The atmosphere and Earth’s interior are layered by density. Gravity pulls more strongly on denser materials so denser materials are at the center of things. Earth’s core, at its center, is denser than its crust. The lowest layer of the atmosphere is denser than the upper layer.
Q. Which process is involved when the oceanic crust plunges down into the mantle?
subduction
Q. What happens to old oceanic crust as new molten material rises from the mantle?
What happens to old oceanic crust as new molten material rises from the mantle? It is recycled back into the mantle through the process of subduction. The process of subduction also plays a role in the new molten material rising from the mantle (see page 132).
Q. What is responsible for seafloor spreading?
Seafloor spreading and other tectonic activity processes are the result of mantle convection. Seafloor spreading occurs at divergent plate boundaries. As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense.
Q. Why is seafloor spreading important?
Significance. Seafloor spreading helps explain continental drift in the theory of plate tectonics. When oceanic plates diverge, tensional stress causes fractures to occur in the lithosphere. At a spreading center, basaltic magma rises up the fractures and cools on the ocean floor to form new seabed.
Q. What are the relief features of ocean?
The Oceanic relief features are in the form of mountains, basins, plateaus, ridges, canyons and trenches beneath the ocean water. These forms are called Submarine Relief.
Q. What are bathymetric features?
Bathymetric features such as the continental shelf and seamounts interact with ocean currents and winds to produce regions of upwelling, where nutrient-rich waters are brought to the surface. This nutrient-rich water supports high levels of primary production by phytoplankton, which in turn attracts larger organisms.
Q. What are the relief features?
relief features are those features which are related to landscape of those areas, eg. mountains, altitude, valleys, types of land and heights of mountains.
Q. Is River a relief feature?
Natural features include relief, which is sometimes mistakenly understood to be the sole feature characterizing a topographic map, and hydrographic features, such as lakes and rivers; man-made features include other characteristics of the subject area, such as cities, towns, and villages, and roads, railroads, canals.
Q. Why are they called relief features?
Relief is typically defined as the difference in height between the high point and the low point on a landscape, in feet or in meters. It is called a “relief-like” map, since it uses various colors and shading to shows areas of different elevation, and some shadowing to highlight steep slopes.
Q. What is first order relief features of the earth?
First order relief – refers to the coarsest level of landforms, including continental platforms and ocean basins. 2. 3. Third order relief – most detailed order of relief includes things like mountains, cliffs, valleys, hills, and other small scale landforms.
Q. What are the landforms of the first and second order?
- First Order of Relief. The broadest category of land forms includes huge continental platforms and ocean basins.
- Second Order of Relief. In the ocean basins, the second order of relief includes continental rises, slopes, abyssal plains, mid-ocean ridges, submarine canyons, and subduction trenches.
- Third Order of Relief.
Q. What are known as second order landforms?
Answer: Examples of second order landforms are plateaus, plains, mountains, and continental slope and shelf on the ocean bottoms.
Q. What are 1st and 2nd order landforms?
First order landforms: Continents and oceans. Continents are the huge land masses on Earth. Huge water bodies are called Oceans….Theory:
| First-order landforms | Second-order landforms | Third-order landforms |
|---|---|---|
| Continents Oceans | Mountains Plateaus Plains | Valleys Beaches Sand dunes |
Q. How many orders of landforms are there?
A landform is a feature on the Earth’s surface that is part of the terrain. Mountains, hills, plateaus, and plains are the four major types of landforms. Minor landforms include buttes, canyons, valleys, and basins.
Q. What are the examples of first order landforms?
First order landforms: Continents and oceans. Continents are the huge land masses on Earth. Huge water bodies are called Oceans….Seven continents are:
- Asia.
- Africa.
- North America.
- South America.
- Antarctica.
- Europe and.
- Australia.
Q. What are the first order of landforms?
The first order landforms are continents and ocean basins.
Q. What are the 10 landforms?
Earth Sciences: Types of Landforms
- Mountains. Mountains are landforms higher than the surrounding areas.
- Plateaus. Plateaus are flat highlands that are separated from the surroundings due to steep slopes.
- Valleys.
- Deserts.
- Dunes.
- Islands.
- Plains.
- Rivers.
Q. What is the Himalayas order of landforms?
They are designated, from south to north, as the Outer, or Sub-, Himalayas (also called the Siwalik Range); the Lesser, or Lower, Himalayas; the Great Himalaya Range (Great Himalayas); and the Tethys, or Tibetan, Himalayas.
Q. How are landforms classified?
Landforms are categorized by characteristic physical attributes such as elevation, slope, orientation, stratification, rock exposure, and soil type. Mountains, hills, plateaux, and plains are the four major types of landforms. Minor landforms include buttes, canyons, valleys, and basins.
