Abstract: The emphasis and difficulty is the development of carboniferous igneous rocks oil and gas in the belly of Junggar Basin in recent years. The porosity of fifty-four wells carboniferous igneous rocks in Shixi Oilfiled is being studied. The result has been shown that the higher porosity of conglomerate rocks and carbonate rocks than in similar depth and igneous rocks in shallow depth. The research has indicated that lithology and burial diagenesis determine the development of the porosity of deep-seated igneous rocks in carboniferous in Shixi Oilfield. And burial diagenesis is the key factor.

Key words: Shixi, deep-seated, igneous rocks, high porosity, carboniferous