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TABLE OF CONTENTS

1. INTRODUCTION: ..................................................................................................................... 4

2. CONCEPT AND CATEGORIZATION OF MAP: .................................................................... 4

3. BASIC ELEMENTS OF TOPOGRAPHIC MAPS: ................................................................... 5

4. METHODS OF SHOWING RELIEF ......................................................................................... 7

5. DEFINITION OF IMPORTANT TOPOGRAPHIC TERMS: ................................................... 8

6. HOW TO DETERMINE A SLOPE: ........................................................................................ 10

7. INTERPRETATION OF TOPOGRAPHIC MAP: ................................................................... 11

7.1: PROVIDED MAP.............................................................................................................. 11

7.2: PHYSICAL ANALYSIS OF THE SUPPLIED MAP ....................................................... 11

7.3: CULTURAL INFORMATION OF THE SUPPLIED MAP ............................................. 12

7.4: ANALYSIS BETWEEN THE PHYSICAL AND CULTURAL RELATIONS OF THE

SUPPLIED MAP ...................................................................................................................... 13

7.5: PREDICTION AFTER 24 YEARS ................................................................................... 14

8. GEOLOGIC MAP AND ITS TYPES....................................................................................... 17

9. IMPORTANCE OF GEOLOGIC MAP: .................................................................................. 18

10. USES OF GEOLOGIC MAPS: .............................................................................................. 19

11. STAGES TO FORM A GEOLOGIC MAP: ........................................................................... 21

12. DEFINITION OF IMPORTANT GEOLOGIC TERMS:....................................................... 24

13. WEATHER MAP ................................................................................................................... 28

14. SIGN AND SYMBOL OF A WEATHER MAP:................................................................... 29

15. DIFFERENCE BETWEEN WEATHER AND CLIMATE: .................................................. 39

16. CONCLUSION: ...................................................................................................................... 40

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LIST OF FIGURES

LIST OF TABLES

Table Page

Table-1: Difference between Weather and Climate 40

LIST OF MAPS

Map Page

Map 1: Geologic map of Bangladesh 20

Map 2: Current Weather map of Bangladesh 28

Attached map from provided sample 12

Figure Page

Figure 1: Basic Elements of a Topographic Map 6

Figure 2: Contour lines. 7

Figure 3: Layer Tinting 8

Figure 4: Spot Height 8

Figure 5: Bench Mark 9

Figure 6: Trigonometrical Station 9

Figure 7: Major fault lines of the world 9

Figure 8: Lithology of Outcrop and Field Structure Sketch. 22

Figure 9: Strike/Dip Data Plot and Indication of Geology Structure. 22

Figure 10: Data Plot on 25° 23

Figure 11: How to Make Cross Section 24

Figure 12: Hutton Unconformity 25

Figure 13: A Faulting in Morocco 26

Figure 14: Strike 26

Figure 15: Time symbol 29

Figure 16: High and Low Pressure Centre 30

Figure 17: Isobar 31

Figure 18: Weather Fronts and Features 32

Figure 19: Weather Station Plot 33

Figure 20: Weather Map Symbols for Current Weather 34

Figure 21: Sky Cover Symbols 35

Figure 22: Weather Map Symbols for Clouds 36

Figure 23: Wind Direction and Wind Speed Symbols 37

Figure 24: Precipitation Areas and Symbols 38

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SECTION-1:

TOPOGRAPHIC MAP

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1. INTRODUCTION: Map study is the essential part for studying geography and gaining advance and basic knowledge

of cartography as well. There are several sorts of map such as topographic map, thematic map,

geologic map, weather map etc. Details of the study of maps are discussed throughout this

notebook. Also the provided sample in the cartographic lab has been analyzed and attached with

the notebook.

2. CONCEPT AND CATEGORIZATION OF MAP: A map is a symbolic depiction emphasizing relationships between elements of some space, such

as objects, regions, or themes. Geographic map is the study and practice of crafting

representations of the Earth upon a flat surface.

Road maps are perhaps the most widely used maps today, and form a subset of navigational

maps, which also include aeronautical and nautical charts, railroad network maps, and hiking and

bicycling maps. In terms of quantity, the largest number of drawn map sheets is probably made

up by local surveys, carried out by municipalities, utilities, tax assessors, emergency services

providers, and other local agencies.

There are several types of maps. Such as-

i. POLITICAL MAPS: A political map does not show topographic features like

mountains. It focuses solely on the state and national boundaries of a place. They also

include the locations of cities large and small, depending on the detail of the map.

ii. PHYSICAL MAPS: A physical map is one documents landscape features of a place.

They generally show things like mountains, rivers, and lakes. Bodies of water are always

shown with blue. Mountains and elevation changes are usually shown with different

colors and shades to show relief. Normally on physical maps, green shows lower

elevations while browns show high elevations.

iii. TOPOGRAPHIC MAPS: A topographic map is similar to a physical map in that it

shows different physical landscape features. Unlike physical maps, this type of may uses

contour lines instead of colors to show changes in the landscape. Contour lines on

topographic maps are normally spaced at regular intervals to show elevation changes (e.g.

each line represents a 100-foot (30 m) elevation change) and when lines are close

together the terrain is steep.

iv. CLIMATE MAPS: A climate map shows information about the climate of an area. They

can show things like the specific climatic zones of an area based on the temperature, the

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amount of snow an area receives or the average number of cloudy days. These maps

normally use colors to show different climatic areas.

v. ECONOMIC OR RESOURCE MAPS: An economic or resource map shows the

specific types of economic activity or natural resources present in an area through the use

of different symbols or colors depending on what is being shown on the map.

vi. ROAD MAPS: A road map is one of the most widely used map types. These maps show

major and minor highways and roads (depending on detail), as well as things like

airports, city locations and points of interest such as parks, campgrounds, and

monuments. Major highways on a road map are generally shown in red and larger than

other roads, while minor roads are a lighter color and a narrower line.

vii. THEMATIC MAPS: A thematic map is a map that focuses on a particular theme or

special topic. They are different from the six aforementioned general reference maps

because they do not just show natural features like rivers, cities, political subdivisions,

elevation, and highways. If these items are on a thematic map, they are background

information and are used as reference points to enhance the map's theme.

3. BASIC ELEMENTS OF TOPOGRAPHIC MAPS: The basic elements of a topographic map are discussed below.

1. Title: A topographic map must have a title expressing the primary purpose of drawing

the map at the top corner of the map.

2. Coordinate system: Topographic map must have coordinate system showing the latitude

and longitude. A topographic map May have more than one grid system. Latitude is at the

top and bottom of the map and longitude is found at the both sides of the map.

3. Contour lines: A contour line is the imaginary horizontal line that connects all points in

a field which have the same elevation. A contour line is imaginary but can be visualized

by taking the example of a lake. The water level of a lake may move up and down, but

the water surface always remains horizontal. The level of the water on the shore line of

the lake makes a contour line because it reaches points which are all at the same

elevation.

4. Indicating Color: A topographic map should have some indicating colors such as-blue

for water, green for forest, brown for contour lines, black for cultural features etc.

5. Direction: Like other maps, topographic map should show the direction points such as

northwards or magnetic declination from northwards.

6. Slopes: A slope is the rise or fall of the land surface. It is important for the farmer or

irrigator to identify the slopes on the land.

7. Elevation of a point: Any sort of elevation of a point should be shown in the topographic

map.

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8. Depression of a point: The depression of any point should be shown in the topographic

map in the same way of showing an elevation point.

9. Other elements: The topographic map has other elements of a map such as scale, legend,

boundary, RF etc.

The following legend is a sample showing the various elements of a topographic map.

Figure 1: Basic Elements of a Topographic Map

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4. METHODS OF SHOWING RELIEF Mapmakers use several methods to depict relief of the terrain.

a. Layer Tinting. Layer tinting is a method of showing relief by color. A different color is used

for each band of elevation. Each shade of color, or band, represents a definite elevation range. A

legend is printed on the map margin to indicate the elevation range represented by each color.

However, this method does not allow the map user to determine the exact elevation of a specific

point—only the range.

b. Form Lines. Form lines are not measured from any datum plane. Form lines have no

standard elevation and give only a general idea of relief. Form lines are represented on a map as

dashed lines and are never labeled with representative elevations.

c. Shaded Relief. Relief shading indicates relief by a shadow effect achieved by tone and

colors that result in the darkening of one side of terrain features, such as hills and ridges. The

darker the shading, the steeper the slope. Shaded relief is sometimes used in conjunction with

contour lines to emphasize these features.

d. Hachures. Hachures are short, broken lines used to show relief. Hachures are sometimes

used with contour lines. They do not represent exact elevations, but are mainly used to show

large, rocky outcrop areas. Hachures are used extensively on small-scale maps to show mountain

ranges, plateaus, and mountain peaks.

e. Contour Lines. Contour lines are the most common method of showing relief and elevation

on a standard topographic map. A contour line represents an imaginary line on the ground, above

or below sea level. All points on the contour line are at the same elevation. The elevation

represented by contour lines is the vertical distance above or below sea level. The three types of

contour lines used on a standard topographic map are as follows:

Figure 2: Contour lines.

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(1) Index. Starting at zero elevation or mean sea level, every fifth contour line is a heavier line.

These are known as index contour lines. Normally, each index contour line is numbered at some

point. This number is the elevation of that line.

(2) Intermediate. The contour lines falling between the indexes contour lines are called

intermediate contour lines. These lines are finer and do not have their elevations given. There are

normally four intermediate contour lines between index contour lines.

(3) Supplementary. These contour lines resemble dashes. They show changes in elevation of at

least one-half the contour interval. These lines are normally found where there is very little

change in elevation, such as on fairly level terrain.

5. DEFINITION OF IMPORTANT TOPOGRAPHIC TERMS: There are some important terms that need to be defined before incepting a in-depth discussion

about the map study. Those are defined below.

Layer Tinting: A method of showing relief on

maps and charts by coloring different levels in

different shades. The basic shades are those of

brown. The darker the shade, the higher is the

height above sea level. The altitudes represented

by each tint are indicated on the maps and charts.

Sometimes referred to as elevation tint or layer

tint. Also called altitude tinting.

Spot Height: A spot height is an exact point on a

map with an elevation recorded beside it that

represents its height above a given datum.It‟s the

eleveation of certain point. Simply, it‟s a mark on

a map indicating the height of a hill, mountain,

etc.

Figure 3: Layer Tinting

Figure 4: Spot Height

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Bench Mark: A benchmark is a point of

reference by which something can be measured.

In surveying, a "bench mark" (two words) is a

post or other permanent mark established at a

known elevation that is used as the basis for

measuring the elevation of other topographical

points.

Trigonometrical Station: A triangulation

station, also known as a triangulation pillar,

trigonometrical station, trigonometrical point,

trig station, trig beacon, or trig point, and

sometimes informally as a trig, is a fixed

surveying station, used in geodetic surveying and

other surveying projects in its vicinity.

Fault Lines: Fault lines are some straight

lines shown in the map to indicate the fault

surface. It‟s often associated with the

topological and geological fetaures of a land

formt. It is a break or fracture in the ground

that occurs when the Earth's tectonic plates

move or shift and are areas where

earthquakes are likely to occur.

Gradient Analysis: Gradient analysis refers to the measurement and interpretation of the

gradients of a topographic map, including the methods to determine the gradients.

Gradient is a term to define the steepness of a slope regarding either the inclination or

declination.

Figure 5: Bench Mark

Figure 6: Trigonometrical Station

Figure 7: Major fault lines of the world

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Frontline: Front refers to the border zone between two contrasting air masses and

usually in temperature. Front lines are used to indicate the border zone in a

topographic map.

6. HOW TO DETERMINE A SLOPE: A To calculate the slope of a line you need only two points from that line, (x1, y1) and (x2, y2).

The equation used to calculate the slope from

two points is:

On a graph, this can be represented as:

𝑆𝑙𝑜𝑝𝑒 =(y2− y1)

(𝑥2− 𝑥1)

There are three steps in calculating the slope of a straight line when you are not given its

equation.

1. Step One: Identify two points on the line.

2. Step Two: Select one to be (x1, y1) and the other to be (x2, y2).

3. Step Three: Use the slope equation to calculate slope.

A moment should be taken to work through an example where we are given two points.

Example

Let's say that points (15, 8) and (10, 7) are on a straight line. What is the slope of this line?

1. Step One: Identify two points on the line.

In this example we are given two points, (15, 8) and (10, 7), on a straight line.

2. Step Two: Select one to be (x1, y1) and the other to be (x2, y2).

It doesn't matter which we choose, so let's take (15, 8) to be (x2, y2). Let's take the point (10, 7)

to be the point (x1, y1).

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3. Step Three: Use the equation to calculate slope.

Once we've completed step 2, we are ready to calculate the slope using the equation for a slope:

We said that it really doesn't matter which point we choose as (x1, y1) and which to be (x2, y2).

Let's show that this is true. Take the same two points (15, 8) and (10, 7), but this time we will

calculate the slope using (15, 8) as (x1, y1) and (10, 7) as the point (x2, y2). Then substitute these

into the equation for slope:

The same is found answer as before.

7. INTERPRETATION OF TOPOGRAPHIC MAP:

7.1: PROVIDED MAP The provided map is named as “BANGLADESH-INDIA; DINAJPUR, JAIPURHAT AND

RANGPUR DISTRICT, WEST BENGAL”. Supplied sample number 78 G/3. It shows the

Physical and Cultural futures of Dinajpur, Jaipurhat and Rangpur districts. It shows both the area

of Bangladesh and India.

7.2: PHYSICAL ANALYSIS OF THE SUPPLIED MAP The physical features are mentioned and analyzed below-

Terrain: The terrain of the supplied map is mostly flat. It contains agricultural

area, transport and cultural phenomena.

Elevation: The elevation points are very few. The area is almost a flat area with

forests and transportation. Much elevation points are not observed.

Depression: The depression points are not as few as elevation points but there

are not greater in number as well. There are few lakes, rivers and water bodies

that can be considered as depression area or points.

Mountains Valleys: The amount of mountain is closer to zero. No notable

mountains are observed in the map. Consequently, the amount of valleys is few

as well.

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Vegetation Coverage: There is a great area with vegetation coverage. There are

trees, forests, cultivation lands, trees, confines, shrubs, herbs, grass, cane,

bamboo in the map. The vegetation coverage is observed in every transportation

area and settlement area as well.

Hydrology: There are notable number of water bodies, marshes, ponds, rivers,

lakes etc. A branch of Teesta River has been flowing near Chota Padampur. It

has some canals and probable floodplains.

Valley and Floodplains: The river valley creates some notable floodplains in

the mapped area and valleys are not in greater numbers.

7.3: CULTURAL INFORMATION OF THE SUPPLIED MAP The cultural features are mentioned and analyzed below-

1. Settlement Pattern: The settlement patterns in the mapped area are of four

types-nuclear settlement, semi-nuclear settlement, scattered settlement and linear

settlement.

Nuclear settlement: Found in the area of the absence of

transportation or river or canals.

Semi-nuclear settlement: Found between the nuclear and linear

pattern of settlement.

Linear settlement: Found near railroads, roads, rivers and

canals.

Scattered settlement: The scattered settlement in the studied map

is without any pattern. The can be found dispersedly anywhere in

the map; probably because of the domination of the forest areas.

2. Transportation Network: In the studied map, there are 3 types of the

transportation. These are- railroads, roads and water transport.

Railroads: Railroads are found throughout the entire area of the

maps. Both national and international railroads are observed.

Railroads crossed international border area between Bangladesh

and India at the south western part of the map. Broad gauge, small

gauge, double gauge etc. are observed in different parts of the

area.

Roads: Roads are observed at the linkage of railroads. Many

areas where railroads don’t go, roads are the available transport

there, according to the map.

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Water Transport: Water transports are not greater in amount.

Some water routes are observed at the north western part of the

map along with the Teesta River.

3. Occupation: Occupation of the people can be assumed considering the natural

resources, cultural features and physical features of the map. Mainly they are

dependent on primary economic activities for livelihood. Their possible

occupations are given below.

Farming: Vast agricultural areas are available; consequently people are

dependent on agricultural activities such as farming, cultivating, crop

production, crop marketing etc.

Fishing: The existence of river and canals indicate that the inhabitants

rely on fishing and marketing of fisheries for livelihood.

Forest resources: People probably use the forest resources such as

fruits, woods, fire woods, forest farming (rudimentary sedentary tillage),

forest business etc.

Transportation workers: People probably work in the transportation

industries as there is a huge shape of transport network in the area.

Religious institutions: There are a number of mosques, churches and

temple in the studied map. People may get engaged in serving religious

sectors in order to earn livelihood.

Industrial workers: There are few tea gardens in the supplied map.

Probable existence of cash crop industries may influence the inhabitants

to get engaged in laboring work.

4. Agricultural process: Agricultural process of the studied area is probably

primitive as it‟s situated in mostly rural areas. Fallow land, ancient instrument,

uneven land distribution etc. are the major characteristics of the agriculture of the

studied area. A plurality of the mapped location earns their living from

agriculture. Although rice and jute are the primary crops, wheat is assuming

greater importance. Tea is grown in the northeast. Because of Bangladesh's

fertile soil and normally ample water supply, rice can be grown and harvested

three times a year in many areas.

7.4: ANALYSIS BETWEEN THE PHYSICAL AND CULTURAL RELATIONS OF THE

SUPPLIED MAP The physical and cultural relations are quite vivid from the determined assumptions and physical

feature of the studied map. Those are written below-

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i. The studied map area is almost flat; consequently it was possible to establish

such large network in the studied map.

ii. There availability of transport and rivers persuaded the settlement patterns to be

nuclear and linear in the appropriate locations.

iii. The balancing between roads and railroads were possible because of the flat

terrain and unavailability of mountain areas.

iv. Water transport was possible because of the presence of rivers and canals in the

mapped area.

v. The availability of agricultural area persuaded the inhabitants to earn livelihood

from farming and agriculture.

vi. The availability of fluvial area persuaded the inhabitants to earn livelihood from

fisheries.

vii. The availability of forest area persuaded the inhabitants to earn livelihood from

using and manufacturing forest resources.

viii. The availability of cash crops persuaded the inhabitants to earn livelihood from

cash crop industry.

ix. The flat area and dispersed settlement persuaded the inhabitants to establish

village centers and town centers.

x. The physical feature of the area influences the inhabitants to lead their life in

accordance with the terrain and climate.

7.5: PREDICTION AFTER 24 YEARS After 24 years, several phenomena can be changed. Some predictions are made on the base of

present condition and assumptions. Those are written below.

i. Prediction about terrain: Several more depression area can be created because of

the mature stage of the river and its continuous changing shape. But the elevation

points should be stable as there is no major fault line in the studied map.

ii. Prediction about hydrology: The river may invade the surface because of the

river bank erosion. The changing feature of the river may influence the banks to be

eroded and deposited inside of the river.

iii. Prediction about vegetation coverage: The vegetation coverage may decrease as

there are a trend of inhabitants to increase the settlement; and also because of

population explosion and urbanization.

iv. Prediction about floodplain: Like any other fluvial area, the floodplain area is

tending to increase and get shaped and may create oxbow lake as well.

v. Prediction about transportation: The number of road and railroads may increase

in the future because of the border transit and international transportations. But it is

unlikely to get decreases the road network considering the demand and necessities.

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vi. Prediction about occupation: People may move to secondary economic activity

rather than primary with the advancement of technology, economy and

industrialization in the both country (India and Bangladesh).

vii. Prediction about agriculture: The advancement in agricultural sector is possible

and it is very likely. Introduction of modern technology, modern machinery,

modern methods of farming, and modern knowledge of farming will probably be

observed within the next 24 years in the study area.

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SECTION-2:

GEOLOGIC MAP

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8. GEOLOGIC MAP AND ITS TYPES A geologic map or geological map is a special-purpose map made to show geological features.

Rock units or geologic strata are shown by color or symbols to indicate where they are exposed

at the surface. Bedding planes and structural features such as faults, folds, foliations, and

lineations are shown with strike and dip or trend and plunge symbols which give these features'

three-dimensional orientations.

Geological maps fall into four main groups. These are: reconnaissance maps; maps made of

regional geology; large-scale maps of limited areas; and maps made for special purposes. Small-

scale maps covering very large regions are usually compiled from information selected from one

or more of these groups.

1. Geological reconnaissance maps: Reconnaissance maps are made to find out as much as

possible about the geology of an area as quickly as possible. They are usually made at a

scale of 1:250 000 or smaller, sometimes very much smaller. Some reconnaissance maps

are made by photogeology, which is by interpreting geology from aerial photographs,

with only a minimum of work done on the ground to identify rock types and to identify

dubious structural features, such as lineaments. Reconnaissance maps have even been

made by plotting the main geological features from a light aircraft or helicopter with,

again; only brief confirmatory visits to the ground itself. Airborne methods are

particularly useful in regions where field seasons are short, such as in northern Canada

and Alaska.

2. Regional geological maps: Reconnaissance may have given the outline of rock

distribution and general structure; now the geology must be studied in more detail, most

commonly at a scale of 1:50 000 or 1:25 000, although any resulting map will probably

be published at 1:100 000.

Regional geological maps should be plotted on a reliable base. Unfortu-nately, in some

countries, geological mapping outstrips topographic coverage when there is a sudden

economic interest in a specific area and geologists must then survey the topography

themselves. An accurate geological map loses much of its point if superimposed on an

inadequate topographic base.

Regional geological mapping done on the ground may be supported by systematic

photogeology, and it should be emphasised that photogeological evidence is not inferior

to information obtained on the ground although it may differ in character. Some

geological features seen on aerial photographs cannot even be detected on the ground

while others can even be more conve-niently followed on photographs than in surface

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exposures (see Section 4.10). All geological mapping should incorporate any techniques

which can help in plotting the geology and which the budget will allow, including

geophysics, pitting, augering, drilling and even the use of satellite images where

available.

3. Detailed geological maps: Scales for detailed geological maps may be anything from

1:10 000 and larger. Such maps are made to investigate specific problems which have

arisen during smaller-scale mapping, or from discoveries made during mineral

exploration, or perhaps for the preliminary investigation of a dam site or for other engi-

neering projects. In Britain 1:10 000 is now the scale used for regional maps by the

Geological Survey to cover the whole country, replacing the older „6 inches to the mile‟

series (1:10 560). Few countries match this detail for their regional topographic and

geological map coverage. This is also the scale most commonly used by British students

for their own mapping projects.

4. Specialised maps: Specialised maps are many and various. They include large-scale

maps of small areas made to record specific geological features in great detail. Some are

for research, others for economic purposes, such as open pit mine plans at scales from

1:1000 to 1:2500; underground geological mine plans at 1:500 or larger; and engineering

site investigations at similar scales. There are many other types of map with geological

affiliations too. They include geophysical and geochemical maps; foliation and joint

maps; and sampling plans. Most are superimposed over an outline of the geology, or

drawn on transparencies to be superimposed on geological maps, to study their

relationship with the solid geology.

9. IMPORTANCE OF GEOLOGIC MAP: An accurate geologic map is needed to understand the Earth‟s resources and hazards. A geologic

map provides basic data for understanding both past and present-day processes affecting a region

of the Earth. This kind of information is important for four main reasons:

1. To provide geologic information that can help to reduce death and damage caused

by geologic hazards such as earthquakes and landslides. Different types of geologic

materials can amplify shaking or even liquefy during earthquakes. Some also are more

likely to produce landslides, or they may contain natural deposits of hazardous asbestos

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or mercury. A geologic map shows where these types of geologic materials are, as well as

the location of faults that might generate earthquakes.

2. To better find and protect or safely extract geologic resources. Concrete, sand,

metals, petroleum, even groundwater, are all important geologic resources, but to benefit

society, they first must be found. A geologic map shows the distribution of the rocks and

sediments that are most likely to contain these resources.

3. To improve our stewardship of the Earth through informed agriculture,

construction, and environmental practices. A geologic map shows the distribution of

the types of geologic materials that are likely to produce poor soils that are unsuitable for

agriculture (for example, map unit Jsp). It also shows which rocks will provide the safest

foundations for buildings and roads, as well as those which can help support important or

endangered species.

4. To help geologists unravel the geologic history of the region. The relations between

the geologic materials and structures shown on the geologic map give clues about the

sequence of events that happened in the area in the past. An improved understanding of

the geologic history helps us to better understand the region's geologic resources and

hazards.

10. USES OF GEOLOGIC MAPS: Geologic map can be applied to assist the following phenomena-

Rock Descriptions

Identifying and Naming Rocks in the Field

Litho-stratigraphy and Sedimentary Rocks

Fossils Determination

Phaneritic Igneous Rocks Determination

Aphanitic Igneous Rocks Determination

Veins and Pegmatites Determination

Igneous Rocks Determination in General

Pyroclastic Rocks Determination

Metamorphic Rocks Determination

Interpretation of Economic Geology Aspects

Distribution of Geological Features

Land Planning

Construction Activities etc.

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Map 1: Geologic map of Bangladesh

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11. STAGES TO FORM A GEOLOGIC MAP: The main equipment needed to do geological mapping is:

1. Base Map: is used to show an overview of the area that will be mapped.

2. Compass and Clinometer: is used to measure the strike and dip from a rocks and

geological structure.

3. Stationery and field notebook: is used to record and describe the characteristic of

rocks was found at the observation location.

4. Hammers and Chisels: is used to take rocks samples.

5. Hand lens: is used to observe the characteristics of rock that cannot be seen with the

eye directly, such as the grain size and others

6. Gauge: is used is used to determine the length of an outcrop or structure.

7. GPS: is used to determine the outcrop location.

The steps to do geological mapping activity are:

1. We make outcrop observation, and make a description of it.

2. We measure the position of rocks (strike and dip), geological structure elements, and

other geological elements.

3. We make a record observations in a field notebook

4. We determine the outcrop location by using GPS.

STEPS TO CREATE GEOLOGICAL MAPS:

1. Make Geological Maps Framework

Geological maps framework is a set of data that is used to the process of makinga map. The

contents is:, symbols of station number (track); types of rock symbol; Plotting symbol of

strike/dip; Plotting symbol of structure element.

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Figure 8: Lithology of Outcrop and Field Structure Sketch.

2. Make a Strike and Dip Map

This map shows the plots of strike and dipfrom a region. In the reconstruction, it necessary some

step:

Inventory a required data, such as strike and dip, and the description ofrockintorock

unitsalong withits contacts as well asan indication ofthe geologicalstructures(faults,

folding)

Plotting data on the map. We make a contour map based on the similarity towards the

strike and dips of outcrops were obtained.

Figure 9: Strike/Dip Data Plot and Indication of Geology Structure.

How to reconstruct the pattern of strike of the rock layering pattern is as follows: plot the

data needed; create key strike/dip contour; reconstructs the geological structure if any;

and reconstructs the pattern of strike and dip.

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Figure 10: Data Plot on 25°

3. Make Geological Map

Some things that need to be considered in making geological maps is: determining the spread of

the unit and formation. restrict the lithology in accordance with the lithology contacts on the

strike and dip map. Also draw the location of geological structures in accordance with the

boundary of the strike and dip map. Give lithology colour in accordance with the standards

colour and provide explanation too. And the last, make the cross section from its map.

Cross Section

Geological maps can not be considered complete until there is at least one cross section has been

created to show the geology below the surface. Cross section describes the structure of a region

that is much clearer than a planimetris map.cross section can be drawn in addition to a map of

the fair copy,and simplified again as an illustration in a cross section of the report.it can show

geological formation boundary at depth,and can also be used to display a fault, cleavage and

surface folds on the map.

Measures to make a Cross section:

1. Draw the line section (A-B) on face of the map.

2. Fasten the map to the drawing board or table with the line Section in parallel on the lower

edges of the drawing board or table,

3. Tape part map, a few centimeters below the line section, then the line of paper to do the

plot lines of the section.

4. Basic line drawings on paper are parallel to the lines of the section of the map. Then pull

a series of parallel lines on a contour intervals selected Above. The distance of these lines

should be aligned with the vertical scale contour maps.

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5. Press the plastic ruler or a straight steel edge on paper until it cannot move, so that the

paper remains parallel to the base line.

6. By shifting the point of elevation along the edges, and drop a perpendicular down to the

appropriate height on the paper section of every point where this part is cutting the

contour lines on a map. Follow these points to give a profile of topography.

Figure 11: How to Make Cross Section

12. DEFINITION OF IMPORTANT GEOLOGIC TERMS: Bearing: Bearing refers to direction, especially angular direction measured from one

position to another using geographical or celestial reference lines.

Unconformity: An unconformity is a buried erosional or non-depositional surface

separating two rock masses or strata of different ages, indicating that sediment

deposition was not continuous. In general, the older layer was exposed to erosion for

an interval of time before deposition of the someonenger, but the term is used to

describe any break in the sedimentary geologic record.

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Figure 12: Hutton Unconformity

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Faulting: A faulting or fault is a planar

fracture or discontinuity in a volume of rock,

across which there has been significant

displacement as a result of rock-mass

movement. Large faults within the Earth's

crust result from the action of plate tectonic

forces, with the largest forming the

boundaries between the plates, such as

subduction zones or transform faults. Energy

release associated with rapid movement on

active faults is the cause of most earthquakes.

Strike: Strike is associated with dip. Dip

is the acute angle that a rock surface

makes with a horizontal plane. Strike is

the direction of the line formed by the

intersection of a rock surface with a

horizontal plane. Strike and dip are

always perpendicular to each other on a

map.

Line match: Line match refers to matching up, repairing, correcting and merging of

lines in a geologic map. A line is a straight one-dimensional figure in a geologic map

having no thickness and extending infinitely in both directions.

Figure 13: A Faulting in Morocco

Figure 14: Strike

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SECTION-3:

WEATHER MAP

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13. WEATHER MAP A weather map displays various meteorological features across a particular area at a particular

point in time and has various symbols which all have specific meanings. Such maps have been in

use since the mid-19th century and are used for research and weather forecasting purposes. Maps

using isotherms show temperature gradients, which can help locate weather fronts. Isotach maps,

analyzing lines of equal wind speed, on a constant pressure surface of 300 or 250 hPa show

where the jet stream is located. Use of constant pressure charts at the 700 and 500 hPa level can

indicate tropical cyclone motion. Two-dimensional streamlines based on wind speeds at various

levels show areas of convergence and divergence in the wind field, which are helpful in

determining the location of features within the wind pattern. A popular type of surface weather

map is the surface weather analysis, which plots isobars to depict areas of high pressure and low

pressure. Cloud codes are translated into symbols and plotted on these maps along with other

meteorological data that are included in synoptic reports sent by professionally trained observers.

Map 2: Current Weather map of Bangladesh

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14. SIGN AND SYMBOL OF A WEATHER MAP: There are several signs and symbols of a weather map. They have been discussed below.

TIME SYMBOL:

Figure 15: Time symbol

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HIGH AND LOW AIR PRESSURE CENTERS

Figure 16: High and Low Pressure Centre

Blue H's and red L's on weather maps indicate high and low pressure centers. They mark where

the air pressure is highest and lowest relative to the surrounding air and are often labeled with a

three- or four-digit pressure reading.

Highs tend to bring clearing and stable weather, whereas lows encourage clouds and

precipitation; so pressure centers are sort of "x-marks-the-spot" areas for determining where

these two general conditions will occur.

Pressure centers are always marked on surface weather maps. They can also appear on upper air

maps

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ISOBARS

Figure 17: Isobar

On some weather maps somone may notice lines surrounding and encircling the "highs" and

"lows." These lines are called isobars because they connect areas where the air pressure is the

same ("iso-" meaning equal and "-bar" meaning pressure). The more closely the isobars are

spaced together, the stronger the pressure change (pressure gradient) is over a distance. On the

other hand, widely-spaced isobars indicate a more gradual change in pressure.

Isobars are found only on surface weather maps -- although not every surface map. Be careful

not to mistake isobars for the many other lines that can appear on weather maps, like isotherms

(lines of equal temperature)!

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WEATHER FRONTS AND FEATURES

Figure 18: Weather Fronts and Features

Weather fronts appear as different colored lines that extend outward from the pressure center.

They mark the boundary where two opposite air masses meet.

Warm fronts are red curved lines with red semi-circles.

Cold fronts are blue curved lines with blue triangles.

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Stationary fronts have alternating sections of red curves with semi-circles and blue

curves with triangles.

Occluded fronts are purple curved lines with both semicircles and triangles.

Weather fronts are found ONLY on surface weather maps.

SURFACE WEATHER STATION PLOTS

Figure 19: Weather Station Plot

As seen here, some surface weather maps include groupings of numbers and symbols known as

weather station plots. Station plots describe the weather at a station location, including reports of

that location's...

air temperature (degrees Fahrenheit),

dewpoint temperature (degrees Fahrenheit),

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current weather,

sky cover,

atmospheric pressure (in millibars),

pressure tendency, and

wind direction and speed (in knots).

If a weather map has already been analyzed, someone'll find little use for the station plot data.

But if someone'll be analyzing a weather map by hand, station plot data is often the only

information someone start off with. Having all stations plotted on a map guides someone as to

where high and low pressure systems, fronts, and the like are located which ultimately helps

someone decide where to draw them in.

WEATHER MAP SYMBOLS FOR CURRENT WEATHER

Figure 20: Weather Map Symbols for Current Weather

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These symbols are used in weather station plots. They tell what weather conditions are currently

happening at that particular station location.

It is only plotted if some type of precipitation is occurring or some weather event is causing

reduced visibility at the time of observation.

SKY COVER SYMBOLS

Figure 21: Sky Cover Symbols

Sky cover symbols are used in station weather plots. The amount that the circle is filled

represents the amount of sky that's covered with clouds.

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The terminology used to describe cloud coverage -- few, scattered, broken, overcast -- are also

used in weather forecasts.

WEATHER MAP SYMBOLS FOR CLOUDS

Figure 22: Weather Map Symbols for Clouds

Each cloud symbol is labeled with an H, M, or L for the level (high, middle, or low) where it

lives in the atmosphere. The numbers 1-9 tell the priority of the cloud reported; since there's only

room to plot one cloud per level, if more than one cloud type is seen, only the cloud with the

highest number priority (9 being highest) is plotted.

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WIND DIRECTION AND WIND SPEED SYMBOLS

Figure 23: Wind Direction and Wind Speed Symbols

Wind direction is indicated by the line that extends out from the station plot sky cover circle.

The direction the line points is the direction that the wind is blowing from.

Wind speed is indicated by the shorter lines, called "barbs," which extend from this longer line.

The total wind speed is determined by adding together the different sizes of barbs according to

the following winds speeds that each represents:

Half barb = 5 knots

Long barb = 10 knots

Pennant (flag) = 50 knots

Wind speed is measured in knots and is always rounded to the nearest 5 knots.

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PRECIPITATION AREAS AND SYMBOLS

Figure 24: Precipitation Areas and Symbols

Some surface maps include a radar image overlay (called radar composite) that depicts

where precipitation is falling based on returns from weather radar. The intensity of rain, snow,

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sleet, or hail is estimated based on color, where light blue represents light rain (or snow) and

red/magenta indicates flooding rains and/or severe storms.

WEATHER WATCH BOX COLORS

If precipitation is severe, watch boxes will also show up in addition to precipitation intensity.

Red dashed = tornado watch

Red solid = tornado warning

Yellow dashed = severe thunderstorm watch

Yellow solid = severe thunderstorm warning

Green = flash flood warning

15. DIFFERENCE BETWEEN WEATHER AND CLIMATE: Weather is the day-to-day state of the atmosphere in a region and its short-term (minutes to

weeks) variations, whereas climate is defined as statistical weather information that describes the

variation of weather at a given place for a specified interval. They are both used interchangeably

sometimes but differ in terms of the length of time they measure and what trends affect them.

Weather is the combination of temperature, humidity, precipitation, cloudiness, visibility, and

wind. In popular usage, climate represents the synthesis of weather; more formally, it is the

weather of a locality averaged over some period (usually 30 years), plus statistics of weather

extremes.

Although they have similarities, but the both phenomena are different from each other in many

ways. The keys differences between weather and climate are shown below.

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Topic Weather Climate

Definition Weather is the state of the

atmosphere on a current day at a

current time. It changes day to day.

Climate is the average

conditions that are expected

at a certain place over a

number of years.

Components Weather includes sunshine, rain,

cloud cover, winds, hail, snow,

sleet, freezing rain, flooding,

blizzards, ice storms,

thunderstorms, steady rains from a

cold front or warm front, excessive

heat, heat waves and more.

Climate may include

precipitation, temperature,

humidity, sunshine, and

wind velocity, phenomena

such as fog, frost, and hail

storms over a long period

of time.

Forecast Day to day forecast can be done

depending on the air pressure,

temperature and other similar

factors.

Climate forecast can only

be done over longer periods

of time, such as 30 years.

The average of weather

over 30 years helps

determine the climate of a

certain area.

Determined by Real-time measurements of

atmospheric pressure, temperature,

wind speed and direction,

humidity, precipitation, could

cover, etc.

Aggregating weather

statistics over periods of 30

years

Study Meteorology Climatology

Table-1: Difference between Weather and Climate

16. CONCLUSION: The topographic, geologic and weather map all are essential for comprehending map study and

cartography. The understanding of weather symbol is essential for explaining weather map.

Altogether, it‟s essential to study each of them elaborately and vividly.