Lower Paleozoic marine carbonate rock with a great thickness is universally distributed in the Tazhong region of the Tarim basin. Carbonate rock is always an important oil and gas exploration target in this region. Well TZ4S was successful in prospecting Upper Ordovician carbonate rock reservoirs and has discovered high-yield hydrocarbon flows. This study revealed that oil-bearing strata in this region are an excellent reservoir. This is a special new kind of reservoir formed by the transformation of infilling fluorite veins. It is different from the Lower Paleozoic carbonate reservoirs found in the Tazhong region. Analysis of the genesis of fluorite in consideration of various geological evidences indicates that the reservoir resulted from the transforming effect of Permian magmatism-related deep fluids on carbonate rock reservoirs. The latter were transformed by the former through dissolution, metasomatism and infilling, so that carbonate rock reservoirs and oil-gas pools related to deep fluid transformation were form. The classification of such a new type of reservoirs and oil-gas pools is of important and practical significance to oil and gas exploration in Lower Paleozoic carbonate strata in the Tazhong region, especially in vast areas influenced by Permian magmatism, and in the west segment of the No. 1 fault zone in this region.