Combined Geo-Scientist 2021 Geo-Physics Paper I Question Paper PDF

Central Government Jobs Other Jobs 2021

  • Year 2021
  • Conducted By UPSC
  • Questions 10
  • Maximum Marks 200
  • Duration Three Hours
  • Languages English

Exam Details

Detail Information
Examination Combined Geo-Scientist (Main) Examination
Year 2021
Conducting Body UPSC
Paper GEO-PHYSICS Paper - I
Subject Geo-Physics
Duration Three Hours
Maximum Marks 200
Number of Questions 10
Question Type Descriptive / Subjective

This is the official question paper for the Combined Geo-Scientist (Main) Examination, 2021, specifically for Geo-Physics Paper I. Conducted by UPSC, this paper carries a maximum of 200 marks and allows three hours for completion. It is designed to assess candidates' in-depth knowledge of Geo-Physics. Aspirants preparing for the Geo-Scientist exam will find this paper invaluable for understanding the exam pattern, difficulty level, and the types of questions asked, particularly in the descriptive format. Studying previous year papers like this one is crucial for effective preparation and improving performance.

Major Topics Covered

  • Geophysics
  • Earth's Surface
  • Latitude and Longitude
  • Magnetization
  • Basalt
  • Seismic Energy
  • Earthquake Magnitude
  • Inverse Problem
  • Tikhonov Regularization
  • Isostasy
  • Pratt's Hypothesis
  • Airy's Hypothesis
  • Heat Conduction
  • Earth's Interior
  • Seismic Waves
  • Seismic Refraction Survey
  • Crustal Structure

Why This Paper is Important

  • Useful for Combined Geo-Scientist (Main) Examinatio preparation
  • Helps understand the latest exam pattern
  • Useful for practice and self-assessment
  • Covers frequently asked General Studies topics
  • Helpful for analysing question trends

Related Resources

  • Combined Geo-Scientist (Main) Examination, 2021 - Geo-Physics Paper II
  • Combined Geo-Scientist (Main) Examination, 2020 - Geo-Physics Paper I
  • Combined Geo-Scientist (Preliminary) Examination, 2021 - General Studies Paper
  • Combined Geo-Scientist (Preliminary) Examination, 2021 - Geo-Physics Paper
  • Combined Geo-Scientist (Main) Examination, 2021 - Geo-Physics Paper I Answer Key
  • Combined Geo-Scientist (Main) Examination Syllabus
  • Geo-Physics Syllabus for UPSC Exams
  • UPSC Main Exam Syllabus

Instructions

  • There are TEN questions divided under TWO sections.
  • Candidate has to attempt SIX questions in all.
  • Out of the remaining EIGHT questions, FOUR questions are to be attempted choosing TWO from each section.
  • The number of marks carried by a question / part is indicated against it.
  • Neat sketches may be drawn to illustrate answers, wherever required.
  • These shall be drawn in the space provided for answering the question itself.
  • Unless otherwise mentioned, symbols and notations have their usual standard meanings.
  • Assume suitable data, if necessary, and indicate the same clearly.
  • Attempts of questions shall be counted in sequential order.
  • Unless struck off, attempt of a question shall be counted even if attempted partly.
  • Any page or portion of the page left blank in the Question-cum-Answer Booklet must be clearly struck off.
  • Answers must be written in ENGLISH only.

Questions (page 2)

Section A

Q1.

(a) What is the difference in the length, in kilometers, at the Earth's surface, between a degree of latitude at equator and at the pole?

(b) The angle of inclination and declination of a remanent magnetization of basalt are observed as 45\circ and 60\circ, respectively, at present location of 30\circN, 25\circE. Calculate the magnetic latitude of this site at the time of magnetization of basalt. Find out the latitude and longitude of the palaeomagnetic pole.

(c) Calculate the amount of increase in seismic energy released from the earthquake for the following:
(i) When surface-wave magnitude increases from 5 to 6; 6 to 7 and 7 to 8.
(ii) When body-wave magnitude increases from 5 to 6; 6 to 7 and 7 to 8.

(d) Explain the concept of Tikhonov regularization in context to the inverse problem, and explain what is an L-curve solution.

Section A

Q2.

(a) Calculate the depth and density beneath a 5-km-high Himalayan mountain chain in isostatic equilibrium with a 35-km-thick continental crust of density 2.8 g/cc and a mantle of density 3.3 g/cc by using the hypotheses of (i) Pratt, and (ii) Airy.

(b) Derive heat-conduction equations for an Earth model having low temperature at upper surface as compared to high temperature at lower surface.

(c) How do density, gravity and pressure vary radially in the interior of the Earth? Derive equations and discuss them with suitable figures related to variations of these physical properties.

Section A

Q3.

(a) How are seismic waves attenuated during propagation from the source?

(b) What is earthquake magnitude? Describe body-wave, surface-wave and moment magnitude with the help of suitable equations.

(c) The first-arrival time-distance data from a seismic refraction survey were plotted and the best line fits have the slope of 0.22222 s km^{-1}, 0.164474 s km^{-1}, 0.153846 s km^{-1} and 0.119760 s km^{-1}, respectively. Intercept times were observed to be 1.00 s, 1.90 s and 8.70 s, respectively, from the plot. Compute the velocity-depth structure and thickness of the crustal layer.

Question paper preview

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Combined Geo-Scientist Main 2021 Geo-Physics Paper I question paper page 1 instructions and header scan PDF download
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Frequently asked questions

What is the name of the examination?

The examination is the Combined Geo-Scientist (Main) Examination, 2021.

Which paper is this question paper for?

This question paper is for Geo-Physics Paper - I.

Who conducts the Combined Geo-Scientist Examination?

The examination is conducted by UPSC (Union Public Service Commission).

What is the maximum number of marks for Geo-Physics Paper - I?

The maximum marks for Geo-Physics Paper - I is 200.

What is the time allowed to complete the paper?

The time allowed to complete the paper is Three Hours.

What is the question paper code?

The question paper code is SDT-F-GPH.

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