Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
22 Cards in this Set
- Front
- Back
|
Weathering
|
processesthat change the physical and chemical character of rock at or near surface
|
|
|
Erosion |
pickingup or physical removal of rock particles by an agent such as running water orglaciers
|
|
|
transportation |
movementof eroded particles by various agents
|
|
|
Mechanical Weathering |
physicaldisintegration/change |
|
|
chemical weathering |
decompositionof rocks and material from exposure to water and gases
|
|
|
Spheroidal Weathering |
therounding of rocks due to weathering |
|
|
differential weathering
|
tendencyof different rock types to weather at different rates
|
|
|
Pressure Release
|
mechanical type of weathering where a large mass of rockthat had originally formed under great pressure and at depth is graduallyexposed via uplift and erosion of overlying rock
|
|
|
As the giant rocks undergoing pressure release are exposed, __________ _________ form, parallel to the outer surface of the rock. |
Sheet Joints |
|
|
Themechanical effect of freezing water on rocks |
Frost Action |
|
|
frost wedging |
theexpansion of freezing water that pries rock apart. Partial thaw during day addsnew water to ice in crack of rock. Freezes at night adding to ice that isalready there |
|
|
actionof ice lifting soil or rock
|
frost heaving
|
|
|
Oxygen's role in chemical weathering
|
often combines with minerals orwith elements within minerals that are exposed at Earth’s surface.-iron in ferromagnesian minerals isseparated from the silica in the structure and then oxidized-formation of hematite in absence of water and limonite in the presence of it.
|
|
|
The role of Acid in chemical weathering
|
most effective agent in chemical weathering -strongcompound that gives off hydrogen (+) ions when they break down in water -hydrogenions disrupt atomic arrangement of most minerals -the mostimportant natural source of acid for rock weathering is dissolved carbondioxide in water= Carbonic acid
|
|
|
Soil |
loose unconsolidated material that covers most of Earth’ssurface -geologistscall this material regolith -soil isthe term they have reserved for a layer of weathered, unconsolidated materialcontaining organic matter and is capable ofsupporting plant growth.-45% rock and mineral, 5% organicmatter (humus), 50% pore space
|
|
|
soilcontaining equal parts sand, silt and clay
|
loam |
|
|
soil horizons
|
assoils mature, distinct layers appear
|
|
|
O-Horizon |
uppermostlayer that consists entirely of organic material
|
|
|
A-Horizon |
dark-colored soil layer that isrich in organic matter and high in biological activity. Formed when theO-horizon mixes with weathered mineral matter just below it.
|
|
|
E-Horizon
|
Organic acids and carbon dioxidefrom decaying plants percolates down to form the E-horizon aka the zone of leaching.
|
|
|
B-Horizon
|
material that leaches down fromthe E-horizon eventually forms the B-horizonaka zone of accumulation. Veryclayey and stained red/brown. This zone is often called the subsoil.
|
|
|
C-Horizon |
incompletely weathered parentmaterial beneath the b-horizon. Transitional between unweathered rock orsediment below and the developing soil above.
|
