Answer: b [Reason:] Sedimentary rocks are also called secondary rocks. This group includes a wide variety of rocks formed by accumulation, compaction and consolidation of sediments.

Answer: b [Reason:] Sedimentary rocks are known to cover as much as 75 percent of the surface of the earth the rest being covered by the igneous rocks and the metamorphic rocks.

Answer: a [Reason:] Sedimentary rocks are broadly grouped into three classes on the basis of their mode of formation: Mechanically formed or Clastic rocks: Organically formed rocks and chemically rocks which are called as Non-clastic rocks.

Answer: a [Reason:] During the formation of the sedimentary rocks by mechanical method, original hard and coherent rock bodies are gradually broken down into smaller fragments. This disintegrated, loosened material is called detritus. Hence, clastic rocks are often also called as detrital rocks.

Answer: c [Reason:] The most important phenomenon that happens to the sediments during their transport and deposition is sorting or grading according to their size, shape and density.

Answer: a [Reason:] The sorting or grading occurs during the deposition stage of the formation of sedimentary rocks and the deposition happens in layers in most cases. Deposition generally takes place under ordinary pressure and temperature conditions.

Answer: c [Reason:] The process of transformation of loose sediments deposited in the settlement basins to solid cohesive rock masses either under pressure or because of cementation is collectively known as diagenesis.

Answer: b [Reason:] Welding is the process of compaction of the sediments accumulated in lower layers of a basin due to the pressure exerted by the load of the overlying sediments.

Answer: b [Reason:] Diagenesis is achieved by two methods. They are, welding and cementation. Cementation is the process by which loose grains or sediments in a settlement basin get held together by a binding material.

Answer: c [Reason:] Limestone may be formed by precipitation from carbonated water due to loss of carbon dioxide. Rock salt may be formed from sodium-chloride rich seawater merely by the process of continued evaporation.

Answer: a [Reason:] Chemically formed rocks are of two types: precipitates and evaporites. Examples are limestones, rock salt, gypsum and anhydrite.

Answer: d [Reason:] Limestones are the best examples of organically formed sedimentary rocks. Generally, the evidence of the source material gets obliterated from these rocks with the passage of time.

Answer: a [Reason:] Welding initially involves squeezing out of all or most of the water from in between the sediments, thus bringing them closer and closer and hence resulting in compaction. In fact the degree of packing of sediments in a sedimentary rock is directly proportional to the load of the overlying sediments.

Answer: b [Reason:] Animal and vegetable life, including microorganisms also contribute a fairly large supply of organic residues, which on gradual accumulation after the death of the source get compacted and turn into hard massive bodies of sedimentary rocks.

Answer: b [Reason:] Vadose water, which occurs from surface downwards up to a variable depth and is in a state of downward movement under the influence of gravity.

Answer: a [Reason:] The movement of vadose water is commonly described as infiltration. The thickness of soil and rock through which the vadose water infiltrates is called zone of aeration.

Answer: c [Reason:] Water table is the name given to the upper surface of the zone of saturation and is of fundamental importance in the study of groundwater reservoirs.

Answer: d [Reason:] Groundwater has a suitable composition in most cases and is free from turbidity, objectionable colours and pathogenic organisms requiring not much treatment.

Answer: b [Reason:] The groundwater is relatively much safe from hazards of chemical, radiogenic and biological pollution to which surface water bodies are badly exposed.

Answer: a [Reason:] Meteoric water is the water derived from precipitation (rain and snow). Although bulk of rainwater or meltwater from snow and ice reaches the sea through surface flows or run off, a considerable part of precipitation gradually infiltrates into the ground.

Answer: b [Reason:] Connate water is the water present in the rocks right from the time of their deposition in an aqueous environment.

Answer: c [Reason:] This connate water may be encountered in sedimentary rocks like limestones, sandstones and gravels. It is commonly saline in nature, and is of no importance as a source for exploitable groundwater.

Answer: c [Reason:] Juvenile water is also called magmatic water and is of only theoretical importance as far as water-supply schemes are concerned.

Answer: c [Reason:] Juvenile water is the water formed in the cracks or crevices or pores of rocks due to condensation of steam given out from hot molten masses or magmas existing below the Earth’s surface. Some hot springs and geysers are clearly derived from juvenile water.

Answer: a [Reason:] The soil water is very important for the life and growth of the vegetable cover of the globe. It is lost to the atmosphere by transpiration and evaporation.

Answer: b [Reason:] The intermediate vadose zone occurs immediately below the zone of soil water. It is in fact a zone of non-saturation: water in this zone is moving downwards under the influence of gravity.

Answer: a [Reason:] The intermediate zone is generally of small thickness and may be even absent in many cases. The soil water and intermediate zones are sometimes collectively referred as zone of aeration.

Answer: d [Reason:] The zone of capillary water, called capillary fringe is present only in the solids and rocks of fine-sized particles underlying the vadose zone. It is absent in the coarse sediments.

Answer: c [Reason:] The phreatic water zone, also called the zone of saturation lies below the capillary fringe, and it is the water held in this zone that is called groundwater in the real sense.

Answer: a [Reason:] Cataclastic structure is characterized by the development of extremely fine rock mass under the influence of severe crushing and shearing effects operating during metamorphism.

Answer: c [Reason:] The effect of shearing and crushing in the metamorphic rocks undergone metamorphism can be observed in rocks spread over wide areas. Rocks like crush breccia, mylonite and slate show this type of structure.

Answer: b [Reason:] The rock with schistose structure is made up of broadly parallel or sub-parallel layers or bands of flaky, platy or rod-like minerals making it very weak in the direction of parallelism.

Answer: c [Reason:] In gneissose structure. Bands or folia of platy and flaky minerals alternate with those of equidimensional and granular minerals.

Answer: a [Reason:] The gneissose texture is indicative of an advance degree of metamorphism under combined action of high temperature, high pressure and active participation of fluids.

Answer: d [Reason:] Maculose structure is characterized by a spotted appearance of the rock that may be caused due to the formation of large-sized crystals called porphyroblasts within an otherwise fine grained rock.

Answer: c [Reason:] Augen structure is broadly similar to maculose type and is typical of metamorphic rocks in which the effects of crushing under pressure are clearly associated with recrystallization.

Answer: c [Reason:] In augen structure, some resistant minerals get deformed into thin, lenticular, lens like shapes giving a characteristic appearance to the rock.

Answer: d [Reason:] Granulose structure is a typical structure of metamorphic rocks like marble and quartzite and is characterized by an essentially granular character of the constituent minerals.

Answer: b [Reason:] By stratification is understood a layered arrangement in a sedimentary rock. This may be developed very prominently and can be seen from a distance of miles or in other cases may have to be ascertained after close examination of the rock.

Answer: d [Reason:] The most prevalent structures of clastic group of sedimentary rocks are the ones belonging to mechanical structure which are, stratification, lamination, cross beddings, rain prints etc.

Answer: a [Reason:] Lamination is a characteristic structure of fine-grained sedimentary rocks like clays and shales.

Answer: c [Reason:] The individual layers of laminated structure are called lamiae and are distinguished commonly on the basis of difference in colour.

Answer: a [Reason:] The common types of false bedding are, tabular, lenticular, wedge shaped. Columnar is not a type of false bedding.

Answer: b [Reason:] Tabular false bedding is a type of cross bedding in which the top and bottom surfaces of the deposit are essentially parallel, indicating its deposition in the same main channel.

Answer: d [Reason:] In the case of wedge shaped cross bedding, the cross-bedding structure is highly complex: the individual layers exist in well-defined sets of parallel layers but these sets bear angular relationship to each other.

Answer: c [Reason:] In some stratified rocks the component sediments in each layer appear to be characteristically sorted and arranged according to their grain size, the coarsest being placed at the bottom and the finest at the top.

Answer: c [Reason:] Normally, perfectly graded beds are the result of sedimentation in bodies of standing water where factor of gravitative settling from a mixed load is predominant process.

Answer: a [Reason:] Mud cracks are common structural features of many fine-grained sedimentary rocks. The structure consists of polygonal or irregular cracks spread along the surface of an exposed sedimentary layer.

Answer: b [Reason:] Rain prints are irregular, small crater-shaped depressions seen on fine-grained dried sediments.

Answer: a [Reason:] The mud cracks, rain prints and ripple marks when encountered in sedimentary formations are taken as confirmatory evidence of the formation having been deposited in a shallow water environment.

Answer: c [Reason:] The Oolitic structure is the structure where, the concretions are of the size of fish eggs; the rock appears as an assemblage of fish eggs.

Answer: b [Reason:] The pisolitic structure is another type of concretionary structure where, the individual size of a concretion is like that of a peanut. Limestones and bauxite show both these structures.

Answer: c [Reason:] The science dealing with the study of earthquake in all their aspects is called seismology. It is interdisciplinary science, which is partly geology and partly physics.

Answer: c [Reason:] The place or point of origin of an earthquake below the surface of the earth is termed as its focus or hypocenter. It may lie from a few hundred meters to hundreds of kilometres below the surface.

Answer: a [Reason:] The point or place on the surface vertically above the focus of a particular earthquake is termed as its epicentre.

Answer: b [Reason:] The epicenter is that place on the surface of the earth where the vibrations from a particular earthquake reach first of all. It is often the location of maximum damage in that event.

Answer: c [Reason:] As regards the distance from epicenter to focus, or depth of focus, it has been observed from the study of seismic records that no earthquake with a focus deeper than 700 km has been recorded so far.

Answer: a [Reason:] The P-waves are also called the primary waves, push and pull waves, longitudinal waves and compressional waves. These are the fastest of the seismic waves and are longitudinal in character.

Answer: a [Reason:] The S-waves are also called secondary waves, the shear waves, the transverse waves or the distortional waves. These waves are transverse in character, like the light waves.

Answer: b [Reason:] The S-waves would not propagate through a liquid medium at all. This is a proven fact with S-waves and has helped geologists a lot in understanding the nature of the core of the earth.

Answer: c [Reason:] The P and S-waves are sometimes collectively referred as body waves because they travel deep into the body of the Earth before re-emerging on the surface.