40949
2018
2018
eng
19
postprint
1
2018-04-04
2018-04-04
--
Variability of the geothermal gradient across two differently aged magma-rich continental rifted margins of the Atlantic Ocean
Abstract. The aim of this study is to investigate the shallow thermal field differences for two differently aged passive continental margins by analyzing regional variations in geothermal gradient and exploring the controlling factors for these variations. Hence, we analyzed two previously published 3-D conductive and lithospheric-scale thermal models of the Southwest African and the Norwegian passive margins. These 3-D models differentiate various sedimentary, crustal, and mantle units and integrate different geophysical data such as seismic observations and the gravity field. We extracted the temperature–depth distributions in 1 km intervals down to 6 km below the upper thermal boundary condition. The geothermal gradient was then calculated for these intervals between the upper thermal boundary condition and the respective depth levels (1, 2, 3, 4, 5, and 6 km below the upper thermal boundary condition). According to our results, the geothermal gradient decreases with increasing depth and shows varying lateral trends and values for these two different margins. We compare the 3-D geological structural models and the geothermal gradient variations for both thermal models and show how radiogenic heat production, sediment insulating effect, and thermal lithosphere–asthenosphere boundary (LAB) depth influence the shallow thermal field pattern. The results indicate an ongoing process of oceanic mantle cooling at the young Norwegian margin compared with the old SW African passive margin that seems to be thermally equilibrated in the present day.
the Southwest African and the Norwegian margins
urn:nbn:de:kobv:517-opus4-409493
online registration
Solid Earth 9 (2018) Nr. 1 S. 139-158 DOI: 10.5194/se-9-139-2018
<a href="http://publishup.uni-potsdam.de/opus4-ubp/frontdoor/index/index/docId/40950">Bibliographieeintrag der Originalveröffentlichung/Quelle</a>
CC-BY - Namensnennung 4.0 International
Ershad Gholamrezaie
Magdalena Scheck-Wenderoth
Judith Sippel
Manfred Strecker
Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe
414
eng
uncontrolled
radiogenic heat-production
eng
uncontrolled
European basin system
eng
uncontrolled
lower crustal bodies
eng
uncontrolled
north-atlantic
eng
uncontrolled
subsidence analysis
eng
uncontrolled
sedimentary basins
eng
uncontrolled
tectonic evolution
eng
uncontrolled
Argentine margine
eng
uncontrolled
thermal field
eng
uncontrolled
voring basin
Geowissenschaften
open_access
Institut für Geowissenschaften
Referiert
Open Access
Institut für Erd- und Umweltwissenschaften
Universität Potsdam
https://publishup.uni-potsdam.de/files/40949/pmnr_414.online.pdf
40950
2018
2018
eng
139
158
1
9
article
Copernicus
Göttingen
1
--
2018-02-22
--
Variability of the geothermal gradient across two differently aged magma-rich continental rifted margins of the Atlantic Ocean
Abstract. The aim of this study is to investigate the shallow thermal field differences for two differently aged passive continental margins by analyzing regional variations in geothermal gradient and exploring the controlling factors for these variations. Hence, we analyzed two previously published 3-D conductive and lithospheric-scale thermal models of the Southwest African and the Norwegian passive margins. These 3-D models differentiate various sedimentary, crustal, and mantle units and integrate different geophysical data such as seismic observations and the gravity field. We extracted the temperature–depth distributions in 1 km intervals down to 6 km below the upper thermal boundary condition. The geothermal gradient was then calculated for these intervals between the upper thermal boundary condition and the respective depth levels (1, 2, 3, 4, 5, and 6 km below the upper thermal boundary condition). According to our results, the geothermal gradient decreases with increasing depth and shows varying lateral trends and values for these two different margins. We compare the 3-D geological structural models and the geothermal gradient variations for both thermal models and show how radiogenic heat production, sediment insulating effect, and thermal lithosphere–asthenosphere boundary (LAB) depth influence the shallow thermal field pattern. The results indicate an ongoing process of oceanic mantle cooling at the young Norwegian margin compared with the old SW African passive margin that seems to be thermally equilibrated in the present day.
Solid Earth
the Southwest African and the Norwegian margins
1869-9529
1869-9510
10.5194/se-9-139-2018
PA 1520287193
1785.00
online registration
<a href="http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-409493">Zweitveröffentlichung in der Schriftenreihe Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe ; 414</a>
CC-BY - Namensnennung 4.0 International
Ershad Gholamrezaie
Magdalena Scheck-Wenderoth
Judith Sippel
Manfred Strecker
eng
uncontrolled
radiogenic heat-production
eng
uncontrolled
European basin system
eng
uncontrolled
lower crustal bodies
eng
uncontrolled
north-atlantic
eng
uncontrolled
subsidence analysis
eng
uncontrolled
sedimentary basins
eng
uncontrolled
tectonic evolution
eng
uncontrolled
Argentine margine
eng
uncontrolled
thermal field
eng
uncontrolled
voring basin
Geowissenschaften
Institut für Geowissenschaften
Referiert
Publikationsfonds der Universität Potsdam
Open Access
Institut für Erd- und Umweltwissenschaften