Paleomagnetic samples were taken at 194 sites on Hualalai Volcano to obtain characteristic mean remanent magnetic directions using a standard protocol (McElhinny, 1973). Eight (8) to twelve (12) cores were taken at each site with a portable, water-cooled, diamond-coring drill, and oriented in the field exclusively with a suncompass. Measurements were conducted on both a spinner magnetometer and on a cryogenic magnetometer (Butler, 1992). Two trial specimens from each site were progressively demagnetized using a standard alternating-field (AF) protocol to determine the lowest peak-field level that established stable remanent magnetic directions. All remaining specimens from each site were then demagnetized at blanket-field levels (usually 10 – 30mT) shown by the trial specimens to remove all secondary magnetic components. One site was progressively thermally demagnetized to separate a low-T remagnetization from an overlying flow from the high-T original thermoremanent magnetization of an underlying flow. Given the youth of these basaltic eruptive products, there was little evidence of significant secondary magnetization in samples from these sites. Mean directions of remanent magnetization at each site were calculated using Fisher (1953) statistics. All sites record remanent magnetic directions showing normal polarity with virtual geomagnetic pole (VGP) co-latitudes rarely exceeding 15°. A single site (6B775) in an older lava flow shows a well grouped remanent magnetic direction with an anomalous co-latitude of 46° suggesting it erupted during a geomagnetic excursion.
