GATE 2026 Question Paper Geology and Geophysics - Geophysics (GG-2)

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GATE 2026
Question Paper ·
Geology Geophysics
Geophysics (GG 2)
EXAM YEAR TYPE SUBJECT

GATE 2026 Question Paper Geology Geophysics Geophysics (GG 2)

Notes · Sample Papers · Previous Year Papers · Mock Tests

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Geology & Geophysics (GG)

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General Aptitude (GA)
Q.1 – Q.5 Carry ONE mark Each

Q.1 Suresh said, “I did it yesterday.”

Which one of the following options is the correct form of this sentence in indirect
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speech?

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(A) a Suresh said that I did it yesterday.

(B) Suresh says I did it yesterday.

(C) Suresh says that he did it the day before.

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(D) Suresh said that he had done it the day before.

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Geology & Geophysics (GG)

Q.2 To continue the sequence of tiles shown, the tile indicated by the question mark
should be

(A)

(B)

(C)

(D)

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Geology & Geophysics (GG)

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Q.3 Consider an art gallery whose walkways are shown as lines in the diagram. A
black dot represents a junction of two walkways. A guard may be placed at a
junction to watch over the walkways that join at that junction. The minimum
number of guards needed to watch all the walkways is ________.

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(A) 2
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(B) 3
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(C) 4 a
(D) 5

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Geology & Geophysics (GG)

Q.4 The 2nd of June is a Thursday in a certain year. Which day of the week is the
3rd of July in that year?

(A) Thursday

(B) Friday

(C) Saturday

(D) Sunday

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Geology & Geophysics (GG)

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Q.5 A coin with heads facing up is shown as and a coin with tails facing up is
shown as .

Six coins are placed in the Starting Arrangement, as shown in the figure below.
A “step” is defined as interchanging a pair of adjacent coins without flipping
them. The minimum number of steps needed to go from the Starting Arrangement
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to the Final Arrangement, as shown in the figure, is ________.
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(A) 3

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(B) 6

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(C) 9
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(D) 12

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Geology & Geophysics (GG)

Q.6 – Q.10 Carry TWO marks Each

Q.6 Exacerbate : Mitigate :: ___________

Choose the option with the correct pair of words to fill the blank.

(A) Aggravate : Alleviate

(B) Alleviate : Precipitate

(C) Aggravate : Precipitate

(D) Emancipate : Exonerate

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Geology & Geophysics (GG)

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Q.7 A paper shown in Panel I is folded along the dashed lines (- - -) to construct a
cube. The shaded regions shown in Panel I appear on the outer surface of the cube.
Referring to cubes shown in Panel II, which one of the options is correct?

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(A) Only (i) can correspond to the unfolded cube in Panel I.

(B) Only (ii) can correspond to the unfolded cube in Panel I.

(C) Both (i) and (ii) can correspond to the unfolded cube in Panel I.
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(D) Neither (i) nor (ii) can correspond to the unfolded cube in Panel I.

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Geology & Geophysics (GG)

Q.8 In a population, patients who have high cholesterol also have high blood-pressure
(BP). Some patients with high BP also have diabetes. There are no patients who
have both high cholesterol and diabetes. Furthermore,

1. the total number of patients with at least one of these conditions is 75,
2. the number of patients with high cholesterol is 10,
3. the number of patients with high BP is 45, and
4. the number of patients with only high BP and no other conditions is 20.

Then the number of patients who have both diabetes and high BP is _______

(A) 0

(B) 15

(C) 20

(D) 10

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Geology & Geophysics (GG)

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Q.9 Four people P, Q, R, and S, of different ages, make the following observations.

P – I am younger than S.

Q – I am neither the youngest nor the oldest.

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Based on these observations, the youngest person is ______.
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(A) P

(B) Q

(C) R
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(D) S
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Geology & Geophysics (GG)

Q.10 Circles 𝐶1 , 𝐶2 , and 𝐶3 , with centers 𝑂1, 𝑂2, and 𝑂3 , and radii 𝑟1 , 𝑟2 , and 𝑟3 ,
respectively, touch each other as shown in the following figure. Given 𝑟1 = 2 cm,
𝑟2 = 1 cm and the angle ∠𝑂1 𝑂3 𝑂2 is 90°, 𝑟3 = _____ cm.

(A) 1
(−3 + √17 )
2

(B) 1
(3 + √17 )
2

(C) 1
(−2 + √17 )
2

(D) 1
(−3 + 2√17 )
2

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Geology and Geophysics (GG)

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PART A: COMPULSORY SECTION FOR ALL CANDIDATES
Q.11 – Q.17 Carry ONE mark Each

Q.11 Which one of the following increases over time when the soil is fully saturated?

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(A)
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Infiltration
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(B) a Runoff

(C) Porosity

(D) Permeability

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Q.12 In which one of the following layers inside the Earth, the velocity of the P-wave
exceeds 13 km/s?
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(A) Upper mantle

(B) Outer core
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Lower mantle

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Geology and Geophysics (GG)

Q.13 Which one of the following is NOT a volcanic igneous rock?

(A) Dacite

(B) Syenite

(C) Trachyte

(D) Komatiite

Q.14 If 𝑟1 and 𝑟2 , respectively, denote the equatorial and polar radii of a reference
ellipsoid, then the radius, 𝑅, of its equivalent sphere is given by

(A) (𝑟1 𝑟22 )2/3

(B) 𝑟1 𝑟22

(C) (𝑟12 𝑟2 )1/3

(D) 𝑟12 𝑟2

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Geology and Geophysics (GG)

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Q.15 Which of the following sources is/are used in land seismic surveys?

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(A) Vibrosis

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(B)
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(C)
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(D) Thumper

A pebble has an average diameter of 8 mm. Its 𝜙-value on the Udden-Wentworth
Q.16
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scale is ___________ (answer in integer).

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A quartz vein in a granitic outcrop has an initial length of 20 cm. If it undergoes

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uniform stretching resulting in a longitudinal strain of 0.45, the length of the vein
post deformation is _________cm (answer in integer).

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Geology and Geophysics (GG)

Q.18 – Q.26 Carry TWO marks Each

Q.18 Which one of the following is the CORRECT pair of radioactive parent isotope and
the corresponding radiogenic daughter isotope?

(A) 87
Rb  86Sr

(B) 147
Sm  143Nd

(C) 235
U  206Pb

(D) 238
U  207Pb

Q.19 Which one of the following pairs of geophysical signatures most commonly
indicates volcanogenic massive sulphide deposits?

(A) High gravity and low resistivity

(B) Low gravity and high resistivity

(C) Low gravity and low resistivity

(D) High gravity and high resistivity

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Geology and Geophysics (GG)

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Q.20 Which one of the following is a physical weathering process?

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(A) Oxidation

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(B)
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Hydrolysis
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(C) Exfoliation

(D) Carbonation

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Q.21 .co
Which of the following statements is/are CORRECT according to the laws of
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electromagnetic induction in the Earth?
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(A) Current density in a region of finite conductivity is solenoidal

(B) Magnetic vector potential is irrotational

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(C) Magnetic field is solenoidal
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Geology and Geophysics (GG)

Q.22 Which of the following is/are REE-bearing mineral(s)?

(A) Monazite

(B) Natrolite

(C) Spodumene

(D) Gibbsite

Q.23 Which of the following pair(s) of well logs does/do NOT exhibit crossover for gas-
bearing zones in hydrocarbon reservoirs?

(A) Neutron and density

(B) Caliper and resistivity

(C) Neutron and self-potential

(D) Caliper and gamma-ray

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Geology and Geophysics (GG)

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Q.24 If the diameter of a scaled-down model of the Earth is 45 cm, then the equivalent
length on the surface of the Earth for 1 cm on the model is _____________ km
(rounded off to two decimal places).

[Use: Radius of the Earth = 6371 km]

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Q.25 The wavelength of a certain portion of the electromagnetic spectrum ranges from
2000 nm to 3000 nm. The highest frequency associated with the above portion of
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the spectrum is____________×108 MHz (rounded off to one decimal place).
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Q.26 agConsider that the upper continental crust is 10 km thick and made up of granitic
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rock having density of 2800 kg/m . The surface heat flow due to radiogenic heat
from the granitic rock having heat production value of 10−9 W/kg
is______________ mW/m2 (answer in integer).

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Geology & Geophysics - Geophysics (GG2)

PART B (SECTION 2): FOR GEOPHYSICS CANDIDATES ONLY
Q.27 – Q.44 Carry ONE mark Each

Q.27 What is the value of magnetotelluric impedance phase over a homogeneous half-
space?

(A) 0

(B) 90

(C) 45

(D) 180

Q.28 If 𝐴𝑏 and 𝐴𝑠 denote the amplitudes of the body and surface waves, respectively, at
a distance, 𝑟, from the source, then the relation between them is given by

(A) 𝐴𝑏
∝ √𝑟
𝐴𝑠

(B) 𝐴𝑏
∝𝑟
𝐴𝑠

(C) 𝐴𝑏 1
∝
𝐴𝑠 𝑟

(D) 𝐴𝑏 1
∝
𝐴𝑠 √𝑟

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Geology & Geophysics - Geophysics (GG2)

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Q.29 If τ and 𝑝 denote intercept time and slowness, respectively, in the τ − 𝑝 diagram,
then which one of the following is CORRECT for a P-wave propagating inside the
Earth?

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(A) Velocity continuously increases with depth

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(B) Velocity continuously decreases with depth

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Velocity initially increases then decreases and again increases with depth

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(D) Velocity initially decreasesathen increases and again decreases with depth

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Geology & Geophysics - Geophysics (GG2)

Q.30 If 𝑓̂(𝑡) denotes the Hilbert transform of 𝑓(𝑡), then the Hilbert transform of 𝑓̂(𝑡) is
equal to

(A) −𝑓̂(𝑡)

(B) 𝑓(𝑡)

(C) −𝑓(𝑡)

(D) 𝑑
− 𝑓(𝑡)
𝑑𝑡

Q.31 What happens to the magnetic susceptibility (𝑘) and remanent magnetization (𝐼𝑟 ),
when the molten rock undergoes rapid cooling?

(A) 𝑘 increases and 𝐼𝑟 decreases

(B) 𝑘 decreases and 𝐼𝑟 increases

(C) Both 𝑘 and 𝐼𝑟 decrease

(D) Both 𝑘 and 𝐼𝑟 increase

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Geology & Geophysics - Geophysics (GG2)

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Q.32 Between 𝐿1 and 𝐿2 norms, which one of the following is CORRECT in the
treatment of outliers in the data?

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(A)
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𝐿1 norm gives higher weightage to outliers than 𝐿2 norm
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(B) 𝐿2 norm gives higher weightage to outliers than 𝐿1 norm

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(C) a Both 𝐿 and 𝐿 norms give equal weightage to outliers
1 2

(D) 𝐿1 norm occasionally gives higher weightage to outliers than 𝐿2 norm

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Q.33 Which pairs of the following combinations of the H-, Q-, K- and A- type of
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resistivity sounding curves is/are NOT possible to generate four-layer models?
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(A) HQ and AQ

(B) KQ and QH

(C) KH and AA
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Geology & Geophysics - Geophysics (GG2)

Q.34 Which of the following is/are the correct explanation(s) for an increase in the
adiabatic temperature gradient from the lower mantle (LM) to the outer core (OC)?

(A) OC has lower specific heat capacity and higher temperature than LM

(B) OC has higher specific heat capacity and lower temperature than LM

(C) OC has lower specific heat capacity and lower temperature than LM

(D) OC has higher specific heat capacity and higher temperature than LM

Q.35 Given the Rayleigh wave velocity (𝑉𝑟 ), shear wave velocity (𝑉𝑠 ) and the P-wave
velocity (𝑉𝑝 ), which of the following relationships is/are CORRECT?

(A) 𝑉𝑟 < 𝑉𝑠 < 𝑉𝑝

(B) 𝑉𝑠 < 𝑉𝑟 < 𝑉𝑝

(C) 𝑉𝑠 < 𝑉𝑝 < 𝑉𝑟

(D) 𝑉𝑠 = 𝑉𝑟 < 𝑉𝑝

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Geology & Geophysics - Geophysics (GG2)

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Q.36 Among the given layered models, labelled as P, Q, R and S, which of the following
pairs is/are NOT possible to distinguish according to the principle of equivalence?

(P) (Q)

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(R) (S)

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(A) P, R

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(B) P, S
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(C) P, Q

(D) R, S

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Geology & Geophysics - Geophysics (GG2)

Q.37 𝑑 𝐺 𝐺12 𝐺13
Given data 𝑑 = [ 11 ] and the kernel 𝐺 = [ 11 ], which one of the
𝑑21 𝐺21 𝐺22 𝐺23
following expressions correctly represents the generalized linear inverse formula
for the model, 𝑚, satisfying 𝑑 = 𝐺𝑚?

(A) (𝐺 𝑇 𝐺)−1 𝐺 𝑇

(B) 𝐺 𝑇 (𝐺𝐺 𝑇 )−1

(C) (𝐺𝐺 𝑇 )−1 𝐺

(D) 𝐺𝐺 𝑇 𝐺 −1

Q.38 If a seismic wave is travelling along the radial direction, then which of the following
statements is/are CORRECT for Rayleigh (R) and Love (L) waves?

(A) Radial component shows the largest amplitude for both R and L waves

(B) Transverse component shows the largest and smallest amplitudes for L and R
waves, respectively

(C) Vertical component shows the largest and smallest amplitudes for L and R waves,
respectively

(D) Vertical component shows largest amplitude for R wave only

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Geology & Geophysics - Geophysics (GG2)

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Q.39 If a signal is sampled at a sampling rate of 0.2 ms, then its sampling frequency is
____________kHz.

Q.40 A P-wave of frequency 20 Hz is travelling through a non-dispersive medium with
a velocity of 5 km/s. The amplitude retained at a distance of 10 km from source is
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_____________ % (rounded off to one decimal place).
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(Use quality factor, 𝑄 = 80)
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Alaland magnetic survey was carried out along a profile length of 500 m withaan
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Q.41
spacing of 5 m over a buried ore body. The optimum width of the body
that can be best resolved is __________m (answer in integer).

Q.42 If the depth of penetration of an inducing electromagnetic wave of 1 kHz frequency
is 400 m, then the resistivity of the subsurface is ___________m (answer in
integer).

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Q.43 If 𝑭 represents the Earth’s total magnetic field corresponding to its dipole source
only, then the increase in 𝑭 from 0 to 60 N magnetic latitude is __________ %

s
(rounded off to one decimal place).
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Q.44 Considering a surface pointasource, the horizontal resolution recoverable from the
seismic data acquired using a 10 Hz seismic pulse reflected from a depth of 30 km
within the crust, with a velocity of 6.5 km/s is__________km (rounded off to two
decimal places).

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Geology & Geophysics - Geophysics (GG2)

Q.45 – Q.65 Carry TWO marks Each

Q.45 A vertical contact separating two resistive domains is shown in the figure below.
The magnitude of the discontinuity in the apparent resistivity, when the electric
field, E, is perpendicular to the strike is

(A) (𝜌1 ⁄𝜌2 )2

(B) (𝜌2 ⁄𝜌1 )2

(C) (𝜌1 ⁄𝜌2 )1/2

(D) (𝜌2 ⁄𝜌1 )1/2

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Geology & Geophysics - Geophysics (GG2)

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Q.46 If 𝑔𝐹𝐴 and 𝑔𝐵𝐴 respectively denote the free-air and Bouguer gravity anomalies over
a fully compensated mountain, then which one of the following is CORRECT in
case of Airy-isostacy?

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(A)
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𝑔𝐹𝐴 = 0, 𝑔𝐵𝐴 > 0
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(B)
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𝑔la > 0, 𝑔 = 0
𝐹𝐴 𝐵𝐴 ag
a
(C) 𝑔𝐹𝐴 > 0, 𝑔𝐵𝐴 < 0

(D) 𝑔𝐹𝐴 = 0, 𝑔𝐵𝐴 = 0

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Analytic signal, 𝐴(𝜃), for 𝑓(𝜃) = cos 𝜃.is equal to
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Q.47

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(A) 𝐴(𝜃) = − cos 𝜃

(B) 𝐴(𝜃) = − sin 𝜃

(C) 𝐴(𝜃) = 𝑒 𝑖𝜃
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c. o(D) m.co
m 𝐴(𝜃) = −𝑒 𝑖𝜃
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Geology & Geophysics - Geophysics (GG2)

Q.48 In regions of lateral conductivity contrasts, the time-independent separation
between the subsurface apparent resistivity curves of transverse electric (TE) and
transverse magnetic (TM) modes relative to each other arises mainly due to

(A) impedance phase change

(B) amplitude magnification

(C) local distortion of electric field

(D) variation in the frequency of the inducing magnetic field

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Geology & Geophysics - Geophysics (GG2)

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Q.49 How many traces will be present in a zero-offset section that is generated from the
following marine seismic survey?

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(A) 2400

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(C) 2450

(D) 2420

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Geology & Geophysics - Geophysics (GG2)

Q.50 ∆𝑇 = [∆𝑇1 , ∆𝑇2 , … . ∆𝑇19 , ∆𝑇20 ], and ∆𝑇𝑢 = [∆𝑇𝑢1 , ∆𝑇𝑢2 , … . ∆𝑇𝑢19 , ∆𝑇𝑢20 ] denote
the magnetic data observed at heights 0 km and 5 km, respectively, along a profile
of length 100 km. What is the maximum attenuation at a height of 5 km?

[use wave number in radian/km].

𝜋
(A) 𝑒 −2

(B) 𝑒 −𝜋

(C) 𝑒 −2𝜋

(D) 𝑒 −3𝜋

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Geology & Geophysics - Geophysics (GG2)

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Q.51 The given figure shows the geometry of a seismic ray path inside the Earth, with
the P-wave velocities of 10 km/s, 11 km/s and 12 km/s corresponding to the layers
L1, L2 and L3, respectively. If the angle of incidence () at L1-L2 boundary is 40,
then what is the angle of refraction at the L2-L3 boundary? (answer in nearest
integer)

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(A)
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49

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(B) 50
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(C) 53 a
(D) 55

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Geology & Geophysics - Geophysics (GG2)

Q.52 Which of the following statements about digital filters is/are CORRECT?

(A) Non-recursive filters do not have poles

(B) Recursive filters can have only poles OR both poles and zeros

(C) The order of the digital filter defines the presence of minimum number of previous
inputs only

(D) The ratio of output to input defines the transfer function of the digital filter

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Geology & Geophysics - Geophysics (GG2)

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Q.53 ∆𝐵𝑧 represents the maximum vertical magnetic anomaly along a profile due to a
horizontal cylinder with susceptibility contrast (∆k), and radius (𝑟) at a depth (𝑧)
below the Earth’s surface. Which combination(s) of ∆k, 𝑟, and 𝑧 labelled as P, Q,
R and S given below, produces/produce the same ∆𝐵𝑧 ?

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(P) ∆k=0.02, 𝑟 = 100 𝑚, and 𝑧 = 200 𝑚 (Q) ∆k=0.01, 𝑟 = 80 𝑚, and 𝑧 = 160 𝑚

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. 𝑟 = 200 𝑚, and 𝑧 = 400 𝑚 s e
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(R) ∆k=0.005, (S) ∆k=0.02, 𝑟 = 150 𝑚, and 𝑧 = 300 𝑚
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(A) P, S

(B) P, Q

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(D) Q, R

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Geology & Geophysics - Geophysics (GG2)

Q.54 If 𝑓(𝑡) = [−1, 2, 1] and 𝑔(𝑡) = [0, −1, 2] are two wavelets and 𝑓(𝜏) and 𝑔(𝜏)
represent flipped versions of 𝑓(𝑡) and 𝑔(𝑡), respectively, then which of the
following expressions is/are CORRECT?

[* and ⊗ denote convolution and cross-correlation operations, respectively]

(A) 𝑓(𝑡) ∗ 𝑔(𝑡) = 𝑓(𝑡) ⊗ 𝑔(𝑡)

(B) 𝑓(𝑡) ∗ 𝑔(𝑡) = 𝑓(𝑡) ⊗ 𝑔(𝜏)

(C) 𝑓(𝑡) ∗ 𝑔(𝑡) = 𝑓(𝜏) ⊗ 𝑔(𝑡)

(D) 𝑓(𝑡) ∗ 𝑔(𝑡) = 𝑓(𝜏) ⊗ 𝑔(𝜏)

Q.55 Which of the following assumptions is/are valid for electromagnetic induction to
happen in the Earth?

(A) Plane-wave approximation of the inducing field

(B) Displacement currents are not neglected

(C) Earth behaves as Ohmic conductor due to conservation of charge

(D) Earth does not generate electromagnetic energy, but only absorbs or dissipates it

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Geology & Geophysics - Geophysics (GG2)

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Q.56 The model regularization in a damped least square problem is/are used to

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(A) introduce additional constraints to the ill-posed problems

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(D) control the trade-off between the misfit and the model variance

The vector field (𝑭) for a region is described by 𝑭 = 𝑎𝑟 𝑛 𝑟̂ (𝑟 ≠ 0), where 𝑎 is a
Q.57
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non-zero constant and 𝑟 is the radial distance from the source. For what value(s) of
𝑛, 𝑭 becomes both solenoidal and irrotational?
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(A) 2

(B) -2

(C) 1
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Geology & Geophysics - Geophysics (GG2)

Q.58 The maximum strain for the plane wave at 𝑡 = 0, having a wavelength of 16 km
and unit amplitude, travelling along the X-direction, as shown in the figure,
is _______(rounded off to three decimal places).

Q.59 A causal recursive filter is given by 𝑦𝑛 = 𝑥𝑛 − 2𝑥𝑛−1 + 3𝑦𝑛−1 . If the input values,
𝑥0 , 𝑥1 and 𝑥2 are 1.2, −0.8 and 2.3, respectively, the output, 𝑦2 , of the filter is
__________ (rounded off to one decimal place).

Q.60 If C1 & C2 and P1 & P2 are the pairs of current and potential electrodes in the
Wenner (W) and Dipole-Dipole (DD) array configurations as shown in the figure
below, then the fraction of the geometric factor for DD array that will be equal to
half of that of W array is _______________ (rounded off to three decimal places).

(Use n = 1 in DD array)

Q.61 A scintillometer records 300 counts per second (cps) in a radiometric survey. If the
background radiation and dead-time of the instrument are 100 cps, and 250s,
respectively, then the true net count rate is _______ cps (rounded off to two
decimals).

Q.62 Gamma-ray (GR) log values for clean sandstone and shale are 15 API and 115 API,
respectively. If GR records 35 API for shaly-sandstone, then the GR index is
_____________ (rounded off to one decimal place).

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Q.63 If the inclination of the remanent magnetic field of a 140 million years old crustal
block at equator is 50, then its drift-rate is ______________cm/yr (rounded off to
two decimal places).

[use 1 = 111 km]

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Q.64
at a distance of 1 km away from the seismic source and a geophone is suspended
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inside the well at a depth of 800 m as shown in the figure below. The travel time of
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l as
the primary reflected wave from a horizontal reflector located at a depth of 2 km is
ag
ag ___________s (rounded off to three decimal places).

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Geology & Geophysics - Geophysics (GG2)

Q.65 The figure below shows Bouguer gravity anomaly values (in mGal) at a grid interval
of 1 km. The second vertical derivative at P is _________mGal/km2 (rounded off
to two decimals).

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