Figure F24. Examples of high-quality thermal demagnetization data, Expedition 345. A. Most samples displayed stable, high unblocking temperature components of magnetization after removal of drilling-induced components by low-temperature demagnetization (LTD) and of lower temperature components (probably related to alteration in some samples). B. Several samples from Hole U1415J were found to hold complex remanences consisting of two or three nearly antipodal components, suggesting that magnetization was acquired in different geomagnetic polarity periods. Blue arrow = drilling-induced magnetization, red/orange/green arrows = high/middle/low unblocking temperature components, solid circles = projection on to the horizontal plane, open circles = projection on to the vertical y-z plane. Inset is equal-area stereographic projection in B (solid/open symbols = lower/upper hemisphere).
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