Laboratory Measurement and Interpretation of the Changes of Physical Properties after Heat Treatment in Tight Porous Media

Table 3

Heats of reaction for several minerals [34, 35].

Minerals	Temperature range, °C	Reaction after heat treatment
Illite and clay mica	125~250	Loss of hydroscopic water
Mg-chlorite	650	14 Å spacing is intensified
Fe-chlorite	500	14 Å spacing less intense, becoming broad and diffuse
Mixed-layer clays	<600	Varies with amounts and types of minerals present
Kaolinite, well crystallized	575~625	Replacement by amorphous metakaolin
Quartz	573	α → β inversion
Ca-carbonate	700–830	Decomposition