Recherche pétrolière et gazière

Abstrait

Synchrotron Powered Transmission X-ray Micro-tomography System in Shale Gas Micro-structural Characterisation

Marek S Zbik, Trzciński JT, Williams DJ, Song YF, Wang ChC and Frost RL Ray

The shale gas renaissance was brought about by improved methods of well drilling and completion by hydraulic cracking technology. It has become increasingly urgent to developed new method of 3-D characterisation of potential rocks collectors. Release of gas from compacted shales needs new aproach to void promoting and increasing technology and new monitoring characterisation. In present study the transmission x-ray microscope (TXM) method was validated in microstructural study of mudstone shale sample. High structural complexity was observed. Initial structure displays anisotropic aggregate network with highly elongated voids 0.2 to 1.5 μm in diameter and the bulk porosity about 12-20% and pore average diameter vary between 125 to 283 nm. Texture of this rock is laminar and two distinctive lamellas direction was observed with angle between them about 20º. The average distances measured between mine stream lamellas was around 400 nm which is twice than average voids dimension. It was noticed that ultrasonic action on the shale rock has significant influence altering it microstructure. Voids becoming larger after ultrasonic treatment with porosity system increased in value above 30%, pushing up the rock permeability.