Figure F5. A. Magnetostratigraphy and characteristic directions from Eocene–Cretaceous in Holes 1257A, 1257B, and 1257C based on analysis of discrete samples. The majority of the minicores are from Hole 1257B, with enhanced Maastrichtian–Campanian from Holes 1257A and 1257C. The measured data from the three holes have been merged using the composite depth scale, and these adjustments are shown schematically for each hole (rightmost columns). Polarity ratings are graded according to reliability and number of vectors utilized in the characteristic direction (R = reliable reversed polarity, INT = indeterminate, N = reliable normal polarity; and relative placement of other points indicates degree of precision or uncertainty). Polarity zones are assigned according to clusters of individual polarity interpretations. Normal polarity zones = dark gray, reversed polarity zones = white, and uncertain polarity or gaps in data coverage = cross hatched. Assignments of polarity chrons are based on the polarity zone pattern and the constraints from microfossil biostratigraphy. B. Holes 1258A and 1258B (Eocene–Cretaceous). C. Holes 1259A and 1259B (Eocene–Cretaceous). D. Holes 1260A and 1260B (middle Eocene–Campanian and Albian). E. Holes 1261A and 1261B (middle Eocene–Campanian).