Economic and Environmental Geology

Indexed in /covered by CAS, KoreaScience & DOI/Crossref:eISSN 2288-7962   pISSN 1225-7281

Table. 1.

Table. 1.

Description and interpretation of lithofacies in the Duwon Formation

Facies Code Lithofacies Occurence Description Interpretation
Gm Massive conglomerate FA-1, FA-2 Subrounded to rounded, clast-supported pebble to boulder; coarse to very coarse sand matrix; poorly to moderately sorted; a(t)b(i) imbricated fabric; slightly normal grading; crude stratification; concave-up or sharp, planar lower boundary; 0.2 to 1.6 m thick Bedload deposition as gravel sheets or longitudinal bars in channel
Gp/gSp Planar crossstratified conglomerate or gravelly sandstone FA-1, FA-2 Subrounded to rounded pebble to cobble supported by sandy matrix (Gp) or coarse to very coarse sand with pebble clasts(gSp); poorly to moderately sorted; planar cross-stratification; sharp and slightly erosional lower boundary; 0.2 to 1.3 m thick Migration and deposition of(sandy) gravel bars
Gt Trough-filling conglomerate FA-3 Angular to subangular pebble to boulder rip-up mudstone clasts (Mp) with subrounded to rounded pebble clasts; coarse to very coarse sand matrix; poorly sorted; concave-up or sharp, planar lower boundary; 0.3 to 0.8 m thick Crevasse channel-fill deposits
Sh Horizontally stratified sandstone FA-1, FA-2, FA-3 Alternating layers (<2 cm thick) of medium to very coarse sand with pebble clasts; sharp or slightly erosional lower boundary; 0.2 to 2.8 m thick Upper flow regime plane bed
Sr Ripple crosslaminated sandstone FA-1, FA-3 Very fine to medium sand; asymmetrical; gradual or sharp lower boundary; 0.1 to 0.2 m thick Migration of 2D ripples
Sm Massive sandstone FA-1, FA-3 Coarse to very coarse sand with scattered pebble clasts; poorly sorted; sharp lower boundary; 0.3 to 1 m thick Rapid deposition from decelerating sediment-laden flow
Mg Gray mudstone FA-1 Gray todark gray clay and silt; homogeneous; gradual lower boundary; 0.2 m thick; Deposition fromsuspension settling in standing water under poorly drained conditions
Mp Purple mudstone FA-3 Purple-colored clay and silt; homogeneous; burrows; calcrete nodules; sharp lower boundary; 0.05 to 1.5 m thick Depositionfrom suspension settling during overbank flooding under well drained conditions, post-depositional modification
Econ. Environ. Geol. 2021;54:441-56 https://doi.org/10.9719/EEG.2021.54.4.441
© 2021 Econ. Environ. Geol.