Premium
The microscopic origin of thermal cracking in rocks: An investigation by simultaneous time‐of‐flight neutron diffraction and acoustic emission monitoring
Author(s) -
Meredith Philip G.,
Knight Kevin S.,
Boon Stephen A.,
Wood Ian G.
Publication year - 2001
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2000gl012470
Subject(s) - cracking , acoustic emission , neutron diffraction , thermal , diffraction , quartz , materials science , characterization (materials science) , ultimate tensile strength , neutron , neutron temperature , mineralogy , composite material , geology , optics , nuclear physics , physics , thermodynamics , nanotechnology
We demonstrate that neutron diffraction measurements make it possible to quantity elastic strains within the interior of solid samples, and thus have great potential for addressing a wide range of problems connected with the characterization of the mechanical properties of geological materials. We use the time‐of‐flight neutron diffraction technique, in combination with acoustic emission monitoring, to study the evolution of thermal strain within the interior of samples of a pure quartzite during slow heating, and the onset of the associated thermal cracking. Thermal cracking commences around 180°C when the thermal strain deficit along the a ‐axes of quartz grains induces a thermal stress that is close to the bulk tensile strength of the rock.