Carbonate reservoirs in the Tahe oilfield feature in fractures and vuggies.Nuclear magnetic resonance(NMR) was therefore employed to analyze these formations.The paper expounds on the working principles of NMR imaging as well as T

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spectrum in rock property testing.By using these technologies

the authors established the spatial structures for cores and classified the carbonate reservoir space types.They also carried out oil and water detection

and studied conditions for fluid moving inside the cores and methods for appraisal of reservoir development effect.The results show that NMR can directly detect fluid and its distribution inside the cores

and that no connection exists between testing results and the shape and size of the samples.The carbonate reservoirs in the Tahe oilfield can be classified into four main types:pore(matrix)

dissolution pore

fracture

and pore-vug-fracture

each has unique NMR imaging and T

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spectrum characteristics and therefore can be easily recognized.The T

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cutoff value(an important physical parameter for evaluating the development potential of carbonate reservoirs) of the carbonate reservoirs in the Tahe oilfield is 86.25 ms.Application of the methods in different blocks with carbonate reservoirs in the Tahe oilfield indicates that the prediction of reservoir development accord with the actual results

thus verifies the feasibility of the method in the evaluation of carbonate reservoir development.