Precambrian Geology EAS Fall

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					          Precambrian Geology EAS432
                    Fall 2010

Instructor:   Larry Heaman
Office:       4-18 Earth Science Building
Phone:        492-2778
E-mail:       larry.heaman
Lecture Room: ESB1-31 (Tuesday 6-9 pm)

Grade Evaluation:
                             WEIGHTING      DATE
Midterm (2 hours)             20%           Oct. 26
Seminar Presentation          20%           TBA
Seminar Participation         10%
Term Paper                    50%           Dec. 8 (5pm)
             Course Objectives
The Precambrian time period encompasses more than 85% of Earth’s
geological history and represents a very important period during which
continents, atmospheres, oceans and life itself formed and evolved.
Many features of Earth processes that operate today were established
in the Precambrian so it is instructive for earth scientists to become
familiar with the Precambrian geological record.

The primary goal of this course is to provide an overview of
Precambrian geology worldwide and to investigate Earth’s early
evolution but with a definite emphasis on North America.

The lecture portion of the course will have a bias toward presenting a
big picture overview of Precambrian Earth evolution calling on
geological, structural, geophysical, geochemical and isotopic aspects
of the geological record. Of great importance is the nature and absolute
timing of Precambrian geological events as accurate radiometric ages
underpin nearly all tectonic interpretations.
                Course Format
Approximately 50% of the course will consist of lectures
given by the instructor (first half of term), which emphasize
key aspects of Precambrian geology on a global or
continent-wide scale.

The remaining 50% of the course will comprise student
seminar presentations and a written term paper that
describes in detail the geological evolution of a specific
Precambrian crustal province. Throughout the course
students should keep track of geological information
preserved in the Precambrian record that is consistent with
modern plate tectonic concepts and those features that do

The midterm examination in the course will cover material
given in the lectures and the content in the Hoffman (1989)
  Tentative Lecture Schedule
Week   Topic
1.     Introduction to Precambrian geology
1.     Review of isotope geology relevant to the Precambrian
1.     Clues to Earth history from lunar and meteorite samples
2.     The early Earth (4.6-4.2 Ga)
2.     The oldest rocks and minerals preserved on Earth (4.2-3.8 Ga)
3.     Processes responsible for the formation of continental crust
3.     Archean cratons – origin of granite/greenstone belts
4.     Archean/Proterozoic boundary
4.     Earth’s early atmosphere/hydrosphere
4.     Banded Iron Formations
5.     Proterozoic - general characteristics
5.     Paleoproterozoic orogenic belts
5.     Mesoproterozoic anorogenic magmatism
6.     Neoproterozoic assembly and breakup of a supercontinent
6.     Neoproterozoic Snowball Earth Hypotheses
12.    Overview of the Precambrian geology of North America
           Required Textbook
There is no required textbook for the course. However,
the references provided are good starting points for
researching a particular topic in more detail. Another
good starting point for researching a Precambrian terrain
is to scan the recent periodicals, especially the journal
Precambrian Research. If you are having difficulty
getting started you should see me as soon as possible.

Hoffman, P.F. (1989) Precambrian geology and tectonic history of North
America. In: The Geology of North America - An overview. (Bally, A.W.
and Palmer, A.R. eds.). Geological Society of America
Each student will be given one major Precambrian crustal province and will
be responsible for preparing a detailed synthesis of the geological evolution
of that province.

The term paper should be about 3000-5000 words (about 8-10 typed double-
spaced pages; including references – this does not include figures or
tables). The term paper should follow the general format of articles published
in scientific journals, such as the Canadian Journal of Earth Sciences or
Precambrian Research, and be fully referenced.

The term paper needs to be well researched with a conscientious effort to
find relevant material on the topic using the internet and library search
engines. You will need to use all relevant literature that is available,
including government geological reports, special publications and journal
articles. The paper is to be a summary written in your own words and not at
collection of quotations from other authors. The term paper will be assessed
on the following merits, 1) the thoroughness of the research, 2) the accuracy
of the scientific content, 3) the level of organization, 4) the clarity and
conciseness of the writing and presentation and 5) innovative ideas that may
add to our understanding of the tectonic evolution of the province.
                   Term Paper
A section on “Future Research Directions“ that outlines
outstanding problems that still exist and some suggestions for
ways to address/solve these problems must be included.

A Geological Compilation Chart prepared at a scale of 1 cm =
20 m.y. and using the universal legend provided in class must
also be included with your report.

Although selection of seminar topics will occur early in the
course, it is strongly advised that research into your topic
begin as soon as possible. The purpose of this part of the
assessment is not only for you to become very familiar with the
Precambrian geological record but to also give you valuable
practice in scientific writing and presentation and being able to
critically assess what is really known about a particular
Precambrian province.
Precambrian Geology Compilation

 + + +
  + +         Granite
              TTG Suite
              Mafic Volcanics
  K           Ultramafic Volcanics (K=Komatiite)
 v v v
  v v         Felsic Volcanics
              Diabase Dyke Swarm
         Di   Clastic Sediments (Denote diamictite with “ Di”)
              Time of high grade metamorphism
              (A=amphibolite; G=granulite)
              BIF = Banded Iron Formation
              Ecl = Eclogite
              B = U-Pb baddeleyite age
              M = U-Pb monazite age
              Z = U-Pb zircon age
              T = U-Pb titanite age
              R = U-Pb rutile age
              DZ = Detrital zircon age
              XZ = Xenocrystic zircon age
              TND = Model Nd age

Time Line Scale: 1cm = 20 m.y.

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