GEOLOGY FREE NOTES

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 1) Inhaling the smoke from a burning _________ could _________ you quickly. (A) tire / tier (B) tire / tyre (C) tyre / tire (D) tyre / tier Solution : I nhaling smoke from a burning tyre (rubber covering of a wheel) is harmful. The verb tire means to cause fatigue or exhaustion , which fits the context of the sentence ("could tire you quickly"). Solution : For the sphere to fit: The diameter of the sphere must equal the side length of the cube. Side length of the cube=Diameter of the sphere=2r Now volume = (2r) 3 = 8 r 3 3) Pipes P and Q can fill a storage tank in full with water in 10 and 6 minutes, respectively. Pipe R draws the water out from the storage tank at a rate of 34 litres per minute. P, Q and R operate at a constant rate. If it takes one hour to completely empty a full storage tank with all the pipes operating simultaneously, what is the capacity of the storage tank (in litres)? (A) 26.8 (B) 60.0 (C) 120.0 (D) 127.5 Solution : Le...

 1) The fishermen, _______ the flood victims owed their lives, were rewarded by the government. (A) whom (B) to which (C) to whom (D) that Solution: The phrase "owed their lives" requires a preposition ("to") to indicate the direction of the action . The flood victims owe their lives to the fishermen. Hence, "to whom" is grammatically necessary to convey this relationship. "Whom" is used in formal English as the object of a verb or preposition. In this case, "to whom" is the object of the verb "owed" and the preposition "to." 2) Some students were not involved in the strike. If the above statement is true, which of the following conclusions is/are logically necessary? 1. Some who were involved in the strike were students. 2. No student was involved in the strike. 3. At least one student was involved in the strike. 4. Some who were not involved in the strike were students. (A) 1 and 2 (B) 3 (C) 4 (D) 2 and 3 Solutio...

  TYPES OF VOLCANISM 1) Interplate volcanism Associated with tectonic activity Mainly occurs during Subduction of plates Region of volcanic ar c: High temp but low pressure Region of Subduction zone : High pressure but low tem p Source of volcanic material: asthenosphere Composition : Tholeitic, Calc-Alkaline and Alkaline Example : Ocean- Ocean convergence : Andaman Nicobar, Japan, Mariana Trench, Aleutian, Ocean - Continent convergence : Andean, Peru chile trench 2) Intraplate volcanism Associated with hotspot activity (within the plate) S ource of volcanic material is D’’- layer Composition: Tholeitic and Alkaline Example: Hawaiian volacano (OIB) , Yellowstone volcanism , Deccan (CFB) MAGMA SERIES TYPES Magma series is divided into two types: 1) Alkaline series Found in convergent plate margins and oceanic, continental intraplate settings Restricted to intraplate occurences Higher melt fractions and high pressure (highly incompatible) Melting at high pressure leads to nephelin...

  Thrust surfaces usually have stair-case geometry. FLAT Sub-horizontal or gently-dipping (at the time of initiation) part of a thrust. Fault segments running parallel to each other RAMP The moderately-dipping part (at the time of initiation) of a thrust. Ramps usually climb up-section across stiffer layers. Fault segments cutting across the beddings Hanging wall flat (HWF) : The portion of the thrust where the fault is parallel to the bedding surfaces on the hanging wall side. Hanging wall ramp (HWR) : The portion of the thrust where the f ault is oblique to the bedding surfaces on the hanging wall side. Footwall flat (FWF): The portion of the thrust where the f ault is parallel to the bedding surfaces on the footwall side. Footwall ramp (FWR): The portion of the thrust where the fault is oblique to the bedding surfaces on the footwall side. Frontal ramp : Strike of the ramp is perpendicular to the regional tectonic transport direction. Lateral ramp : Strike of the ramp is p...

  If bed dip upstream: V point upstream Dip of the bed is gentler than contours For Horizontal beds : V point upstream Dip of the bed is same as contours Bed dip gently downstream: V point upstream Dip of the bed is sharper or little steeper than contours Bed dip with stream gradient: No v shape Bed dip steeply downstream: V point downstream (only case) Bed is vertical No v shape QUESTIONS 1) A plunging fold will NOT show a V-shaped outcrop pattern on a planar ground surface if the plunge of the fold axis is (JAM-2024) (A) equal to the dip of the ground surface in the same direction  (B) steeper than the dip of the ground surface in the same direction  (C) equal to the dip of the ground surface in the opposite direction  (D) steeper than the dip of the ground surface in the opposite direction Solution:         There are two conditions when we can't get any V-shape If the beds are vertical If the beds dip with stream gradient i.e dip of t...

  METAMORPHIC REACTIONS It is an expression of how the minerals got to their final state It is a chemical reaction that produces, or changes, an assemblage of metamorphic mineral and fluid phases in a rock. POLYMORPHIC TRANSFORMATIONS Chemical composition remains same Mineralogy will change with change in temperature and pressure Isochemical reaction Depends upon tempearature and pressure but not on partial pressure of fluid          Ex: Polymorphism of SiO2, Aluminosilicates, Graphite-Diamond, Calcite-Aragonite EXSOLUTION REACTIONS Occur in solid-solution mineral series when a solvus is encountered The process involves the unmixing of the solid solution within the composition range covered by the solvus.                                                                        ...

 1) The untimely loss of life is a cause of serious global concern as thousands of people get killed ______ accidents every year while many other die ______ diseases like cardio vascular disease, cancer, etc. (A) in, of (B) from, of (C) during, from (D) from, from Solution : People are killed in accidents. People die of diseases like cardiovascular disease, cancer, etc. "in" accidents : The preposition "in" is commonly used to describe someone being involved in an event or situation , such as an accident. We say "killed in accidents" to indicate the event where the fatalities occurred. "of" diseases : T he preposition "of" is used to indicate the cause of death, particularly when referring to diseases. People "die of diseases" because the disease is the direct cause of their death. 2) He was not only accused of theft ______ of conspiracy. (A) rather (B) but also (C) but even (D) rather than Solution : "not only... bu...

 1) The people ___________ were at the demonstration were from all sections of society. (A) whose (B) which (C) who (D) whom Solution : The correct answer is "who" because it is a relative pronoun used to refer to people. Here’s why the other options are incorrect: "whose" : This is a possessive form and is used to indicate ownershi p, which doesn’t fit the context of the sentence. "which" : This is used for non-human objects or animals , so it’s not appropriate when referring to people. "whom" : This is used as an object of a verb or preposition , but the sentence requires a subject pronoun to describe "the people." 2) Solution: Ans(C) • The vertical line of the "K" remains in the same position. • The left diagonal line of the "K" will be reflected to the right side, forming a mirrored diagonal. • The right diagonal line of the "K" will be reflected to the left side, forming a mirrored diagonal. • Th...

  Isostasy is the gravitational equilibrium between earth’s crust and mantle gravitational balance AIRY’S THEORY Equal density and unequal thickness It is based on root and anti-root theory Root : in case of high elevation (mountain) Anti-root : in case of low elevation (ocean)       Root = ρch/(ρm-ρc)       Anti-root = (ρc-ρw)z / (ρm-ρc)       h= height of mountain       z = depth of ocean PRATT’S THEORY Unequal density at uniform depth Not based on root and anti-root       ρ = ρcD/(D+h)       ρ' = (ρcD - ρwZ)/(D-z)      D= thickness of crust      z=depth of ocean VENING MEINESZ The upper layer behaves like an elastic plate overlying a weak fluid. It accounts for regional isostatic compensation Depends on elastic properties of the lithosphere Local compensation : Airy’s and Pratt’s theory Regional compensation : Vening meinesz theory ISOSTATIC COMPENSATION Gr...

  SEQUENCE STRATIGRAPHY  TRANSGRESSION Shoreline shift landward Retrogradational pattern - fining upward Feature name - Estuaries Sea level rise Deepening upward (Deep facies found at the top whereas shallow facies found at the bottom) Transgressive system tract found - due to rapid increase in sea level REGRESSION Shoreline shifts seaward either due to sedimentation - Normal regression due to sea level fall - Forced regression Regression is of two types 1) NORMAL REGRESSION Shoreline shift seaward due to sedimentation Low stand system tract, High stand system tract 2) FORCED REGRESSION Shoreline shift seaward due to rapid fall in sea level Falling stage system tract - rapid decrease in sea level Coarsening upward - Progradational pattern SYSTEM TRACTS 1) FSST - Rapid fall in sea level : Forced regression 2) LST - Sea level just start rising (initial stage when sea level start rises) 3) TST - rapid rise in sea le ve l : Transgression (retrogradation pattern) 4) HST...