Transcript Metamorphic Rock

Monolith
• Pena de Bernal (Bernal
Boulder) is the secondlargest monolith in the
world, after after Mount
Augustus in Western
Australia and the forth
tallest after Mt. Augustus,
the Rock of Gibraltar, and
Sugarloaf Mountain in Rio
de Janeiro. It is located
beside the small colonial
town of Villa de Bernal, in
the center of the Mexican
state of Queretaro. The
monumental rock arises
248 meters over the town.
Monolith
• Geological feature
such as a mountain,
that is a SINGLE
stone or rock
Metamorphic Rock
•
Metamorphism refers to changes in mineral composition or rock geometry
that occurs in SOLID rocks with increasing temperature and pressure
• HIGH temperatures and/or pressures are responsible for changing one
rock to another
• Metamorphism occurs below the Earth’s surface.
Metamorphic Rock
• Everywhere on Earth,
temperature and
pressure increases
with depth
• The ORIGINAL rock
from which a
metamorphic rock is
formed is called a
PROTOLITH
Metamorphic Rock
• http://www.classzone.com/books/earth_science/terc/conten
t/visualizations/es0607/es0607page01.cfm?chapter_no=vis
ualization
• http://www.wwnorton.com/college/geo/animations/foliatio
n.htm
• Foliation: the tendency for a metamorphic rock to split
along parallel planes (looks like layers)
Metamorphic Rock
•
Metamorphic Rocks are classified by TEXTURE and STRUCTURE
• Texture is used for rock geometry on the scale of grains; size of
grains, mutual geometrical arrangement of grains are aspects of
texture.
• Structure is used for rock geometry on a scale much larger than
grains; layering is an example of rock structure.
• Metamorphism alters both texture and structure of rocks
Fault / Faulting
Most kinds of metamorphic rocks,
change in mineral composition
is accompanied by strong
shearing deformation.
Deformation can change the shape
of grains in a rock
Faulting - brittle behavior in which
a rock responds to stress by
developing one or more
fractures. Deformation of the
rock concentrates along the
fractures. Slip along faults
frequently occurs through
sudden ruptures
Fault / Faulting
Regional Metamorphism
• Metamorphism that affects
enormous (large amounts)
volumes of rock in large
regions of the Earth’s crust
by an increase in
temperature and pressure
during deep burial is
called Regional
Metamorphism
• Subduction zones are the
most important setting for
regional metamorphism.
Contact Metamorphism
• Rocks in the immediate
vicinity of a newly
emplaced intrusive body
of magma are heated as
the magma loses heat to
its surroundings. If the
temperature becomes
sufficiently high, new
minerals that are stable at
high temperatures can
grow at the expense of the
preexisting minerals. This
is called Contact
Metamorphism
Metamorphic Rock
• The state rock of Colorado is Yule Marble.
• There is a town called Marble, Colorado. It is
located 4 hours Southwest of Denver, CO.