Land includes erosion and landforms {landforms}.
Rocks can move, break down, and wear away {gradational process} {erosion}|. Moving glaciers, flowing water, freezing, and thawing can cause erosion. Ocean waves cause erosion. Water movements and chemical reactions cause most erosion. Erosion is faster if water flows faster or contains more chemicals that react with minerals. Erosion also involves plants and plant roots. Sand blown by wind does little eroding.
shore
Ocean erodes centimeters from rocky shores {shore} each year. On deep and steep shores, ocean-wave erosion makes cliffs. On shallow gently sloping shores, ocean-wave erosion builds sandy beaches or sandbars.
Water can carve rock channels {fluvial landform}|.
Water can flow under surface {sapping} and cause ground erosion.
Large ice masses {glacier}| move 1 to 40 feet per day.
Glacier can have large deep crack {crevasse}|.
If glaciers reach sea, parts {iceberg}| can break off.
Ice-Age glaciers were one mile thick. When they receded and dried, wind blew fine dust {loess}| all over world.
Glacier front edge pushes up soil and rock ridge {moraine}|.
Glaciers can have vertical holes {moulin, hole}, caused by flowing water.
Slope, material, and size determine land types {terrain}| {land forms}.
slope
Varying slope makes plain, hill, or mountain.
material
Surface material can be soil, bedrock, sand, cobblestone, boulders, ice, or water.
types
Surface can be piedmont rolling plains, caused by running water, glacial erosion, or wind sand-dune formation. Surface can be hilly plains, caused by minor tectonic processes or tableland erosion. Surface can be plains, from running-water sediment deposits. Surface can be tableland, mesa, butte, canyon, or escarpment. Surface can be low mountains, from long erosion. Surface can be high mountains, formed recently.
layers
Limestone layers were shallow sea. Coal layers were swamp. Salt or gypsum indicates sea dried instead of receding.
ore layer {lode}|.
mineral-deposit area {prospect, land}|.
Rocks {talus, cliff} can be at cliff base.
vertical rock point {aiguille}.
mountain {alp}|.
plant-less eroded mesas or hills {badlands}|.
cliff top {bluff}|.
small mesa {butte}|.
crest or ridge {chine}.
pass or gap {col}.
A mountain chain {Cordilleran belt} goes from Atlas Mountains, to Alps, to Himalayas, to Pacific-Ocean volcanic islands, to north China, to east Siberia, to west North-America coast, and then to west South-America coast.
rocky promontory {crag}|.
hill top {crest, hill}|.
above-plain inclined rock strata {cuesta}.
watershed {divide}|.
hill {eminence}|.
mesa side {escarpment}|.
Two large watersheds have boundary {great divide}.
small hill {hillock}|.
knoll or mound {hummock}|.
small hill {knoll}|.
mountain {massif}|.
tableland tops {mesa}| {upland}.
river cliffs {palisade, cliff}|.
Rolling plains {piedmont}| form by running water, glacial erosion, or wind sand-dune formation.
high flatland {plateau, land}|.
sea or lake highland projection {promontory}|.
cliff {scarp}.
un-eroded mountain range {sierra}.
Plains cut by streams make mesa, butte, canyon, and escarpment {tableland}|.
Trees do not grow above a mountain line {timberline}| {timber line}.
Hilltops {tor} can have rocks or be bare rock.
deep crevice {abyss}|.
usually dry stream gully {arroyo}|.
mesa spaces {canyon}|.
gorge or crevice {chasm}|.
glaciated-valley heads {cirque}.
gulch or ravine {coulee}.
fissure {crevice}|.
valley {dale}|.
small valley {dell}|.
dry region {dust bowl}.
long narrow crack {fissure}|.
valley {glen}|.
river-caused deep narrow area {gorge}|.
stream channel {gully}|.
low and wet region {morass}|.
water-made deep narrow area {ravine}|.
muddy area {slough}|.
Glaciers can form small mountain lakes {tarn}.
Lower shore {tideland}| is under water at high tide.
low coastal land {tidewater}|.
valley {vale}|.
dried riverbed {wadi}.
plain {champaign}.
un-forested rolling plain {wold}.
Sand dunes {brachan} can be separated sand crescents.
Sand dunes {seif}| can be parallel to wind.
island group {archipelago}|.
Land {cape, land}| can project into sea.
Land {headland}| can extend into water.
Narrow land {isthmus}| can be between two oceans.
Large land {peninsula}| can project into sea.
Coral rings {reef}| {atoll} can form around volcanic islands.
Sandy areas {sandbar}| can be near shore.
sandbar {shoal}|.
shore {strand, shore}|.
tree-shaded area {arbor}|.
tree-shaded area {bower}|.
shrub and thicket area {chaparral}|.
treeless field {clearing}|.
forest open area {glade}|.
heather-covered land {heath, land}|.
Rolling plains {moor}| can have shrubs and no forests.
Desert planted areas {oasis}| have water.
Areas {verdure, area}| can have healthy green plants.
grapevine field {vineyard}.
rabbit land {warren}|.
South-America treeless grassy plain {pampas}|.
Grassy soil {sod, soil}| can have intertwined roots.
small grassy area {tuffet}| {tuft}.
small grassy area {tussock}|.
South Africa has flat grassy areas {veldt}|, where animals graze.
Firs and spruces {taiga} cover north Eurasia south of tundra.
woodland or hilly land {weald}.
Hedges or tree rows {windbreak} can be on windward side.
rock or snow slide {avalanche}|.
Regolith can move slowly {creep}.
Loose regolith can break away {landslide}| from valley wall.
Rivers and streams transport eroded, decomposed, and disintegrated rock {regolith}.
Soils {soil, land} have types and properties {pedology}|. Soil comes from eroded rocks and decayed organic matter. Soil {mountain soil} derived from lava is rich in minerals. Iron oxides cause red, yellow, or brown soil color. Humus causes black or dark-brown soil color. Soil can be acid or alkaline. Soil has layers.
Soil can have varying calcium, sodium, potassium, phosphorus, nitrogen, iron, magnesium, and sulfur amounts {soil fertility} {fertility, soil}|.
Clay and shell mixtures {marl}| can be fertilizers.
Soil types {soil texture} depend on soil particle size {peds}|. Gravel has largest peds and coarse texture. Sand is next largest. Silt is third largest. Clay has smallest peds and fine texture.
Soil can have no soil profile {azonal soil profile}.
Soil can have unstable but layered soil profile {intrazonal soil profile}.
Soil can have stable soil profile {zonal soil profile}.
Hardened soil layers {pan layer} can be below topsoil.
Soil surface layers {topsoil} can be porous and 0 to 24 inches thick.
Sediment from rivers makes sandy soil {alluvial soil}|.
humus and sand {chernozem}.
decayed organic matter {humus}|.
clay, silt, and sand mixture {loam}|.
Dry soils have different types {chernozemic soil} {grunosolic soil} {decentic soil}.
Humid soils have different types {podzolic soil} {latosolic soil} {tundra soil}.
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Date Modified: 2022.0225