NECO GCE 2016 Geography answer

am Time: 2:00Pm – 4:30Pm GEO Obj 1BBABCBDDDE 11CBCBDAAEDE 21BCEEEEECBA 31CEBBCAABBC 41ACCBADEEBD 51DBCDBABDAB =========== 1) Old scale=1:50,000 New scale=1:100.000 Reduction ratio= 50,000/100,000 =1/2. Oldscale=1:50,000 New scale=1:100.000 Reduction ratio= 50,000/100,000 =1/2. Length of map=36cm New length of map = 36*1/2 = 18cm Old breadth of map=34.1cm New breadth of map =34.1*1/2 =17.05cm ============ 2a) Revolut,ion is where the Earth travels, or revolves, around the Sun in a roughly circular path Each revolution takes the Earth around one complete orbit of the Sun, back to the same point a second time, and is called a year. It takes the Earth 365 days to complete it’s revolution around the sun. 2b) Tabulate i)Rotation refers to the Earth’s spin around its internal axis, while revolution refers to the Earth’s orbital motion around the sun. ii)The Earth rotates on its axis once every 24 hours and revolves around the sun once every 365.25 days. iii)Rotation of the earth causes day and night while Revolution causes seasons iv)Rotation causes dawn and twilight while Revolution causes Tides,waves 2c) i)it causes day and night ii)itcauses sunrise and sunset iii)causes dawn and twilight iv)causes different time zone in different places ============ (3ai) Block mountains are mountains that are formed from natural faulth in the earth crust DIAGRAM (3aii) Residual mountain can be defined as mountains formed out of existing mountain which have been eroded for millions of years DIAGRAM (3b) -It serves as a centre for tourist attraction -it leads to the formation of relief rainfall -it serves as a source of numerals -it also serve as sources of rivers which creates employment e.g.fishermen ============ (5a) Volcanicity is the process where molten magma or lava forces its way out from the earthscrust unto the earths surface. (5b) (i)Dyke:-this is sheet of of rock that is formed in the fracture in the pre – existing rock. Dyke form whena mass of magma cuts across the bedding planes and forms a wall like structure. Example of dyke is one that is found in Jos plateau in Nigeria this has been exposed to the surface through erosion. (ii)Sill:-this is formed when a sheet of magma lies along the bedding planes of the earth’s surface. A sill is therefore a horizontal sheet of rock that solidifies from magma that has been injected concordantly between bedding planes; they may be of any thickness and extend for many squareof kilometers. Example of sill is a great Whill sill in great Britain (iii)Batholith:-is large body of intrusive igneous rock believed to have been crystallized at the considerable depth below the earth’s surface..They are the largest type of pluton. Example of batholith is Idaho batholith which cover surface area of over 15500 kilometer square. (iv)Lopoliths these are saucer – shaped features formed beneath the earth’s surface through magma intrusion. Lopolith forms great shallow basin when magma solidifies within the crust a good example is bush veld igneous complex of south Africa which is composed of both granite and basic rock. 5c) i)carbonation- Carbon dioxide when dissolved in water it forms carbonic acid. 2H2O + CO2 -> H2CO3 This carbonic acid attacks many rocks and minerals and brings them into solution. The carbonated water has an etching effect up on some rocks, especially lime stone. ii)hydration- Chemical combination of water molecules with a particular substance or mineral leading to a change in structure. Soil forming minerals in rocks do not contain any water and they under go hydration when exposed to humid conditions. Up on hydration there is swelling and increase in volume of minerals. =============== (6b) (i)Trade wind deserts The trade winds in two belts on the equatorial sides of the Horse Latitudes heat up as they move toward the Equator. These dry winds dissipate cloud cover, allowing more sunlight to heat the land. (ii)Coastal deserts Coastal deserts generally are found on the western edges of continents near the Tropics of Cancer and Capricorn. They are affected by cold ocean currents that parallel the coast. Because local wind systems dominate the trade winds, these deserts are less stable than other deserts. (iii)Midlatitude deserts Midlatitude deserts occur between 30° and 50° N. and S., poleward of the subtropical highpressure zones. These deserts are in interior drainage basins far from oceans and have a wide range of annual temperatures. (6c) Coastal deserts Coastal deserts generally are found on the western edges of continents near the Tropics of Cancer and Capricorn. While Midlatitude deserts occur between 30° and 50° N. and S., poleward of the subtropical highpressure zones. =============== 7a) i)causes death to native animals, not only from lack of food and water, but also because drought can drive introduced species such as foxes and feral cats, which tend to be hardier than the native animals, to kill more native animals in the quest to survive ii)hinders a farmer’s income by limiting his ability to produce crops and/or healthy livestock iii)increases the danger of bushfires, duststorms and other drought-related natural disasters iv)land degradation – as plants die off, winds can quickly strip the land of topsoil; the natural habitat of native animals is damaged and some may not survive; wetlands and lakes may dry up 7b) i)Store water for future generations and Put more wells and tubewells ii)Develop irrigation facilities by building dams iii)Growing drought resistant crops like millets, maize and sorghum iv)Spraying water on the base of the plants so that less water is used ==============