Volcanicity , temperatures

Question 1
(1) minerals
- hot underground water dissolve underground minerals
- after evaporation minerals are left on the ground

(2) hot spring, geyser, geothermal power
- as tourism
- spring minerals with medical value
- geothermal for electricity generation)

(3) fertile soil
- volcanic ash contain rich humus

(4) beautiful scenery
- faulting and folding are place with great tourism value
- promote economy and job opportunities

Question 2
- pollutant in air increase à absorb heat
- high buildings reduce ventilation and cause friction à reduce wind speed for evaporation (evaporation has an effect of cooling)
- albedo by concrete ground surface decreases and tend to absorb heat
- vegetation cover reduced à evaporation reduced (which has a function of reducing temperature)
- incomplete combustion by vehicles and industry à increasing amount of carbon dioxide in air which attract heat
- more counter-radiation at night, lower rate of temperature cooling at night


Question 3

In Cheng Chau, there are total seven beaches. The largest one is Tung Wan. When sand, peddles, shingle or mud deposit along a coast, a beach is formed. These deposits forms a gently sloping platform.
As mensioned above. a beach is the result of deposition. Materials broken off from the cliff accumulate at the base of the cliff. Then the contructive wave moves the sand and peddlesup the shore forming a beach. The material is further transported and deposited by long-shore drift. This shows mass wasting, constructive wave and long-shore drift all contribute to the formation of the beach.

However, beach in Tung Wan is mainly formed by tombolo.
Our sea carries all sorts of things on its ride, and this includes most importantly rocks and pebbles. However it is not always so strong to break away rocks from the shores, during some time of the year swash of the waves is stronger than its backwash and the pebbles are therefore left behind on the shore.
After a long time, with the help of long-shore drifts, sandspit is built along the coast, which acts as an obstacle to the waves, with its other end stretching into the sea.
Cheung Chau used to have two separate islands, one in the north and the other south. Spits were built on both islands and eventually as they grow they meet each other, joining the two islands as tombolo. (A beach is also found after deposition at east bay)

圖片參考：http://www.qc.edu.hk/it-school/homepage/geog/cheung%20chau/cheungchau_photo/ani-Tombolo-CC.gif


Question 4
- a concealed sea bay, deep water
- located in west of tombolo, away from strong easterly monsoon wind