JAMB UTME - Geography - 1999

Awọn alaye Idahun

When the gradient of a river channel changes from steep to gentle, the main activity of the river will be depositing. This means that the river will drop and deposit the sediments it has been carrying, such as sand, mud, and rocks, on the riverbed and along the banks. As the river slows down due to the decrease in gradient, it loses the energy required to transport the sediments, resulting in deposition. Deposition creates new landforms, such as sandbars and floodplains, which can support vegetation and wildlife habitats. Therefore, a decrease in gradient can lead to positive ecological effects.

Awọn alaye Idahun

The circulations of the oceans and the atmosphere play a crucial role in redistributing heat around the globe. The sun heats the equator more than the poles, creating temperature differences. The circulation systems move warm air and water from the equator towards the poles, and cold air and water from the poles towards the equator, balancing the global temperature. This helps regulate climate and weather patterns, which in turn support the growth and distribution of flora and fauna, including the production of oxygen by plants. Therefore, the correct option is heat.

Awọn alaye Idahun

Awọn alaye Idahun

Awọn alaye Idahun

The section labelled R most likely represents the continental slope. The continental slope is the steeply sloping area between the continental shelf and the ocean floor. It typically marks the boundary between the shallower, more gently sloping continental shelf and the deep ocean floor. The slope can vary in steepness, but generally, it is a relatively steep descent into deeper waters.

Awọn alaye Idahun

An example of a horst in Africa is the Ruwenzori Mountain Range, also known as the "Mountains of the Moon." A horst is a raised fault block bounded by normal faults on either side. The Ruwenzori range is located on the border between Uganda and the Democratic Republic of Congo and rises to an elevation of over 5,000 meters. It is one of the highest mountain ranges in Africa and is characterized by steep slopes, rugged terrain, and glacial lakes. The formation of the Ruwenzori range is due to the uplift of the horst block, which was caused by the movement of tectonic plates in the region. The horst formation process also led to the formation of other mountain ranges in Africa, including Kilimanjaro and Cameroon.

Awọn alaye Idahun

Awọn alaye Idahun

The most important gold mining town in Africa is Johannesburg. Johannesburg, also known as Joburg or Jozi, is the largest city in South Africa and is located in the Witwatersrand Basin, which is home to the world's largest gold deposit. Gold mining has been a major industry in the region since the late 1800s, and Johannesburg has become a hub for the mining and refining of gold. Today, the city is still a major center for gold mining, with several large companies operating in the area. The importance of Johannesburg to the gold mining industry has also made it a key financial and economic center for the continent of Africa. Other cities such as Obuasi in Ghana and Ilesa in Nigeria also have significant gold mining operations, but they are not as large or influential as Johannesburg. Bouake, on the other hand, is not known for its gold mining activities.

Awọn alaye Idahun

Awọn alaye Idahun

Fluid, basic lava flow is likely to give rise to a volcanic shield. A volcanic shield is a broad, gently sloping landform that is created by the accumulation of fluid lava flows. These lava flows are typically composed of basic lava, which has a low viscosity, or resistance to flow, and can travel great distances before solidifying. As the lava flows out of the volcanic vent, it spreads out in all directions, creating a broad, flat shield-shaped landform. Over time, the lava cools and solidifies, creating a new layer of rock. This process is repeated over many years, eventually resulting in the formation of a large, gently sloping volcanic shield. In contrast, a dome is a small, steep-sided volcanic landform that is created by the accumulation of highly viscous lava flows. A cinder cone is a steep-sided hill that is formed from explosive eruptions of ash and lava fragments. A saddle reef, on the other hand, is a type of mineral deposit that is found in geological formations. Therefore, fluid, basic lava flow is most likely to give rise to a volcanic shield.

Awọn alaye Idahun

Awọn alaye Idahun

Modern satellite towns are commonly characterized by a suburban location, a planned layout, and spacious surroundings. This means that they are located outside of the central city, have carefully designed street patterns and neighborhood layouts, and have plenty of open spaces such as parks and greenbelts. The houses in these towns are often roomy and set on large lots, and the overall building density is typically lower than in the central city. The goal of satellite towns is to provide a high quality of life for residents by offering a quieter, more spacious alternative to urban living while still being close enough to access the amenities of the central city.

Awọn alaye Idahun

To calculate the population density, we need to divide the total population by the land area. In this case, the total population is the sum of the number of males and females, which is 46 million + 41 million = 87 million. The land area is given as 173,000 square kilometers. So, the population density would be: Population density = Total population / Land area Population density = 87,000,000 / 173,000 Population density ≈ 503 persons per km2 Therefore, the average density of the population is approximately 503 persons per square kilometer.

Awọn alaye Idahun

A fog is most likely to develop when warm moist wind blows over a cold current. Fogs are formed when the air near the surface of the earth cools to its dew point, causing water vapor in the air to condense into tiny water droplets. This often happens when warm moist air encounters a cold surface, such as a cold ocean current or a cold front moving in. As the warm air cools near the cold surface, the water vapor in the air condenses into tiny water droplets, forming fog. In the case of warm moist wind blowing over a cold current, the warm moist air from the land or ocean meets the cold current, which causes the air to cool rapidly and form a fog.

Awọn alaye Idahun

Awọn alaye Idahun

Awọn alaye Idahun

Awọn alaye Idahun

Urban floods are mainly caused by the blockage of drains and waterways. Urbanization often leads to the construction of roads, buildings, and other impervious surfaces, which prevent rainwater from soaking into the ground. This runoff must be carried away through drains, gutters, and other waterways. If these channels are blocked or overwhelmed by the amount of water, flooding can occur. In urban areas, drains and waterways can become blocked by a variety of debris, including trash, leaves, and branches. In some cases, the infrastructure may not be sufficient to handle the amount of water produced during heavy rainfall. In addition, cities often have limited green spaces, which can help to absorb excess water. While the other options listed can contribute to flooding, they are not the primary cause of urban floods. The construction of dams and barrages, for example, can impact downstream flooding but is not a significant factor in urban flooding. The clearance of vegetation on farmlands and the establishment of shelter belts may contribute to flooding in rural areas, but are not major factors in urban flooding.

Awọn alaye Idahun

The harmattan wind in Nigeria is associated with the Tropical Continental Airmass. This is a dry and dusty air mass that originates from the Sahara desert in North Africa and moves southwards towards Nigeria during the months of November to February. The harmattan wind is characterized by its dryness, hotness, and dustiness. It causes a drop in humidity and a rise in temperature, which can lead to dry skin, cracked lips, and other health problems. The dust carried by the harmattan wind reduces visibility and can cause respiratory problems for people with asthma and other respiratory illnesses. It also affects agriculture, as the dry conditions can lead to crop failures and livestock deaths.

Awọn alaye Idahun

Environmentalists agree that there is a general rise in sea level as a result of global warming. As the Earth's temperature increases due to the release of greenhouse gases, such as carbon dioxide, into the atmosphere, the polar ice caps melt and the oceans expand, causing the sea level to rise. This rise in sea level has various consequences, such as flooding of coastal areas, displacement of people, and loss of habitats for marine animals.

Awọn alaye Idahun

The period when the earth is furthest from the sun is called Aphelion. The earth's orbit around the sun is not a perfect circle, but rather an elliptical shape. This means that at certain points in its orbit, the earth is closer to the sun, and at other points, it is farther away. Aphelion is the point in the earth's orbit when it is farthest away from the sun, which usually occurs in early July each year. During Aphelion, the earth is about 94.5 million miles away from the sun, which is about 3.1 million miles farther than it is during Perihelion, which is the point in the earth's orbit when it is closest to the sun.

Awọn alaye Idahun

Awọn alaye Idahun

The main use of an Abney level in survey is to determine the angle of inclination. An Abney level is a surveying instrument used to measure slopes, angles of inclination, and vertical angles. It consists of a sighting tube, a spirit level, and a graduated scale. To use the Abney level, the surveyor points the sighting tube towards the object whose angle of inclination needs to be measured. Then, they adjust the instrument until the spirit level shows that the instrument is level, and the graduated scale can be used to read the angle of inclination. Therefore, the main use of an Abney level in surveying is to determine the angle of inclination of an object, which is a critical measurement in engineering and construction projects.

Awọn alaye Idahun

A typical example of a landform produced by marine erosion is a stack. Marine erosion is the process by which the sea wears away at the land, resulting in the formation of various landforms. One of these landforms is a stack, which is a vertical column of rock that is isolated from the mainland. Stacks are typically found along coastlines where the sea has eroded the land around them, leaving them standing alone in the water. Stacks are formed when the sea erodes a headland, which is a narrow piece of land that juts out into the sea. Over time, the sea erodes the headland from both sides, eventually forming an arch. As the sea continues to erode the arch, it collapses, leaving a stack behind. While beaches, spits, and mud-flats are also landforms produced by marine erosion, they are not typical examples of landforms produced by this process. Beaches, for example, are typically formed by the deposition of sediment by the sea, while spits are narrow strips of land that extend from the coastline into the sea. Mud-flats are flat, muddy areas that are exposed during low tide.

Awọn alaye Idahun

One factor which helps to account for the dryness of the Sahara desert is the persistence of a high-pressure belt over the area. The Sahara desert is the largest hot desert in the world, covering over 3.6 million square miles of northern Africa. The area is characterized by extreme aridity, and one of the factors responsible for this is the persistence of a high-pressure belt over the region. This high-pressure belt creates a sinking air motion which inhibits the formation of clouds and results in little or no rainfall in the area. While the height of the jet stream over the area can influence the climate of the region, it is not a significant factor in the dryness of the Sahara desert. The complete absence of vegetation over much of the area is a consequence of the harsh climate and not a contributing factor to the dryness of the area. Also, the impact of oil production by the countries of that region is not a significant factor in the dryness of the Sahara desert. Therefore, the persistence of a high-pressure belt over the area is one factor which helps to account for the dryness of the Sahara desert.

Awọn alaye Idahun

Awọn alaye Idahun

Awọn alaye Idahun

The two dams found in the Upper and Lower Nile respectively are Aswan and Jebel Aulia. Aswan High Dam is located in Egypt, which is in the Lower Nile region, while Jebel Aulia Dam is situated in Sudan, in the Upper Nile region. Aswan High Dam is one of the largest dams in the world, constructed across the Nile River to control its flooding and generate hydroelectric power for Egypt. On the other hand, Jebel Aulia Dam is the largest dam in Sudan, built across the White Nile to regulate the flow of water for irrigation purposes in the surrounding region. These two dams play a significant role in regulating the flow of water in the Nile River, ensuring the availability of water for agriculture, hydroelectric power generation, and other uses in the two countries.

Awọn alaye Idahun

Expressways mainly help intracity traffic in that the multiple lanes can hold more traffic, and vehicles can move at high speed. Expressways are designed to handle a large volume of traffic, and they often have multiple lanes that allow for more vehicles to use the road at the same time. This can help to reduce congestion within the city, as vehicles are able to move more quickly and efficiently along the expressway. By reducing traffic congestion, expressways can also help to reduce air pollution and improve the overall quality of life for people living in the city. Additionally, because expressways provide a faster and more direct route between different parts of the city, they can also help to improve access to important services and amenities.

Awọn alaye Idahun

The heavy dark soil associated with floodable valley-bottoms is hydromorphic soil. Hydromorphic soil is also known as wetland soil and is characterized by its waterlogged nature. It is found in areas where the soil is frequently saturated with water, such as floodable valley-bottoms. Hydromorphic soil has a dark color due to the accumulation of organic matter, and it is also known to be very heavy, which makes it difficult to cultivate. On the other hand, lateritic soil is commonly found in areas with a tropical climate and has a reddish color, while ferrallitic soil is characterized by its yellowish or reddish color, and it is found in areas with a high concentration of iron and aluminum. Podzolic soil, on the other hand, is found in cold and humid regions, and it is characterized by its ash-gray color. Therefore, the heavy dark soil associated with floodable valley-bottoms is hydromorphic soil.

Awọn alaye Idahun

The drainage pattern of the area shown can be identified as dendritic. In a dendritic pattern, the river and its tributaries resemble the branching of a tree, with each small tributary feeding into larger ones as they flow towards the main river. The pattern typically forms on relatively flat-lying sedimentary rock or uniform material, where the rivers and streams erode through the terrain in a uniform fashion. This is the most common type of drainage pattern and can be found in many regions around the world.

Awọn alaye Idahun

International agreements in the fishing industry are necessary in order to protect whales and seals from stock extinction. Overfishing can lead to a depletion of fish populations, which in turn can have a ripple effect on the entire marine ecosystem, including the animals that depend on those fish as their primary food source. Whales and seals are particularly vulnerable to this kind of disruption, as they require large amounts of fish to sustain themselves. Without proper regulations and management, fishing fleets could continue to harvest fish at unsustainable rates, leading to a decline in populations and potentially putting these animals at risk of extinction. International agreements and regulations help to ensure that fishing activities are conducted in a sustainable and responsible manner, protecting the long-term health of the marine ecosystem and the animals that depend on it.

Awọn alaye Idahun

Awọn alaye Idahun

The group of people that is not found in West Africa is the Shona. The Wolof, Mandingo, and Mossi are all ethnic groups found in West Africa. The Wolof people are concentrated in Senegal, The Gambia, and Mauritania. The Mandingo people are found in Guinea, Mali, Senegal, The Gambia, Cote d'Ivoire, and other West African countries. The Mossi people are the largest ethnic group in Burkina Faso and are also found in Ghana, Ivory Coast, Mali, and Togo. On the other hand, the Shona people are an ethnic group primarily found in Zimbabwe and southern Zambia. Therefore, Shona is not found in West Africa.

Awọn alaye Idahun

Awọn alaye Idahun

Awọn alaye Idahun

The sequence of savanna vegetation zones in Nigeria towards the northern part is: Derived, Guinea, Sudan, and Sahel. The Derived savanna vegetation zone is found in the southern part of Nigeria, while the Guinea savanna zone is situated in the middle belt of Nigeria. The Sudan savanna vegetation zone is located in the northern part of Nigeria, and the Sahel savanna zone is found in the extreme northern part of Nigeria. So, the sequence of the savanna vegetation zones in Nigeria from south to north is Derived, Guinea, Sudan, and Sahel.

Awọn alaye Idahun

Awọn alaye Idahun

An extensive fertile plain with a relatively low population will most likely be characterized by scattered rural settlements. This is because the plain is fertile and can support agriculture, which will provide food for the people. Since the population is low, there will not be a high demand for land and there will be enough space for people to settle and cultivate the land. The settlements will be scattered across the plain and may be small villages or hamlets, rather than large towns or cities.

Awọn alaye Idahun

Awọn alaye Idahun

The three ethnic groups of the Niger Delta region of Nigeria are Ijo, Urhobo, and Itshekiri. The Ijo people are one of the major ethnic groups in the Niger Delta region of Nigeria, and they are spread across several states in the region. The Urhobo people are also a significant ethnic group in the Niger Delta region and are mainly found in Delta State. The Itshekiri people are another prominent ethnic group in the Niger Delta, mainly located in Warri, Delta State. Therefore, the three ethnic groups of the Niger Delta region of Nigeria are Ijo, Urhobo, and Itshekiri.

Awọn alaye Idahun

Awọn alaye Idahun

The vegetation of the warm Temperate Eastern Margin is characterized by mixed deciduous and coniferous forests. The warm Temperate Eastern Margin is a region characterized by mild temperatures and high rainfall. This climate is ideal for the growth of a wide variety of trees and plants, leading to the development of mixed deciduous and coniferous forests. These forests are characterized by a mixture of trees that shed their leaves in the fall (deciduous) and trees that retain their needles year-round (coniferous). The deciduous trees include oak, maple, and beech, while the coniferous trees include pine, spruce, and fir. These mixed forests support a diverse range of wildlife, including deer, bears, and numerous bird species. They are also important for human activities such as logging and recreation. Therefore, the vegetation of the warm Temperate Eastern Margin is characterized by mixed deciduous and coniferous forests, which are a unique and valuable ecosystem.

Awọn alaye Idahun

The set of trees most suitable for pulp and paper making is spruce, fir, and pine. These trees are known for having long and straight trunks, which makes them easy to cut into small pieces for pulping. They also have high levels of cellulose, which is the main component of paper. Furthermore, they have low levels of lignin, which is a substance that can negatively impact the quality of paper. Because of these qualities, spruce, fir, and pine are commonly used in the paper-making industry.

Awọn alaye Idahun

Awọn alaye Idahun

Awọn alaye Idahun

Many industries in Europe and America have established branches in South East Asia in order to reduce production costs. This is because labor and other production costs are usually lower in South East Asia compared to Europe and America. By establishing branches in South East Asia, these industries can take advantage of the lower production costs and increase their profit margins. This trend is commonly known as outsourcing, where companies relocate their operations to countries where costs are lower.

Awọn alaye Idahun

Soils with well-developed profiles formed mainly under the influence of the regional climate and vegetation are said to be zonal. The term "zonal" refers to the fact that these soils are characteristic of a particular zone or region, and their properties are largely determined by the regional climate and vegetation. This type of soil formation typically occurs in areas where the climate is relatively stable and the vegetation is well-established, allowing for the development of a distinct soil profile over time. Zonal soils are often deep, well-drained, and rich in organic matter, and they may be associated with specific types of vegetation, such as forests or grasslands. In contrast, azonal soils are soils that are not well-developed due to limitations such as steep slopes, rocky terrain or recent deposition, while intrazonal soils are soils that develop due to factors such as excess moisture or high acidity that are not directly related to the regional climate and vegetation. Colluvial soils, on the other hand, are soils that have been formed through the accumulation of material that has moved downslope due to the force of gravity.