Geodynamikk og Bassengstudier
Masterprosjekt GEO - William Helland-Hansen

Sedimentary processes for the filling of interdistributary bayfills, Neslen Formation, Book Cliffs

This master's project is available from the intake of August 2019


 Project description

The Campanian Neslen Formation crops out in the middle and eastern parts of the Book Cliffs, Utah and Colorado. The formation is composed of delta plain and interdistributary bay deposits. In the study area, the Neslen Formation can be subdivided into three, based on stratigraphic architecture. The Lower and Upper Neslen intervals are composed of fluvial deposits, with various fluvial styles, whereas the Middle Neslen Interval is composed of marginal marine interdistributary bayfill deposits. In the latter interval, six bayfill units are stacked, separated by short lived allocyclic flooding surfaces (Bayfill #1-6).
This Master Thesis will focus on the uppermost 6-8 meters of the Middle Neslen Interval, investigating the Bayfill#5 and Bayfill#6 units along a 5 km long transect that is subparallel to the depositional dip direction. The main task is to understand the processes for the sedimentary infilling of an interdistributary bay, and the nature of progradation into the lagoonal area. Detailed sedimentary logging should be carried out to understand lateral changes in lithofacies and facies associations, and to identify and map the distribution of allocyclic and autocyclic surfaces.
Equinor has been working in the Neslen Formation for many years, and it is suggested to be consistent with their classification of lithofacies and facies associations.

Proposed course plan during the master's degree (60 ECTS):

Will be decided between the student and the supervisor.

Field work:

Field work in the Book Cliffs, Utah in August/September 2019.

Neslen Formation Book Cliffs
William Helland-Hansen