Reservoir characterization of the Stø formation in the Hammerfest Basin, SW Barents Sea
A reservoir characterization of the Stø formation has been performed in two wells linked to the Snøhvit field within the Hammerfest Basin in the South-Western Barents Sea. The reservoir quality of the Stø formation has been described as a function of provenance, depositional environment and diagenes...
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ftoslouniv:oai:www.duo.uio.no:10852/52339 2023-05-15T15:38:55+02:00 Reservoir characterization of the Stø formation in the Hammerfest Basin, SW Barents Sea Hansen, Henrik Nygaard 2016 http://hdl.handle.net/10852/52339 http://urn.nb.no/URN:NBN:no-55554 eng eng http://urn.nb.no/URN:NBN:no-55554 Hansen, Henrik Nygaard. Reservoir characterization of the Stø formation in the Hammerfest Basin, SW Barents Sea. Master thesis, University of Oslo, 2016 http://hdl.handle.net/10852/52339 URN:NBN:no-55554 Fulltext https://www.duo.uio.no/bitstream/handle/10852/52339/1/Master_thesis2016_Henrik_N_Hansen.pdf Master thesis Masteroppgave 2016 ftoslouniv 2020-06-21T08:49:50Z A reservoir characterization of the Stø formation has been performed in two wells linked to the Snøhvit field within the Hammerfest Basin in the South-Western Barents Sea. The reservoir quality of the Stø formation has been described as a function of provenance, depositional environment and diagenesis where both a petrographic- and a petrophysical approach has been implemented. The primary focus has been to investigate processes which have had an influence on the reservoir quality in the Stø formation, with special regard to porosity. Provenance and depositional environment have been of great importance for the resultant reservoir quality within the Stø formation as these processes determined initial rock properties such as mineralogy, sorting and grain size. The mature mineralogy of the Stø formation has been linked to leaching and reworking of the sediments prior to final deposition, whereas the detrital clay content has been related to a transgressive development of the shoreline in a shallow marine setting. IGV results with respect to grain size indicate that intervals consisting of very fine sand had the best preserved porosity after mechanical compaction, whereas the same intervals indicate significant porosity reduction during the chemical compaction regime, due to quartz cementation. Highly cemented intervals have been linked to the distance between stylolites and the relative amounts of micro-stylolites, which is thought to be the most prominent silica dissolving mechanism. A relationship between quartz cement and porosity shows that quartz cementation is the major porosity reducing mechanism at depth within the Stø formation. The lower part of the Stø formation have the best preserved porosity and lies in the range of 8-13%, whereas upper part of the Stø formation have porosity values ranging from 4-14%. However, the majority of the porosity data are below 8% within the upper part of the Stø formation. Authigenic kaolinite and illite has been suggested to have a minor influence on the reservoir quality within the Stø formation, due to the relatively small amounts of these clay minerals compared to the bulk volume. Thin clay laminations were sporadically observed within the upper part of the Stø formation that also is intervals with a high quartz cement volume. These intervals may reduce the vertical permeability. Master Thesis Barents Sea Hammerfest Hammerfest Basin Snøhvit Universitet i Oslo: Digitale utgivelser ved UiO (DUO) Barents Sea Stø ENVELOPE(15.124,15.124,69.019,69.019) |
institution |
Open Polar |
collection |
Universitet i Oslo: Digitale utgivelser ved UiO (DUO) |
op_collection_id |
ftoslouniv |
language |
English |
description |
A reservoir characterization of the Stø formation has been performed in two wells linked to the Snøhvit field within the Hammerfest Basin in the South-Western Barents Sea. The reservoir quality of the Stø formation has been described as a function of provenance, depositional environment and diagenesis where both a petrographic- and a petrophysical approach has been implemented. The primary focus has been to investigate processes which have had an influence on the reservoir quality in the Stø formation, with special regard to porosity. Provenance and depositional environment have been of great importance for the resultant reservoir quality within the Stø formation as these processes determined initial rock properties such as mineralogy, sorting and grain size. The mature mineralogy of the Stø formation has been linked to leaching and reworking of the sediments prior to final deposition, whereas the detrital clay content has been related to a transgressive development of the shoreline in a shallow marine setting. IGV results with respect to grain size indicate that intervals consisting of very fine sand had the best preserved porosity after mechanical compaction, whereas the same intervals indicate significant porosity reduction during the chemical compaction regime, due to quartz cementation. Highly cemented intervals have been linked to the distance between stylolites and the relative amounts of micro-stylolites, which is thought to be the most prominent silica dissolving mechanism. A relationship between quartz cement and porosity shows that quartz cementation is the major porosity reducing mechanism at depth within the Stø formation. The lower part of the Stø formation have the best preserved porosity and lies in the range of 8-13%, whereas upper part of the Stø formation have porosity values ranging from 4-14%. However, the majority of the porosity data are below 8% within the upper part of the Stø formation. Authigenic kaolinite and illite has been suggested to have a minor influence on the reservoir quality within the Stø formation, due to the relatively small amounts of these clay minerals compared to the bulk volume. Thin clay laminations were sporadically observed within the upper part of the Stø formation that also is intervals with a high quartz cement volume. These intervals may reduce the vertical permeability. |
format |
Master Thesis |
author |
Hansen, Henrik Nygaard |
spellingShingle |
Hansen, Henrik Nygaard Reservoir characterization of the Stø formation in the Hammerfest Basin, SW Barents Sea |
author_facet |
Hansen, Henrik Nygaard |
author_sort |
Hansen, Henrik Nygaard |
title |
Reservoir characterization of the Stø formation in the Hammerfest Basin, SW Barents Sea |
title_short |
Reservoir characterization of the Stø formation in the Hammerfest Basin, SW Barents Sea |
title_full |
Reservoir characterization of the Stø formation in the Hammerfest Basin, SW Barents Sea |
title_fullStr |
Reservoir characterization of the Stø formation in the Hammerfest Basin, SW Barents Sea |
title_full_unstemmed |
Reservoir characterization of the Stø formation in the Hammerfest Basin, SW Barents Sea |
title_sort |
reservoir characterization of the stø formation in the hammerfest basin, sw barents sea |
publishDate |
2016 |
url |
http://hdl.handle.net/10852/52339 http://urn.nb.no/URN:NBN:no-55554 |
long_lat |
ENVELOPE(15.124,15.124,69.019,69.019) |
geographic |
Barents Sea Stø |
geographic_facet |
Barents Sea Stø |
genre |
Barents Sea Hammerfest Hammerfest Basin Snøhvit |
genre_facet |
Barents Sea Hammerfest Hammerfest Basin Snøhvit |
op_relation |
http://urn.nb.no/URN:NBN:no-55554 Hansen, Henrik Nygaard. Reservoir characterization of the Stø formation in the Hammerfest Basin, SW Barents Sea. Master thesis, University of Oslo, 2016 http://hdl.handle.net/10852/52339 URN:NBN:no-55554 Fulltext https://www.duo.uio.no/bitstream/handle/10852/52339/1/Master_thesis2016_Henrik_N_Hansen.pdf |
_version_ |
1766370333371138048 |