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Disputation: Jan Daniel Morad

Doctoral candidate Daniel Morad at the Department of Geosciences, Faculty of Mathematics and Natural Sciences, is defending the thesis "Burial diagenesis and thermochemical sulfate reduction in the Arab gas reservoirs- clues to controls on H2S distribution" for the degree of Philosophiae Doctor.

Jan Daniel Morad. Foto: Private

Jan Daniel Morad. Foto: Private

Trial lecture - time and place

Friday 11 October, 10:15 - 11:00, Auditorium 1, the Geology building:

Hydrothermal dolomitization: settings, geochemistry and models

 

Conferral summary (In Norwegian)

I denne avhandlingen undersøkes biologiske, kjemiske og mekaniske prosesser som påvirker muligheten for å finne gass i kalksteiner av Jura alder. Studien viser at tilstedeværelsen av gass i reservoaret forhindrer eller forsinker flere kjemiske prosesser, som har ført til god reservoarkvalitet i de undersøkte kalksteinsintervallene.

Main research findings

Short summary about Morad’s dissertation:

This study shows that the timing of gas emplacement in carbonate reservoirs are significant for the reservoir quality evolution, because gas inhibit diagenesis and any further reservoir quality destruction. Therefore, the best reservoirs are in the crest (i.e. gas zone) of the anticline and not the flanks (i.e. water zone).

Stylolite between highly cemented and less cemented grainstone. The bedding-parallel orientation of most stylolites in the Arab Formation suggests that formation was due to overburden stress during burial. Dolomite cement is common along the stylolites and is indicating that the stylolites have been acting as conduits for hot basinal brines. This type of stylolitization in grainstones is assumed to have resulted in calcite cementation in adjacent inter- and intragranular pores. Foto (thin section): Daniel Jan Morad 
Stylolite between highly cemented and less cemented grainstone. The bedding-parallel orientation of most stylolites in the Arab Formation suggests that formation was due to overburden stress during burial. Dolomite cement is common along the stylolites and is indicating that the stylolites have been acting as conduits for hot basinal brines. This type of stylolitization in grainstones is assumed to have resulted in calcite cementation in adjacent inter- and intragranular pores. Photo (thin section): Daniel Morad 

This thesis combines several methods to unravel the chemical, biological and mechanical evolution (i.e. diagenesis) of Upper Jurassic carbonate rocks onshore Abu Dhabi in the United Arab Emirates. These methods have allowed us to get a better understanding of temperatures, chemical compositions of fluids, type of organisms and structures present, as well as the tectonic events that impacted the investigated carbonate rocks. This study shows that it is important to combine diagenesis with burial history and tectonic events in order to improve our knowledge of gas reservoirs in the Arabian Gulf and elsewhere.

Photo and other information:

Press photo: Daniel Morad (portrait)

Other photo material: Stylolite between highly cemented and less cemented grainstone | Thin section/1000px. Photo: Daniel Morad 

Published Sep. 30, 2019 10:41 AM - Last modified Sep. 30, 2019 11:49 AM