GLY 624

GLY 624
Advanced structural geology
Course description: This is a 3 credit course on the theory, principles and application of
structural geology. Prerequisite: GLY 420G or equivalent. The textbook Analysis of
Geologic Structures by Price and Cosgrove is optional but will be referred to during the
course. Other texts will be referred to and these are on reserve in the Pirtle Library:; An
outline of structural geology by Hobbs Means and Williams; Stress and Strain by Means;
Principles of structural geology by Suppe; The Geology of Earthquakes by Yeats, Sieh
and Allen.
Lecture: TR : 12:30- 1:45 PM
Instructor: Kieran O’Hara
Office: 111/112 Slone
office hrs: TR 2-3
Course organization: Early in the semester there will be 2 lectures per week. Several
take-home assignments will also be given during this part of the course. Later on in the
semester, more time will be spent on student presentations in class, based on written
assignments and on a field project at Camp Nelson.
Course objectives: My main interest in structural geology is in understanding geologic
and petrologic processes involved in the upper and lower crust, rather than description of
geologic structures or studying specific field areas because they exist. The problem to be
solved should determine the field area, rather than the converse. This course will
therefore emphasize mechanisms and processes with the goal of understanding
fundamental principles.
Grade: midterm test: 20 %
final test: 20 %
take-home assignments 20%
term paper (including oral presentation) 20%
field project (including oral presentation) 20%
Tentative lecture topics
Practical assignments
models of continental crust
brittle behavior
plastic behavior
fault mechanics
geology of earthquakes
small scale structures
fluid-rock interaction
strain measurement
shear zone strain
strength of crust
fluid inclusions
This morning I took out a coma and this afternoon I put it back in- Oscar Wilde
Mini-paper (due during semester)
The writing assignments consist of one mini-paper and a paper to accompany the field
project, both of which will be the basis of two 15 minute in-class presentations by
students. The class as a whole will have input on the quality of the in-class oral
presentations, which will be furnished to the presenter, and will be part of the course
grade. I will edit and comment on a first draft of the mini-paper and ask that you revise
accordingly (due dates for first draft will be set later). Final drafts of the mini-paper and
field project are due before the final exam.
All writing assignments will be graded with the following criteria in mind: clarity
and organization, scientific content (e.g. supporting evidence, clarity and relevance of
diagrams; adequate and accessible references), lack of repetition in text, grammar,
spelling etc. Papers which make interesting syntheses or draw new conclusions or identify
new problems/ avenues of research will be ranked higher. Ideas for suitable topics can be
found in recent abstract meetings (e.g. EOS or GSA). These topics may be related to your
thesis proposal, but should not be a repetition of that proposal. My research interests
combine petrology, geochemistry and structural geology, so that any topics broadly within
these areas are fine. The format of the mini-paper should be that of a current Geology
paper- with an abstract, introduction, main body and conclusions, figures, and references.
Papers should be approximately 10 pages in length, double spaced, excluding figures.
Field Project (map and paper due end of term)
Camp Nelson. This outcrop is already familiar to some of you:- Camp Nelson on rte 27
south of Nicholasville. Here the Kentucky river fault is exposed, together with a kink
fold, fault breccia, numerous types of faults of different orientations, veins, joints,
slickenlines, minor Pb-fluorite mineralization et cetra. The structural history of this
outcrop is unclear and still remains to be determined. Interesting questions are 1) was this
outcrop the site of seismicity or can the structural features be explained by non-seismic
processes, 2) is the major fault related to the kink fold, and if so how; if not, what is their
relative age?. Can the features of the outcrop be explained by a single stress regime (i.e.
strike slip, normal, thrust etc).?
The first and basic part of the field project is to produce a detailed geologic map
of the outcrop at an appropriate scale. The second part is to deduce and explain the
kinematic and structural history of the area (also one of the in-class presentations). The
geologic map should therefore be accompanied by text explaining your deductions on the
history of the outcrop, as far as possible, similar in extent and detail to the mini-paper text
described above. Although the field project is due at the end of the semester, an oral
presentation based on this project will be made before the semester ends, and the dates of
these presentations will be scheduled.