Paleointensity of the ancient Martian magnetic field

Mars today has no core dynamo magnetic field. However, the discovery of remanent magnetization in Martian meteorites and intense crustal magnetization suggests that Mars once had a global field. Here we present high resolution maps of the magnetic field of Martian meteorite ALH 84001. These maps are the most sensitive yet quantitative study of natural remanent magnetization (with resolved anomalies as weak as 1 × 10−14 Am2). ALH 84001 likely contains a 4 billion year old (Ga) thermoremanence partially overprinted by one or more poorly understood secondary components. Our data suggest that the paleointensity of the local paleofield was within an order of magnitude of that of the present‐day Earth. If this field were global in extent, it should have played a key role in Martian atmospheric and climatic evolution. However, it is still too weak to easily explain the intensity of Martian crustal paleomagnetic anomalies.

[1]  E. A. Lima,et al.  Paleointensity of the Earth's magnetic field using SQUID microscopy , 2007 .

[2]  E. A. Lima,et al.  Paleomagnetic analysis using SQUID microscopy , 2007 .

[3]  A. Steele,et al.  Comprehensive imaging and Raman spectroscopy of carbonate globules from Martian meteorite ALH 84001 and a terrestrial analogue from Svalbard , 2007 .

[4]  J. Gee,et al.  A linear field dependence of thermoremanence in low magnetic fields , 2007 .

[5]  M. S. Bell,et al.  Experimental shock decomposition of siderite and the origin of magnetite in Martian meteorite ALH 84001 , 2007 .

[6]  P. Reiners,et al.  High-temperature Mars-to-Earth transfer of meteorite ALH84001 , 2006 .

[7]  Yongjae Yu How accurately can NRM/SIRM determine the ancient planetary magnetic field intensity? , 2006 .

[8]  D. J. Barber,et al.  Shock and thermal history of Martian meteorite Allan Hills 84001 from transmission electron microscopy , 2006 .

[9]  G. Consolmagno,et al.  An impact origin for the foliation of chondrites , 2005 .

[10]  E. A. Lima,et al.  High-resolution room-temperature sample scanning superconducting quantum interference device microscope configurable for geological and biomagnetic applications , 2005 .

[11]  M. Funaki,et al.  Matching Martian crustal magnetization and magnetic properties of Martian meteorites , 2005 .

[12]  B. Weiss,et al.  Martian Surface Paleotemperatures from Thermochronology of Meteorites , 2005, Science.

[13]  Pierre Rochette,et al.  Toward a robust normalized magnetic paleointensity method applied to meteorites , 2004 .

[14]  Tomas Kohout,et al.  An empirical scaling law for acquisition of thermoremanent magnetization , 2004 .

[15]  B. Ivanov,et al.  Launch of martian meteorites in oblique impacts , 2004 .

[16]  Mohan Sankaran,et al.  Magnetic tests for magnetosome chains in Martian meteorite ALH84001. , 2004, Proceedings of the National Academy of Sciences of the United States of America.

[17]  F. Wellstood,et al.  Position noise in scanning superconducting quantum interference device microscopy , 2004 .

[18]  E. Scott,et al.  Paleomagnetic record of Martian meteorite ALH84001 , 2003 .

[19]  S. Stewart,et al.  Temperatures on Mars from 40Ar/39Ar thermochronology of ALH84001 , 2002 .

[20]  J. Eiler,et al.  Two populations of carbonate in ALH84001: geochemical evidence for discrimination and genesis , 2002 .

[21]  Joseph L. Kirschvink,et al.  Records of an ancient Martian magnetic field in ALH84001 , 2001 .

[22]  J. Gee,et al.  The effect of remanence anisotropy on paleointensity estimates: a case study from the Archean Stillwater Complex , 2000 .

[23]  J P Wikswo,et al.  A low temperature transfer of ALH84001 from Mars to Earth. , 2000, Science.

[24]  H. Wiesmann,et al.  The age of the carbonates in martian meteorite ALH84001. , 1999, Science.

[25]  M. R. Baer Computational modeling of heterogeneous reactive materials at the mesoscale , 1999 .

[26]  F. Ryerson,et al.  The temperature of formation of carbonate in Martian meteorite ALH84001: constraints from cation diffusion , 1999 .

[27]  M. Grady,et al.  The fusion crusts of stony meteorites: Implications for the atmospheric reprocessing of extraterrestrial materials , 1999 .

[28]  Ness,et al.  Global distribution of crustal magnetization discovered by the mars global surveyor MAG/ER experiment , 1999, Science.

[29]  Ness,et al.  Magnetic lineations in the ancient crust of mars , 1999, Science.

[30]  A. Treiman The history of Allan Hills 84001 revised: Multiple shock events , 1998, Meteoritics & planetary science.

[31]  D. Kring,et al.  Formation and relative ages of maskelynite and carbonate in ALH84001 , 1998 .

[32]  D. Collinson Magnetic properties of Martian meteorites: Implications for an ancient Martian magnetic field , 1997 .

[33]  Joseph L. Kirschvink,et al.  Paleomagnetic Evidence of a Low-Temperature Origin of Carbonate in the Martian Meteorite ALH84001 , 1997, Science.

[34]  N. Baydemir Paleointensity of the Earth's Magnetic Field Determined From Miocene (?) - Pliocene Aged Rocks of Mesudiye (Ordu) Region , 1996, Turkish Journal of Earth Sciences.

[35]  C. Eastoe,et al.  Isotopic composition of carbonates in the SNC meteorites Allan Hills 84001 and Nakhla , 1995 .

[36]  H. Wiesmann,et al.  "Martians" Young and Old:" Zagami and ALH 84001 , 1995 .

[37]  Robert L. Parker,et al.  A theory of ideal bodies for seamount magnetism , 1991 .

[38]  F. Hrouda Magnetic anisotropy of rocks and its application in geology and geophysics , 1982 .

[39]  P. O'Brien,et al.  A test for randomness. , 1976, Biometrics.

[40]  R. Butler Natural remanent magnetization and thermomagnetic properties of the Allende meteorite , 1972 .

[41]  R. Wilson Palaeomagnetism and rock magnetism , 1966 .

[42]  G. S. Watson,et al.  A Test for Randomness of Directions , 1956 .

[43]  A. Graham Elements of De Vico's Fifth Comet , 1846 .

[44]  M. Fuller,et al.  Paleomagnetism and rock magnetism of martian meteorite ALH 84001 , 2002 .

[45]  Tesfaye Kidane,et al.  AF demagnetization characteristics of NRM, compared with anhysteretic and saturation isothermal remanence: an aid in the interpretation of NRM , 2002 .

[46]  D. Strangway,et al.  A paleomagnetic conglomerate test using the Abee E4 meteorite , 1983 .