Occidental Petroleum Corp., Los Angeles, (NYSE: OXY) and XTO Energy Inc., Houston, (NYSE: XTO) plan to acquire working interests in Texas, New Mexico and Colorado from Plains Exploration & Production Co., Houston, (NYSE: PXP) in separate deals for a total of $1.75 billion. Oxy will pay $1.55 billion to acquire 50% of Plains' working interests in the Permian Basin in West Texas and New Mexico. Plains will retain a 50% working interest and Oxy will be operator. XTO will pay $180 million in cash and its 50% working interest in the Big Mac 3-D prospect area on the Texas Gulf Coast. XTO will gain properties in the San Juan Basin in New Mexico and in the Barnett shale in Texas.