Anizotropija brzina seizmičkih S valova u području središnjih Dinarida određena analizom dvoloma SKS faze

master's thesis

• Title (english): S-waves anisotropy in the central Dinarides inferred using splitting of the SKS phase
• Author: Dominik Šipek
• Mentor: Josip Stipčević (mentor)
• Committee member: Josip Stipčević (predsjednik povjerenstva)
• Committee member: Marijan Herak (član povjerenstva)
• Committee member: Zvjezdana Bencetić-Klaić (član povjerenstva)
• Committee member: Tena Belinić Topić (član povjerenstva)
• Committee member: Ivana Herceg Bulić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Geophysics); Zagreb
• Defense date and country: 2023-10-05, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Geophysics; Seismology and Physics of the Earth's Interior

Abstract

Dinaridi su smješteni na granici Jadranske mikroploče i Euroazijske ploče, na području u kojem je subdukcija bila aktivna prije 45 mil. godina. Dvolom SKS faza je pojava čijim se proučavanjem mogu saznati informacije o anizotropiji gornjeg plašta promatranog područja. Obrađeno je 865 zapisa za ukupno 249 teleseizmičkih potresa sa seizmoloških stanica u širem Dinarskom području. Analize dvoloma ukazuju na orijentacije brzih osi u WSW-ENE smjeru koji je okomit na smjer pružanja Dinarida s razlikama u vremenima nailazaka kvazi S faza između 0.6 s do 1.6 s. Ovakva orijentacija brzih osi je u skladu s predloženim astenosferskim tokom kroz subdukcijski prozor ispod Dinarida. Za dobivene rezultate pruženo je teoretsko objašnjenje da je zabilježena anizotropija posljedica preferencijalne orijentacije minerala olivina u plaštu uzrokovana astenosferskim tokom.

Abstract (english)

Dinarides mountain chain is located at the border between Adria microplate and Eurasian plate, where subduction processes lasted until 45 mil. years ago. By observing SKS splitting events it is possible to infer the anisotropy in the uppermost mantle beneath the area of interest. SKS analysis was performed on 249 teleseismic events recorded on 865 seismograms at seismic stations in the wider Dinarides area. Evidence of seismic anisotropy was found with fast axis orientation in the WSW-ENE direction as well as delay times in the range from 0.6 s to 1.6 s. Fast axis direction is approximately perpendicular to the strike of the Dinarides, which implies that the registered anisotropy is caused by lattice preffered orientation of olivine crystals due to asthenospheric flow through the slab-gap beneath the Dinarides.

• Keywords: SKS dvolom; anizotropija; astenosfera; Jadranska mikroploča
• Keywords (english): SKS splitting; anisotropy; uperrmost mantle anisotropy; Adria
• Language: croatian
• URN:NBN: urn:nbn:hr:217:980729
• Study programme: Title: GRADUATE ACADEMIC RESEARCH PROGRAMME: MASTER OF PHYSICS AND GEOPHYSICS; MODULES: SEISMOLOGY AND SOLID EARTH PHYSICS, METEOROLOGY AND PHYSICAL OCEANOGRAPHY; specializations in: SEISMOLOGY AND SOLID EARTH PHYSICS, METEOROLOGY AND PHYSICAL OCEANOGRAPHY; Course: SEISMOLOGY AND SOLID EARTH PHYSICS; Study programme type: university; Study level: graduate; Academic / professional title: sveučilišni magistar fizike – geofizike (sveučilišni magistar fizike – geofizike)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-10-06 14:14:52