Interpretation of Mars southern highlands high amplitude magnetic field with total gradient and fractal source modeling: New insights into the magnetic mystery of Mars

Research output: Contribution to journalArticlepeer-review

15 Scopus citations

Abstract

Using model studies, the total gradient (TG) of the Z-component magnetic field is shown to be a useful quantity for delineating sources of satellite-altitude magnetic anomalies; this field is used to constrain the location and lateral boundaries of sources of high amplitude magnetic anomalies of southern highlands of Mars. The TG field suggests two parallel linear and oppositely magnetized sources of 1000 and 1800 km length separated by 1000 km of region of intervening non-parallel sources. The simplest interpretation of the long, linear features is that they are zones of multitudinous crustal scale dikes formed in separate episodes of rifting, and not features associated with the mechanism of seafloor spreading. Forward modeling with uniformly magnetized sources suggests that magnetizations of the order of 10-50 A/m (40 km thickness) over ∼100 km width in the case of the southern source and of 12.5-27.5. A/m (40 km thickness) and ∼200 km width for the northern source are necessary to explain the Z-component amplitudes and features of the TG field. If the crustal magnetization on Mars were to be distributed fractally as on Earth, magnetizations matching the largest amplitude features on Mars may be spatially correlated from a 50-100 km distance range (β∼. 3) to approaching nearly uniform magnetization (β∼. 5) values. To keep magnetization intensity as small as possible, the higher end of β values are preferred, whereas, small amplitude anomaly features could be generated from sources with β∼. 3. Many of the Mars anomaly features could be coalescence effects similar to the coalescence of anomaly features observed on http://icarus.cornell.edu/information/keywords.html.Earth.

Original languageEnglish
Pages (from-to)400-412
Number of pages13
JournalIcarus
Volume214
Issue number2
DOIs
StatePublished - Aug 2011

Bibliographical note

Funding Information:
The author is grateful to Jeffrey Miller and Saurav Biswas for discussions and earlier versions of model studies of this research. The author thanks all of the Mars researchers with whom he has had discussions on these topics; they are too numerous to acknowledge individually here. Mario Acuña is remembered fondly for his openness to different valid interpretations. Helpful comments of Lon Hood, Mike Purucker, Donna Jurdy, David Clark and anonymous reviewers improved the manuscript significantly. Much of the early work in this study was supported by an MDAP grant from NASA with Patrick Taylor—none of this would have been possible without that support. The author greatly appreciates the spousal hospitality of the Rockefeller Foundation’s Bellagio Center — its idyllic setting afforded the clarity of thinking needed to reembark on this paper.

Keywords

  • Magnetic fields
  • Mars
  • Mars, interior
  • Mineralogy
  • Tectonics
  • Terrestrial planets

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Fingerprint

Dive into the research topics of 'Interpretation of Mars southern highlands high amplitude magnetic field with total gradient and fractal source modeling: New insights into the magnetic mystery of Mars'. Together they form a unique fingerprint.

Cite this