The Monteregian Hills (french: Collines Montérégiennes) is a linear chain of isolated hills in
Montreal
Montreal ( ; officially Montréal, ) is the second-most populous city in Canada and most populous city in the Canadian province of Quebec. Founded in 1642 as '' Ville-Marie'', or "City of Mary", it is named after Mount Royal, the triple ...
and
Montérégie
Montérégie () is an administrative region in the southwest part of Quebec. It includes the cities of Boucherville, Brossard, Châteauguay, Longueuil, Saint-Hyacinthe, Saint-Jean-sur-Richelieu, Salaberry-de-Valleyfield and Vaudreuil-Dorion.
...
, between the
Laurentians and the
Appalachians
The Appalachian Mountains, often called the Appalachians, (french: Appalaches), are a system of mountains in eastern to northeastern North America. The Appalachians first formed roughly 480 million years ago during the Ordovician Period. They ...
.
Etymology
The first definition of the Monteregian Hills came about in 1903 when Montreal geologist
Frank Dawson Adams
Frank Dawson Adams (September 17, 1859 – December 26, 1942) was a Canadian geologist.
Early life and education
Frank Dawson Adams was born into a prosperous, middle-class family in Montreal, Quebec.
Adams attended the High School of Montr ...
began referring to
Mount Royal
Mount Royal (french: link=no, Mont Royal, ) is a large intrusive rock hill or small mountain in the city of Montreal, immediately west of Downtown Montreal, Quebec, Canada. The best-known hypothesis for the origin of the name Montreal is the ...
(
Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
, ''Mons Regius'') and hills of similar geology in the
Saint Lawrence Lowlands
In religious belief, a saint is a person who is recognized as having an exceptional degree of holiness, likeness, or closeness to God. However, the use of the term ''saint'' depends on the context and denomination. In Catholic, Eastern Ortho ...
as the "Royal Mountains" (french: montagnes royales). Other hills in the chain included
Mont Saint-Bruno
Mont Saint-Bruno is part of the Monteregian Hills in southern Quebec, Canada. Its summit stands high and lies east of downtown Montreal.
This mountain has a ski resort, a natural area, and an apple orchard. Forests of beech, maple, oak, hicko ...
,
Mont Saint-Hilaire
Mont Saint-Hilaire (English: Mount Saint-Hilaire; abe, Wigwômadenizibo; see for other names) is an isolated hill, high, in the Montérégie region of southern Quebec. It is about thirty kilometres east of Montreal, and immediately east of the ...
,
Mont Saint-Grégoire,
Mont Rougemont,
Mont Yamaska,
Mont Shefford, and
Mont Brome.
It was only later that
Mont Mégantic, the Oka Hills, as well as the Saint-André and d'Iberville formations, were added to the list.
Geology
Each hill in the chain consists of an erosional remnant of
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...
intrusive igneous
Igneous rock (derived from the Latin word ''ignis'' meaning fire), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rock is formed through the cooling and solidification of magma or ...
rock and associated
hornfels
Hornfels is the group name for a set of contact metamorphic rocks that have been baked and hardened by the heat of intrusive igneous masses and have been rendered massive, hard, splintery, and in some cases exceedingly tough and durable. These pro ...
, which are more resistant to
weathering
Weathering is the deterioration of rocks, soils and minerals as well as wood and artificial materials through contact with water, atmospheric gases, and biological organisms. Weathering occurs ''in situ'' (on site, with little or no movement) ...
than the surrounding
sedimentary
Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles ...
rock. All of the hills have dark-coloured
mafic
A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks incl ...
rock such as
gabbro
Gabbro () is a phaneritic (coarse-grained), mafic intrusive igneous rock formed from the slow cooling of magnesium-rich and iron-rich magma into a holocrystalline mass deep beneath the Earth's surface. Slow-cooling, coarse-grained gabbro is ch ...
and
essexite; some also have large areas of
pulaskite,
syenite, and other light-coloured rock.
The Monteregian Hills are part of the
Great Meteor hotspot track, formed as a result of the
North American Plate
The North American Plate is a tectonic plate covering most of North America, Cuba, the Bahamas, extreme northeastern Asia, and parts of Iceland and the Azores. With an area of , it is the Earth's second largest tectonic plate, behind the Pacif ...
sliding westward over the long-lived
New England hotspot
The New England hotspot, also referred to as the Great Meteor hotspot and sometimes the Monteregian hotspot, is a volcanic hotspot in the North Atlantic Ocean. It created the Monteregian Hills intrusions in Montreal and Montérégie, the Whit ...
, and are the
eroded
Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is disti ...
remnants of intrusive
stocks. These intrusive stocks have been variously interpreted as the feeder intrusions of long
extinct volcano
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
On Earth, volcanoes are most often found where tectonic plates a ...
es, which would have been active about 125 million years ago,
[A Hundred-Million Year History of the Corner Rise and New England Seamounts http://www.oceanexplorer.noaa.gov/explorations/05stepstones/background/geologic_history/geologic_history.html Retrieved on 2007-08-01] or as intrusives that never breached the surface in volcanic activity. The lack of an obvious track west of the Monteregian Hills may be due either to failure of the plume to penetrate the
Canadian Shield, to the lack of recognizable intrusions, or to strengthening of the plume when it approached the Monteregian Hills region. However, there is evidence the hotspot track extends northwestwards, including
epeirogenic uplift,
mantle velocity anomalies and
kimberlitic volcanic features (e.g. the
Attawapiskat,
Kirkland Lake and
Lake Timiskaming
Lake Timiskaming or Lake Temiskaming (french: Lac Témiscamingue) is a large freshwater lake on the provincial boundary between Ontario and Quebec, Canada. The lake, which forms part of the Ottawa River, is in length and covers an area of ...
kimberlite fields) that become older away from the Monteregian Hills.
The shallow, rocky sandy loam soils of the summits are mostly covered in
forest
A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...
. Where the underlying rock is rich in
olivine
The mineral olivine () is a magnesium iron silicate with the chemical formula . It is a type of nesosilicate or orthosilicate. The primary component of the Earth's upper mantle, it is a common mineral in Earth's subsurface, but weathers quickl ...
, as over large areas of Mont Saint-Bruno and Mont Rougemont, these soils are classed as
dystric brunisol.
Podzol
In soil science, podzols are the typical soils of coniferous or boreal forests and also the typical soils of eucalypt forests and heathlands in southern Australia. In Western Europe, podzols develop on heathland, which is often a construct of ...
tends to develop over rock which lacks olivine, although many of these podzols lack an eluvial (Ae) horizon. Lower slopes are covered with aprons of gravel or sand. The sandy soils are usually podzols with classic Ae development; they often have subsoil hardpan and are undesirable for agriculture. The free-draining gravels are preferred for
apple
An apple is an edible fruit produced by an apple tree (''Malus domestica''). Apple trees are cultivated worldwide and are the most widely grown species in the genus ''Malus''. The tree originated in Central Asia, where its wild ancestor, ' ...
orchards, which grow in thermal belts where cold air can drain to the valley floor.
[https://sis.agr.gc.ca/cansis/publications/surveys/pq/pq62/pq62_report.pdf Orchard Soils of the Province of Quebec]
Gallery
Monteregian Hills in the Fall.jpg, Four of the Monteregian Hills in the late fall
Mont Saint-Hilaire south.jpg, Mont Saint-Hilaire
Mont Saint-Hilaire (English: Mount Saint-Hilaire; abe, Wigwômadenizibo; see for other names) is an isolated hill, high, in the Montérégie region of southern Quebec. It is about thirty kilometres east of Montreal, and immediately east of the ...
from the south
MT YAMASKA.jpg, aerial view of Mont Yamaska
Panorama Mont Rougemont.jpg, Mont Rougemont as seen from Mt. Saint-Grégoire
Mont Mégantic.jpg, Mont Mégantic as seen from the Stoke Mountains
See also
*
Volcanism of Canada
Volcanism, Volcanic activity is a major part of the geology of Canada and is characterized by many types of volcanic landform, including lava flows, volcanic plateaus, lava domes, cinder cones, stratovolcanoes, shield volcanoes, submarine volcano ...
*
Volcanism of Eastern Canada
External links
*
Les collines montérégiennesGeologic information about the chain
References
{{Mountains of Quebec
Mountain ranges of Quebec
Mountains of Quebec
Cretaceous volcanism
Igneous petrology of Quebec
Landforms of Montérégie