Extensive intersecting sets of veins in a dolomitic bed within the organic rich member of the Monterey Formation, Arroyo Burro Beach, near Santa Barbara, California. Such extensive networks of veins are a testament to the tensile state of stress locally acheived due to differences in mechanical properties between different layers within the sequence and the generation of fluid overpressure during diagenisi. Such intersecting fracture sets are served as important conduits for fluid migration in these otherwise relatively impermeable lithologies.