Chemical diagenetic constraints on the timing of cataclasis in deformed sandstone along the Pine Mountain overthrust, eastern Kentucky

The small quantities of early-formed, intergranular cement within the cataclasites (average 3.7 volume percent), show evidence of breakage and accordingly, must have largely pre-dated the deformation. Quartz cementation modeling (Touchstone™) suggests that emplacement of this pre-deformational intergranular cement within these deformed rocks can be bracketed within a period from approximately 280 to 260 Ma. An interpretation of fault movement that shortly post-dates this initial period of quartz cementation is consistent with other estimates for the timing of the Alleghanian orogeny. Because of their protracted period of burial, rocks in the vicinity of the PMO remained at temperatures amenable to continued quartz cementation until the middle Cenozoic, and thus, most of the quartz cementation in the cataclasites and also in the surrounding undeformed sandstones post-dates movement on the fault.