-is the wearing away of a material by objects rubbing against each other.
-is also known as either top soil or the zone of leaching. Typically it is dark colored because of
the humus (organic materials). Decomposed materials are washed out of this layer, a process
known as leaching.
-soil layers-Opal's Pals
-is an unweathered grain, often with an irregular shape and sharp edges.
-angular sand grain-quartz
-angular grains-Opal's Pals
-semi-angular quartz sand grains
-is the ore of aluminum, hydrated alumina.
Bauxite often has a pisolitic structure (made of small
--is the second layer of soil. It is also known as the zone of accumulation because materials
washed down from the top layer, clay and iron oxides, accumulate in this layer.
-soil layers-Opal's Pals
-is a particle size larger than a cobble;
there is no upper limit established as to how large a
boulder can be.
-is a soil cemented by lime (calcite);
caliche is very common in the Southwest. Caliche closely
-caliche: 1 2
-consists carbonated water; carbonic acid is
a weak acid made of carbon dioxide and water.
Carbonic acid can eventually cause the decomposition of most silicate minerals.
-occurs when a mineral is changed into a
different mineral through the process of a chemical
reaction; the new mineral is usually less resistant to further weathering.
Chemical Weathering of Igneous Minerals-Lecture NEW
-pyrite weathering to sulfur and iron oxides-A
-pyrite weathering to sulfur and iron oxides-B
-pyrite weathering to sulfur and iron oxides-C
-chemical weathering lecture
chemical weathering of feldspar
-Chemical weathering of feldspar changes feldspar into clay
-weathered feldspar within an igneous rock (2 views)
-is the third layer of soil that consists of
-soil layers-Opal's Pals
-can either refer to the tiniest particle
size (submicroscopic particles) or it can apply to a class of
silicate minerals that only produce crystals in the submicroscopic range (clay minerals).
-is the particle size between a pebble and a boulder. A cobble is often described as "brick-sized".
devitrification of obsidian
-Like all glasses in which the constituent
atoms are arranged at random, obsidian breaks down as
it slowly crystallizes over thousands or even millions of years.
-pitchstone is obsidian undergoing devitrification.
*due to differences in hardness, toughness,
types of cementation, and chemical composition, some
rock types break down (weather) faster than other materials.
-differential weathering between chert and limestone
-is the process of dissolving a material; the material goes into solution.
-is the process of carrying away materials
in contrast to weathering which causes the breakdown
-is a weathering process, common in semiarid
regions, in which the weathered outer portion of a
granite boulder peels off in slabs parallel to the surface of the boulder. This weathering process is
often compared to the layers of an onion.
-is the property of a rock, such as shale, of splitting into thin layers.
-Frost wedging of folded siltstone, Santa Catalina Mountains, Arizona
-is the measure of how easy it is to crumble
-Water gets into a crack, freezes, and
expands; the tremendous pressures exerted by the expansion
of water into ice can cause the rock to split further.
-Frost wedging of thin-bedded siltstone
-Soda cans split by ice expansion
-is a pile of small fragments from a
decomposed granite. This loose material contains single grains
of quartz, mica, and weathered feldspar as well as small clumps of these minerals.
-is a cemented soil, such as caliche.
-is a reddish brown to dark, sub-metallic mineral consisting of iron oxide
-basalt weathering to hematite, Maui, Hawaii
-consists of dark organic matter found in soil.
-is a chemical reaction in which water is
added to the chemical formula of a mineral: the addition
of water to the mineral anhydrite changes its chemical composition and the material becomes
-occurs when hot mineralized water coming
from an igneous intrusion changes the composition
and structure of the minerals in the surrounding country rock.
-hydrothermal alteration, close up
alteration of volcanic ash
-hydrothermal alteration and spheroidal weathering of basalt in Maui: 1 2 3
-is a steep-sided hill which is a residual
remnant in the erosional process that leveled most of the
-is a common clay mineral. Kaolinite is the
kao in Kaopectate; if you consume clay, it will have
an effect on your digestive process.
-is a chemical process in which water moving
through permeable rock materials dissolves some
minerals and then carries these minerals to another area.
-minerals bleached by leaching process
-Water getting into a joint leaches out some
minerals and deposits others in a curved
-is a hydrated , yellow-brown iron oxide.
-basalt weathering to limonite, Maui, Hawaii
-is the form of weathering whereby a larger
rock is broken into smaller fragments without a
change in chemistry.
-California coast-wave action
-decomposing shale-frost action
-occurs when a mineral picks up extra oxygen in its structure a changes to a new mineral.
As an example, magnetite in basalt is altered to a red hematite.
-red soil in Maui, Hawaii
-old cars rusting in Nevada desert
-is a soil formed in warm humid regions, rich in iron oxides (red) and clay (gooey).
-is a soil found in semiarid regions, rich in calcite.
-is the breakdown of rocks into smaller
pieces without any change in chemistry; also called
-is the loose material on top of bedrock: soil, gravel, boulders, etc.
-consists of rock that has been crushed and ground to a fine powder by glacial action.
-Roots grow to a thin crack in a rock; as the root grows it exerts pressure and expands the crack.
-is a weathered grain, where the sharp edges of the grain have been worn off by erosion.
-sand from Bermuda-rounded shell fragments
-sand from Hawaii-partially rounded volcanic fragments
-semi-rounded basalt sand grains
-is the physical weathering process of
converting angular grains to a rounded shape, primarily by
-rounded beach pebbles-Maui, Hawaii
-rounded beach pebbles
salinization of soils
-is the buildup of salt in the soil thereby
decreasing the useful of the soil for agriculture; a growing
problem in the western part of the United States.
-If there is insufficient drainage of
agricultural watering of crops, salt (which is produced by the
breakdown of soil minerals) is not washed out of the system. Consequently, the concentration of
salt slowly builds up until plants cannot live in the soil.
-is a physical weathering process similar to
frost wedging but instead is caused by the growth of
salt crystals within cracks. The force of the growing salt crystal is sufficient to widen cracks in rocks.
-is a grain size between granules and silt.
-beach sand, Kihei, Maui, Hawaii
-black sand, Hana, Maui, Hawaii
-magnified sand grains-black volcanic sand
-magnified sand grains-immature sand
-magnified sand grains-rounded shell fragments
-magnetite sand- 10x 30x
-fine grain quartz beach sand- 10x 30x 30xb
-basalt beach sand from Hawaii, big island- 10x 30x
-consists of decomposed, crumbly granite; basically it is a "dead" rock.
-is the same as sap rock: "sapro" means
-refers to sets of joints in bedrock that
are produced by unloading; the joints produced by this
process are usually parallel to the surface of the Earth.
-is a particle size larger than clay
particles but smaller than sand grains. This material feels gritty
but you cannot see the individual particles with the naked eye.
-is finely broken down rock material on the
-soil layers, Kebler Pass, Colorado
-Idaho-Craters of the Moon-dirt
layer of new soil
-soil from Maui, Hawaii
-occurs when loosely compacted material settle, often after rain storms.
-tension fractures resulting fro soil compaction
-consists of a chemical dissolved in water.
-Chemical weathering within fractures in
rock first causes a breakdown of the corners of the block
and then edges of the block are also destroyed, thus producing a rounded boulder from an angular
-spheroidal weathering: 1 2 3
-consists of loose rock that has slid down a slope.
-is an inclined surface made of talus.
-Mt. Whitney-talus slope
-Mono Craters-talus slope
-is where limestone in a semiarid environment weathers into a very sharp, raspy surface.
-occurs when most materials are heated.
Similarly, most materials contract in size when cooled.
Repeated heat-cold cycles loosen grains within rocks and may cause the rock to eventually
-refers to the frequencies of light just
outside of the normal visible spectrum, just past violet.
This type of light is responsible for sunburn on bright, sunny days. Ultraviolet light can cause
chemical changes in minerals; many colored minerals such as amethyst, rose quartz, and pink
topaz can fade when exposed to ultraviolet light.
-minerals that fluoresce under ultraviolet light
-occurs when the pressure is reduced of a
rock that formed under pressure, the rock expands and
breaks. Granite intrusions formed at depth crack and split when the overlying bedrock is removed
-jointing in an granite intrusion
-is a thin layer of silt or clay deposited on the bottom of a lake bed on an annual basis.
Sediment varies slightly from winter to summer, producing small distinguishable layers.
-is mechanical weathering force capable of
breaking and rounding rock fragments through
-California coast-wave action
-is the breakdown of rocks and minerals by chemical and physical processes..
-is the outer part of a rock when exposed to
weathering process often changes color; this is why a
rock must be broken in order to see a fresh surface.
-weathered basalt, Maui, Hawaii