GEOGRAPHY | Rikako's fresh blog

Aug 31

Marine Processes

Posted by 15hatoyar under GEOGRAPHY No Comments »

Aim

types of waves
component of waves
erosional processes: corrasion, corrosion, hydraulic action, attrition
onshore and offshore movement
longshore drift
wind actions and dunes

Waves

energy transmitted through matter
the medium (solid liquid gas) does not actually travel as the energy passes, but its particles vibrate as the energy passes through
Progressive waves
Size of wave depends on fetch= distance a wave travels
The greater the fetch, the larger the wave
The stronger the wind, the larger the wave
As the wave approaches the beach, it slows down due to friction between water and beach, and this causes the wave to break.
terms: break, swash, backwash
If swash is bigger than backwash, more deposition occurs so beach is created. If backwash is bigger than swash, beach is destroyed
Destructive waves destroy beaches. Back wash has less time to soak into sand. So it carries a lot of sand with it. As waves continue to hit the beach, more running water carry material to the sea.
Wind generated waves originate in windy places of the ocean
They keep on moving along large areas without the aid of wind
As wind blows over ocean surface, it creates pressure that deform the surface of the ocean
If power increases, it becomes gravity waves

May 24

Prevention and Cause of volcanic eruptions

Posted by 15hatoyar under GEOGRAPHY No Comments »

Definitions for commonly used terms

Hazard- thing (usually has dates)

Risk- chance/likeliness

Disaster- occurence

Volcanic Features

Eruption column and cloud- volcanic ash emitted during volcanic explosion. Ash forms a column rising many km into air above peak of volcano. Eruption cloud- cloud that forms when volcano erupts. Lung problems, harm ecosystem.

Volcanic gases- Gas ejected of volcanoes during eruption.

Lava flow and domes- Lava dome is created by volcanic eruption. Forms when lava flow is too thick to flow, and piles up on the side, creating a steep side. Lava flow- movement of lava created during non-explosive eruption.

Pyroclastic Flows- Flow of ash, rocks, and gas down the volcano, carrying everything on its pathway.

Lahars- Type of mudflow, contains: pyroclastic material, rocky debris, and water. Over 60km/hour. Material flows down volcano, occurs along river valley.

Edifice collapse- Structure of volcano collapse.

Hot springs and Geysers- Hot springs- Warm water above body temperature. Heated naturally. Above ground. Geyser- When spring releases hot water and steam into water, from hole in ground. Occurs due to build up of pressure.

Other notes: http://greenfieldgeography.wikispaces.com/IGCSE+Plate+Tectonics+and+GCSE+Plate+Tectonics

Noted from video.

Apr 26