The Balcones fault zone is a system of en echelon normal faults that extends from about 20 mi. N. of Del Rio to a short distance N. of Waco, Texas. Recent field work has shown large normal faults, with displacements up to 100 ft., in NE. Ellis County (between Waco and Dallas). These faults are probably part of the Balcones fault system because 1) they lie along a northeastward projection of the Balcones zone, 2)they have the trend (NE. strike) and the order of magnitude of the northern Balcones faults, and 3) they are about 30 mi. W. of faults in the Luling-Mexia fault system.