Syllabus /

# Mains Geophysics Paper-II

### Stage-II (Descriptive Type)

Geophysics : Paper-II

PART-A

**A1. Potential Field (Gravity and Magnetic) Methods:**

Geophysical potential fields, Inverse square law, Principles of Gravity and Magnetic methods, Global gravity anomalies, Newtonian and logarithmic potential, Laplace’s equations for potential field.

Green’s Function, Concept of gravity anomaly, Rock densities, factors controlling rock densities, determination of density, Earth’s main magnetic field, origin, diurnal and secular variations of the

field, Geomagnetic elements, intensity of magnetization and induction, magnetic potential and its relation to field, units of measurement, interrelationship between different components of magnetic

fields, Poisson’s relation, Magnetic susceptibility, factors controlling susceptibility. Magnetic Mineralogy: Hysteresis, rock magnetism, natural, and remnant magnetization, demagnetization effects. Principles of Gravity and Magnetic instruments, Plan of conducting gravity and magnetic surveys, Gravity and Magnetic data reduction, Gravity bases, International Gravity formula, IGRF

corrections. Concept of regional and residual anomalies and various methods of their separation, Edge Enhancement Techniques (Derivatives, Continuation, Analytical Signal, Reduced to Pole and

Euler Deconvolution), ambiguity in potential field interpretation, Factors affecting magnetic anomalies, Application of gravity and magnetics in geodynamic, mineral exploration and

environmental studies. Qualitative interpretation, Interpretation of gravity and magnetic anomalies due to different geometry shaped bodies and modeling.

**A2. Electrical and Electromagnetic methods:**

Electrical properties of rocks and minerals, concepts and assumptions of horizontally stratified earth, anisotropy and its effects on electrical fields, geoelectric and geological sections, D.C Resistivity method. Concept of natural electric field, various electrode configurations, Profiling and Sounding (VES). Tpes of Sounding curves, Equivalence and Suppression, Concept of Electrical Resistivity Tomography (ERT). SP Method:, Origin of SP, application of SP surveys. Induced Polarization (IP) Method: Origin of IP, Membrane and Electrode polarization, time and frequency domains of measurement, chargeability, percent frequency effect and metal factor, Application of IP surveys for mineral exploration. Electromagnetic methods, Passive and Active source methods, Diffusion equation, wave equation and damped wave equation used in EM method, boundary conditions, skin depth, depth of investigation and depth of penetration, amplitude and phase relations, real and imaginary components, elliptical polarization, Principles of EM prospecting,various EM methods: Dip angle, Turam, moving source-receiver methods-horizontal loop (Slingram), AFMAG, and VLF.. Principles of Time Domain EM: INPUT method. EM Profiling and sounding, Interpretation of EM anomalies. Principle of EM scale modeling. Magnetotelluric methods: Origin and characteristics of MT fields, Instrumentation, Transverse Electric and Transverse Magnetic Modes, Static Shift. Dimensionality and Directionality analysis. Field Layout and interpretation of MT data and its applications. Principles of Ground Penetrating Radar (GPR).

**A3. Seismic Prospecting:**

Basic principles of seismic methods, Various factors affecting seismic velocities in rocks, Reflection, refraction and Energy partitioning at an interface, Geometrical spreading, Reflection and refraction of wave phenomena in a layered and dipping media. Seismic absorption and anisotropy, Multi channel seismic (CDP) data acquisition (2D and 3D), sources of energy, Geophones, geometry of arrays, different spread geometry, Instrumentation, digital recording. Different types of multiples, Travel time curves, corrections, Interpretation of data, bright spot, low velocity layer, Data processing, static and dynamic (NMO and DMO) corrections, shot-receiver gather, foldage, multiplexing and demultiplexing. Dix’s equation, Velocities: Interval, Average and RMS, Seismic resolution and Fresnel Zone, Velocity analysis and Migration techniques, Seismic Interpretation, Time and Depth Section, Fundamentals of VSP method, High Resolution Seismic Surveys (HRSS).

**A4. Borehole Geophysics:**

Objectives of well logging, concepts of borehole geophysics, borehole conditions, properties of reservoir rock formations, formation parameters and their relationships-formation factor, porosity,

permeability, formation water resistivity, water saturation, irreducible water saturation, hydrocarbon saturation, residual hydrocarbon saturation; Arhcie’s and Humble’s equations; principles,

instrumentations, operational procedures and interpretations of various geophysical logs: SP, resistivity and micro resistivity, gamma ray, neutron, sonic, temperature, caliper and directional

logs. Production logging, overlay and cross-plots of well-log data, determination of formation lithology, porosity, permeability and oil-water saturation, sub-surface correlation and mapping,

delineation of fractures; application of well-logging in hydrocarbon, groundwater, coal, metallic and non-metallic mineral exploration.

### PART-B

**B1. Classical Mechanics**

Inertial and non-inertial frames, Newton’s laws; Pseudo forces; Central force motion; Two-body collisions, Scattering in laboratory and centre-of-mass frames; Rigid body dynamics, Moment of

inertia, Variational principle, Lagrangian and Hamiltonian formalisms and equations of motion; Poisson brackets and canonical transformations; Symmetry, Invariance and conservation laws,

Cyclic coordinates; Periodic motion, Small oscillations and normal modes; Special theory of relativity, Lorentz transformations, Relativistic kinematics and mass-energy equivalence.

**B2. Thermodynamics and Statistical Physics**

Laws of thermodynamics and their significance; Thermodynamic potentials, Maxwell relations; Chemical potential, Phase equilibria; Phase space, Micro- and macro- states; Micro canonical,

canonical and grand-canonical ensembles and partition functions; Free Energy and connection with thermodynamic quantities; First and second order phase transitions; Maxwell-Boltzmann

distribution, Quantum statistics, Ideal Fermi and Bose gases; Principle of detailed balance; Blackbody radiation and Planck’s distribution law; Bose-Einstein condensation; Random walk and

Brownian motion; Diffusion equation.

**B3. Atomic and Molecular Physics and Characterization of materials**

Quantum states of an electron in an atom; Electron spin; Stern-Gerlach experiment; Spectrum of Hydrogen, Helium and alkali atoms; Relativistic corrections for energy levels of hydrogen; Hyperfine structure and isotopic shift; Width of spectral lines; LS and JJ coupling; Zeeman, Paschen Back and Stark effects; Rotational, vibrational, electronic, and Raman spectra of diatomic molecules; FrankCondon principle; Thermal and optical properties of materials, Study of microstructure using SEM, Study of crystal structure using TEM, Resonance methods: Spin and applied magnetic field, Larmor precession, relaxation times – spin-spin relaxation, Spin-lattice relaxation, Electron spin resonance, g factor, Nuclear Magnetic resonance, line width, Motional narrowing, Hyperfine splitting; Nuclear Gamma Resonance: Principles of Mössbauer Spectroscopy, Line width, Resonance absorption, Isomer Shift, Quadrupole splitting.

**B4. Nuclear and Particle Physics**

Basic nuclear properties: size, shape, charge distribution, spin and parity; Binding energy, Packing fraction, Semi-empirical mass formula; Liquid drop model; Fission and fusion, Nuclear reactor; Line of stability, Characteristics of the nuclear forces, Nucleon-nucleon potential; Charge-independence and charge-symmetry of nuclear forces; Isospin; Deuteron problem; Evidence of shell structure, Single-particle shell model and, its validity and limitations; Elementary ideas of alpha, beta and gamma decays and their selection rules; Nuclear reactions, reaction mechanisms, compound nuclei and direct reactions; Classification of fundamental forces; Elementary particles (quarks, baryons, mesons, leptons); Spin and parity assignments, strangeness; Gell Mann-Nishijima formula; C, P and T invariance and applications of symmetry arguments to particle reactions, Parity non-conservation in weak interaction; Relativistic kinematics.

Combined Geo Scientist exam application Fee – Rs. 200/-

Age Limits 21-32 years-Relaxation-Educational Qualification-M.Sc-

Chemist, Group A – 15 Vacancies-Hydrogeology-16 Vacancies-Geophysics-06 Vacancies

All over India 19 Centres-Bhopal, Chennai, Delhi, Dispur,Cuttack…

Download e-Admit Card -three weeks before the commencement of the Examination.

Paper-I : General Studies-100 Marks-Paper-II : Core Subject-300 Marks-Main Exam-600 Marks

CGSE Preliminary Exam Date – 21st February, 2021 Main Exam Date – 17th & 18th July, 2021

Online Applications can be filled up to 27th October, 2020 Application Form containing two stages viz.Part-I and Part-II contact UPSC’s Facilitation Counter Telephone No. 011-23385271

Stage-I : 400 Marks-Stage-II : 600 Marks-Stage-III: 200 Marks

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