Soil and Mechanical Weathering Essay

Submitted By Rub-Usim
Words: 763
Pages: 4
Open Document
Essen4als*of*Geology,
Weathering*and*Soils
Chapter*6
Stanley(Ha*ield
Southwestern(Illinois(College
Jennifer(Cole
Northeastern(University
(
Modified(by(G.(Smith

Earth’s External Processes
• !Weathering!–!the!physical!breakdown!and chemical!altera6on!of!rock!at!or!near!Earth’s surface
• Mass!was6ng!–!the!transfer!of!rock!and!soil downslope!under!the!influence!of!gravity "

Earth’s External Processes
• Erosion'–'the'physical'removal'of'material'by'mobile agents'such'as'water,'wind,'ice,'or'gravity '''

Weathering
• Two$types$of$weathering
• Mechanical$weathering$–$breaking$of$rocks into$smaller$pieces • Four$types$of$mechanical$weathering
• Frost$wedging$–$alternate$freezing$and$thawing of$water$in$fractures$and$cracks$promotes$the disintegra;on$of$rocks
"
"

"
"

Frost Wedging

Weathering
• Mechanical)Weathering,)con0nued
• Unloading)–)exfolia0on)of)igneous)and metamorphic)rocks)at)the)Earth’s)surface)due)to a)reduc0on)in)confining)pressure
• Thermal)expansion)–)alternate)expansion)and contrac0on)due)to)hea0ng)and)cooling • Biological)ac0vity)–)disintegra0on)resul0ng from)plants)and)animals "
"

Exfoliation of Igneous Rocks

Weathering
• Chemical)Weathering
• Breaks)down)rock)components)and)the internal)structures)of)minerals • Most)important)agent)involved)in)chemical weathering)is)water)(responsible)for transport)of)ions)and)molecules)involved)in chemical)processes) Weathering
• Major&processes&of&chemical&weathering
• Dissolu6on
• Aided&by&small&amounts&of&acid&in&the&water
• Soluble&ions&are&retained&in&the&underground water&supply • Oxida6on
• Any&chemical&reac6on&in&which&a&compound&or radical&loses&electrons "

Weathering
• Major&processes&of&chemical&weathering
• Oxida7on&con7nued
• Important&in&decomposing&ferromagnesian minerals • Hydrolysis
• The&reac7on&of&any&substance&with&water
• Hydrogen&ion&a>acks&and&replaces&other posi7ve&ions !

Weathering
• Altera'ons+caused+by+chemical+weathering
• Decomposi'on+of+unstable+minerals
• Genera'on+or+reten'on+of+materials+that are+stable • Physical+changes+such+as+the+rounding+of corners+or+edges Weathering
• Rates&of&weathering
• Advanced&mechanical&weathering&aids chemical&weathering&by&increasing&the surface&area
• Others&factors&affec:ng&weathering
• Rock&characteris:cs
• Rocks&containing&calcite&(marble&and&limestone) readily&dissolve&in&weakly&acidic&solu:ons Increase in Surface Area by Mechanical Weathering

Weathering
• Others'factors'affec-ng'weathering
• Rock'characteris-cs,'con-nued
• Silicate'minerals'weather'in'the'same'order'as their'order'of'crystalliza-on • Climate
• Temperature'and'moisture'are'the'most'crucial factors • Chemical'weathering'is'most'effec-ve'in'areas of'warm,'moist'climates "

Weathering
• Differen'al*weathering
• Masses*of*rock*do*not*weather*uniformly due*to*regional*and*local*factors • Results*in*many*unusual*and*spectacular rock*forma'ons*and*landforms Joint-controlled Weathering in Igneous Rocks

Soil
• Soil%is%a%combina,on%of%mineral%and%organic%mater, water,%and%air • That%por,on%of%the%regolith%(rock%and mineral%fragments%produced%by%weathering) that%supports%the%growth%of%plants
"
"

Typical Components in a Soil that Yield Good Plant Growth

Soil
• Factors(controlling(soil(forma/on
• Parent(material
• Residual(soil(–(parent(material(is(the(underlying bedrock • Transported(soil(–(forms(in(place(on(parent material(that(has(been(carried(from(elsewhere and(deposited

Soil
• Factors(controlling(soil(forma/on
• Time
• Important(in(all(geologic(processes
• Amount(of(/me(for(soil(forma/on(varies(for
Show More

Related Documents: Soil and Mechanical Weathering Essay

CCOT Essay

points) Part I: Soils (8 points) Using your textbook, module resources, and this website, http://school.discoveryeducation.com/schooladventures/soil/, answer the questions below: Define soil. An infinitely varying mixture of weathered mineral particles, decaying organic matter, living organisms, gases, and liquid solutions Provide a description of each of the following horizons: Ground level –Its where plants grow. a thick cover of plants keeps the soil cool and from dieing…

Words 1396 - Pages 6

Virginia Resources and Weathering/Soils Review Essay

Virginia Resources and Weathering/Soils Review Terms to know: Olivia Anderson Block One 12/12/11 Physiographic province-A landform region, an area delineated according to similar terrain that has been shaped by a common geologic history. Appalachian plateau-Coal mining Valley and ridge-Shenandoah Valley Blue ridge-Old, rounded mountains, Mount Rodgers Piedmont-“land at the foot of the mountains”, rolling hills, west of fall line Coastal Plain-(Tidewater), flat land, east of fall line…

Words 617 - Pages 3

Wind Weathering Lab Results

11/10/17 Period 1 Wind Weathering Background: Wind weathering is mostly found in a flat, bare, and dry area. It picks up soil, dust, and sand and carries them away as well as breaks them down into smaller and smaller pieces, for example, rocks. The wind erosion usually happens in the summer, spring, and fall. Mechanical Weathering is a physical breakdown of rocks into smaller and smaller pieces. In the picture below, the rock formation is caused from mechanical weathering, the pieces are exactly…

Words 515 - Pages 3

Biology 305 notes Essay examples

of plants can promote mechanical weathering by pushing into a rock, causing root wedging, widening fractures, and exposing it to elements that could further weather rock. Chemical weathering can be caused by roots, fungi getting into fractures, or encrust a rock produce acids that promote decomposition. Plants, however, prohibit erosion because the roots of the plants hold the soil together and help prevent soil from being moved by water, wind, rain. 2. Chemical weathering is predominant, basalt…

Words 576 - Pages 3

Sedimentary Rock Display Essay

effects of weathering and erosion. Each response must be at least 200 words. |Effects of Weathering |Effects of Erosion |What are the Differences? | |Weathering is the process of rock material |Erosion is when wind, water and ice |One difference between weathering and | |being broken up by air and water. One type |dislodge, dissolve or remove the materials |erosion is how humans can effect erosion | |is mechanical weathering…

Words 663 - Pages 3

Review H 2 3 Essay

th 8 Grade Science Test Review Ch 2-3 Oceans & Currents 1. What two factors affect the ocean’s surface temperatures? Two factors that affect the surface temperature of the oceans are latitude and time of the year. 2. Define salinity. Salinity is a measure of the amount of dissolved salts in given amount of liquid. 3. What two factors increase the salinity of ocean water? Evaporation and also if the water is slow moving it will have a higher salinity. 4. Explain how rivers cause the salinity of…

Words 881 - Pages 4

Essay on GEO 101 STUDY GUIDE WTK LIST 2

Garnero 1. Frost wedging is the major weathering process contributing to the formation of: TALUS SLOPES 2. Which two factors speed up rates of chemical reaction and weathering in rocks and soils? WARM TEMPERATURES; VERY MOIST 3. Which best describes sets of fractures in relatively fresh bedrock, such as granite, that are roughly parallel to the land surface? SHEETING FRACTURES 4. How do large, spheroidal boulders form from massive bedrock? CHEMICAL WEATHERING OCCURS MORE ON EDGES AND CORNERS. WHICH…

Words 940 - Pages 4

Essay about Geology exam 1

Geology Exam 1 The earth is a dynamic planet it is constantly evolving and we can see that on geologic time scale Chapter 5 1. What is a mineral? A naturally occurring solid formed by geologic process that has crystalline structure and definite chemical composition 2. What are the 8 most abundant minerals in the earths crust? (98.5%) a. Oxygen b. Silicon c. Aluminum d. Iron e. Calcium f. Sodium g. Potassium h. Magnesium 3. What is an ion? An atom with a net electric charge due to the loss or…

Words 2248 - Pages 9

Earth and Rock Classification Essay example

Preexisting rocks can be modified by heat, pressure and chemical agents to create new forms. 1. Distinguish between chemical and mechanical weathering, a short definition of economic mineralogy (page 136) Mechanical Weathering is the physical breakup of rocks into smaller particles without a change in chemical composition of the constituent minerals Chemical Weathering is the selective removal or alteration of specific components that leads to weakening and disintegration of rock. Economic Mineralogy:…

Words 619 - Pages 3

Essay about Science: Carbon Dioxide and Nitrogen

provide answers in a different color! Nitrogen Cycle: 1. What is the process called where nitrogen moves from the atmosphere to the ground? Nitrogen fixation Which organism(s)/process cause this to happen? Nitrogen fixing Bacteria that live in soil plants or water capture nitrogen from the air. 2. What type of bacteria performs nitrification? Nitrifying bacteria. Also Lightning. 3. What type of bacteria performs denitrification? Denitrifying bacteria 4. How do plants obtain the…

Words 800 - Pages 4