Turpan-Hami Basin contains two types of source rocks and four petroleum systems suchas coal measure-noncoal formation combined type

noncoal formation type and Toksun

Taibei

Hami

Nanhu petroleum systems. Within the first type

oil traps that were mainlyformed in Late Cretaceous matched well with the peak period of hydrocarbon generation ofPermian-Triassic source rocks

thus forming Toksun petroleum system; the oil traps ofTaibei system were formed in Middle-Late Jurassic and matched well with the peak period ofhydrocarbon generatioll of Early-Middle Jurassic coal measures and that of Permian-Triassicsource rocks

thus forming Taibei petroleum system; Hami oil traps were formed in LateJurassic

matched with the peak period of Triassic lacustrine mudstone hydrocarbon generation

and formed Hami petroleum system.As for the noncoal formation system

since itscaprocks were formed so late and underwent three serious damages

large amounts of oil andgas were lost

it is not favourable to form large oil and gas pools.