Constraints on the Source of the Martian Magnetic Anomalies Inferred From Relaxation Time of Remanent Magnetization
Year: 2018
Type: article
Abstract: The strong magnetic anomalies observed over Mars originate from remanence of deep crust, which should be preserved during 4 billion years. We estimate the relaxation time of remanence carried by various types of magnetite, considering temperature and pressure dependences of magnetic parameters. The estimation shows that acicular‐shaped single‐domain magnetite is needed to retain the thick magnetized layer during 4 billion years in a low‐Urey ratio scenario, whereas acicular‐shaped single‐domain, equidimensional single‐domain, and pseudo‐single‐domain magnetites can be the source of anomalies in a high‐Urey ratio scenario. In each case, fine‐grained (<10 μm) and preferably high‐aspect‐ratio magnetite in deep crust is needed to explain the observed anomalies.
Source: Geophysical Research Letters
DOI: 10.1029/2018gl077498
Institutions: Tokyo Institute of Technology, The University of Tokyo, University of Kochi, Marine Core Research Institute, Kochi University, Kōchi University, Doshisha University, Kumamoto University, Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology, Japan Agency for Marine-Earth Science and Technology
Language: English
Subfield: Geophysics
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2803150352