Geological processes that underlie the formation of mountains
Thrust
and reverse
fault
movement are an important component of mountain formation.
Illustration of mountains that developed on a
fold
that thrusted.
Mountain formation
refers to the geological processes that underlie the formation of
mountains
. These processes are associated with large-scale movements of the
Earth's crust
(
tectonic plates
).
[1]
Folding
,
faulting
,
volcanic activity
,
igneous intrusion
and
metamorphism
can all be parts of the
orogenic process
of mountain building.
[2]
The formation of mountains is not necessarily related to the
geological structures
found on it.
[3]
From the late 18th century until its replacement by
plate tectonics
in the 1960s,
geosyncline theory
was used to explain much mountain-building.
[4]
The understanding of specific landscape features in terms of the underlying
tectonic
processes is called
tectonic geomorphology
, and the study of geologically young or ongoing processes is called
neotectonics
.
[5]
[
clarification needed
]
Types of mountains
[
edit
]
There are five main types of mountains:
volcanic
,
fold
,
plateau
,
fault-block
, and
dome
. A more detailed classification useful on a local scale predates
plate tectonics
and adds to these categories.
[6]
Volcanic mountains
[
edit
]
Annotated view includes
Ushkovsky
,
Tolbachik
,
Bezymianny
,
Zimina
, and
Udina
stratovolcanoes
of
Kamchatka
, Russia. Oblique view taken on November 12, 2013, from ISS.
[7]
Stratovolcanoes associated with a
subduction
zone (left) and a
spreading ridge
volcano (right). A
hotspot
volcano is center.
[8]
Movements of tectonic plates create
volcanoes
along the plate boundaries, which erupt and form mountains. A
volcanic arc system
is a series of volcanoes that form near a
subduction
zone where the crust of a sinking
oceanic plate
melts and drags water down with the subducting crust.
[9]
The Dome of
Vitosha
mountain next to
Sofia
Most volcanoes occur in a band encircling the Pacific Ocean (the
Pacific Ring of Fire
), and in another that extends from the Mediterranean across Asia to join the Pacific band in the Indonesian Archipelago. The most important types of volcanic mountain are
composite cones
or
stratovolcanoes
and
shield volcanoes
.
[10]
[11]
A shield volcano has a gently sloping cone because of the low viscosity of the emitted material, primarily
basalt
.
Mauna Loa
is the classic example, with a slope of 4°-6°. (The relation between slope and viscosity falls under the topic of
angle of repose
.
[12]
) A composite volcano or stratovolcano has a more steeply rising cone (33°-40°),
[13]
because of the higher viscosity of the emitted material, and
eruptions
are more violent and less frequent than for shield volcanoes. Examples include
Vesuvius
,
Kilimanjaro
,
Mount Fuji
,
Mount Shasta
,
Mount Hood
and
Mount Rainier
.
[14]
Fold mountains
[
edit
]
Zard-Kuh
, a fold mountain in the central
Zagros
range of Iran.
When
plates collide
or undergo
subduction
(that is, ride one over another), the plates tend to buckle and
fold
, forming mountains. Most of the major continental mountain ranges are associated with thrusting and folding or
orogenesis
. Examples are the
Balkan Mountains
, the
Jura
and the
Zagros
mountains.
[15]
Block mountains
[
edit
]
Fault-block mountain of the tilted type.
[16]
Sierra Nevada Mountains (formed by delamination) as seen from the
International Space Station
.
When a
fault block
is raised or tilted, a block mountain can result.
[17]
Higher blocks are called
horsts
,
and troughs are called
grabens
. A spreading apart of the surface causes tensional forces. When the tensional forces are strong enough to cause a plate to split apart, it does so such that a center block drops down relative to its flanking blocks.
An example is the
Sierra Nevada
range, where
delamination
created a block 650 km long and 80 km wide that consists of many individual portions tipped gently west, with east facing slips rising abruptly to produce the highest mountain front in the continental United States.
[18]
[19]
Another example is the
Rila
?
Rhodope
massif
in
Bulgaria
, including the well defined horsts of
Belasitsa
(linear horst), Rila mountain (vaulted domed shaped horst) and
Pirin mountain
?a horst forming a massive
anticline
situated between the complex graben valleys of the
Struma
and
Mesta
rivers.
[20]
[21]
[22]
Uplifted passive margins
[
edit
]
Unlike orogenic mountains there is no widely accepted
geophysical
model that explains elevated passive
continental margins
such as the
Scandinavian Mountains
, eastern
Greenland
, the
Brazilian Highlands
, or Australia's
Great Dividing Range
.
[23]
[24]
Different elevated passive continental margins most likely share the same mechanism of uplift. This mechanism is possibly related to far-field stresses in Earth's
lithosphere
. According to this view elevated passive margins can be likened to giant
anticlinal
lithospheric folds, where folding is caused by horizontal compression acting on a thin to thick crust transition zone (as are all passive margins).
[25]
[26]
Models
[
edit
]
Hotspot volcanoes
[
edit
]
Hotspots
are supplied by a
magma
source in the
Earth's mantle
called a
mantle plume
. Although originally attributed to a melting of subducted oceanic crust, recent evidence belies this connection.
[27]
The mechanism for plume formation remains a research topic.
Fault blocks
[
edit
]
Several movements of the Earth's crust that lead to mountains are associated with
faults
. These movements actually are amenable to analysis that can predict, for example, the height of a raised block and the width of an intervening rift between blocks using the
rheology
of the layers and the forces of
isostasy
. Early bent plate models predicting fractures and fault movements have evolved into today's kinematic and flexural models.
[28]
[29]
See also
[
edit
]
References
[
edit
]
- ^
Steven M. Stanley (2004).
"Mountain building"
.
Earth system history
(2nd ed.). Macmillan. p. 207.
ISBN
978-0-7167-3907-4
.
- ^
Robert J. Twiss
;
Eldridge M. Moores
(1992).
"Plate tectonic models of orogenic core zones"
.
Structural Geology
(2nd ed.). Macmillan. p.
493
.
ISBN
978-0-7167-2252-6
.
- ^
Ollier, Cliff
; Pain, Colin (2000).
The Origin of Mountains
. Routledge. p.
1
.
ISBN
978-0-415-19890-5
.
- ^
"Geosynclinal Theory"
.
publish.illinois.edu
. University of Illinois at Urbana-Champaign
. Retrieved
March 8,
2018
.
The major mountain-building idea that was supported from the 19th century and into the 20th is the geosynclinal theory.
- ^
Kurt Stuwe (2007).
"§4.5 Geomorphology"
.
Geodynamics of the lithosphere: an introduction
(2nd ed.). Springer. p. 178.
ISBN
978-3-540-71236-7
.
- ^
Andrew Goudie (2004).
Encyclopedia of geomorphology; Volume 2
. Routledge. p. 701.
ISBN
978-0-415-32738-1
.
- ^
NASA - Activity at Kliuchevskoi
- ^
Victor Schmidt; William Harbert (2003).
Planet Earth and the New Geoscience
(4th ed.). Kendall Hunt. pp. 46?47.
ISBN
978-0-7872-9355-0
.
- ^
Stephen D Butz (2004).
"Chapter 8: Plate tectonics"
.
Science of Earth Systems
. Thompson/Delmar Learning. p.
136
.
ISBN
978-0-7668-3391-3
.
- ^
John Gerrard (1990).
"Types of volcano"
.
Mountain environments: an examination of the physical geography of mountains
. MIT Press. p.
194
.
ISBN
978-0-262-07128-4
.
- ^
Robert Wayne Decker; Barbara Decker (2005).
"Chapter 8: Hot spots"
.
Volcanoes
(4th ed.). Macmillan. p. 113
ff
.
ISBN
978-0-7167-8929-1
.
- ^
Arthur Holmes
;
Donald Duff
(2004).
Holmes Principles of Physical Geology
(4th ed.). Taylor & Francis. p. 209.
ISBN
978-0-7487-4381-0
.
- ^
Transactions of the American Society of Civil Engineers, Volume 39
. American Society of Civil Engineers. 1898. p. 62.
- ^
James Shipman; Jerry D. Wilson; Aaron Todd (2007).
"Minerals, rocks and volcanoes"
.
An Introduction to Physical Science
(12th ed.). Cengage Learning. p. 650.
ISBN
978-0-618-93596-3
.
- ^
Michael P Searle
(2007).
"Diagnostic features and processes in the construction and evolution of Oman-, Zagros-, Himalayan-, Karakoram-, and Tibetan type orogenic belts"
. In
Robert D Hatcher Jr.
; MP Carlson; JH McBride & JR Martinez Catalan (eds.).
4-D framework of continental crust
. Geological Society of America. p. 41
ff
.
ISBN
978-0-8137-1200-0
.
- ^
Chris C. Park (2001).
"Figure 6.11"
.
The environment: principles and applications
(2nd ed.). Routledge. p. 160.
ISBN
9780415217705
.
- ^
Scott Ryan (2006).
"Figure 13-1"
.
CliffsQuickReview Earth Science
. Wiley.
ISBN
978-0-471-78937-6
.
- ^
John Gerrard (1990-04-12).
Reference cited
. p. 9.
ISBN
978-0-262-07128-4
.
- ^
Lee, C.-T.; Yin, Q; Rudnick, RL; Chesley, JT; Jacobsen, SB (2000).
"Osmium Isotopic Evidence for Mesozoic Removal of Lithospheric Mantle Beneath the Sierra Nevada, California"
(PDF)
.
Science
.
289
(5486): 1912?6.
Bibcode
:
2000Sci...289.1912L
.
doi
:
10.1126/science.289.5486.1912
.
PMID
10988067
. Archived from
the original
(PDF)
on 2011-06-15.
- ^
Мичев (Michev), Николай (Nikolay); Михайлов (Mihaylov), Цветко (Tsvetko); Вапцаров (Vaptsarov), Иван (Ivan); Кираджиев (Kiradzhiev), Светлин (Svetlin) (1980).
Географски речник на България
[
Geographic Dictionary of Bulgaria
] (in Bulgarian). Sofia: Наука и култура (Nauka i kultura). p. 368.
- ^
Димитрова (Dimitrova), Людмила (Lyudmila) (2004).
Национален парк "Пирин". План за управление
[
Pirin National Park. Management Plan
] (in Bulgarian). и колектив. Sofia:
Ministry of Environment and Water
, Bulgarian Foundation "Biodiversity". p. 53.
- ^
Дончев (Donchev), Дончо (Doncho); Каракашев (Karakashev), Христо (Hristo) (2004).
Теми по физическа и социално-икономическа география на България
[
Topics on Physical and Social-Economic Geography of Bulgaria
] (in Bulgarian). Sofia: Ciela. pp. 128?129.
ISBN
954-649-717-7
.
- ^
Bonow, Johan M. (2009).
"atlantens kustberg och hogslatter ? gamla eller unga?"
(PDF)
.
www.geografitorget.se
(in Swedish). Geografilararnas Riksforening.
- ^
Green, Paul F.;
Lidmar-Bergstrom, Karna
; Japsen, Peter; Bonow, Johan M.; Chalmers, James A. (2013).
"Stratigraphic landscape analysis, thermochronology and the episodic development of elevated, passive continental margins"
.
Geological Survey of Denmark and Greenland Bulletin
.
30
: 18.
doi
:
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.
- ^
Japsen, Peter; Chalmers, James A.; Green, Paul F.; Bonow, Johan M. (2012). "Elevated, passive continental margins: Not rift shoulders, but expressions of episodic, post-rift burial and exhumation".
Global and Planetary Change
. 90?91: 73?86.
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:
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.
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:
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.
- ^
Løseth and Hendriksen 2005
- ^
Y Niu & MJ O'Hara (2004).
"Chapter 7: Mantle plumes are NOT from ancient oceanic crust"
. In Roger Hekinian; Peter Stoffers & Jean-Louis Cheminee (eds.).
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. Springer. p. 239
ff
.
ISBN
978-3-540-40859-8
.
- ^
AB Watts (2001).
"§7.2 Extensional tectonics and rifting"
.
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. Cambridge University Press. p. 295.
ISBN
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.
- ^
GD Karner & NW Driscoll (1999).
"Style, timing and distribution of tectonic deformation across the Exmouth Plateau, northwest Australia, determined from stratal architecture and quantitative basin modelling"
. In Conall Mac Niocaill & Paul Desmond Ryan (eds.).
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. Geological society. p. 280.
ISBN
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.
External links
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]
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