Method and device for predicting porosity of deep sandstone reservoir

Abstract

The invention provides a method and device for predicting the porosity of a deep sandstone reservoir, and the method comprises the steps: determining a time-temperature index TTI of each position point of a well logging according to the formation temperature data of each position point of the well logging; establishing a sandstone reservoir porosity prediction model according to the sandstone reservoir porosity, the sandstone reservoir granularity, the quartz content and the TTI of each position point of well logging; obtaining formation hierarchical data and ground temperature gradient of the target interval; determining the TTI of each position point in the target interval according to the formation hierarchical data and the ground temperature gradient of the target interval; and determining the sandstone reservoir porosity of each position point in the target interval according to the TTI of each position point in the target interval and the sandstone reservoir porosity prediction model. According to the method, by introducing the TTI, the geological effect brought by the geothermal field can be accurately characterized, so that the prediction accuracy of the porosity of the deep sandstone reservoir is improved, subsequent development is better guided, and the exploration success rate is improved.

Description

technical field [0001] The invention relates to the technical field of reservoir evaluation in petroleum and natural gas geological exploration, in particular to a method and device for predicting the porosity of deep sandstone reservoirs. Background technique [0002] Porosity is a key parameter for oil and gas reservoir evaluation, and the size and evolution of reservoir porosity are closely related to diagenesis. At present, the prediction methods of reservoir porosity at home and abroad can be roughly divided into five categories: porosity prediction methods based on depth index; porosity prediction methods based on diagenetic physical experiments; porosity simulation methods based on reservoir pore evolution history; Reservoir Porosity Prediction Method Based on Seismic Facies; Porosity Prediction Method Based on Local Decision Tree Algorithm. However, in areas where burial thermal effect diagenesis is dominant, for sandstones with a certain compositional maturity and ...

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Problems solved by technology

However, in areas where burial thermal effect diagenesis is dominant, for sandstones with a certain compositional maturity and structural maturity, the geothermal field is an important factor affecting the porosity of the reservoir, and the deeper the formation, the greater the influence of the geothermal field. For deep sandstone reservoirs The above method cannot accurately take into account the influence of the geothermal field on the porosity of the reservoir. Therefore, in the area where burial thermal effect diagenesis is dominant, the prediction accuracy of the porosity of the deep sandstone reservoir predicted by the existing technology is low. Even deep sandstone reservoir porosity cannot be predicted

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