Rotation and Dewatering during Slaty Cleavage Formation: Some New Evidence and Interpretations

摘要: Microstructures in the Martinsburg Formation east-central Pennsylvania provide strong evidence supporting Maxwell's hypothesis (1962) that slaty cleavage formed during deformation of unconsolidated sediments by rotation phyllosilicate grains a loosely compacted sedimentary succession held open abnormally high pore-fluid pressures. The structures fall into two classes: those which indicate condition strata at time development, and pressures were prior to dewatering. The absence dewatering phenomena across where parallels bedding provides clue process development. Because intrusions other occur only particles are some angle bedding, inference is occurred when clays rotated away from parallelism with strata, providing avenues escape for pore water. It concluded, therefore, alignment phyllosilicates caused rather than converse, as commonly thought.