What 2 factors determine the rate of weathering?
Rainfall and temperature can affect the rate in which rocks weather. High temperatures and greater rainfall increase the rate of chemical weathering. 2. Rocks in tropical regions exposed to abundant rainfall and hot temperatures weather much faster than similar rocks residing in cold, dry regions.
What weathering forms cracks in granite?
Solid rock, like this granitic outcrop on Mount San Jacinto in southern California, fractures into blocks by forces of mechanical weathering. Every day, water seeps into cracks in the granite. Every night the cracks expand as the water freezes. Then, the next day, water trickles further into the expanded crack.
What is the weathering product of granite?
As demonstrated in the following reaction, this causes potassium feldspar to form kaolinite, with potassium ions, bicarbonate, and silica in solution as byproducts. An end product of granite weathering is grus, which is often made up of coarse-grained fragments of disintegrated granite.
What are the final weathered products of granitic rocks?
The clay gradually gets eroded away, then the rock breaks apart leaving lots of grains of quartz. In other words, quartz, clay minerals, and dissolved ions are the most common products of weathering….5.3 The Products of Weathering and Erosion.
| Common Mineral | Typical Weathering Products |
|---|---|
| Biotite and amphibole | Chlorite plus iron and magnesium in solution |
What are the rates of weathering?
The weathering rate for rocks depends on the composition of the rock; the climate of the area; the topography of the land; and the activities of humans, animals, and plants. A rock's composition has a huge effect on its weathering rate. Rock that is softer and less weather-resistant tends to wear away quickly.
What are the 3 factors that influence the rate of weathering?
Generally, interactions with air, water and living organisms cause the weathering of rocks. Although there are two major types of weathering processes, physical weathering and chemical weathering cannot be separated, and they often work together at different rates to break large rocks into smaller pieces over time.
Which rock weathers the most slowly?
They are sheet silicate minerals like micas. Quartz chemically weathers only very, very slowly because of its high stability. It is mostly just broken down into small, sand-sized and smaller particles. Rock fragments will also remain where the rocks are not completely weathered.
Why is granite weathering resistant?
Granite is extremely resistant and sandstone a little less so due to the percentage of quartz that each rock type contains. Granite is extremely hard and less affected by the freeze-thaw cycle, the forces of abrasion and the surface exfoliation processes that are all a part of physical weathering.
What is the most common type of weathering?
One of the most common types of physical weathering is wedging. Wedging occurs when a substance finds its way into cracks or holes in rock and expands outward.
Which of the following is true about how weathering affects fractured rocks?
Which of the following is true about how weathering affects fractured rocks? –Weathering affects rocks from the outside in, forming an outer weathered zone or rind.
Which area is experiencing the greatest amount of weathering?
CLIMATE: The amount of water in the air and the temperature of an area are both part of an area's climate. Moisture speeds up chemical weathering. Weathering occurs fastest in hot, wet climates. It occurs very slowly in hot and dry climates.
Which rock weathers most quickly?
limestone Sedimentary rocks usually weather more easily. For example, limestone dissolves in weak acids like rainwater. Different types of sedimentary rocks can weather differently.
What is the most important factor in weathering?
Climate: This is the most important factor affecting weathering of rocks. The extent of weathering is dependent on the average atmospheric condition prevailing in a region over a long period of time.
Which rock weathers more quickly?
Rocks made up of minerals such as feldspar, calcite, and iron, weather more quickly. 4. Pollution speeds up weathering. Factories and cars release carbon dioxide and other gases into the air.
Which condition leads to slower rate of weathering?
Cold climates favor mechanical weathering. Chemical reactions occur slower at higher temperatures. Lower precipitation levels lead to more chemical reactions. The chemical reaction rates of minerals are not impacted by temperature.
Which rock layer is most resistant to weathering?
Igneous rocks are usually solid and are more resistant to weathering. Intrusive igneous rocks weather slowly because it is hard for water to penetrate them. Sedimentary rocks usually weather more easily. For example, limestone dissolves in weak acids like rainwater.
Which rock is most resistant to weathering?
Quartz is known to be the most resistant rock- forming mineral during surface weathering.
What climate types cause more intense weathering?
A warm, wet climate will produce the highest rate of weathering. The warmer a climate is, the more types of vegetation it will have and the greater the rate of biological weathering (Figure below). This happens because plants and bacteria grow and multiply faster in warmer temperatures.
What are the two most common forms of weathering?
Weathering is often divided into the processes of mechanical weathering and chemical weathering.
What rock type is the most common setting for caves formed by dissolution of a rock?
limestone As previously noted, the largest and most common caves are those formed by dissolution of limestone or dolomite. Limestone is composed mostly of calcium carbonate in the form of the mineral calcite. Dolomite rock consists of calcium magnesium carbonate, the mineral dolomite.
What happens to the surface area of exposed rock If a rock is fractured?
What happens to the surface area of exposed rock if a rock is fractured? The surface area increases as the rock is fractured.
In which region would you expect to highest weathering quizlet?
What portion of an angular, fracture-bounded granitic block shows the highest rate of weathering? The edges and corners.
What climatic region would you expect to find the highest rates of weathering?
The wet conditions of the tropics allows the chemical reactions of weathering to take place at all, while the heat in this region speeds up the process of weathering. What climatic region would you expect to find the lowest rates of weathering?
Does granite weather easily?
Igneous rocks, especially intrusive igneous rocks such as granite, weather slowly because it is hard for water to penetrate them. Other types of rock, such as limestone, are easily weathered because they dissolve in weak acids.
What is the rate of weathering?
The weathering rate for rocks depends on the composition of the rock; the climate of the area; the topography of the land; and the activities of humans, animals, and plants. A rock's composition has a huge effect on its weathering rate. Rock that is softer and less weather-resistant tends to wear away quickly.
How does surface area affect the rate of weathering?
Large rocks have less surface area for their volume than small rocks. Therefore a smaller portion of the rock is exposed to weathering. It takes longer for the rock to wear away. The small rock has more surface area for its vol- ume so it weathers away faster.
Is granite resistant to weathering?
Rocks that contain quartz stand up well to the forces of chemical weathering. Granite is extremely resistant and sandstone a little less so due to the percentage of quartz that each rock type contains.
Which environment would typically have the highest rate of weathering and erosion?
Climate- High amounts of water and higher temperatures generally cause chemical reactions to run faster. Thus warm humid climates generally have more highly weathered rock, and rates of weathering are higher than in cold dry climates.
Which condition leads to a slower rate of weathering quizlet?
The dry climate promotes a slower rate of weathering.
What rock type is most easily weathered?
Igneous rocks, especially intrusive igneous rocks such as granite, weather slowly because it is hard for water to penetrate them. Other types of rock, such as limestone, are easily weathered because they dissolve in weak acids.