account for the resistance to bending of the strata
over the laccolith? How did the temperature vary
as the hot magma invaded the cold sedimentary
strata? We develop other models in later chapters
to address some of these questions.
Because the bottom contacts of the larger
igneous intrusions are not exposed, other conceptual models for the development of the structural domes could be viable. Based on geological
mapping of the Henry Mountain range and surrounding plateau country, Hunt (1953) proposed
that each of the major mountain peaks is underlain by a cylindrical stock of igneous rock that
extends well below the bottom contacts that were
inferred by Gilbert. This hypothesis has been challenged, based on more recent geological mapping
in the southern Henry Mountains and cross sections that were constructed from new structural
data (Jackson and Pollard, 1988). The two hypotheses for the shape of the magma chamber, stock or
laccolith, were debated in the literature and a
variety of geological and geophysical evidence
brought to bear on the subject (Hunt, 1988b).
1.6 Concluding remarks
One of our objectives for this chapter was to introduce a strategy for comprehending complex tectonic processes and their products over relevant
length and time scales by combining observational
data with both conceptual and mechanical
models. For each of the examples given we
described the phenomenon and then offered a
simple conceptual model that illustrates the key
elements of the physical process. Then we
described a mechanical model used to understand
the physical process. A second objective for this
chapter was to illustrate reductionism, a scientific
methodology in which complex processes are
broken up into their (relative few) fundamental
elements in order to understand each element in
isolation. Then, the elements are put back together
to understand how the whole system operates. This
methodology is espoused throughout the book.
Some of the topics in the introduction satisfy
our objective of demonstrating the possible roles
a structural geologist can take in society. For
example, career opportunities may be available
undertaking geological hazard assessment with
the US Geological Survey (USGS), being a member
of a production analysis team for an international
oil company, or participating in planetary exploration with the National Aeronautics and Space
Administration (NASA). We hope that these examples motivate students to learn more about the
fundamentals of structural geology by reading
this textbook.
24
MOTIVATIONS AND OPPORTUNITIES
over the laccolith? How did the temperature vary
as the hot magma invaded the cold sedimentary
strata? We develop other models in later chapters
to address some of these questions.
Because the bottom contacts of the larger
igneous intrusions are not exposed, other conceptual models for the development of the structural domes could be viable. Based on geological
mapping of the Henry Mountain range and surrounding plateau country, Hunt (1953) proposed
that each of the major mountain peaks is underlain by a cylindrical stock of igneous rock that
extends well below the bottom contacts that were
inferred by Gilbert. This hypothesis has been challenged, based on more recent geological mapping
in the southern Henry Mountains and cross sections that were constructed from new structural
data (Jackson and Pollard, 1988). The two hypotheses for the shape of the magma chamber, stock or
laccolith, were debated in the literature and a
variety of geological and geophysical evidence
brought to bear on the subject (Hunt, 1988b).
1.6 Concluding remarks
One of our objectives for this chapter was to introduce a strategy for comprehending complex tectonic processes and their products over relevant
length and time scales by combining observational
data with both conceptual and mechanical
models. For each of the examples given we
described the phenomenon and then offered a
simple conceptual model that illustrates the key
elements of the physical process. Then we
described a mechanical model used to understand
the physical process. A second objective for this
chapter was to illustrate reductionism, a scientific
methodology in which complex processes are
broken up into their (relative few) fundamental
elements in order to understand each element in
isolation. Then, the elements are put back together
to understand how the whole system operates. This
methodology is espoused throughout the book.
Some of the topics in the introduction satisfy
our objective of demonstrating the possible roles
a structural geologist can take in society. For
example, career opportunities may be available
undertaking geological hazard assessment with
the US Geological Survey (USGS), being a member
of a production analysis team for an international
oil company, or participating in planetary exploration with the National Aeronautics and Space
Administration (NASA). We hope that these examples motivate students to learn more about the
fundamentals of structural geology by reading
this textbook.
24
MOTIVATIONS AND OPPORTUNITIES