Keywords: 
• the deep bed of Dongying depression /
• faults controlling sand /
• valley-troughs controlling fan /
• formation patterns of sand bodies

Abstract: Faults and ancient valley-troughs controlled the development of deep sand bodies in Dongying depression by analyzing borehole data, seismic data and previous conclusion. The fault is key element to control the distribution of sand bodies in the northern part of Dongying depression. The sandstone distributes along downthrown side of main faults like skirt sides. The intensity of the faults activity decided the thickness of sandstone, the changing trend line of the fault throw is consistent with the thickness of sandbodies. The intensity of the faults activity also controlled the facies type of sandbodies. The deep faults activity gradually intensified from north to south in Dongying depression due to the northern-faulted and southern-overlapped structural setting, so the facies type of sandbodies are changed from nearshore subaqueous fans in the northern part to braided river deltas in the middle part and to fan deltas in the southern part. The ancient valley-troughs which include the fault troughs and the incised valley with extensive development obviously controlled the distribution of sandbodies in the southern part of Dongying depression as a result of the lack of the deep-large faults. The developing succession of the ancient valley-troughs resulted in the vertical superposition of sand bodies from Sha 4 member to Sha 3 member. At last, the formation patterns of deep sandbodies in Dongying depression were set up according to controlling factors.