Ultra-high sensitivity moment magnetometry of geological samples using magnetic microscopy
Useful paleomagnetic information is expected to be recorded by samples with moments up to three orders of magnitude below the detection limit of standard superconducting rock magnetometers. Such samples are now detectable using recently developed magnetic microscopes, which map the magnetic fields a...
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
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American Geophysical Union (AGU)
2017
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| Online Access: | http://hdl.handle.net/1721.1/108020 https://orcid.org/0000-0003-3113-3415 |
| _version_ | 1811070139771125760 |
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| author | Lima, Eduardo A. Weiss, Benjamin P. |
| author2 | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences |
| author_facet | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Lima, Eduardo A. Weiss, Benjamin P. |
| author_sort | Lima, Eduardo A. |
| collection | MIT |
| description | Useful paleomagnetic information is expected to be recorded by samples with moments up to three orders of magnitude below the detection limit of standard superconducting rock magnetometers. Such samples are now detectable using recently developed magnetic microscopes, which map the magnetic fields above room-temperature samples with unprecedented spatial resolutions and field sensitivities. However, realizing this potential requires the development of techniques for retrieving sample moments from magnetic microscopy data. With this goal, we developed a technique for uniquely obtaining the net magnetic moment of geological samples from magnetic microscopy maps of unresolved or nearly unresolved magnetization. This technique is particularly powerful for analyzing small, weakly magnetized samples such as meteoritic chondrules and terrestrial silicate crystals like zircons. We validated this technique by applying it to field maps generated from synthetic sources and also to field maps measured using a superconducting quantum interference device (SQUID) microscope above geological samples with moments down to 10⁻¹⁵ Am². For the most magnetic rock samples, the net moments estimated from the SQUID microscope data are within error of independent moment measurements acquired using lower sensitivity standard rock magnetometers. In addition to its superior moment sensitivity, SQUID microscope net moment magnetometry also enables the identification and isolation of magnetic contamination and background sources, which is critical for improving accuracy in paleomagnetic studies of weakly magnetic samples. |
| first_indexed | 2024-09-23T08:27:22Z |
| format | Article |
| id | mit-1721.1/108020 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T08:27:22Z |
| publishDate | 2017 |
| publisher | American Geophysical Union (AGU) |
| record_format | dspace |
| spelling | mit-1721.1/1080202024-05-15T03:18:16Z Ultra-high sensitivity moment magnetometry of geological samples using magnetic microscopy Lima, Eduardo A. Weiss, Benjamin P. Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Weiss, Benjamin P Useful paleomagnetic information is expected to be recorded by samples with moments up to three orders of magnitude below the detection limit of standard superconducting rock magnetometers. Such samples are now detectable using recently developed magnetic microscopes, which map the magnetic fields above room-temperature samples with unprecedented spatial resolutions and field sensitivities. However, realizing this potential requires the development of techniques for retrieving sample moments from magnetic microscopy data. With this goal, we developed a technique for uniquely obtaining the net magnetic moment of geological samples from magnetic microscopy maps of unresolved or nearly unresolved magnetization. This technique is particularly powerful for analyzing small, weakly magnetized samples such as meteoritic chondrules and terrestrial silicate crystals like zircons. We validated this technique by applying it to field maps generated from synthetic sources and also to field maps measured using a superconducting quantum interference device (SQUID) microscope above geological samples with moments down to 10⁻¹⁵ Am². For the most magnetic rock samples, the net moments estimated from the SQUID microscope data are within error of independent moment measurements acquired using lower sensitivity standard rock magnetometers. In addition to its superior moment sensitivity, SQUID microscope net moment magnetometry also enables the identification and isolation of magnetic contamination and background sources, which is critical for improving accuracy in paleomagnetic studies of weakly magnetic samples. National Science Foundation (U.S.) (DMS-1521765) National Science Foundation (U.S.) (DMS-0934689) Peterson, Thomas F. 2017-04-10T18:09:39Z 2017-04-10T18:09:39Z 2016-10 2016-06 Article http://purl.org/eprint/type/JournalArticle 1525-2027 http://hdl.handle.net/1721.1/108020 Lima, Eduardo A. and Weiss, Benjamin P.“Ultra-High Sensitivity Moment Magnetometry of Geological Samples Using Magnetic Microscopy.” Geochemistry, Geophysics, Geosystems 17, no. 9 (September 2016): 3754–3774. https://orcid.org/0000-0003-3113-3415 en_US http://dx.doi.org/10.1002/2016GC006487 Geochemistry, Geophysics, Geosystems Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf American Geophysical Union (AGU) arXiv |
| spellingShingle | Lima, Eduardo A. Weiss, Benjamin P. Ultra-high sensitivity moment magnetometry of geological samples using magnetic microscopy |
| title | Ultra-high sensitivity moment magnetometry of geological samples using magnetic microscopy |
| title_full | Ultra-high sensitivity moment magnetometry of geological samples using magnetic microscopy |
| title_fullStr | Ultra-high sensitivity moment magnetometry of geological samples using magnetic microscopy |
| title_full_unstemmed | Ultra-high sensitivity moment magnetometry of geological samples using magnetic microscopy |
| title_short | Ultra-high sensitivity moment magnetometry of geological samples using magnetic microscopy |
| title_sort | ultra high sensitivity moment magnetometry of geological samples using magnetic microscopy |
| url | http://hdl.handle.net/1721.1/108020 https://orcid.org/0000-0003-3113-3415 |
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