MASA GEOLOGI

1. MASA GEOLOGI

2. FIELD & LAB WHERE KEGUNAAN MASA GEOLOGI WHY STUDY PETA GEOLOGI ASAS KAJIAN SKALA KAJIAN TAPAK MASA NISBI MASA MUTLAK KAEDAH TAKRIF

3. AGE OF THE EARTH Ancient rocks exceeding 3.5 billion years in age are found on all of Earth's continents. The oldest rocks on Earth found so far are the Acasta Gneisses in northwestern Canada near Great Slave Lake (4.03 Ga) and the Isua Supracrustal rocks in West Greenland (3.7 to 3.8 Ga), but well-studied rocks nearly as old are also found in the Minnesota River Valley and northern Michigan (3.5-3.7 billion years), in Swaziland (3.4-3.5 billion years), and in Western Australia (3.4-3.6 billion years).

4. Age of the universe The age of 4.54 billion years found for the Solar System and Earth is consistent with current calculations of 11 to 13 billion years for the age of the Milky Way Galaxy (based on the stage of evolution of globular cluster stars) and the age of 10 to 15 billion years for the age of the Universe (based on the recession of distant galaxies).

5. Konsep masa Dulu kini masa depan Past present future TUA MUDA LAMA BARU

6. Konsep masa: Dari sudut pandangan • Ahli sains masa lampau • Ahli sains masa kini • Ahli geologi/kajibumi masa lampau • Ahli geologi/kajibumi masa kini • Ahli sains Muslim? • Jurutera?

8. Uniformitarianism/Teori Keseragaman Limits of the Human Imagination

9. Uniformitarianism/Teori Keseragaman • The present is the key to the past Maksud: Apa jua proses geologi yg berlaku pada hari ini juga berlaku di masa yg lepas/lampau Contoh: luluhawa, ledakan gunung berapi, gempa bumi, hakisan, pengangkutan, pemendapan, dll

10. Revolution Number One Observation as a Source of Knowledge • Principle of Original Horizontality • Principle of Superposition

11. Masa geologi • Panjang & pendek • Cuba memahami proses kejadian alam (fauna, flora, manusia sebagai makhluk istimewa) • Cuba memahami produk (kejadian mineral & batuan, logam/bukan logam) untuk manafaat dunia sejagat • Cuba memahami persekitaran untuk kegunaan manusia • Bagi jurutera memahami ragam produk dan persekitaran (perubahan yang akan berlaku yg mungkin boleh mengubah struktur rekaan mereka)

12. Kitar batuan Mana dia proses? Produk?

13. SEDIAKALA/ BERUBAH/ DIUBAH ENVIROMEN PROSES PRODUK Peranan jurutera? Mampukah mereka memahami ragam persekitaran yang berubah/diubah?

14. Kepentingan masa geologi • Kajian proses dan produk • Kajian persekitaran asal ke baru • Kajian ragam proses-produk-persekitaran KAJIAN TAPAK (SITE INVESTIGATION)

15. KAJIAN TAPAK (SITE INVESTIGATION) • Memerlukan penggunaan Peta Geologi dan Peta Topo => surface dan subsurface geologi • Peta: merakamkan taburan batuan dan sedimen, persekitaran, rupa bentuk bumi, air, aktiviti ekonomi (kuari, perlombongan, pertanian, dll) • Kegunaan peta: pelbagai (ketenteraan, keselamatan, persekitaran tabii, ecotourism,dll)

16. Sebagai ahli sains asas, sains gunaan atau jurutera, kita mesti menghargai maklumat dan sumbangan yg dibuat demi kepentingan bersama • Jurutera mengolah enviromen tabii kepada yg baru • Perubahan yg dibuat menuntut kita ….

17. Jurutera mesti berupaya membaca peta dan mentafsir (dari descriptive ke interpretive science) The progress Of science Observation Hypothesis Prediction Decision Falsification Confirmation Observation

18. Masa Geologi: nisbi (relative) Tujuan: Order events from oldest to youngest (meletak sesuatu peristiwa yang berlaku mengikut tertib dari tua ke muda) • Principle of superposition • Principle of original horizontality • Principle of lateral continuity • Principle of cross-cutting relationship • Principle of inclusions • Principle of faunal succession

19. Masa Geologi: mutlak (absolute) 1 Methods relying on event in the geological record with strong annual cyclicity • Tree growth rings • Coral growth cycles • Varves (annual clay sediment layers) 2 Decay of radiogenic isotopes (using concept of half-life)

20. 1 Principle of superposition (Prinsip supertindanan) • States that in an undisturbed stack of sedimentary strata the oldest layer is at the base and the youngest at the top youngest C B A oldest

21. 2 Principle of original horizontality (Prinsip pendataran asal) • States that sedimentary strata were deposited in nearly horizontal layers • If flay lying layers are observed to be folded in a complex fashion, then folding must have followed the deposition of the layers

22. Sedimentary rocks formed as flat strata (Principle of original horizontality)

25. strata

26. 3 Principle of lateral continuity (Prinsip keselanjaran sisi) • States that sediments extends laterally until it thins or pinches out against the margin of the basin in which it is accumulating • Uninterrupted exposures – rare to find => necessary to correlate from one exposure to the next to determine how extensive some of these units really are

27. Enviroment of sedimentary rx

28. Principle of cross-cutting relationships (Prinsip hubung silang) • States that if unit or event A cuts across unit or event B, then A is younger than B

29. Principle of cross-cutting relationships

30. Masa nisbi Susun lapisan dari paling tua ke paling muda

31. Tugasan: masa nisbi Susun lapisan dari paling tua ke paling muda

32. Tugasan: Masa nisbi Susun lapisan dari paling tua ke paling muda

33. Adakah sill ini lebih tua/muda dari batuan dikelilingnya?

34. 5 Principle of inclusions • States that inclusions of rock A in rock B must be older than rock B

35. 6 Principle of faunal succession (Prinsip jujukan fauna) • states that fossil assemblages succeed one another through time in a regular and predictable order.

36. Index fossils

37. correlation

38. Correlation: stratigraphy

39. Unconformities (Ketakselarasan) • In a stack of sedimentary layers, some of them are missing through natural process (such as weathering and erosion) across a boundary. These breaks are called unconformities (ketakselarasan)

40. unconformities refers to the surface between two layers that were not laid down in an unbroken sequence

41. Types of unconformites • Disconformity • Angular unconformity • Nonconformity

42. A disconformity is an unconformity in which the upper set of strata (the younger set) overlies an erosional surface developed on undeformed (horizontal) lower (older) beds. These can be difficult to detect in the field unless there is a change in sedimentary facies between the upper and lower beds

43. An angular unconformity occurs when younger beds are deposited on strata that have been folded and eroded to produce a flat depositional surface. This implies deposition, followed by tectonism, erosion and further deposition.

44. A nonconformity is an unconformity in which the upper beds (younger beds) overlie metamorphic or igneous rocks. A nonconformity thus implies volcanism, plutonism or tectonism to produce the igneous and/or metamorphic rocks, followed by erosion to a flat surface and eventual deposition of sedimentary rocks

45. unconformity

46. Angular Unconformity –Siccar Point on the Berwickshire coast ~ 60 km east of Edinburgh, Scotland.

47. Revolution Number Two: radioactivity

48. Formula to calculate time

49. Half-life : time it takes for half of the Parent to decay (change) to the Daughter • Uranium-235 -> Lead-207 • Uranium-238 -> Lead-206 • Thorium-232 -> Lead-208 • Rubidium-87 -> Strontium-87 • Potassium-40 -> Argon-40 • Carbon-14 -> Nitrogen-14

50. During the decay Heat is given off - this is an important source of energy to produce temperatures necessary for partial melting. • alpha decay - two protons and two neutrons are emitted from the nucleus. This reduces the atomic number of the parent by 2 and the mass number of the parent by 4. Uranium to Lead Schemes