surgical operation, surgical procedure, surgical process, surgery, operation - a medical procedure involving an incision with instruments; performed to repair damage or arrest disease in a living body; they will schedule the operation as soon as an operating room is available; he died while undergoing surgery.
A quarter mile is, by definition, a fourth of a mile. It is 1,320 feet or 402.3 meters. On a standard-sized Olympic track, it is a little more than a single lap.
The Empty Quarter features a varied topography. The elevation is as high 2,000 feet (610 meters) above sea level in the west and slopes down to about 600 feet (180 meters) in the east. In the western parts of the desert, the sand is fine and soft while the opposite spectrum contains sand dunes, salt flats, and plains of gravel and gypsum.