Figure 3
From: Exceptional sulfur and iron isotope enrichment in millimetre-sized, early Palaeozoic animal burrows
Sedimentologic context of pyrite formation in the Beach Formation. (A) shows moderately bioturbated mudstone composed of millimetre-thick beds with eroded tops. Much of the bioturbated mudstone exhibits deformed bedding and lamination due to animal locomotion (i.e., sediment swimming) in water-rich, non-compacted (possibly fluid?) mud. (B) shows the X-ray image of an enlarged subset of (A). This portion shows that the analyzed mudstone contains pervasive, vertically oriented, zigzagging, meandering pyritic trails and tubular structures (see Fig. 4 for more detail).
