Inter-salt mud shale layer-series lithofacies classification method and verification method

Abstract

The invention provides an inter-salt mud shale layer-series lithofacies classification method and verification method, belonging to the field of shale oil exploration geology. The inter-salt mud shalelayer-series lithofacies classification method comprises the following steps: determining the stratification thickness of mud shale by observing the core of the mud shale and authenticating with an optical microscope; determining the core through the whole-rock mineral analysis so as to confirm the rock mineral type of the mud shale; determining the abundance of the organic matter of the mud shale through pyrolysis organic carbon analysis; determining the rock mineral volume content, corresponding to the rock mineral type, of the mud shale through whole rock mineral analysis in combination with the observation of a slice under the microscope; and classifying the rock type of the mud shale by adopting a 'four-component three-end member' principle classification method based on the rock type according to the volume content of detrital mineral components, calcite components and dolomite component in the mud shale. The inter-salt mud shale layer-series lithofacies classification verification method verifies by using a natural gamma ray spectrometry and conventional logging curve characteristics that the rock of the mud shale classified into the same lithofacies has the same rock-electricity characteristics.

Description

technical field [0001] The invention relates to the field of shale oil exploration geology, and in particular to a lithofacies division method and verification method of inter-salt mud shale formations. Background technique [0002] The exploration and development of shale oil and gas in unconventional oil and gas resources has achieved great success in the United States, and has become a hot research direction and exploration field in the world. When observing the shale formations, it is found that its color, composition, structure, structure, reservoir space characteristics and oil-bearing properties all show strong heterogeneity, which is mainly attributed to its complex mineral composition, rapid change of lithofacies types, and grain formation. characteristics of layer development. Scholars at home and abroad have carried out a lot of research on the types of shale reservoir space and achieved fruitful results, but there are relatively few studies on the classification...

AI Technical Summary

Problems solved by technology

Using fine core description and a large number of thin sections, cathodoluminescence, X-ray diffraction energy spectrum analysis, chemical analysis, etc., combined with scanning electron microscope, electron probe and whole-rock X-ray diffraction, it is observed under the microscope that the mud shale laminae in the inter-salt formation are extremely developed; Except for salt minerals, which are easy to identify, terrigenous clasts and carbonate minerals are of micrite grade, which are difficult to identify; salt minerals (mainly glauberite) have various forms and complex origins

Images