What was found
DURING OUR INITIAL DESCENT, AROUND 36,00 FEET, WE COULD FEE A CHANGE IN PRESSURIZATION. I LOOKED AT THE PRESSURE CONTROLLER AND SAW THAT THERE WAS A RATE OF CHANGE OF -2500 FEET PER MINUTE (CABIN PRESSURE RISING). IT ALSO INDICATED THAT OUR CURRENT CABIN PRESSURE WAS APPROXIMATELY 8000 FEE AND CLIMBING. IT WOULD TYPICALLY BE BETWEEN 6 AND 7000 FEET. COMMUNICATED TO CENTER CONTROL THAT WE NEEDED AN IMMEDIATE DESCENT DUE TO A PROBLEM WITH OUR PRESSURIZATION SYSTEM. WE HAD A NORMAL APPROACH AND LANDING AT MEMPHIS WITHOUT FURTHER PROBLEMS.