Nile Univ. geology project group 1a.pptx

Nile Univeristy

1. geology project 1

2. PGE 302: PETROLEUM GEOLOGY 2

3. Group 1 Group leader: Iniobong Obot – 201205013 Mohammed Munzali – 20222648 Okopido Akeminiabasi – 201205044 Gana Ummi Baba – 201205032 Osasu Fountain Enoma – 201205010 Salisu Muhammed – 201205028 Jibrin Halima Sadiya – 201205050 Aisha Abubakar Wali – 201205043 Mahmud Ali Bukar - 201205051 3

4. General petroleum geology and hydrocarbons 4

5. INTRODUCTION 5

6. THE PETROLEUM SYSTEM A petroleum system is defined as the geological elements and procedures required for the production and storage of hydrocarbons. The production, accumulation, and storage of natural gas, petroleum, and other hydrocarbons are also supported by all the geological processes and constituents that make up the subsurface. The petroleum system is mapped using the fundamental ideas of petroleum geology and geochemistry in order to locate untapped natural gas and petroleum resources. 6

7. THE GEOLOGIC PRINCIPLES AND GEOLOGIC TIME SCALE 7

8. GEOLOGIC PRINCIPLES The Law of Superposition : This states that beds of rock on top are usually younger than those deposited below. By understanding the Law of Superposition generalized statements can be made about the ages of these rock units. The Law of Original Horizontality : This suggests that all rock layers are originally laid down (deposited) horizontally and can later be deformed. As a result, we may deduce that the rocks' tilting was caused by some event. Included in this are earthquakes, faulting, and mountain-building activities. 8

9. Geologic principles Cross-cutting relationships: The law or principle of cross-cutting relationships states that any geologic feature or rock unit that cuts or deforms another is younger than the rock body or geologic feature/structure it cuts or deforms. Walters law: Walther's law addresses relative space over time in addition to relative time, not only relative time. Walther’s law states that depositional environments that are laterally adjacent on the surface of the earth will also appear in succession in a stratigraphic sequence. 9

10. Geologic Time Scale In topography, the term "calendar" refers to the geologic time scale. Each period of time may be recognized and depicted by the event of critical geologic occasions and the appearance of critical life shapes, beginning with the creation of the Earth's crust and proceeding with the appearance of ever- changing forms of life on earth. The need to coordinate global geological events and order vast amounts of geological time has led to the development of geological time scales. 10

11. ROCKS AND MINERALS, ROCK CYCLE, RESERVOIR PROPERTIES 11

12. Rocks 12

13. T ypes of rocks I gneous rocks M etamorphic rocks S edimentary rocks Note: In the petroleum industry our main focus is on sedimentary rocks. 13

14. Classification OF SEDIMENTARY Rocks 14

15. Clastic Rocks They are made up of parts or grains of pre-existing rocks that have been eroded, transported and deposited. The texture of these rocks depends on the size of the sediment grains. Examples are sandstones which are coarse-grained, shales which are fine-grained, and conglomerates which are composed of rounded gravel-sized particles. 15 This Photo by Unknown Author is licensed under CC BY

16. Organic Rocks 16

17. Chemical Rocks 17

18. Key Characteristics of Sediments and Sedimentary Rocks 18

19. Rock Cycle Metamorphic rocks are formed from the cooling and solidification of molten magma. These rocks might then undergo weathering and erosion to form sediments. These sediments will be transported and deposited. They will then undergo compaction to form sedimentary rocks. 19

20. Rock cycle 20

21. HYDROCARBONS Hydrocarbons are organic compounds that are composed exclusively of atoms of hydrogen and carbon. They are the primary constituents of fossil fuels such as natural gas, oil and coal. Depending on their molecular structure and the kind of chemical bonds present between carbon atoms, hydrocarbons are classified into various categories. 21

22. Hydrocarbons These categories of hydrocarbons include saturated, unsaturated, aromatic, aliphatic, and alicyclic hydrocarbons. The chemical structure of hydrocarbon also determines their physical properties, such as boiling point and melting point. Their end products serve many users in different sectors such as residential, commercial, transportation, electric power and the industrial sector. 22

23. SOLID, LIQUID AND GASEOUS HYDROCARBONS 23

24. FORMATION AND OCCURRENCE OF HYDROCARBONS 24

25. HYDROCARBON ACCUMULATION 25

26. PETROLEUM EXPLORATION: GEOPHYSICAL APPLICATIONS IN PETROLEUM GEOLOGY Before discussing geophysical applications in petroleum geology, there is need for us to understand what geophysics entails so as to guide us to the understanding of geophysical applications in the field of petroleum geology. 26

27. What is geophysics? Geophysics in simple terms is the measurement of physical properties at or above the ground surface to reveal hidden subsurface structures. 27

28. Physical properties Density Magnetism Electrical conductivity Natural radioactivity Heat capacity 28

29. GEOPHYSICAL METHODS Seismic methods E lectrical resistivity methods E lectromagnetic methods M agnetic methods Gravity methods 29

30. Applications of seismic method 30 Exploration: Geophysicists record the bounced back seismic waves to learn about oil and gas reservoirs located beneath Earth’s surface. Fault Detection: Petroleum geologists can locate fault systems and ascertain their orientation, displacement, and sealing ability by examining seismic reflection data. Understanding reservoir compartmentalization and maximizing well placement depends on fault mapping. Imaging of Unconventional Reservoirs: Unconventional reserves can now be imaged with the help of seismic techniques. Because of their relatively low permeability, these reservoirs need hydraulic fracturing to be produced.

31. Applications of electrical resistivity method 31 Hydrocarbon Detection: The resistivity of hydrocarbons, such as oil and gas, is often higher than that of rocks containing water. Water-flood monitoring: To improve oil recovery, a reservoir may be "flooded" with water. Geologists can track the flow of the injected water and track how well it is displacing oil in the reservoir by tracking variations in resistivity over time. Fluid differentiation: Electrical conductivity varies with rock type and fluid content. Differences between various lithologies can be determined as well as the presence of hydrocarbons, water, or other fluids by measuring the resistivity of the subsurface using electrical probes or well logging instruments.

32. applications of electromagnetic methods 32 Environmental Monitoring: When evaluating probable environmental effects of petroleum operations, such as the movement of contaminants or leaks from storage facilities or pipelines, EM approaches are used. Detection of fractures: The identification and characterisation of subsurface fractures can be aided by EM surveys. In contrast to the underlying rock matrix, fractures frequently display divergent electrical characteristics. Fluid monitoring: The movement and variations in fluid saturation within a reservoir can be tracked over time using EM methods.

33. applications of magnetic method 33 Detecting Hydrocarbon: Due to the lack of magnetic minerals and the presence of hydrocarbons, hydrocarbon-bearing formations frequently exhibit low magnetic susceptibility in comparison to the rocks around them. Delineation of Intrusive Bodies: The distribution of hydrocarbons in a reservoir can be impacted by intrusive bodies such as igneous rocks and sills. Because these invasive bodies frequently display distinctive magnetic signatures, magnetic surveys can be useful in locating and defining them. Reservoir Characterization: Magnetic measurements can be used to locate fluid contacts and differentiate between various fluid types (such as water, oil, and gas) based on their magnetic responses.

34. applications of gravity method Structural Mapping: Gravity data can offer important information about the subsurface structure of a location. Locating Salt Domes: Important geological formations known as salt domes can act as hydrocarbon traps. Density Estimation: The changes in density within rock formations can be estimated using gravity methods. 34

35. conclusion The field of general petroleum geology and hydrocarbons is a vital discipline with significant implications for our energy security, environment stewardship, and scientific understanding of the earth. Understanding petroleum geology allows us to identify potential oil and gas fields and make informed decisions about their development and utilization. 35

36. 36 THANK YOU