Which of the following is NOT a Direct source for obtaining information about the interior of earth?
Explanation: This and many deep drilling projects have provided large volume of information through the analysis of materials collected at different depths. Volcanic eruption forms another source of obtaining direct information. As and when the molten material (magma) is thrown onto the surface of the earth, during volcanic eruption it becomes available for laboratory analysis. However, it is difficult to ascertain the depth of the source of such magma. Analysis of properties of matter indirectly provides information about the interior. We know through the mining activity that temperature and pressure increase with the increasing distance from the surface towards the interior in deeper depths. Moreover, it is also known that the density of the material also increases with depth. It is possible to find the rate of change of these characteristics. Knowing the total thickness of the earth, scientists have estimated the values of temperature, pressure and the density of materials at different depths. The details of these characteristics with reference to each layer of the interior are discussed later in this chapter.
Consider the following statements:
Which of the above statement(s) is/ are correct?
Explanation: All natural earthquakes take place in the lithosphere. Earthquake waves are basically of two types — body waves and surface waves. Body waves are generated due to the release of energy at the focus and move in all directions travelling through the body of the earth.
Which of the following statements is correct?
The Mercalli Scale is based on observable earthquake damage. From a scientific standpoint, the magnitude scale is based on seismic records while the Mercalli is based on observable data which can be subjective.
The Mercalli intensity scale (or more precisely the Modified Mercalli intensity scale) is a scale to measure the intensity of earthquakes. Unlike the Richter scale, the Mercalli scale does not take into account energy of an earthquake directly.
Which types of volcanic eruptions have caused Deccan Trap formations?
Caldera type of volcanic eruption has caused deccan trap formation.The Deccan Traps are one of the largest volcanic provinces in the world. It consists of more than 6,500 feet (>2,000 m) of flat-lying basalt lava flows and covers an area of nearly 200,000 square miles (500,000 square km) (roughly the size of the states of Washington and Oregon combined) in west-central India.
Which of the following statements about ‘Tillite’ is correct?
Tillite, sedimentary rock that consists of consolidated masses of unweathered blocks (large, angular, detached rock bodies) and glacial till (unsorted and unstratified rock material deposited by glacial ice) in a rock flour (matrix or paste of unweathered rock). The matrix, which comprises a large percentage of the rock, usually is dark gray to greenish black in colour and consists of angular quartz and feldspar grains and rock fragments in a very fine-grained paste. The widespread tillites in the geologic record provide evidence of former intense and widespread glaciation; Recent tillites (less than 11,700 years old) can be directly connected with glaciation, and Pleistocene tillites (11,700 to 2,600,000 years old) can be convincingly related to glaciation, but many earlier till-like bodies cannot. Only tillites formed from the till deposited by continental ice sheets have a good chance of being preserved in the geologic record.
Which of the following statements is/are correct?
The second statement is wrong because the intensity of Sun rays falling on the ocean near equator is more than that of the pole. Thereby, the temperature, as we move up from the equator to the poles, decreases.
The height of a wave is determined by its ____
Explanation: A wave’s size and shape reveal its origin. Steep waves are fairly young ones and are probably formed by local wind. Slow and steady waves originate from faraway places, possibly from another hemisphere. The maximum wave height is determined by the strength of the wind, i.e. how long it blows and the area over which it blows in a single direction.
According to Wegner which of the following forces were responsible for the drifting of the continents?
Wegener suggested that the movement responsible for the drifting of the continents was caused by pole-fleeing force and tidal force. The polar-fleeing force relates to the rotation of the earth. You are aware of the fact that the earth is not a perfect sphere; it has a bulge at the equator. This bulge is due to the rotation of the earth. The second force that was suggested by Wegener—the tidal force—is due to the attraction of the moon and the sun that develops tides in oceanic waters.
Which one of the following is the type of plate boundary of the Indian plate along the Himalayan mountains?
Explanation: The Indian plate includes Peninsular India and the Australian continental portions. The subduction zone along the Himalayas forms the northern plate boundary in the form of continent— continent convergence.
Which of the following statements is correct?
Explanation: Point bars are also known as meander bars. They are found on the convex side of meanders of large rivers and are sediments deposited in a linear fashion by flowing waters along the bank Meander is not a landform but is only a type of channel pattern. This is because of (i) Propensity of water flowing over very gentle gradients to work laterally on the banks; (ii) unconsolidated nature of alluvial deposits making up the banks with many irregularities which can be used by water exerting pressure laterally; (iii) coriolis force acting on the fluid water deflecting it like it deflects the wind.
Meanders develop over flood and delta plains.
Which of the following is NOT a permanent gas of the atmosphere?
Explanation: Permanent Gases of the Atmosphere
Which of the following statements is NOT correct?
Explanation: Water vapour is also a variable gas in the atmosphere, which decreases with altitude. Water vapour also decreases from the equator towards the poles. It also absorbs parts of the insolation from the sun and preserves the earth’s radiated heat. It thus, acts like a blanket allowing the earth neither to become too cold nor too hot. Water vapour also contributes to the stability and instability in the air.
Choose the correct option:
Assertion (A): The gravitation force (g) is greater near the poles and less at the equator.
Reason(R): This is because of the distance from the centre at the equator being greater than that at the poles.
Gravitational force near the poles is greater because poles are nearer to the center of earth than the equator and gravitational force is inversely proportional to the square of distance.
Mark the incorrect among the following:
Explanation: The release of energy occurs along a fault. A fault is a sharp break in the crustal rocks. Rocks along a fault tend to move in opposite directions. As the overlying rock strata press them, the friction locks them together. However, their tendency to move apart at some point of time overcomes the friction. As a result, the blocks get deformed and eventually, they slide past one another abruptly. This causes a release of energy, and the energy waves travel in all directions.
The Mohorovicic discontinuity refers to
The Mohorovičić discontinuity ,usually referred to as the Moho, is the boundary between the Earth's crust and the mantle.The Moho lies almost entirely within the lithosphere.
Arrange the following in chronological order
The Cenozoic is divided into three periods: the Paleogene, Neogene, and Quaternary; and seven epochs: the Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, and Holocene. The Quaternary Period was officially recognized by the International Commission on Stratigraphy in June 2009,and the former term, Tertiary Period, became officially disused in 2004 due to the need to divide the Cenozoic into periods more like those of the earlier Paleozoic and Mesozoic eras. The common use of epochs during the Cenozoic helps paleontologists better organize and group the many significant events that occurred during this comparatively short interval of time. Knowledge of this era is more detailed than any other era because of the relatively young, well-preserved rocks associated with it.
Which of the followings is/are NOT the components of a map?
Maps contain lots of information. Most maps will have the five following things: a Title, a Legend, a Grid, a Compass Rose to indicate direction, and a Scale. The Title tells you what is being represented on the map (i.e. Austin, Tx). The legend (also know as the key) explains the symbols used on the map for various features like mountains or rivers and other major landmarks. Next, there is usually a grid made up of longitude and latitude lines to precisely locate specific locations. Then, there is the compass rose indicating the cardinal directions of North, South, East, and West as it relates to the map. Finally, the scale compares the distances on the map to actual distances (i.e. 1 inch = 10 miles).
What is not true about Feldspar?
Explanation: Feldspar: Silicon and oxygen are common elements in all types of feldspar and sodium, potassium, calcium, aluminium etc. are found in specific feldspar variety. Half of the earth’s crust is composed of feldspar. It has light cream to salmon pink colour. It is used in ceramics and glass making.
The direction of wind around a low pressure in northern hemisphere is:
The direction of the wind around a low-pressure system in the northern hemisphere rotates counterclockwise while the high-pressure system rotates clockwise. For low pressure, the wind moves right to left direction towards the centre of the system.
Consider the following statements about jet Stream circulations choose the correct ones:
Choose the correct answer—
The jet stream is a current of fast moving air found in the upper levels of the atmosphere. This rapid current is typically thousands of kilometers long, a few hundred kilometers wide, and only a few kilometers thick. Jet streams are usually found somewhere between 10-15 km (6-9 miles) above the earth's surface.
Jet streams are usually found somewhere between 10-15 km (6-9 miles) above the earth's surface. The position of this upper-level jet stream denotes the location of the strongest SURFACE temperature contrast.
The winds blow from west to east in jet streams but the flow often shifts to the north and south. Jet streams follow the boundaries between hot and cold air. Since these hot and cold air boundaries are most pronounced in winter, jet streams are the strongest for both the northern and southern hemisphere winters.
A meridian is
A meridian circle is any circle on the surface of the earth passing through both the north and south poles. The longitude of a station is defined as the angular distance measured along the arc of the equator between a primary meridian, which is a reference meridian, and the meridian circle passing through the station.
Excluding the moon, the celestial object that generally appears bright in the sky is
Venus is one of the brightest objects in the night sky. Venus is so bright because its thick clouds reflect most of the sunlight that reaches it (about 70%) back into space, and because it is the closest planet to Earth. Venus can often be seen within a few hours after sunset or before sunrise as the brightest object in the sky (other than the moon). It looks like a very bright star. Venus is the brightest planet in the Solar System.
Lines joining places of equal rainfall are known as
An isohyet is also known as isohyetal line, and it is a line on a map which connects points that have the same amounts of precipitation in a given period or for a particular storm. The method used in estimating average rainfall across a particular area is known as an isohyetal method.
Atoll refers to
An atoll sometimes called a coral atoll, is a ring-shaped coral reef including a coral rim that encircles a lagoon partially or completely. There may be coral islands or cays on the rim. The coral of the atoll often sits atop the rim of an extinct seamount or volcano which has eroded or subsided partially beneath the water. The lagoon forms over the volcanic crater or caldera while the higher rim remains above water or at shallow depths that permit the coral to grow and form the reefs. For the atoll to persist, continued erosion or subsidence must be at a rate slow enough to permit reef growth upward and outward to replace the lost height.
What does 'Roaring forties' refer to?
The region between latitudes 40° and 50°S, where the prevailing westerly winds blow over the open oceans with great regularity and strength
The Roaring Forties are strong westerly winds found in the Southern Hemisphere, generally between the latitudes of 40 and 50 degrees. The strong west-to-east air currents are caused by the combination of air being displaced from the Equator towards the South Pole, the Earth's rotation, and the scarcity of landmasses to serve as windbreaks.