Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 6 April 1979:
Vol. 204. no. 4388, pp. 53 - 57
DOI: 10.1126/science.204.4388.53
Prev | Table of Contents | Next

Articles

The Moon: Sources of the Crustal Magnetic Anomalies

L. L. HOOD 1, P. J. COLEMAN JR. 1, and D. E. WILHELMS 2

1 Institute of Geophysics and Planetary Physics, University of California, Los Angeles 90024
2 U.S. Geological Survey, Menlo Park, California 94025

Previously unmapped Apollo 16 subsatellite magnetometer data collected at low altitudes over the lunar near side are presented. Medium-amplitude magnetic anomalies exist over the Fra Mauro and Cayley Formations (primary and secondary basin ejecta emplaced 3.8 to 4.0 billion years ago) but are nearly absent over the maria and over the craters Copernicus, Kepler, and Reiner and their encircling ejecta mantles. The largest observed anomaly (radial component sim21 gammas at an altitude of 20 kilometers) is exactly correlated with a conspicuous light-colored deposit on western Oceanus Procellarum known as Reiner ggr. Assuming that the Reiner ggr deposit is the source body and estimating its maximum average thickness as 10 meters, a minimum mean magnetization level of 5.2 ± 2.4 x 10–2 electromagnetic units per gram, or sim500 times the stable magnetization component of the most magnetic returned sample, is calculated. An age for its emplacement of le 2.9 billion years is inferred from photogeologic evidence, implying that magnetization of lunar crustal materials must have continued for a period exceeding 1 billion years.

Submitted on December 5, 1978


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Lunar Magnetic Anomalies and Surface Optical Properties.
L. L. Hood, L. L. HOOD, and G. SCHUBERT (1980)
Science 208, 49-51
   Abstract »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)