Geomorph/Surficial Processes/Quaternary Geology Flashcards
Karst
topography underlain by limestone, dolomite, gypsum, or other rocks that can be effected by dissolution. Characterized by surface depressions.
Conditions Necessary to Develop Karst Terrain
- Soluble Rock, preferrably limestone, at or near surface
- Dense Rock, highly jointed, thinly bedded
- Entrenched valleys below uplands underlain by soluble, well jointed rocks
- region of moderate to abundant rainfall
Depositional Karst Features
Dripstone: travetine deposits from calcium carb rich water dripping from ceiling of cave
Helictite: twig like deposit forms in cavern with not enough water to form drips
Travertine: deposit of calcium carb precip found in limestone caverns coating walls, floors, and ceilings
Erosional Karst Features
Blind Valley, Cavern, Hum, Karst Window, Lapies,
Natural tunnels and bridges, Polje, Sink, Sinkhole
Ponds or lakes, Sinking creeks, Solution Valley,
Subsidence Trough, Terra Rossa, Uvala
Glacial Feature Categories
Continental Glaciation: covered much of central and northern US during last Ice Age
Alpine Glaciation: Found in many mountanous regions
Esker
Serpentine shaped stratified deposits, developed as load carried by streams flowing beneath, within, and above glacier, once they become stagnant, the deposits are dropped. Appear like inverted stream channel.
Drumlin
Elongated, ellipsoidal feature composed of material ranging from till to large rock fragments, some could have bedrock core. Streamlined hills are clustered and found near terminal and recession moraines.
Drift
rock and associated material carried and deposited by glacier, includes terms grouped under till.
Kame & Kame Terrace
small hummock or terrace of ice-contact drift resulting from deposition of sediment either in crevasses at surface of glacier, often from streams flowing at edge of glacier along contact of ice with valley wall. contain poorly sorted stratified sands and gravels.