Lop-nor has long been misunderstood as a "wandering lake". Its location

size

shape as shown on old maps and in past literatures are not correct. Began from the sixties

the aero-photos

and seventies

the Landsat images were obtained. They showed accurately all the detailed natural criteria of the Lop-nor: it had been a very stable

in-land lake

and was controlled by geo-tectonic and neo-tectonic in shape and evolutions. The water pouring into the lake from the rivers enormously deduced

and finally the lop-nor dried out totally at the beginning of seventies.The centeral part of the lake is located in the successive subsidence area of "Aqik Gra-ben". The author considers that this study has used all the recent remote sensing images with high precision so there should be no further rumor that the Lop-nor had been a wandering lake.Lop-nor was fed by two water systems

one of it was the river water that entered the NW part of Lop-nor-namely Kon-quie Dyria

the other was the river water both from Tarim and Cher-cheng

the discharge from the former was only a small proportion. The biggest surface area of the lake in the history had been about 12600 km

the lake in laterstage had a longer period of water storage

the water surface area was about 5140 km2. Before the Tarim river flew into the lake

it formed 5 overlapping

advancing alluvial fans

which meant 5 stages of sinking of Lop-nor.The occurence of "horst" in the W and NW part of Lop-nor is the conclusion of the author’s image interpretation. On the image

one cannot find a normal western lake margin. There had been small amount of water immersions on the most northern part of the horst that fed by the Konquie Dyria

but there was no trace of lake water that had immersed the whole horst. At the west wall （steep-bank） of the Fa

the Tarim River water flew along the bank towards N

but could not enter the lake.