Flow Unit Model of Channel Sand Body and Its Effect on Remnant Oil Distribution: A Case Study of PI Formation in the Eastern Transition Zone of Daqing Oilfield

Table 1

Methods for calculating channel width.

Methods	Formula	Notes	PI1	PI3
Schumm [47]	; %	: channel width; : depth; : average thickness of channel sand body; 110%: compaction coefficient; : percentage of shale content; : river span.	54.75 m	60.23 m
CAS			54.88 m	60.37 m
Leopold [48]			52.88 m	59.86 m
Dissection of dense well pattern	Distance of two wells in the abandoned channel <  < two wells from the abandoned channel to the point bar	B2-5-BW101—B2-5-P100 <  < B2-60-B271—B2-60-FB271		m
Average	—	—	54.18 m	60.1 m