Sulphur dioxide also reacts with calcium carbonate which is a main component of limestone. This causes limestone buildings to develop a soft outer crust which in time is likely to exfoliate. This has happened to the building of Oxford university which are largely made up of limestone. Here acid rain is dominant and the university loses much money each year in order to sustain it’s buildings.
Weathering also occurs on roads throughout the UK, in the main as a result of there being extremely cold temperatures. This causes the roads to become slippery and so to deal with the problem salt grit is placed onto the roads. The salt crystallises and hydrates through the pores within underlying material causing salt crystal growth. This mechanical weathering exerts pressure on surrounding areas when water is heated and hence evaporates leaving the salt behind. The result is a pitted and uneven road surface that in time will need to be replenished due to its unsuitability for driving on and thus this costs large amounts of money. This process is also very common in arid coastal regions of Greece and Turkey which water is very quickly evaporated and leaves behind growing salt crystals.
Freeze thaw weathering also impacts human activity because it degrades road surface quality. In Scotland for example due to the cold and icy climate freeze-thaw is a dominant process whereby water will get into cracks and fractures in the rock and expand during colder times by 9.05% (usually nights) and melts in warmer temperatures (usually day times). This again results in the roads having an uneven surface which are hard to drive on and an economic burden for the future.
Weathering also has positive impacts. Yosemite Valley in California has generated vast sums of incomes as a result of the dominant exfoliation occurring there.
The white granite domes and cliffs like which are like half domes, are as a result of the exfoliation. These rocks were molten plutons, deep underground, raising the Sierra Nevada range. Erosion then unroofed the plutonic rocks and took away the pressure of the overlying rock. As a result, the solid rock acquired fine cracks through pressure-release jointing.
The combined work of gravity, weathering, plant roots, and the expansion of freezing water opened up the joints further and loosened these slabs. The landforms created are popular with people across the developed world and has attracted much tourism to the area. Around 3.7 million people stay in the cabins and hotels within the park every year.
In Java the weathering of volcanic ash has given rise to fertile soils. This has helped to produce very productive agriculture. About 40% of the cultivated land consists of rice terraces, while major commercial crops include rubber, coffee, tea, sugar, quinine, tobacco, cacao, and timber. Mineral wealth includes petroleum, coal, tin, gold, and silver. Industries on the island at centres such as Jakarta and Surabaya are largely based on the processing of these agricultural and mineral products, with the addition of timber processing, chemicals, shipbuilding, and motor vehicle assembly. This will no doubt have allowed the people living there to sustain their living needs and also make money from selling excess as commercial produce.
Weathering in southwest England, in particular Dartmoor has created China clay. The granitic rock there containing feldspar s decomposed by hydrolysis to form the white clay Kaolin. China clay production in Southwest England was estimated at 150million tonnes by the year 1998. This material is used to produce porcelain ceramics and paper. It is employed in natural and synthetic rubber compounds, plastics, white cement, glass fibre, fertilisers, pesticides, weed killers, paints and protective coatings, crayons, cosmetics, medicines, and new uses are constantly being developed. This opens up many industries for the UK which undoubtedly contributes to a reasonable sum of the UK’s annual real GDP.
Overall, it be seen that weathering gives both advantages and disadvantages to human activity in a variety of ways.
