Reuters: An earthquake with a magnitude of 4.5 that struck near the U.S. crude oil hub of Cushing, Oklahoma on Saturday occurred just days after regulators imposed new rules meant to prevent temblors in the area and said more changes were possible. The Oklahoma Corporation Commission (OCC), which regulates the state's oil and gas industry, ordered companies on Sept. 18 to shut or reduce usage of five saltwater disposal wells around the north-central Oklahoma city of Cushing. Saltwater, a normal byproduct...