EARTH SYSTEM I:
GEOLOGICAL ENVIRONMENT

Lecture I. Introduction

A) Course Syllabus	B) Grading Criteria
C) Course Objectives	D) Nature of Geology
E) Geological Principles	F) Geological Scales of Time & Space
G) Geology and the Scientific Method	H) Geological Studies

• A) Course Syllabus

• B) Grading Criteria

• C) Course Objectives

• D) Nature of Geology
  • Historical & Physical

• E) Geological Principles

  -- Uniformitarianism:
  
  

  What's happening today happened in the past and will continue into the future.
  
  

  -- Original Horizontality:
  
  

  Earth is layered.
  
  
  
  Figure 1.1 Badlands National Monument, South Dakota.
  
  
  

  -- Superposition:
  
  

  A (youngest)
  B
  C (oldest)
  

F) Geological Scales of Time & Space

• TIME
  1. Relative Time ==> interpreted from geologic events
     
     
     
     Figure 1.2 Precambrian rocks - 2 ages of basalt dikes in gneiss (below dam of Lake Arbutus, Hatfield, WI).
     
     
     
  2. Absolute Time
     • a) Time Present (Real Time)
       • 0.001 sec (10*E-03 sec = microsec) -- seismic

       • < 1 ~ 100 years -- engineering

     • b) Time Past (Rock Clocks)
       • 1,000 years (10³ yr) -- glacial events

       • 1,000,000 years (10*E+06 yr = Ma) -- geodynamics

       • 1,000,000,000 years (10*E+09 yr = Ba) -- basement

     • c) Time Future
       • ca. 5 billion years or more

• SPACE
  • a) micro ==> Ångströms (Å = 10*E-09 m), millimeters (mm = 10*E-06 m), microns (µ = 10*E-03 m), etc.
    
    
    
    Figure 1.3 Thin section of fine grained igneous rock under a microscope (plagioclase, pyroxene, etc.).
    
    
    
  • b) small ==> feet (ft), meters (m), etc. to kilometers (km)
    
    
    
    Figure 1.4 Road cave-in along I-75, south of Jellico, TN, near top of Pine Mountain.
    
    
    
  • c) large, regional ==> tens to thousands (10³) of km
    
    
    
    Figure 1.5 Mississippi delta - a record of erosion (satellite view).
    
    
    
  • d) global
    
    
    
    Figure 1.6 Earth viewed from space (by our 1996 Bownocker Lecturer, Harrison "Jack" Schmitt [Geologist, Appolo 17 Astronaut, US Senator, Author, & CEO]).
    
    
    

G) Geology and the Scientific Method

1. Observe ==> collect data

2. Guess ==> make hypothesis about data patterns (i.e., variations)

3. Experiment ==> test for repeatability of a data patterns

4. Accept / Reject Hypothesis ==> make deduction

H) Geological Studies



Figure 1.7 Geology and its relationships with the other sciences (from Geology - An Introduction (2nd ed.), by Bates, Sweet, & Utgard, D. C. Heath and Co., 1973).