Dating recent Hawaiian lava flows using paleomagnetic secular variation

Author:

Holcomb, R. T., Chapman, D. E., McWilliams, M. O.

Title:

Dating recent Hawaiian lava flows using paleomagnetic secular variation

Periodical:

Geological Society of America Bulletin

Year:

1986

Volume:

97

Pages:

829-839

Subject:

Geomagnetism secular variations Geomagnetic field inclination

Summary:

Hawaiian paleomagnetic secular variation (SV) is defined from samples at 67 sites on lava flows of known age. Paleomagnetic directions range through 40 degrees of inclination and 30 degrees of declination; angular dispersion within sites is commonly less than 2 degrees. The average SV rate in the past 200 yr has been 4.5 degrees/century. Dating precision is limited by dispersion of 4.5 degrees among sites of similar age. The main dispersion sources are in (super 14)C dates (3.0 degrees), intra-flow deformations (2.0 degrees), and local magnetic anomalies (1.5 degrees). Results from 68 sites on undated flows show that 95% of Kilauea's surface is younger than 1,000 yr. Averaging of available data yields an SV reference curve which is fairly reliable to ~1,500 yr ago, contains gaps and ambiguities 1,500-3,000 yr ago, and remains highly uncertain 3,000-6,000 yr ago.

Label:

Geology

URL:

http://cletus.uhh.hawaii.edu:2074/10.1130/0016-7606(1986)97<829:DRHLFU>2.0.CO;2

Date:

July 1986

Collection:

Periodicals