Sandbodies of Guantao Fm in Zhuang 106 wellblock in Laohekou oilfield are mainly of channel

bank

flood plain and abandoned channel subfacies. The channel sandbodies in the upper Guantao Fm deposited in meandering river environment are the main oil-bearing formations. Migration and accumulation of the Neocene hydrocarbons in the study area

surrounded by sags with rich source rocks

were controlled by faults. The large and small faults were connected into a network. Hydrocarbons alternatively migrated along the fault planes in vertical direction and along the reservoirs in lateral direction

forming a network-blanket migration and accumulation pattern. The rich source rocks

favorable migration and accumulation conditions

as well as good reservoir-cap rock combinations have led to the formation of subtle oil and gas reservoirs dominated by lithologic and lithologic-structural reservoirs. From south to north

the number of oil-bearing layers gradually increases

their depths enlarge and the oil-bearing properties get better.