1. Presentation on geology & Geological timescale of Bangladesh
GROUP -C
PRESENTED BY:
ROLL- 875, 884, 892, 905, 917, 1856
COURSE NO- 301

2. QUESTIONS What are geology & geology 0f BD?
What is Geological Time Scale ? Show the Time Scale of BD with map?
What Are Geological Formations?
Show the Geological Group Formation of BD.
Why Geology & Geological Time Scale are so important in Geography?

3. Preface
Geological evolution of Bangladesh is basically related to the uplift of the Himalayan Mountains and outbuilding of deltaic landmass by major river systems originating in the uplifted himalayas. This geology is mostly characterized by the rapid subsidence and filling of a basin in which a huge thickness of deltaic sediments were deposited as a mega-delta out built and progressed towards the south.
The delta building is still continuing into the present bay of bengal and a broad fluvial front of the Ganges-Brahmaputra-Meghna river system gradually follows it from behind. Only the eastern part of Bangladesh has been uplifted into hilly landform incorporating itself into the frontal belt of the indo-burman range lying to the east. All the above has been the result of the Indian plate colliding with the Asian plate as explained by the universally accepted theory of plate tectonics.

4. 1.What is geology & geology 0f BD?
Geology is the study of the Earth, the materials of which it is made, the structure of those materials, and the processes acting upon them. It includes the study of organisms that have inhabited our planet. An important part of geology is the study of how Earth’s materials, structures, processes and organisms have changed over time.
Geology is The study of the planet Earth & the materials of which it is made, the processes that act on these materials, the products formed, and the history of the planet and its life forms since its origin.

5. Geology of Bangladesh Bangladesh occupies the delta plain of the Ganges (Padma) and the Brahmaputra (Jamuna) rivers. The country’s geological history is covered by several kilometers of 2-million-year-old sediments.

6. 2. What is Geological Time Scale ? Show the Time Scale of BD with map?
The geologic time scale provides a system of chronologic measurement relating stratigraphy to time that is used by geologists, paleontologists and other earth scientists to describe the timing and relationships between events that have occurred during the history of the Earth.
The geological time scale divides the total time span of earth's 4.6 billion years of existence into units and sub-units on the basis of rock records. It basically includes four eras, such as,
01. Precambrian Era
02. Paleozoic Era
03. Mesozoic Era
04. Cenozoic Era
Insert a picture of one of the geographic features of your country.
These eras are subdivided into periods and the periods into epochs.

7. Geological timescale of Bangladesh
The Geological evolution of Bangladesh is shown by time scale
(source –Banglapedia)

8. Geological timescale of Bangladesh
Insert a picture of an animal and or plant found in your country.
Source: Himalayan Research Laboratory.
Auburn University; Alabama; USA.

9. In Geological Time Scale
ERA
PERIOD
EPOCH
GROUP
FORMATION C E N O Z I
QUATERNARY
Holocene
Pleistocene
Pliocene
Late Miocene
Middle Miocene
Lower Miocene
Oligocene
Late Eocene
Middle Eocene
Early Eocene
Lower –Cretaceous
Late Jurassic
Late Permian
Early Permian
Alluvium
Madhupur Clay
St. Martin’s
Limestone T R A Y G
Dihing
Dupitila-Claystone
Dupitila-Sandstone P L
Tipam
Girujan Clay
Tipam Sand Stone
Surma
Barail
Renji?
Jenum?
Jaintia
Kopili Shale
Sylhet Limestone
Tura Sandstone
MESOZOIC
CRETACEOUS
JURASSIC
PERMIAN
Rajmahal
Sibganj
PALEOZOIC
Gondwana
Raniganj
PRECAMBRIAN
Insert a picture illustrating a season in your country.
Source: Geology of Bangladesh, By F. H. Khan. P:33

10. 3. What Is Geological Formations?
Geological formations are groupings of rock with similar characteristics. In geology, the term refers specifically to geological strata, while laypeople may refer informally to outcroppings of rock or interesting geological features as geological formations, even though this is not technically correct.
Visualizing geological formations is easiest to do when one things about the landscape in cross section. If a hillside is sliced in two, layers of geological material will appear. When materials in a layer are of similar age or composition, they can be termed a geological formation. Geological formations can be bundled together in large groups, or broken down into smaller segments called members, to help geologists describe, explore, and study them. When a geologist finds a formation which he or she thinks is new, the information is presented to the authority which handles naming conventions in the area, and if the formation is verified as a new discovery, the geologist may have the honor of naming it.

11. Many geological formations are made from sedimentary rock, although other types of rock can also be found in a formation. The type of rock can be important, as it may provide information about the conditions in which the rock formed, and the geologic history of an area. Multiple deposits of limestone formations, for example, indicate that an area was once covered in an ocean, while a layer of volcanic flow would suggest that there was volcanic activity in the region at some point in history.
Identifying, describing, and naming geological formations is part of stratigraphy the study of layers of rock in geology. Geologists can prepare maps showing various formations in an area and their relationship to each other, and they can use these maps to learn about geologic history. Sometimes events may be more readily apparent when a map is examined than when people are out in the field, because the map distills the information in the landscape into small chunks of useful information.

12. 4. Show the Geological Group Formation of BD?
Firstly: “Alluvium, Stream deposits” Delta plan deposit, FLood plain deposits.
Secondly: “Pleistocene terrace” (Madhupur clay)
Thirdly: “Pleistocene, Dupi Tila formation”
Fourthly: “Pleistocene Tipan sand stone formation” Girujan clay formation
Fifthly: “Miocene, Surma group”.
Sixthly: Paleogene (Sylhet lime stone, Renji formation).
Seventh: Lower Miocene - Pleistocene

13. FIRSTLY: “Alluvium, stream Deposits” is the largest geological group formation. Except Chittagong and Madhupur track some all are this types. Maximum parts of Bangladesh are formed with alluvium, stream deposits. That is also called plain land. This region is differ from any other region of the world.
Source: Banglapedia

14. SECONDLY: “Pleistocene Terrace”(Madhupur clay) this regions are placed in Dhaka, Gazipur and Moymensingh. This region is called Madhupur and Vawal tract.
Madhupur clay:
The Madhupur clay was earlier called the ‘old alluvium’ and was regarded as Pleistocene is age. The madhupur clay is reddish brown in colour, oxidised, sticky and rather compact. The Madhupur & Barind Tracts, which together occupy about 8% of the country, are underlain by the Madhupur clay.
Source: Banglapedia

15. THIRDLY: “Pleistocene, Dupi Tila formation” It is found normally in the hilly area of sylhet and chittagong. it is composition of some hillock.
Source: Banglapedia

16. FOURTHLY: “Pleistocene Tipan Sand Stone Formation” this types of region is marked as high land. Composition of high area of the hill is under this condition. It is found highly in Chittagong, Khagrachari & Bandarban.
Source: Banglapedia

17. Fifthly: “Miocene, Surma group” Geologist belive that this region is very old. It also assume that it is the result of Plate Techtonic. This region is very high and formed with many hillocks. But it is found the presence of plain land.
Source: Banglapedia

18. Sixthly: “Paleocene” (Sylhet Limestone, Renji Formation) mainly this types of region is very little in Bangladesh. A small area of Sylhet district it is found the presence of it.
Source: Banglapedia

19. Seventhly: “Paleocene” mainly this types of region is very little in Bangladesh. A small area of Sylhet district it is found the presence of it.
MAXIMUM PARTS OF BANGLADESH ARE FORMED WITH ALLUVIUM, STREAM DEPOSITS. THAT IS ALSO CALLED PLAIN LAND. THIS REGION IS DIFFER FROM ANY OTHER REGION OF THE WORLD.
Source: Banglapedia

20. 5. Why Geology & Geological Time Scale is so important in Geography?
The science of Geology is significant in locating water supplies, mineral resources, understanding the development of life on earth, developing predictive models for earthquake, volcano and tsunami activity and adding fundamental knowledge to the field of earth and planetary science. Geology is important in determining building placement, discovery of resources such as gravel , stone , oil , coal, water and mineral deposit, knowledge of rock and mineral properties, landslide avoidance , erosion control, determining planetary histories, and earthquake and volcano eruption prediction.

21. Geography deals with time, space, environment and human beings
Geography deals with time, space, environment and human beings.Geological Time scale tells a vast history in short of these.
Suppose, if we want to identify the formation of rocks or emerged the life evidence or plants, then Geological time scale must be required. Beside this, to know the origin of the earth, different age of environment we need this.

22. CONCLUSION
Geological structure is very important for development of any region. The economical, social, political and cultural progress of a country depends on its Geological structure. For the development of Bangladesh we have to acquire proper knowledge about geology and geological history of Bangladesh. In contrast we can say that bengal basin originally formed from gondowana.

23. THANKS TO ALL……