Curie depth points and Geothermal heat flow estimates from spectral analysis of magnetic data in the Transantarctic Mountains and Wilkes Subglacial Basin region.

We present Curie depth point (CDP) and geothermal heat flow (GHF) estimations based on spectral analysis of magnetic airborne data for the Transantarctic Mountains (TAM) and Wilkes Subglacial Basin area. The Curie depth point is defined as the depth at which the Curie Temperature of 580 degC is reached. The Curie Temperature describes the temperature at which magnetic minerals lose their ability to generate a strong magnetic field.

We use exclusively high resolution magnetic airborne measurements from the ADMAP-2 compilation, where we have removed data with a 15 km blanking distance threshold to reported flight lines to minimise artefact from interpolation. The obtained magnetic dataset is upward continued to a constant station height of 4 km and subdivided into window with a window size of 200 km, 300 km, and 400 km. For each window we calculate the power spectrum and estimate the CDP from the power spectrum. Subsequently we estimate the magnetic data coverage for each window and discard CDP estimates for window below a data coverage threshold of 80%. From the CDP interface GHF is forward calculated assuming constant thermal conductivity for the crust and a constant temperature at the base of the ice sheet representing the pressure melting point. This study is motivated by the need of high resolution GHF models form the Icesheet modelling community especially in marine based Basins like the Wilkes Subglacial Basin as well as by interpretation of the origin of the Transantarctic Mountains. Recent seismic studies have argued that warmer west Antarctic is present beneath the Transantarctic Mountains, which give thermal support to the mountains range. This hypothesis should lead to increased GHF in the area and therefore can be tested against our GHF model. Our results show elevated heat flow in the area of the Transantarctic mountains supporting the idea of thermal support for the mountain range with an independent method. Furthermore, we image elevate heat flow in the central Basin of the Wilks Subglacial Basin and Rennick Graben which have not been imaged before by continent wide GHF models.

Funding for this research was provided by NERC through a SENSE CDT studentship (NE/T00939X/1)

Alternate title: Polar Data Centre (PDC) record GB/NERC/BAS/PDC/01669

Date (Publication): 2022-09-21

Citation identifier: http://www.antarctica.ac.uk/dms/metadata.php?id= / GB/NERC/BAS/PDC/01669

Point of contact

Organisation name	Individual name	Electronic mail address	Role
British Antarctic Survey		pdc@bas.ac.uk	Custodian
NERC EDS UK Polar Data Centre	Lowe, M., Mather, B., Green, C., Jordan, T., Ebbing, J., & Larter, R.	pdc@bas.ac.uk	Originator

Maintenance and update frequency: Unknown

Keywords

NDGO0001

NERC OAI Harvesting

NERC_DDC

GCMD Parameter Valids

EARTH SCIENCE > Solid Earth > Geomagnetism > Magnetic Anomalies
EARTH SCIENCE > Solid Earth > Geothermal

BAS Free-text keywords

Antarctica
Curie depth point
Geothermal heat flow
Transantarctic Mountains
Wilkes Subglacial Basin
spectral analysis of magnetic data

Use limitation: This data is covered by a UK Open Government Licence ( http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/)

Please cite this dataset as follows:

Lowe, M., Mather, B., Green, C., Jordan, T., Ebbing, J., & Larter, R. (2022). Curie depth points and Geothermal heat flow estimates from spectral analysis of magnetic data in the Transantarctic Mountains and Wilkes Subglacial Basin region. (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/B8DCBAA9-3AC0-42BD-95A5-6B5961CBCB7E

Access constraints: Other restrictions

Other constraints: This data is covered by a UK Open Government Licence ( http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/)

Please cite this dataset as follows:

Lowe, M., Mather, B., Green, C., Jordan, T., Ebbing, J., & Larter, R. (2022). Curie depth points and Geothermal heat flow estimates from spectral analysis of magnetic data in the Transantarctic Mountains and Wilkes Subglacial Basin region. (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/B8DCBAA9-3AC0-42BD-95A5-6B5961CBCB7E

Language: English

Topic category

Geoscientific information

Begin date: 2022-05-10

End date: 2022-05-12

Reference system identifier: OGP / urn:ogc:def:crs:EPSG::4326

Distribution format

Distributor contact

Organisation name	Individual name	Electronic mail address	Role
Polar Data Centre - British Antarctic Survey		pdc@bas.ac.uk	Distributor

OnLine resource

Protocol	Linkage	Name
http	https://ramadda.data.bas.ac.uk/repository/entry/show?entryid=b8dcbaa9-3ac0-42bd-95a5-6b5961cbcb7e	GET DATA

Hierarchy level: Dataset

Domain consistency

Measure identification: INSPIRE / Conformity_001

Conformance result

Title: INSPIRE Data Specification on unknown theme Guidelines

Date

Explanation: See the referenced specification

Pass: No

Statement: Uncertainty estimates of the CDP and GHF estimates are provided in the data files. The uncertainty for the CDP ranges from 2 km to 8 km throughout the study area. GHF uncertainties range from 2.9 mW/m2 to 48.8 mW/m2. In depth discussion on the uncertainty of the results are presented in the associated publication in JGR Solid Earth.