Department of Earth Science
Masterprosjekt: Energi - Ressurser - geofarer

Interaction of igneous sills and host rocks of Curtis Formation, Eastern Utah

This master's project was designed for Kristin Aven who started as a master's student in the GBS-group, autumn 2021, at the Department of Earth Sciences. Below is her planned project description.

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Project description
Mafic sill intrusions commonly occur as layer-parallel conduits of magma within sedimentary basins. Recent work has shown that the emplacement of such sills is strongly controlled by host-rock lithology, in particular by weak mudstone layers. The emplacement of sill intrusions in cemented sandstone deposits, with only sparse mudstone beds, has not been studied in detail before. Such understanding is important to plan resource extraction in volcanic basins and to interpret earthquake activity during volcanic unrest. 
The Mussentuchit Wash in Eastern Utah exposes a c. 15 m thick sill emplaced in the shallow-marine Curtis Sandstone, where only thin mudstone, limestone and gypsum beds are present within the otherwise sandy deposits. This locality provides a world-class outcrop for investigating the relationship between host rock and mafic intrusions. The main goal is to investigate how host-rock heterogeneity has controlled emplacement features of the sills (broken bridges, steps, brecciation features, and nature of contact between sill and host-rock). A secondary goal is to map and understand the bleaching of the host-rock near the sill using mineralogical and geochemical methods. These goals will be achieved by detailed investigations of the outcrop in virtual outcrop models, detailed sedimentological analysis, and thin section analysis of the outcrop.

Proposed course plan during the master's degree (60 ECTS):
GEOV210 – Platetektonikk (10p)
GEOV242 - Magmatisk og metamorf petrologi (10p)
GEOV 261 – Bassenganalyse og tolkning av undergrunnsdata (10p)
GEOV272 - Seismisk tolkning (10p)
GEOV345 - Regionalgeologisk feltkurs til Vestlandet (5p)
GEOV352 - Utah Feltkurs (5p)
GEOV360 - Videregående klastisk sedimentologi (10p)
GEOV364 – Videregående bassenganalyse (5p)

Felt- lab- og analysearbeid
Virtual outcrop models
Sedimentological field work
Thin section and other mineralogical and geochemical techniques