Embed Size (px)
Citation preview
ILMU KELAUTAN UNPAD ®2011
Mata Kuliah : Geologi Laut (2nd meeting)
Dosen : Muhammad Yusuf AwaluddinEmail : [email protected];[email protected]
Web : http://blogs.unpad.ac.id/myawaludin/
Outline
The Interior of the Earth
Lithophere
Astenosphere
Plate tectonics ; type of boundaries
Figure from: USGS
Interior of the Earth
•The structure of Earth's Interior :
determined from observing the
behavior of seismic waves generated
during earthquake activity.
•The main divisions are the: crust,
mantle, outer core and inner core.
•The mantle is further subdivided
into zones based on seismic wave
activity, these zones being the:
-upper mantle,
- Asthenosphere and
- the lower mantle.
Figure from: USGSThe Core
Lapisan Bumi Crust continental : 0 – 65 km (av. 40 km) depth; solid;
komposisi : silikat, potasium, sodium, alumunium
Crust Oceanic : 0-10 km (av. 7 km) depth; solid; komposisi:silikat calcium, magnesium, besi
Mantle : dasar crust – 2891 km (2866 km) depth; solid & mobile; komposisi : magnesium-iron, silicate
Outer core : 2891-5149 km (2258 km) depth; liquid ; komposisi : iron, nickel– ‘rotating fluid’
Inner Core : 5149 – 6371 km (1222 km) depth; solid;komposisi :iron, nickel
Images courtesy :mit.ocw
Lithosphere Lapisan permukaan bersifat kuat ; Crust dan Upper mantle
Ketebalan maksimum : 100 km
Ketebalan di daratan lebih BESAR daripada di Lautan (100-
200 km)
Suhu dasar mencapai 650 oC (+/- 100 oC)
Astenosphere Lapisan berada di bawah Lithosphere bersifat lemah
Bentuknya mudah berubah (deforming & flowing – saat ada
tekanan)
Mempunyai velositas seismic yang rendah
BLANK……………………
Plate Tectonics
Why and
What?
Go2: Google earth
Continental
Drift
Evolving
Seafloor
The theory of :
Plate Tectonics
Go2: Google earth
Lempeng Utama : (dalam 106 km2)
- Pasifik : 105
- African : 80
- Eurasian : 70
- Amerika Utara : 60
- Antartik : 60
- Amerika Selatan : 45
- Australian : 45
Lempeng bumi1. Lempeng Utama : (dalam 106 km2)
- Pasifik : 105
- African : 80
- Eurasian : 70
- Amerika Utara : 60
- Antartik : 60
- Amerika Selatan : 45
- Australian : 45
2. Lempeng Lebih kecil (dalam 106 km2)
- Nazca : 15
- Indian : 10
- Arabian : 8
- Philiphine : 6
- Karibian : 5
- Cocos : 5
- Scotia : 5
Figure Source: elainemeinelsupkis.typepad.com
3 types of plate boundary :
1. Divergent : move away from Each other
2. Convergent : move towards one another
3. Transform : sliding past one another
Plate Boundary typesBoundary Type of
Litosphere
Geologic process Geologic feature Earthquake Example
Divergen
(move apart)
Ocean-ocean New seafloor created, ocean basin
opens
Mid-ocean ridge Yes, shallow Mid-Atlantic
Ridge, East
Pacific Rise
Continent-
continent
Continent breaks apart, new
ocean basin forms
Continental rift,
shallow sea
Yes, shallow Gulf of Aden,
Gulf of
California
Convergent
(move together)
Ocean-ocean Old seafloor destroyed by
subduction
Ocean trench Yes, shallow -
deep
Aleutian,
Mariana
Ocean-continent Old sea floor destroyed Ocean trench Yes, shallow -
deep
Peru and
Midle
America
trenches
Continent-
continent
Mountain building Mountain range Yes, shallow -
intermediate
Himalaya,
Apls
Transform
(slide past each
other)
Ocean Seafloor conserved (neither
created nor destroyed)
Transform fault Yes, shallow Eastern
Pacific
Continent Seafloor conserved (neither
created nor destroyed)
Transform fault Ye, shallow New Zealand
Blank……………..
Tugas Kelompok
Masing-masing berjumlah 5 orang
Bahan dapat diunduh dari : http://blogs.unpad.ac.id/myawaludin/2011/09/11/tugas-critical-review-geologi-laut/
Buatlah summary dan review kritis dari bahan-bahan tersebut, diskusikandengan kelompok masing-masing.
Format tulisan minimal : Pendahuluan-Isi-Penutup, sebanyak min. 2000 kata
Tulisan dijilid mika bening cover depan dan kertas bufalo biru utk cover belakang.
Hardcopy dikumpulkan max. SELASA (20/09/11),
SOFTCOPY dikirimkan max. SENIN (19/09/11) JAM 21.00 WIB via [email protected]
