SEA LEVEL CHANGES AND MARGINAL SUBMARINE CHANNELLING IN THE MIDDLE PENNSYLVANIAN LA TUNA FORMATION OF WEST TEXAS AND SOUTHERN NEW MEXICO

The Middle Pennsylvanian La Tuna Formation of west Texas and southern New Mexico is a complex shelf and slope carbonate that reflects the complicated sea level changes present during the Middle Pennsylvanian. These changes are tectonic and glacial eustatic. The La Tuna outcrops on the north Franklin Mountains around the Texas – New Mexico state line show varying scales of channelization and refilling with both transported and locally developed carbonates. The channels are up to over one half kilometer in width, and their measurements are limited by the size rotated block of the Franklins.