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Suitability of nonwelded pyroclastic-flow deposits for studies of magnetic secular variation: A test based on deposits emplaced at Mount St. Helens, Washington, in 1980

Richard P. Hoblitt·Richard L. Reynolds·Edwin E. Larson
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Abstract

Paleomagnetic directions obtained from nonwelded pyroclastic-flow deposits that were emplaced at Mount St. Helens, Washington, in 1980 have a precision and accuracy similar to data obtainable from lava flows. It is concluded that nonwelded pyroclastic-flow deposits, like lava flows, are suitable for studies of magnetic secular variation. Although clast rotations apparently caused an “inclination error” in the paleomagnetic directions, the error is a few degrees at most.

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 45.99886962627587° to 46.495556167319506° latitude; -122.54699707031249° to -121.90155029296875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Richard P. Hoblitt, Richard L. Reynolds, Edwin E. Larson. 1985. Suitability of nonwelded pyroclastic-flow deposits for studies of magnetic secular variation: A test based on deposits emplaced at Mount St. Helens, Washington, in 1980. https://doi.org/10.1130/0091-7613(1985)13%3C242%3Asonpdf%3E2.0.co%3B2

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