Date of Award
Master of Science
Geological and Environmental Sciences
Dr. William B. Harrison III
Dr. W. Thomas Straw
Dr. Richard Passero
Masters Thesis-Open Access
Pennsylvanian outcrops along the Michigan Basin's southern/margin are composed of fluvial-deltaic and marine shelf sediments. Constructive deltaic facies include point-bar sandstones displaying erosional bases, channel lag, and upward decreasing grain size and sedimentary structures. Cross-stratification data indicate a unimodal, highly variant, northward-trending, paleocurrent pattern that deviates from regional paleoslope. Point-bar sandstones record delta plain deposition by meandering distributary channels. Channel margin facies include Lingula-bearing, interdistributary bay shales; overlain gradationally by laminated, flaser-bedded and rooted marsh shales and siltstones; and subbituminous swamp coal. Bay-fill facies are interrupted by lens-shaped, quartz-poor, fine-grained, crevasse-- splay sandstones.
Delta destructive facies--quartz -rich bioturbated sandstone-- suggest delta lobe abandonment and landward reworking of delta front sands over the subsiding deltaic plain. Subsidence resulted in deposition of thin, marine shales and overlying micrites which contain diverse marine fauna and <20% terrigenous clastic detritus.
Martin, Jeffrey R., "Pennsylvanian Deltaic Sedimentation in Grand Ledge, Michigan" (1982). Masters Theses. 1674.