Open AccessChannels Ran Through It—The Lawrence Formation at Lone Star Lake, Douglas County, Kansas
Author(s) -
Paul Enos,
Robert D Jefferson,
Staci Lynn Goetz
Publication year - 2008
Publication title -
current research in earth sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.125
H-Index - 10
ISSN - 2157-9970
DOI - 10.17161/cres.v0i254.11786
Subject(s) - geology , siltstone , sedimentary depositional environment , bedding , deposition (geology) , geomorphology , sediment , channel (broadcasting) , geochemistry , facies , biology , engineering , structural basin , horticulture , electrical engineering
The upper part of the Ireland Sandstone Member of the Lawrence Formation exposed in the spillway of Lone Star Lake, southwest of Lawrence, Kansas, consists of abundant pinstripe-bedded shales and siltstones; thin, lenticular sandstone and siltstone beds; and meter-scale, channel-form sandstone and mudstone lenses. Soft-sediment-deformation structures, including load casts, ball-and-pillow, and pseudonodules are abundant. The lenticular and pinstripe bedding with bipolar paleocurrents suggests tide-influenced deposition. The crosscutting, channel-form deposits are interpreted as tidal channels in an environment with low energy but rapid sedimentation. The depositional environment was a tide-dominated, muddy upper estuary cut by tidal channels. Gravitational instabilities resulting from rapid deposition of sand over saturated mud produced inverse-density gradients that resulted in soft-sediment deformation.