Topographical Maps
EXERCISE
1. Answer the following questions in about 30 words:
(i) What are topographical maps?
Ans: Topographical maps are detailed blueprints of Earth's surface, showing natural features like mountains, valleys, rivers, and even elevations, like tiny contour lines, revealing the land's 3D shape! They're like mini atlases for specific areas, helping you navigate terrain and understand the landscape.
(ii) Name the organisation which prepares the topographical maps of India.
Ans: My apologies! The answer to your question is Survey of India. They are the national survey and mapping organization responsible for creating topographical maps of India. 🇮🇳 ️
(iii) Which are the commonly used scales for mapping our country used by the Survey of India?
Ans: Survey of India commonly uses several scales for mapping India, including:
*1:100,000 (largest scale): Detailed regional maps.
*1:250,000: State-level maps and tourist maps.
*1:50,000: Popular scale for detailed topographic maps.
*1:25,000: Highly detailed maps for specific areas.
Remember, larger scale maps provide greater detail but cover smaller areas. Choose the scale based on your specific needs and the level of detail desired.
(iv) What are contours?
Ans: Contours are like imaginary elevation lines on a map, connecting points of equal height above a chosen level (often sea level). Imagine tiny "footprints" tracing the hills and valleys, revealing the land's 3D shape! They help you understand slopes, heights, and even plan safe routes over terrain.
(v) What does the spacing of contours indicate?
Ans: Closely spaced contours? Think steep climbs! Widely spaced? Gentle slopes ahead. The distance between contours on a map tells you how much elevation changes over that space, revealing the steepness of the terrain. Imagine climbing stairs - lots of steps in a short distance mean a steeper climb!
(vi) What are conventional signs?
Ans: Conventional signs are like miniature symbols on maps representing real-world features. Think tiny trees for forests, blue lines for rivers, and triangles for mountains. They let you quickly understand what you're looking at on a map without needing words for everything! ️️️️️
2. Write short notes on—
(i) Contours
Ans: Contours: Mini mountains on your map!
What they are:
*Imaginary lines on maps connecting points of equal elevation.
*Think of them as "footprints" tracing the land's hills and valleys.
*Used to understand slopes, heights, and plan routes.
Reading the clues:
*Spacing: Closely spaced = steep slopes, widely spaced = gentle slopes.
*Direction: Uphill goes towards closed loops, downhill goes away.
*Intersect: Crossing contours = valley or ridge.
Benefits:
*Reveal 3D shape of the land without pictures.
*Help calculate elevation and slope angles.
*Essential for engineers, hikers, and explorers.
Remember:
*Contours are like a simplified language, learn their "grammar" to navigate the map world!
(ii) ‘Marginal Information’ in Topographical sheets
Ans: Marginal Information: The Map's Passport
Marginal information is the crucial data printed around the edges of a topographical sheet, offering vital information about the map itself:
Key elements:
*Sheet number & name: Identifies the specific map location.
*Grid references: Links the map to a larger national grid system.
*Extent in degrees: Precise latitude and longitude coverage.
*Scale: Ratio between map distances and real-world distances.
*Contour interval: Vertical difference represented by each contour line.
*Legend: Explanation of conventional symbols used on the map.
*Year of survey & publication: Indicates map's currency and reliability.
*Additional details: May include district names, neighboring sheets, etc.
Importance:
*Provides context and understanding of the map area.
*Facilitates cross-referencing with other maps and data sources.
*Enables accurate measurement of distances and elevations.
*Ensures proper interpretation of symbols and features.
Think of it as the map's passport: it tells you where it comes from, what it covers, and how to read its language. So next time you unfold a topographical sheet, don't skip the edges - the marginal information is waiting to unlock the map's secrets!
(iii) The Survey of India
Ans: Survey of India: Mapping India's Pulse
The Survey of India (SOI) is the national survey and mapping organization of India, carrying a rich legacy of over 250 years. Here's a quick overview:
What they do:
*Create topographical maps of India at various scales, revealing the land's 3D shape through contours and symbols.
*Conduct geodetic surveys to establish precise control points for accurate mapping and other applications.
*Provide geospatial data for diverse sectors like infrastructure, disaster management, and environmental studies.
*Train specialists in surveying and mapping through their premier institute, National Institute for Geo-informatics Science & Technology (NIGST).
Importance:
*Their maps are crucial for navigation, planning, and development across India.
*SOI data feeds into various government applications like border management and resource planning.
*Their expertise contributes to scientific research and technological advancement in geospatial fields.
Fun facts:
*Established in 1767, it's one of the oldest scientific departments in India.
*SOI's headquarters are in Dehradun, known as the "City of Surveyors."
*They use cutting-edge technologies like LiDAR and drones for modern mapping.
3. Explain what is meant by ‘map interpretation’ and what procedure is followed for its interpretation.
Ans: Map interpretation is the art of extracting meaningful information and insights from a map, going beyond visual observation to uncover the stories hidden within its symbols and patterns.
Here's a concise guide to the procedure for map interpretation:
1. Gather Context:
*Examine the marginal information (title, scale, legend, date).
*Understand the map's purpose and intended audience.
2. Analyze Visual Elements:
*Identify key features (symbols, colors, patterns, contours).
*Recognize relationships and patterns between features.
3. Interpret Symbols:
*Use the legend to decode symbols and represent real-world features.
*Understand the meaning of colors and line types.
4. Visualize Spatial Relationships:
*Grasp the relative positions of features (distances, directions).
*Imagine the 3D terrain using contours and visual cues.
5. Integrate Information:
*Combine visual analysis with prior knowledge of the area or topic.
*Consider geographic concepts (topography, hydrology, human patterns).
6. Draw Conclusions:
*Form inferences and conclusions based on the map's data.
*Identify trends, patterns, or relationships.
7. Communicate Findings:
*Present findings clearly and concisely, using appropriate tools (maps, charts, text).
*Tailor communication to the audience's understanding.
4. If you are interpreting the cultural features from a topographical sheet, what information would you like to seek and how would you derive this information? Discuss with the help of suitable examples.
Ans: Interpreting cultural features from a topographical sheet involves extrapolating beyond the physical landscape to understand human presence and activity. Here's what I would look for and how to derive information:
1. Settlements & Networks:
*Location: Look for symbols representing settlements (villages, towns, cities) and analyze their distribution: clustered near water/resources? Along transportation routes? Isolated?
*Pattern: Notice the layout of settlements (linear, circular, grid) which might indicate historical development, cultural practices, or adaptation to the environment.
*Connectivity: Identify transportation networks (roads, railways, rivers) connecting settlements and understand how they influence interaction and trade.
Example: A clustered settlement near a river with radiating roads suggests a historical focus on agriculture and trade via waterways.
2. Land Use & Resources:
*Topography: Analyze how contour lines and elevation patterns are associated with agricultural areas, grazing lands, or forests. Look for marks depicting specific crops or natural resources.
*Symbols: Identify symbols for dams, mines, quarries, or power plants, indicating resource extraction or industrial activity.
*Changes over time: Compare older editions of the topographical sheet, if available, to observe changes in land use patterns, suggesting development or shifts in economic focus.
Example: Extensive farmland on flat terrain near a river points to agriculture as a primary livelihood, while symbols and elevation changes could reveal a nearby hydroelectric dam project.
3. Religious & Cultural Landmarks:
*Symbols: Look for religious symbols like temples, mosques, churches, or burial grounds, indicating cultural diversity and historical presence.
*Festivals & Events: Research local festivals or cultural events linked to specific topographic features (hills, rivers, caves) to understand their spiritual significance.
*Naming Conventions: Analyze place names for hints about local languages, historical figures, or cultural practices associated with the area.
Example: A mountain peak named after a deity and marked with a temple symbol suggests religious importance and potential pilgrimage routes.
Remember, interpreting cultural features is not an exact science but relies on deduction and contextual knowledge. By combining information from the map with research and local insights, you can gain valuable perspectives on the human interactions and history woven into the landscape.
5. Draw the conventional signs and symbols for the following features—
(i) International Boundary
(ii) Bench Mark
(iii) Villages
(iv) Metalled Road
(v) Footpath with bridges
(vi) Places of Worship
(vii)Railwayline
Exercise A
Study the contour pattern and answer the following questions.
1. Name the geographical feature formed by contours.
2. Find out the contour interval in the map.
3. Find out the map distance between E and F and convert it into ground
distance.
4. Name the type of slope between A and B; C and D and E and F.
5. Find out the direction of E, D and F from G.
Exercise B
Study the extract from the topographical sheet No. 63K/12, as shown in
the figure below and answer the following questions—
1. Convert 1:50,000 into a statement of scale.
2. Name the major settlements of the area.
3. What is the direction of flow of the river Ganga?
4. At which one of the banks of river Ganga, Bhatauli is located ?
5. What is the pattern of rural settlements along the right bank of river
Ganga?
6. Name the villages/settlements where Post Office is located ?
7. What does the yellow colour in the area refer to?
8. What means of transportation is used to cross the river by the people
of Bhatauli village ?
Exercise C
Study the extract for topographical sheet 63K/12 shown in the figure on
page 68 and answer the following questions.
1. Give the height of the highest point on the map.
Ans:
2. River Jamtihwa Nadi is flowing through which quarter of the map ?
3. Which is the major settlement located in the east of the Kuardari Nala ?
4. What type of settlement does the area have ?
5. Name the geographical feature represented by white patches in the middle of Sipu Nadi.
Ans:
6. Name the two types of vegetation shown on part of the topographical
sheet.
7. What is the direction of the flow of the Kuardari ?
8. In which part of the sheet area is Lower Khajuri Dam located?
Answer By: Himashree Bora.
