Hailar Basin

located on the west side of Da Hinggan Ling

is a fault depression laid upon the folded basement of Hercynian movement with a area of 70480km

2

.Fluviatile and lacustrine deposits of the Jurassic Jalai Nut Group(J

3

zl)are up to 5300m thick with 7 sags in which their formation thicknesses are thicker than 3000m.The 1000-2000m thick Damoguaihe Formation of the Jalai Nut Group(J

3

d)is considered to be the maim source bed in which 400-600m thick source rocks are found.Their organic carbon is 2.148%

chloroform bitumen A 791ppm

and total hydrocarbon 379ppm.Based on hydrocarbon productivity

vitrinite reflectance and the n-alkane distribution

the oil generation threshold here is 1500m

and the peak is 3500m.Now commercial oil flow is obtained from sandstone reservoirs.5 kinds of traps

i.e. structural

stratigraphic

lithologic

buried-hill and volcanic traps could be found

and petroleum prospects is brilliant.