Abstract: Tuyuke oilfield consists of deep heavy oil reservoirs with characteristics of high crude density, high viscosity, high bitumen content and low light component, closely related to the reservoir-formed conditions and processes. Based on the analysis of the source rock, reservoir, cap rock, hydrocarbon migration and structural evolution history, it is considered that crude in Tuyuke oilfield is mainly generated from Permian source rock, hydrocarbon generation and expulsion is in Late Triassic-Early Jurassic ; Karamay formation in Middle Triassic is as i ts reservoir ;mudstone with the thickness of 50~170 m in top of Karamay formation is as caprock ;faulted anticline-faulted nose structure formed in Karamay movement of the end of Late Triassic, was reformed and developed by Indo-China movement and early-middle Yanshan movement ;hydrocarbon migration occurred in Late Triassic-Early Jurassic and Late Cretaceous dominated by the former ;and hydrocarbon migration channel is faults in Lukeqin structural belt and high permeabili ty sand layer in Karamay formation.

Key words: Turpan basin, Hami basin, Viscous oil reservoir, Structure, Trap, Preservation, Hydrocarbon generation, Hydrocarbon migration