Figure F247. Demagnetization results from Section 304-U1309D-22R-2. A. Scanned image of archive halves and sketches of the archive and working halves illustrating the principal lithologic and alteration features in the section. Red circles = discrete sample locations. Amph. = amphibole, DIS = digital imaging system, Ps = piece. B. Thermal demagnetization results from a discrete sample in Section 304-U1309D-22R-2 (Piece 1) reveal a reversed polarity characteristic remanent magnetization (ChRM) with a lower stability normal polarity component stable up to temperatures of 520°C. C. AF demagnetization results from the corresponding interval of the archive half. D. Thermal demagnetization results from a discrete sample in the vicinity of later pyroxene-rich vein show a much larger normal polarity overprint (stable to 550°C). AF demagnetization results from both (E) the corresponding archive-half interval and (F) the exterior chip of the discrete sample; both have a high stability component of normal polarity similar to the normal polarity overprint isolated by thermal demagnetization of the discrete sample in D. Open circles = projections of the remanence onto the north-south vertical plane, solid circles = projections of the remanence onto the horizontal plane. NRM = natural remanent magnetization. Note that the ChRM directions have been rotated 180° for comparison between pieces.
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