Delta front thin oil reservoir recognition method

Abstract

The invention relates to a thin oil reservoir recognition method, in particular to a delta front thin oil reservoir recognition method. The delta front thin oil reservoir recognition method comprises the following steps: 1) correcting a shoulder bed effect; 2) determining that delta front thin oil reservoir sedimentation types include three kinds of sedimentary microfacies of an underwater distributary channel, an estuary dam and sheet sand; 3) establishing a thin sand body connectivity analysis method under guidance of a sedimentary microfacies mode; 4) determining an oil reservoir recognition standard; 5) achieving classification and three-dimensional recognition from a single-well thin oil layer to a multi-well thin oil reservoir in combination with fluid electrical property limit and a reservoir forming control factor based on the thin oil reservoir space distribution characteristic. The delta front thin oil reservoir recognition method disclosed by the invention achieves classification and three-dimensional recognition from the single-well thin oil layer to the multi-well thin oil reservoir and effectively improves recognition accuracy.

Description

technical field [0001] The invention relates to a method for identifying thin oil reservoirs. Background technique [0002] Thin reservoirs usually refer to reservoirs with effective vertical thickness of sandstone less than 1.0m. For sandstone thicker than 2.0m, the transmitter coil of the logging tool transmits signals to the receiver coil, and the transmission path is all sandstone. For thin sandstone with a thickness of less than 1.0m, the proportion of sandstone in the transmission path of logging information is less than 60%, the degree of influence of surrounding rock is large, and the signal-to-noise ratio of data is low (attached figure 2 ). The vertical resolution of the deep induction resistivity curve is about 1.6m, and further correction is needed to invert the "true value" of the logging response of thin sandstone to reduce the influence of surrounding rocks. The existing technology uses the conventional resolution matching method to correct the deep inducti...

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Problems solved by technology

However, from the point of view of the specific implementation process, this method also has shortcomings. First, it is difficult to determine the accurate instrument response function, and second, the shape of the two input logging curves is similar, which leads to limitations in application.

[0003] A large amount of thin sandstone is deposited in delta front subfacies, and thin sandstone can be formed in sedimentary microfacies such as underwater distributary channel, distributary bay, mouth bar, far sand bar, and sheet sand. Changes quickly, making it difficult to track

First, the pore structure, spatial geometry and logging response characteristics of different sedimentary microfacies thin sandstones are significantly different, resulting in inconsistent fluid electrical boundaries. Insufficient information utilization rate of hidden control factors, application has certain limitations

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