Strength of the geomagnetic field in the Cretaceous Normal Superchron; new data from submarine basaltic glass of the Troodos Ophiolite

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doi: 10.1029/2003GC000635
Author(s): Tauxe, Lisa; Staudigel, Hubert
Author Affiliation(s): Primary:
Scripps Institution of Oceanography, Geosciences Research Division, La Jolla, CA, United States
Volume Title: Geochemistry, Geophysics, Geosystems - G<sup>3</sup>
Source: Geochemistry, Geophysics, Geosystems - G>3`, Vol.5. Publisher: American Geophysical Union and The Geochemical Society, United States. ISSN: 1525-2027
Note: In English. Accessed on July 15, 2004. 54 refs.; illus., incl. 1 table, sketch map
Summary: We present here new paleointensity data from 39 sampling sites collected from the quenched margins of pillow lavas and dikes exposed within the Troodos Ophiolite (∼92 Ma), formed during the Cretaceous Normal Superchron (CNS), a period of approximately 40 million years when the geomagnetic field reversed extremely infrequently if at all. Monte Carlo simulations suggest that a minimum of 25 estimates are necessary for a reasonably robust estimate for the average field strength. Our data suggest a dipole strength equivalent to the present field or nearly twice the post-CNS average. The mean and standard deviation of the dipole moment (81±43 ZAm2; Z = 1021) from the 57 data points compiled here agree remarkably well with those predicted from the long paleointensity record derived from DSDP Site 522. The new data set for the CNS suggests a picture of a strong and stable field during the period of time when it stopped reversing. Moreover, the similarity of the CNS data with the present geomagnetic field suggests that it is presently in a state of unusual polarity stability
Year of Publication: 2004
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
Key Words: 17 Geophysics, General; Asia; Basalts; Cretaceous; Cretaceous Normal Superchron; Cyprus; DSDP Site 522; Deep Sea Drilling Project; Glasses; IPOD; Igneous rocks; Instruments; Lava; Leg 73; Magnetic field; Magnetic intensity; Magnetic properties; Mesozoic; Middle East; Monte Carlo analysis; Paleointensity; Paleomagnetism; Pillow lava; Secular variations; Statistical analysis; Techniques; Troodos Massif; Troodos Ophiolite; Volcanic rocks
Coordinates: N343000 N354000 E0343000 E0323000
Record ID: 2005016790
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