Earthquakes and volcanoes - class-VIII
In which of the following continent, there is no active volcano?
There are no volcanoes on the Australian mainland that have erupted since European settlement, but some volcanoes in Victoria, South Australia, and North Queensland were witnessed by Aboriginal people several thousand years ago.
The area associated with the greatest frequency of earthquakes is ____________________.
The point from where earthquake originates is called ____________.
An earthquake is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves.
An earthquake's point of initial rupture is called its focus or hypocenter. The epicenter is the point at ground level directly above the hypocenter.
Sometimes hot molten rocks formed inside the earth are forced out through openings in the earth's surface such as the craters in volcanoes. What is the molten rock inside the earth called?
The Himalayas are generally divided into three ranges which do not include:
The Himalayas are generally divided into three ranges which are Siwalik, Greater Himalayas and Lesser Himalayas. The Karakoram or Karakorum is a large mountain range spanning the borders of Pakistan, India, and China, with the northwest extremity of the range extending to Afghanistan and Tajikistan.
Tick the correct answer.
Which the largest continent?
Asia is the largest continent. It covers about one-third of the total land area of the earth. The continent lies in the Eastern Hemisphere.
Which of the following is the farthest from the centre of the earth?
Tectonic plates float independently over the _________.
The movement of tectonic plates is due to thermal energy from _______.
The movement of tectonic plates is due to the enormous amount of thermal energy generated in the inner core and transferred to the mantle thus, causing movement in the tectonic plates.
Collisions of plates produce mountain ranges and other irregular surface features in ________.
In the transform boundary, the plates ________.
What is the location where sinking of plate occurs called?
How many million years ago, Indian Plate was a part of Gondwanaland?
The Gondwanaland, comprised of modern Africa and _________.
Continental Plates are _________.
The great rift valley of East Africa is a notable example for the process of ________.
According to plate tectonics, the plates are in constant motion with an average rate of ________ per year.
In Convergent boundary, plates __________.
The fragmented outermost layers of earth are known as _____.
Currently, geologists are working on the theory of plate tectonics. Geologically speaking, a "plate" is a large, rigid slab of rock. The theory of plate tectonics states that the earth's outermost, rigid layer, the lithosphere, is fragmented into a dozen or more irregularly shaped plates that are riding atop a hotter, more mobile material, the asthenosphere.
Wettest place on Earth is _____________.
Sohra (temporarily called Cherrapunjee or Cherrapunji) is a subdivisional town in the East Khasi Hills district in the Indian state of Meghalaya. Sohra has often been credited as being the wettest place on Earth, but for now nearby Mawsynram currently holds that distinction.
Tectonic plate boundaries may be _________.
There are three kinds of plate tectonic boundaries: divergent, convergent, and transform plate boundaries. A divergent boundary occurs when two tectonic plates move away from each other. When two plates come together, it is known as a convergent boundary.
Which of the following movement give rise to continents?
The word Epeirogenetic consists of two words viz, 'epiros' means continent and 'genesis' means origin. So eperiogenetic movement gives rise to the continent. Epeirogenetic movement causes upliftment and subsidence of continental masses through upward and downward movements respectively. Both, the movements are vertical movement.
The movements in the interior of the earth caused by continuous and slow emission of energy are called _____________.
The Powerful internal forces operating from within the crust are called Earth Movements which bring about vast changes on the earth's surface are called Earth Movements. They may be slow and sudden. Slow movements occurs at a very slow rate and continue much longer as compared to our life span. These movements are relative to each other, the land advancing against sea is termed as negative movement and the sea advancing on land is known as positive movement.
Mountains and continents are formed due to ___________.
Mountain and continents are formed due to slow earth movement. Slow forces include both vertical and horizontal movements which are caused due to forces deep within the earth. These forces operate very slowly and their effects become discernible after thousands and million of year.
The surface relief of the earth is moulded by which of the following forces?
When the tectonic plates move away from each other it is called _____________.
How many major tectonic plates are there on earth?
There are seven main or “primary” tectonic plates: these are the African Plate: Antarctic Plate, Eurasian Plate, Indo-Australian Plate, North American Plate, Pacific Plate, and South American Plate.
From which sea the Himalayan mountain was emerged?
In which one of the following is the Himalayan pass Shipki La located?
In Sutlej valley the Himalayan pass Shipki La is located. A spur road on the Indian side rises to an altitude of 4,720 metres (15,490 ft) four km southwest of Shipki La. It is located in Kinnaur district in the state of Himachal Pradesh, India, and Ngari Prefecture in Tibet, China.
Match the following:
|Mountain passes in Himalayas||States|
|A.||Chang la||1.||Arunachal Pradesh|
|B.||Shipki la||2.||Himachal Pradesh|
|C.||Zoji la||3.||Jammu and Kashmir|
|D.||Bomdi la||4.||Jammu and Kashmir|
Mountain passes in Himalayas States
The Indian sub-continent was originally part of ________.
Slow movements take place in _________ direction.
Vertical movements are responsible for the rise or fall of a portion of the earth surface. Vertical movements of the earth do not disturb the horizontality of the strata. Vertical movements cause uplift and subsidence.
The movements that give rise to mountains are called ______________.
The word Orogeny is derived from a Greek word 'Oros' meaning mountain. The orogenic movements are due to horizontal forces in earth's crust, as a result of which rock-strata are crumpled and folded. It is this movement that give rise to mountains.
Tick the correct answer.
The mountain range that separates Europe from Asia is
Asia is separated from Europe by the Ural mountains on the west (Figure 5.1). The combined landmass of Europe and Asia is called Eurasia (Europe + Asia).
Which one of the following is most prone to earthquakes?
Which of the following rocks are formed from the volcanoes?