There is a parking lot thatin the base coverd with river rock and on the surface with round gravel .the problem is whe cars go park there stuck and gravel and river rock run away the tires spinning,.

That is not a good combination of parking area since you will almost always get tire spin. You need small compacted stone, usually sold as crush N run or crusher run. It is put in at about 4-6" and then compacted with a roller.