Fig. 4
Photomicrographs of paint-cross sections taken from the curtain area, approximately from the locations indicated in Fig. 3a. Sample S1, taken with visible (a) and with UV illumination (b), original magnification ×400; and electron backscattered image detail (c) taken with a ×1063 magnification in the rectangle included in b. The arrow in c indicates the location of a foraminifer. Sample S2, taken with visible (d) and with UV illumination (e), original magnification ×400; and electron backscattered image detail (f) taken with a ×1067 magnification in the rectangle included in e