Effect of pyrolysis on elastic properties and microstructure of organic-rich Mancos shale

We have studied changes of static and dynamic elastic properties of the organic-rich Mancos shale caused by heating to the temperature within the range 380°C-550°C. An increase of ultrasonic velocities and static Young's moduli has been observed in the samples that experienced temperatures up t...

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Bibliographic Details
Main Authors: Pervukhina, M., Uvarova, Y., Dautriat, J., Dewhurst, D., Patrusheva, N., Lebedev, Maxim
Other Authors: SEG
Format: Conference Paper
Published: SEG 2014
Online Access:http://hdl.handle.net/20.500.11937/38658
Description
Summary:We have studied changes of static and dynamic elastic properties of the organic-rich Mancos shale caused by heating to the temperature within the range 380°C-550°C. An increase of ultrasonic velocities and static Young's moduli has been observed in the samples that experienced temperatures up to ~400°C. Further heating to temperatures up to 550°C has led to the decrease of elastic moduli. The samples subjected to temperatures above 430°C show an increase in stress sensitivity, which implies microcrack generation. Micro-CT images of small samples have been obtained to inspect the microstructural changes caused by this dry pyrolysis. Comparison of the registered micro-CT images of Mancos shale samples subjected to temperatures up to 470°C shows significant shrinkage of the kerogen that fills pore spaces resulted from bitumen expulsion into the pores.