Geology Reference
In-Depth Information
TABLE 8.2 Some Representative Descriptions of Members and Formations of Systems in Ohio
Description
Formation or Member
System
Green plastic shale; sandstone
Fulton
Pennsylvanian
Coal
Meigs Creek No.
9
Pennsylvanian
Sandstone
Pomeroy
Pennsylvanian
Red plastic clay, clay shale
Pittsburgh
Pennsylvanian
Limestone
Cambridge
Pennsylvanian
Plastic clay and shaly sandstone
Sciotoville
Pennsylvanian
Conglomerate and shaly sandstone
Black Hand
Mississippian
Shale
Sunbury
Mississippian
Limestone
Berea
Mississippian
Shale
Ohio
Devonian
Limestone
Columbus
Devonian
Dolomite
Greenfield
Silurian
Dolomite
Guelph
Silurian
Limestone
Brassfield
Silurian
Limestone and calcareous shale
Richmond
Ordovician
Limestone and calcareous shale
Maysville
Ordovician
c.
Which formations or members would most likely
deform by flow? (Hint: Engineers in Ohio refer to them as
"those d
d redbeds"; Delong 1996.)
d. Much of the Appalachian Plateau (Physiographic
Province) is underlain by Pennsylvanian age and similar
rocks. Would you expect similar landslide conditions in
other area of the plateau such as Pittsburgh, Pennsylva-
nia, to the east of Athens County? Explain.
2. Knowing that the bedrock in Ohio is nearly flat, list those
slope stability factors (select from those in the Introduction
to Exercise 8) that are important in causing landslides in
Ohio.
FIGURE 8.17
Geologic map, of Ohio. Athens marked by dot.
Geologic systems marked by letters, Pa-Pennsylvanian,
Pm=Permian.
3. List two human activities that could increase the potential
for landslides.
QUESTIONS (8, PART C)
4. Figure 8.18 shows an apartment complex under construc-
tion near the top of a hill that has been graded to produce a
flat area for the buildings. On this aerial photo taken in 1968
near Athens, Ohio, identify
a.
a pond on the floodplain (P)
b. the apartment buildings with dark roofs at the con-
struction site (A) (one is given)
c.
two landslides (L)
1.
Locate Athens, Ohio, on Figure 8.17 the geologic map of
Ohio.
a.
What is the geologic system (age) of rocks in Athens?
b. From your knowledge of geologic materials (clays,
shales, limestones, sandstones, etc., which are reviewed
in Exercise 1) and the detailed descriptions in Table 8.2,
which of the four youngest geologic systems would be
the most susceptible to landsliding? Explain.
5. How many buildings are roofed or partially roofed?
