Plate 1a.: Dolomicrite filling F1 vein contains fragments of brecciated siliceous dolostone. Stratification of dolomicrite vein fill (arrow) is parallel to bedding indicating vein filling prior to regional folding and tilting of bedding by 55°. F1 dolomicrite veins are partly reactivated by F4 calcite veins (white) that extend into over- and underlying mudstone and porcelanite beds. Scale is 22 cm. Arroyo Burro Beach.