SIO182. Environmental and Exploration Geophysics (4 units) 

Catalog: Theory and practice of nonseismic geophysics for groundwater, environmental, and exploration purposes. Lectures are supplemented by collection of gravity, magnetic, and resistivity data; data analysis; and report writing. Includes an introduction to Matlab as a tool for geophysical data interpretation.

Instructor: Steven Constable, Scripps Institution of Oceanography.

Consider signing up for SAGE - Summer of Applied Geophysics Experience.

Winter 2025 Dairy and Calendar:

7 January: First day of class - notes for Introduction, Gravity, and Matlab updated and posted.
16 January: (Thursday). Hold this date for gravity data collection - we meet in the IGPP classroom.
17 January: Free money! Apply for an SEG scholarship: See this email
6 February: Magnetics on the Beach, weather permitting. Meet in the Munk classroom, or go directly to the base of the pier if you are running late.
11 February: Magnetics data posted.
27 February: Resistivity on the beach.
8-9 March: Field trip to Borrego Springs. Meet in the service yard outside my lab at 9 am on the 8th.

Homework Assignments:

A few (useful?) notes on doing assignments.
Assignment 1. Given 9 January, due 16 January
Assignment 2. Given 21 January, due 28 January
Assignment 3. Given 28 January, due 4 February
Assignment 4. Given 4 February, due 11 February
Assignment 5. Given 11 February, due 18 February
Assignment 6. Given 18 February, due 25 February

Notes:

The following are the course notes as PDF files:
Introductory material, synopsis, and syllabus.
Gravity
Notes on gravity data reduction
Slides from gravity class.
Magnetics
Slides from magnetics class.
Electrical Methods
Notes on magnetic data reduction
Extracts from "The Geophysics of the Elura Ore Body"
Slide deck on ground penetrating radar
Electromagnetic Methods
Slides for induction and MT method.
Introductory seismic notes (courtesy Alistiar Harding)
Notes on resistivity data reduction

The following are the Matlab notes as PDF files (courtesy Alistair Harding):
Introduction
Index Manipulation
Functions

Slides and notes from Ross' classes:
sio182_ReflectionSeismology1_2025
sio182_ReflectionSeismology2_2025
notes Ch4
notes Ch5

MATLAB routines:

plot_mtsoledad_map.m Plots a topographic map of our gravity project area with faults, etc. You will need to down-load the following files (and the 2025 gravity data set):
ljtopo1.mat
coastline.latlong
ljfaults1.latlong
ljfaults2.latlong
ljroads.latlong
ljbenchmarks.latlong

PlotGrav.m Plots the processed gravity data (you need to supply the processed data!).
fault.m Computes the gravity anomaly due to a buried fault
mdipole.m Computes a dipole magnetic anomaly (now with 4*pi term!)
SFilt.m Computes DC apparent resistivity curves over a layered earth
MT1d.m Computes MT apparent resistivity and phase curves over a layered earth

Field Data:

gravity2025.txt The accumulated gravity data for this class as of 2025
Nettleton.txt Data for Nettleton's correction
FaultData.txt Average gravity values over Rose Canyon Fault (kilometers, milligals)
mag2007.mat Magnetic data from 2007.
mag2008.mat Magnetic data from 2008.
mag2010.mat Magnetic data from 2010.
mag2012.mat Magnetic data from 2012.
mag2013.mat Magnetic data from 2013.
mag2015.mat Magnetic data from 2015.
mag2016.mat Magnetic data from 2016.
mag2017.mat Magnetic data from 2017.
mag2018.mat Magnetic data from 2018.
mag2019.mat Magnetic data from 2019.
mag2022.mat Magnetic data from 2022.
mag2024.mat Magnetic data from 2024.
mag2025.mat Magnetic data from 2025.

res2025.txt The resistivity data collected in 2025
res2024.txt The resistivity data collected in 2024
CMPline33.pdf Common midpoint RADAR line 2024
line32.pdf Willow Road RADAR line 2024
res2022.txt The resistivity data collected in 2022
CMPline29.pdf Common midpoint RADAR line 2022
line28.pdf Willow Road RADAR line 2022

Useful links:
USGS Gravity map of USA.
NOAA's IGRF calculator
EMAG2 Map of Magnetic Anomalies Worldwide

Nice maps:
Tect_map.pdf
Geol_map.pdf
Mag_map.pdf