A course note to undergraduates of major Geology/Geophysics And Diploma students Prof. Dr. Mohamed Gobashy ﷴ ﻣﺼﻄﻔﻰ ﻏﺒﺎﺷﻲ.د.أ 3/18/2018 Prof. M Gobashy -- spring 2018 1 Introduction to Geophysics 3/18/2018 Prof. M Gobashy -- spring 2018 2 What is Geophysics? A Question with Many Answers Geophysics is: The subsurface site characterization of the geology, geological structure, groundwater, contamination, and human artefacts beneath the Earth's surface, based on the lateral and vertical mapping of physical property variations that are remotely sensed using noninvasive technologies. Many of these technologies are traditionally used for exploration of economic materials such as groundwater, metals, and hydrocarbons. Geophysics is: The non-invasive investigation of subsurface conditions in the Earth through measuring, analysing and interpreting physical fields at the surface. Some studies are used to determine what is directly below the surface (the upper meter or so); other investigations extend to depths of 10's of meters or more. 3/18/2018 Prof. M Gobashy -- spring 2018 Wordon gravity meter in action 3 Both of these definitions have a common component, namely that geophysics represents a class of subsurface investigations that are non-invasive (i.e. that do not require excavation or direct access to the subsurface). The exceptions are borehole geophysical methods that expand the use of holes already drilled to access the subsurface on a very localized basis. Two important issues in Geophysics: Spectrum 3/18/2018 Prof. M Gobashy -- spring 2018 Scale 4 Spectrum 3/18/2018 Prof. M Gobashy -- spring 2018 5 Scale Astro geophysics اﻟﻘﺸﺮه Marine geophysics اﻟﻮﺷﺎح اﻟﻠﺐ 3/18/2018 Prof. M Gobashy -- spring 2018 Solid earth geophysics 6 Airborne Gravity methods Economic geology geochemistry Ship born Solid earth geophysics Earth sciences Borehole Astro geophysics GEOPHYSICS Soil sciences Engeneering geology Structural geology Oceanography Land Electric methods Palaeontology hydrology Magnetic methods Seismic methods Satellite Electromagnetics Marine geophysics Georadar Geophysical Well Logging Seismology Radioactive methods 3/18/2018 Prof. M Gobashy -- spring 2018 7 What are the Types of Problems Addressed? 1. Environmental and engineering problems Infrastructure (highways and bridges) Groundwater (exploration and contaminant mapping) Geohazards (earthquake mitigation and collapse structure mapping) Urban (utility mapping, underground storage tank location) Geologic Mapping Archaeology Forensics (i.e., illegal burials, etc.) Civil Engineering / Non-Destructive Testing (NDT) So-called "Brownfield" and Landfill Investigations Unexploded Ordnance (UXO detection and characterization) Dam Safety. 2. In oil exploration industry, exploration for hydrocarbons 3/18/2018 Prof. M Gobashy -- spring 2018 8 3. Hydrogeological studies and search for aquifers and underground water 4. Regional tectonics and continental plate studies and plate boundaries 5. Oceanography 6. Study the Figure of the earth ex. Sea surface topography Prof. M Gobashy -- spring 2018 3/18/2018 9 3/18/2018 Prof. M Gobashy -- spring 2018 10 3/18/2018 Prof. M Gobashy -- spring 2018 11 Prof. M Gobashy -- spring 2018 3/18/2018 12 3/18/2018 Prof. M Gobashy -- spring 2018 13 3/18/2018 Prof. M Gobashy -- spring 2018 14 3/18/2018 Prof. M Gobashy -- spring 2018 15 3/18/2018 Prof. M Gobashy -- spring 2018 16 Prof. M Gobashy -- spring 2018 17 3/18/2018 3/18/2018 Prof. M Gobashy -- spring 2018 18 Prof. M Gobashy -- spring 2018 3/18/2018 19 Exploring deep earth structures 3/18/2018 Prof. M Gobashy -- spring 2018 20 Geophysicists can work at any conditions 3/18/2018 Prof. M Gobashy -- spring 2018 21 Magnetic Gradiometry 3/18/2018 Prof. M Gobashy -- spring 2018 22 GPR surveys 3/18/2018 Prof. M Gobashy -- spring 2018 23 3/18/2018 Prof. M Gobashy -- spring 2018 24 INTERPRETATION 3/18/2018 Prof. M Gobashy -- spring 2018 25 The satellite archaeological survey of Egypt 3/18/2018 Prof. M Gobashy -- spring 2018 26 Gravity & Magnetic 3/18/2018 Prof. M Gobashy -- spring 2018 27
