APPLIED GEOPHYSICS

Single discipline educational activity

Course Sheet

Course code:

GE106

Academic Year of enrolment:

2019

Year of supply:

2019/2020

Type of Course:

Characterising

Degree:

Course of 2nd Cycle Degree in GEOLOGICAL SCIENCES AND TECHNOLOGIES OF EARTH AND PLANETS

Disciplinary Sector:

Applied Geophysics

Language:

Italian

Location:

CHIETI

Credits:

Programme Year:

Professor and Collaborators:

MANCINELLI PAOLO

Cycle:

Second semester

Hours of classroom activity:

Individual study hours:

Prerequisites:

Basic knowledge of physics, trigonometry, magnetic and gravity potential fields, thermal field of the Earth.

Objectives

The course aims to provide to the students the fundamental knowledge to produce and understand the main geophysical methods to investigate and characterize the sub-surface using active and passive methods such seismic profiles, electric and electromagnetic methods, potential fields anomalies analysis and thermal field analysis at all scales.

Contents

This course deals with the main geophysical methods to investigate sub-surface.
We will see active prospection methods (e.g. seismic refraction, reflection) and passive methods (e.g. gravity and magnetic anomalies, heat flow) that are used for the characterization at the crustal scale for exploration or research purposes.
We will also see local-scale methods (e.g. MASW, Electrical methods, GPR) that are used for the characterization of construction site and near surface geophysics.

Extended Syllabus

• Basic concepts on waves, time-domain Vs frequency domain. What is an anomaly, what is noise, SNR
• Seismic waves: volume and surface waves
• Wavefront and raypath, acoustic impedence, diffraction and convloution.
• Time-space relations for direct, refracted and reflected waves in horizontal and parallel strata
• Time-space relations for direct, refracted and reflected waves in inclined stratification.
• Refraction seismic, Snell law, critical refraction, reflection coefficient, limitations of the refraction method
• Reflection seismic, Common Shot Gathers, Common Mid Point.
• Precautions to perform a proper seismic acquisition.
• Fundamentals of seismic processing (NMO, Stacking, deconvolution, migration, depth conversion).
• Seismic velocities of rocks, methods for determination and importance of the velocity model.
• Surface waves, dispersion, main characteristics of the surface waves and seismostratigraphic characterization of construction sites as defined in the NTC2018 law.
• Surface waves methods: MASW, HVSR. Main characteristics, limitations and advantages.
• Electrical methods: resistivity of rocks, electrodes configuration for resistivity measurements, apparent res. Vs real res. ERT inversions
• Basic notions about spontaneous potential methods, induced polarization, TEM and TDEM methods and magnetotelluric methods.
• Ground Penetrating Radar (GPR), relation between GPR pulse velocity and EM properties of materials, resolution vs penetrationn of GPR signal as a function of antenna’s frequency, limitations due to high-conductivity materials, range of applications of GPR instruments.
• Magnetic anomalies, magnetization and induced field, ACurie temperature -> Curie depth, magnetic susceptibility, paleomagnetism.
• Analysis of anomaly maps: intensity and wavelength of anomalies.
• Gravity anomalies: gravity data corrections, density of rocks, principles for interpretation of gravity anomalies.
• Anomalies filtering, forward modeling, inverse modeling.
• 4D geophysics: its significance, applications and capabilities.
• Laboratory exercise: 2D and 3D integrated modeling of geological and geophysical data for the crustal-scale investigation.

Recommended Bibliography

• An Introduction to Applied and Environmental Geophysics – J. M. Reynolds – Wiley-Blackwell
• An introduction to geophysical exploration – P. Kearey et al – Wiley-Blackwell
• Applied geophysics – W. M. Telford et al – Cambridge University press

Teaching Methods

Frontal lectures and exercises

Evaluation methods

Verification of learning:

Learning of the concepts discussed during the lessons will be evaluated with an oral exam after the course is completed. The exam will involve only the themes discussed in the lessons. The questions that will be asked will address the entire program and deal with the most important concepts discussed during lessons and eventual exercises.

Contacts/More Information

Slides showed during the lessons will be provided to the students.

Università degli Studi
"G. d'Annunzio"

Chieti - Pescara

Aree