ABSTRACT
The anticlinal structure of oil domes has a counterpart in domical flow layers of salt domes and intrusive domes. The latter commonly possess, in addition to flow layers, flow lines that record directions of maximum lengthening within the planes of flow.
Fracture systems in intrusive domes can be directly correlated with directions of maximum lengthening: cross joints are arranged normal to the flow lines, and may constitute fans, the individual planes dipping into the mass. Other fracture systems show similar relations to the elongation in the plastic stage, and joint systems in oil domes may be interpreted with considerable accuracy if they bear the same relations to the apex of a dome as do the corresponding fractures in intrusive domes. Since they may act as feeders of fuels, or as mineralizing avenues, studies along this line deserve attention.
