converts at such boundaries (i.e. Snell’s Law). For example, a compressional wave reflects and refracts at a discontinuity, but at the same time converts to a slower shear wave. Because of the difference compressional and shear wave velocities, the converted shear wave arrives later. Receiver function processing, most fundamentally involving deconvolution, removes complexity arising from the earthquake source, the path and the instrument, in order to isolate signals representing the velocity structure underlying the recording station.

The purpose of this lecture is to present the receiver function method starting with the fundamentals, followed by data processing procedures, commonly used receiver function analyses and finally, applications and interpretations based on some case studies. The lecture will conclude by summarising the potentials and limitations of the method.

Föreläsningen, som är ett lärarprov för den som ansökt om att bli antagen som docent, ska kunna följas av studenter och andra med kunskaper på grundutbildningsnivå inom ämnet, men kan även vara av intresse för en bredare publik. Föreläsningen varar 40-45 minuter med efterföljande diskussion och kommer att ges på engelska.

Välkomna!