Seismic Interpretation of Sill-Complexes in Sedimentary Basins: The ‘Sub-Sill Imaging Problem’
Application of 3D-seismic reflection-data to igneous systems in sedimentary basins has led to a revolution in the understanding of mafic sill-complexes. However, there is considerable uncertainty on how geometries and architecture of sill complexes within the subsurface relates those imaged in seism...
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ftdatacite:10.17605/osf.io/jfs9x 2023-05-15T16:03:50+02:00 Seismic Interpretation of Sill-Complexes in Sedimentary Basins: The ‘Sub-Sill Imaging Problem’ Eide, Christian Schofield, Nick Lecomte, Isabelle Buckley, Simon Howell, John 2017 https://dx.doi.org/10.17605/osf.io/jfs9x https://doi.org/10.31223/osf.io/jfs9x unknown EarthArXiv https://dx.doi.org/10.1144/jgs2017-096 Academic Free License (AFL) 3.0 Geophysics and Seismology Volcanology Earth Sciences Physical Sciences and Mathematics Geology FOS Earth and related environmental sciences Preprint Text article-journal ScholarlyArticle 2017 ftdatacite https://doi.org/10.17605/osf.io/jfs9x 2021-11-05T12:55:41Z Application of 3D-seismic reflection-data to igneous systems in sedimentary basins has led to a revolution in the understanding of mafic sill-complexes. However, there is considerable uncertainty on how geometries and architecture of sill complexes within the subsurface relates those imaged in seismic reflection-data. To provide constraints on how sill complexes in seismic data should be interpreted, we present synthetic seismograms generated from a seismic-scale (22x0.25 km) outcrop in East Greenland constrained by abundant field-data.This study highlights how overlying igneous rocks adversely affect imaging of underlying intrusions and rocks by decreasing seismic amplitude, frequency and making steeply dipping features near-impossible to image. Furthermore, seismic modelling shows that because of the high impedance contrast between siliciclastic host rock and dolerites, thin (< 5m) intrusions should in principle be imaged at relatively high amplitudes. This is contrary to many published ‘rules of thumb’ for seismic detectability of sill intrusions. However, actual seismic data combined with well-data shows significant amounts of un-imaged sill intrusions, and this is likely due to limited resolution, overburden complexity, poor velocity-models, and interference between closely spaced sill-splays. Significant improvements could be made by better predicting occurrence and geometry of sill intrusions and including these in velocity models. Report East Greenland Greenland DataCite Metadata Store (German National Library of Science and Technology) Greenland Thumb ENVELOPE(-64.259,-64.259,-65.247,-65.247) |
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Open Polar |
collection |
DataCite Metadata Store (German National Library of Science and Technology) |
op_collection_id |
ftdatacite |
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topic |
Geophysics and Seismology Volcanology Earth Sciences Physical Sciences and Mathematics Geology FOS Earth and related environmental sciences |
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Geophysics and Seismology Volcanology Earth Sciences Physical Sciences and Mathematics Geology FOS Earth and related environmental sciences Eide, Christian Schofield, Nick Lecomte, Isabelle Buckley, Simon Howell, John Seismic Interpretation of Sill-Complexes in Sedimentary Basins: The ‘Sub-Sill Imaging Problem’ |
topic_facet |
Geophysics and Seismology Volcanology Earth Sciences Physical Sciences and Mathematics Geology FOS Earth and related environmental sciences |
description |
Application of 3D-seismic reflection-data to igneous systems in sedimentary basins has led to a revolution in the understanding of mafic sill-complexes. However, there is considerable uncertainty on how geometries and architecture of sill complexes within the subsurface relates those imaged in seismic reflection-data. To provide constraints on how sill complexes in seismic data should be interpreted, we present synthetic seismograms generated from a seismic-scale (22x0.25 km) outcrop in East Greenland constrained by abundant field-data.This study highlights how overlying igneous rocks adversely affect imaging of underlying intrusions and rocks by decreasing seismic amplitude, frequency and making steeply dipping features near-impossible to image. Furthermore, seismic modelling shows that because of the high impedance contrast between siliciclastic host rock and dolerites, thin (< 5m) intrusions should in principle be imaged at relatively high amplitudes. This is contrary to many published ‘rules of thumb’ for seismic detectability of sill intrusions. However, actual seismic data combined with well-data shows significant amounts of un-imaged sill intrusions, and this is likely due to limited resolution, overburden complexity, poor velocity-models, and interference between closely spaced sill-splays. Significant improvements could be made by better predicting occurrence and geometry of sill intrusions and including these in velocity models. |
format |
Report |
author |
Eide, Christian Schofield, Nick Lecomte, Isabelle Buckley, Simon Howell, John |
author_facet |
Eide, Christian Schofield, Nick Lecomte, Isabelle Buckley, Simon Howell, John |
author_sort |
Eide, Christian |
title |
Seismic Interpretation of Sill-Complexes in Sedimentary Basins: The ‘Sub-Sill Imaging Problem’ |
title_short |
Seismic Interpretation of Sill-Complexes in Sedimentary Basins: The ‘Sub-Sill Imaging Problem’ |
title_full |
Seismic Interpretation of Sill-Complexes in Sedimentary Basins: The ‘Sub-Sill Imaging Problem’ |
title_fullStr |
Seismic Interpretation of Sill-Complexes in Sedimentary Basins: The ‘Sub-Sill Imaging Problem’ |
title_full_unstemmed |
Seismic Interpretation of Sill-Complexes in Sedimentary Basins: The ‘Sub-Sill Imaging Problem’ |
title_sort |
seismic interpretation of sill-complexes in sedimentary basins: the ‘sub-sill imaging problem’ |
publisher |
EarthArXiv |
publishDate |
2017 |
url |
https://dx.doi.org/10.17605/osf.io/jfs9x https://doi.org/10.31223/osf.io/jfs9x |
long_lat |
ENVELOPE(-64.259,-64.259,-65.247,-65.247) |
geographic |
Greenland Thumb |
geographic_facet |
Greenland Thumb |
genre |
East Greenland Greenland |
genre_facet |
East Greenland Greenland |
op_relation |
https://dx.doi.org/10.1144/jgs2017-096 |
op_rights |
Academic Free License (AFL) 3.0 |
op_doi |
https://doi.org/10.17605/osf.io/jfs9x |
_version_ |
1766399526966394880 |