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90-631: The Matapedia Valley (French: vallée de la Matapédia ) was formed by the Chic-Choc Mountains of eastern Québec . Its name is derived from the river that traverses the valley, as well as the lake that lies in its center. It is situated in the southwest of the Gaspé Peninsula and stretches 375 km (233 mi). The land is primarily made up of forest and agriculture, and is home to more than 20,000 inhabitants in some thirty municipalities. Most of them are concentrated along

180-455: A Mohs hardness of 2 to 4, dense limestone can have a crushing strength of up to 180 MPa . For comparison, concrete typically has a crushing strength of about 40 MPa. Although limestones show little variability in mineral composition, they show great diversity in texture. However, most limestone consists of sand-sized grains in a carbonate mud matrix. Because limestones are often of biological origin and are usually composed of sediment that

270-463: A bloom of cyanobacteria or microalgae . However, stable isotope ratios in modern carbonate mud appear to be inconsistent with either of these mechanisms, and abrasion of carbonate grains in high-energy environments has been put forward as a third possibility. Formation of limestone has likely been dominated by biological processes throughout the Phanerozoic , the last 540 million years of

360-434: A carbonate rock outcrop can be estimated in the field by etching the surface with dilute hydrochloric acid. This etches away the calcite and aragonite, leaving behind any silica or dolomite grains. The latter can be identified by their rhombohedral shape. Crystals of calcite, quartz , dolomite or barite may line small cavities ( vugs ) in the rock. Vugs are a form of secondary porosity, formed in existing limestone by

450-588: A catalyst for demographic development in the valley. Indeed, between 1900 and 1940, the population of the valley rose to over thirty thousand inhabitants. In the west of the valley, along the Mitis River on the Matapedia Road, was the first parish to be canonically erected in 1868: Sainte-Angèle-de-Merici. Inhabited since 1870 and canonically erected in 1873, the Saint-Moïse parish is the oldest in

540-616: A central quartz grain or carbonate mineral fragment. These likely form by direct precipitation of calcium carbonate onto the ooid. Pisoliths are similar to ooids, but they are larger than 2 mm in diameter and tend to be more irregular in shape. Limestone composed mostly of ooids is called an oolite or sometimes an oolitic limestone . Ooids form in high-energy environments, such as the Bahama platform, and oolites typically show crossbedding and other features associated with deposition in strong currents. Oncoliths resemble ooids but show

630-449: A change in environment that increases the solubility of calcite. Dense, massive limestone is sometimes described as "marble". For example, the famous Portoro "marble" of Italy is actually a dense black limestone. True marble is produced by recrystallization of limestone during regional metamorphism that accompanies the mountain building process ( orogeny ). It is distinguished from dense limestone by its coarse crystalline texture and

720-949: A composition reflecting the organisms that produced them and the environment in which they were produced. Low-magnesium calcite skeletal grains are typical of articulate brachiopods , planktonic (free-floating) foraminifera, and coccoliths . High-magnesium calcite skeletal grains are typical of benthic (bottom-dwelling) foraminifera, echinoderms , and coralline algae . Aragonite skeletal grains are typical of molluscs , calcareous green algae , stromatoporoids , corals , and tube worms . The skeletal grains also reflect specific geological periods and environments. For example, coral grains are more common in high-energy environments (characterized by strong currents and turbulence) while bryozoan grains are more common in low-energy environments (characterized by quiet water). Ooids (sometimes called ooliths) are sand-sized grains (less than 2mm in diameter) consisting of one or more layers of calcite or aragonite around

810-412: A considerable fraction of the limestone bed. At depths greater than 1 km (0.62 miles), burial cementation completes the lithification process. Burial cementation does not produce stylolites. When overlying beds are eroded, bringing limestone closer to the surface, the final stage of diagenesis takes place. This produces secondary porosity as some of the cement is dissolved by rainwater infiltrating

900-483: A drop of dilute hydrochloric acid is dropped on it. Dolomite is also soft but reacts only feebly with dilute hydrochloric acid, and it usually weathers to a characteristic dull yellow-brown color due to the presence of ferrous iron. This is released and oxidized as the dolomite weathers. Impurities (such as clay , sand, organic remains, iron oxide , and other materials) will cause limestones to exhibit different colors, especially with weathered surfaces. The makeup of

990-637: A few million years, as this is the most stable form of calcium carbonate. Ancient carbonate formations of the Precambrian and Paleozoic contain abundant dolomite, but limestone dominates the carbonate beds of the Mesozoic and Cenozoic . Modern dolomite is quite rare. There is evidence that, while the modern ocean favors precipitation of aragonite, the oceans of the Paleozoic and middle to late Cenozoic favored precipitation of calcite. This may indicate

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1080-455: A few thousand years. As rainwater mixes with groundwater, aragonite and high-magnesium calcite are converted to low-calcium calcite. Cementing of thick carbonate deposits by rainwater may commence even before the retreat of the sea, as rainwater can infiltrate over 100 km (60 miles) into sediments beneath the continental shelf. As carbonate sediments are increasingly deeply buried under younger sediments, chemical and mechanical compaction of

1170-435: A limestone sample except in thin section and are less common in ancient limestones, possibly because compaction of carbonate sediments disrupts them. Limeclasts are fragments of existing limestone or partially lithified carbonate sediments. Intraclasts are limeclasts that originate close to where they are deposited in limestone, while extraclasts come from outside the depositional area. Intraclasts include grapestone , which

1260-471: A lower Mg/Ca ratio in the ocean water of those times. This magnesium depletion may be a consequence of more rapid sea floor spreading , which removes magnesium from ocean water. The modern ocean and the ocean of the Mesozoic have been described as "aragonite seas". Most limestone was formed in shallow marine environments, such as continental shelves or platforms . Such environments form only about 5% of

1350-525: A lower diversity of organisms and a greater fraction of silica and clay minerals characteristic of marls . The Green River Formation is an example of a prominent freshwater sedimentary formation containing numerous limestone beds. Freshwater limestone is typically micritic. Fossils of charophyte (stonewort), a form of freshwater green algae, are characteristic of these environments, where the charophytes produce and trap carbonates. Limestones may also form in evaporite depositional environments . Calcite

1440-523: A mechanism for dolomitization, with one 2004 review paper describing it bluntly as "a myth". Ordinary seawater is capable of converting calcite to dolomite, if the seawater is regularly flushed through the rock, as by the ebb and flow of tides (tidal pumping). Once dolomitization begins, it proceeds rapidly, so that there is very little carbonate rock containing mixed calcite and dolomite. Carbonate rock tends to be either almost all calcite/aragonite or almost all dolomite. About 20% to 25% of sedimentary rock

1530-448: A plausible source of mud. Another possibility is direct precipitation from the water. A phenomenon known as whitings occurs in shallow waters, in which white streaks containing dispersed micrite appear on the surface of the water. It is uncertain whether this is freshly precipitated aragonite or simply material stirred up from the bottom, but there is some evidence that whitings are caused by biological precipitation of aragonite as part of

1620-449: A radial rather than layered internal structure, indicating that they were formed by algae in a normal marine environment. Peloids are structureless grains of microcrystalline carbonate likely produced by a variety of processes. Many are thought to be fecal pellets produced by marine organisms. Others may be produced by endolithic (boring) algae or other microorganisms or through breakdown of mollusc shells. They are difficult to see in

1710-499: Is Lac-au-Saumon, which is fed into and drained by the Matapedia River. The geographic territory of the valley comprises the regional county municipalities of La Mitis , La Matapédia and Avignon , which cover thirty municipalities. Important economic centers include Amqui , Causapscal and Sayabec . The valley is currently home to more than 20,000 inhabitants. Its population density is much higher along Lake Matapedia and

1800-560: Is also favored on the seaward margin of shelves and platforms, where there is upwelling deep ocean water rich in nutrients that increase organic productivity. Reefs are common here, but when lacking, ooid shoals are found instead. Finer sediments are deposited close to shore. The lack of deep sea limestones is due in part to rapid subduction of oceanic crust, but is more a result of dissolution of calcium carbonate at depth. The solubility of calcium carbonate increases with pressure and even more with higher concentrations of carbon dioxide, which

1890-399: Is an obsolete and poorly-defined term used variously for dolomite, for limestone containing significant dolomite ( dolomitic limestone ), or for any other limestone containing a significant percentage of magnesium . Most limestone was formed in shallow marine environments, such as continental shelves or platforms , though smaller amounts were formed in many other environments. Much dolomite

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1980-482: Is an uncommon mineral in limestone, and siderite or other carbonate minerals are rare. However, the calcite in limestone often contains a few percent of magnesium . Calcite in limestone is divided into low-magnesium and high-magnesium calcite, with the dividing line placed at a composition of 4% magnesium. High-magnesium calcite retains the calcite mineral structure, which is distinct from dolomite. Aragonite does not usually contain significant magnesium. Most limestone

2070-402: Is carbonate rock, and most of this is limestone. Limestone is found in sedimentary sequences as old as 2.7 billion years. However, the compositions of carbonate rocks show an uneven distribution in time in the geologic record. About 95% of modern carbonates are composed of high-magnesium calcite and aragonite. The aragonite needles in carbonate mud are converted to low-magnesium calcite within

2160-474: Is clusters of peloids cemented together by organic material or mineral cement. Extraclasts are uncommon, are usually accompanied by other clastic sediments, and indicate deposition in a tectonically active area or as part of a turbidity current . The grains of most limestones are embedded in a matrix of carbonate mud. This is typically the largest fraction of an ancient carbonate rock. Mud consisting of individual crystals less than 5 μm (0.20 mils) in length

2250-416: Is commonly white to gray in color. Limestone that is unusually rich in organic matter can be almost black in color, while traces of iron or manganese can give limestone an off-white to yellow to red color. The density of limestone depends on its porosity, which varies from 0.1% for the densest limestone to 40% for chalk. The density correspondingly ranges from 1.5 to 2.7 g/cm . Although relatively soft, with

2340-406: Is composed mostly of the minerals calcite and aragonite , which are different crystal forms of CaCO 3 . Limestone forms when these minerals precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for

2430-420: Is controlled largely by the amount of dissolved carbon dioxide ( CO 2 ) in the water. This is summarized in the reaction: Increases in temperature or decreases in pressure tend to reduce the amount of dissolved CO 2 and precipitate CaCO 3 . Reduction in salinity also reduces the solubility of CaCO 3 , by several orders of magnitude for fresh water versus seawater. Near-surface water of

2520-545: Is converted to low-magnesium calcite. Diagenesis is the likely origin of pisoliths , concentrically layered particles ranging from 1 to 10 mm (0.039 to 0.394 inches) in diameter found in some limestones. Pisoliths superficially resemble ooids but have no nucleus of foreign matter, fit together tightly, and show other signs that they formed after the original deposition of the sediments. Silicification occurs early in diagenesis, at low pH and temperature, and contributes to fossil preservation. Silicification takes place through

2610-503: Is deposited close to where it formed, classification of limestone is usually based on its grain type and mud content. Most grains in limestone are skeletal fragments of marine organisms such as coral or foraminifera . These organisms secrete structures made of aragonite or calcite, and leave these structures behind when they die. Other carbonate grains composing limestones are ooids , peloids , and limeclasts ( intraclasts and extraclasts  [ ca ] ). Skeletal grains have

2700-460: Is described as coquinite . Chalk is a soft, earthy, fine-textured limestone composed of the tests of planktonic microorganisms such as foraminifera, while marl is an earthy mixture of carbonates and silicate sediments. Limestone forms when calcite or aragonite precipitate out of water containing dissolved calcium, which can take place through both biological and nonbiological processes. The solubility of calcium carbonate ( CaCO 3 )

2790-617: Is described as micrite . In fresh carbonate mud, micrite is mostly small aragonite needles, which may precipitate directly from seawater, be secreted by algae, or be produced by abrasion of carbonate grains in a high-energy environment. This is converted to calcite within a few million years of deposition. Further recrystallization of micrite produces microspar , with grains from 5 to 15 μm (0.20 to 0.59 mils) in diameter. Limestone often contains larger crystals of calcite, ranging in size from 0.02 to 0.1 mm (0.79 to 3.94 mils), that are described as sparry calcite or sparite . Sparite

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2880-462: Is distinguished from micrite by a grain size of over 20 μm (0.79 mils) and because sparite stands out under a hand lens or in thin section as white or transparent crystals. Sparite is distinguished from carbonate grains by its lack of internal structure and its characteristic crystal shapes. Geologists are careful to distinguish between sparite deposited as cement and sparite formed by recrystallization of micrite or carbonate grains. Sparite cement

2970-470: Is located along this highway. Additionally, there are two provincial highways that snake through the valley which are perpendicular to the St. Lawrence River Hwy 297 , which goes from Saint-Moïse to Baie-des-Sables , and Hwy 195 , which runs from Amqui to Matane . A railroad that crosses the valley on the same axis as the 132 defines the eastern extremity of the valley, which allows access to New Brunswick and

3060-560: Is one of the first minerals to precipitate in marine evaporites. Most limestone is formed by the activities of living organisms near reefs, but the organisms responsible for reef formation have changed over geologic time. For example, stromatolites are mound-shaped structures in ancient limestones, interpreted as colonies of cyanobacteria that accumulated carbonate sediments, but stromatolites are rare in younger limestones. Organisms precipitate limestone both directly as part of their skeletons, and indirectly by removing carbon dioxide from

3150-473: Is otherwise chemically fairly pure, with clastic sediments (mainly fine-grained quartz and clay minerals ) making up less than 5% to 10% of the composition. Organic matter typically makes up around 0.2% of a limestone and rarely exceeds 1%. Limestone often contains variable amounts of silica in the form of chert or siliceous skeletal fragments (such as sponge spicules, diatoms , or radiolarians ). Fossils are also common in limestone. Limestone

3240-472: Is produced by decaying organic matter settling into the deep ocean that is not removed by photosynthesis in the dark depths. As a result, there is a fairly sharp transition from water saturated with calcium carbonate to water unsaturated with calcium carbonate, the lysocline , which occurs at the calcite compensation depth of 4,000 to 7,000 m (13,000 to 23,000 feet). Below this depth, foraminifera tests and other skeletal particles rapidly dissolve, and

3330-518: Is secondary dolomite, formed by chemical alteration of limestone. Limestone is exposed over large regions of the Earth's surface, and because limestone is slightly soluble in rainwater, these exposures often are eroded to become karst landscapes. Most cave systems are found in limestone bedrock. Limestone has numerous uses: as a chemical feedstock for the production of lime used for cement (an essential component of concrete ), as aggregate for

3420-576: The Acadians . Additionally, one can observe the Acadian flag in many municipalities in the area, notably Amqui, Causapscal, and Lac-au-Saumon. The Matapedia Valley is a touristic sub-region of Gaspésie. The valley is renowned for its outdoor activities, including skiing, hunting, and fishing. Salmon fishing is popular on Matapedia River, and Val-d'Irène offers 26 trails for snowboarders and downhill skiers in addition to many snowshoeing trails. For hikers,

3510-571: The Chic-Choc mountain range , which is situated at the northern extremity of the Appalachians. It has two main bodies of water: Lake Matapedia , which extends from Sayabec to Amqui, and Lac-au-Saumon , situated in a town by the same name . The valley reaches from the St. Lawrence River to Chaleur Bay . The northwest region of the valley is rather flat and surrounded by small mounts that do not exceed 400 metres (1,300 ft). More towards

3600-623: The Devonian and Silurian periods. The territory of the Matapedia Valley is drained through the Matapedia River , which has a watershed area of 3,824 square kilometres (1,476 sq mi). It is known for its Atlantic salmon fishing. Additionally, the valley has more than 200 lakes, the most significant of which is Lake Matapedia, with an area of 38 square kilometres (15 sq mi). The valley's second largest lake

3690-516: The Great Depression . The logging industry was the primary pull factor for settlers in the valley. The development of agriculture allowed for permanent colonies and the creation of Catholic parishes. Logging companies such as John Fenderson Lumber, Price Bros., and Brown Corporation built the industrial framework necessary for the growth of the valley's villages. Throughout its history, Matapedia Valley has shared much of its culture with

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3780-704: The International Appalachian Trail cuts through the valley. Additionally, the Seignory of Lac-Matapédia regional park provides many trails through the Chic-Chocs. Chic-Choc Mountains The name Chic-Chocs comes from the Mi'kmaq word sigsôg , meaning "crags" or "rocky mountains." It has undergone many different spellings over time, including Chikchâks (1836), Shick-shock (1857), and Chick-Saws (1863). The Chic-Chocs run parallel to

3870-408: The International Appalachian Trail , passes through these mountains. Quebec's Parc national de la Gaspésie protects most of the mountain range. This Quebec location article is a stub . You can help Misplaced Pages by expanding it . Limestone Limestone ( calcium carbonate CaCO 3 ) is a type of carbonate sedimentary rock which is the main source of the material lime . It

3960-545: The Restigouche River to the east, which borders New Brunswick. The village of Matapédia, Quebec lies on the valley's eastern tip. The valley is situated south of the Saint Lawrence River in the administrative regions of Bas-Saint-Laurent and Gaspésie–Îles-de-la-Madeleine . This makes it the only region in the Gaspé Peninsula that does not border the sea. The Matapedia Valley is dug into

4050-506: The St. Lawrence River and are located some 20 to 40 kilometers inland. They are a narrow band of mountains approximately 95 kilometres (59 mi) long and 10 kilometres (6.2 mi) wide. The Chic-Chocs are heavily eroded , with rounded, flattened tops and steep sides. Over 32 mountains in the range have peaks higher than 1,000 metres (3,300 ft); the highest is Mount Jacques-Cartier at 1,268 metres (4,160 ft). Caribou can be found in

4140-537: The 1880s, the valley had about 1,700 inhabitants and, at the dawn of the twentieth century, it had grown to 8,000. The state of Kempt Road remained deplorable until the outbreak of the American Civil War , which generated a big enough concern for the government to finally invest the sums necessary for the establishment of a road worthy of the name. The original route had been changed so that the path starts at Sainte-Flavie instead of Métis. Starting in 1860,

4230-670: The Amqui parish. Lac-au-Saumon was mainly developed by the Acadians. In 1910, it was the Sainte-Florence parish's turn to be canonically erected, and in just ten years, it had already attracted around 700 residents. One year later, the Saint-André-de-Restigouche parish sees its first resident parish priest. Finally, the parish of La Rédemption was created in 1936 as part of a government stimulation plan following

4320-806: The Assemetquaghan stream in present-day Routhierville. In addition to these guardians, Noble's son settled near his father in The Forks, known today as the Forks Park in Causapscal, and Ferdinand Duval who made his home in Lac-au-Saumon. During this time, Acadians from Prince Edward Island and the Magdalen Islands also started coming to the area and clearing land by settling in the Matapedia Valley, especially in its west. In

4410-496: The Earth's history. Limestone may have been deposited by microorganisms in the Precambrian , prior to 540 million years ago, but inorganic processes were probably more important and likely took place in an ocean more highly oversaturated in calcium carbonate than the modern ocean. Diagenesis is the process in which sediments are compacted and turned into solid rock . During diagenesis of carbonate sediments, significant chemical and textural changes take place. For example, aragonite

4500-638: The Gaspé peninsula. There are two trains that service the valley: the Ocean and the Montreal – Gaspé train , both of which are owned by Via Rail and are combined from Matapédia onwards. The Mi'kmaq and Maliseet lived in the territory of the Matapedia Valley before the arrival of Europeans in North America. They primarily lived around Chaleur Bay , but they traveled along the Matapedia River to fish at

4590-408: The Matapedia River than the more remote areas of the valley. Indeed, along the lake and river, the population density is 12 inhabitants per km while in the valley's uplands, it is 5.0/km (13/sq mi). The unincorporated territories of the valley are nearly uninhabited. The main axis of communication is Highway 132 which runs northwest to southeast. The majority of the population in this area

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4680-668: The Matapedia Road had begun replacing Kempt Road. Finally, in 1867, Matapedia Road was completed. At a Quebec conference in October 1864, the decision was made to join the Intercolonial Railway to the Grand Trunk at Rivière-du-Loup . In 1871, the construction of a railroad crossing the valley had begun, an undertaking that had been completed in 1876. Paired with the Matapedia and Kempt roads, this railway acted as

4770-551: The Matapedia Valley is a land conducive to becoming an agricultural center of importance. Shortly before this time, the War of 1812 demonstrated that Canada was vulnerable to attacks from the United States and the need to connect Upper and Lower Canada to the maritime colonies. Residents of Gaspesia had been demanding means of communication with the urban centre for some time, as outside of navigation season, they were cut off from

4860-410: The area Magabegeak which means "roughly flowing". It has also been spelled many different ways over time such as Matapediach , Madapeguia , Matapeguia , Matapediac, Matakpediack, Madapeguia, Metapedia , or Matapediac . At the western extremity of the valley is the village of Sainte-Angèle-de-Mérici, Quebec . From north to south, it runs a length of 375 km (233 mi) until it reaches

4950-434: The base of roads, as white pigment or filler in products such as toothpaste or paint, as a soil conditioner , and as a popular decorative addition to rock gardens . Limestone formations contain about 30% of the world's petroleum reservoirs . Limestone is composed mostly of the minerals calcite and aragonite , which are different crystal forms of calcium carbonate ( CaCO 3 ). Dolomite , CaMg(CO 3 ) 2 ,

5040-657: The beds. This may include the formation of vugs , which are crystal-lined cavities within the limestone. Diagenesis may include conversion of limestone to dolomite by magnesium-rich fluids. There is considerable evidence of replacement of limestone by dolomite, including sharp replacement boundaries that cut across bedding. The process of dolomitization remains an area of active research, but possible mechanisms include exposure to concentrated brines in hot environments ( evaporative reflux ) or exposure to diluted seawater in delta or estuary environments ( Dorag dolomitization ). However, Dorag dolomitization has fallen into disfavor as

5130-632: The center of the valley, near St. Cleophas and St. Irène , the peaks reach an altitude of 800 metres (2,600 ft), one of which is the Val-d'Irène ski resort (685 metres (2,247 ft)). The southeastern area of the valley is more rugged and steep, with summits reaching about 600 metres (2,000 ft). At the other extreme, Lake Matapedia rests at an altitude of 158 metres (518 ft). The Matapedia Valley includes 20,000 hectares (77 sq mi) of land dedicated to agriculture and 500,000 hectares (1,900 sq mi) of forest divided equally between

5220-483: The coast of the Saint Lawrence coast and Chaleur Bay, it was also to be used for military purposes. In 1824, under the command of Governor James Kempt, James Crawford picked up Joseph Bouchette's torch as explorer of the valley's interior and was tasked with finding a suitable path for the important road. In his report, submitted 4 May 1824, he indicates that even if the distance through Lake Matapedia from Métis

5310-466: The depositional fabric of carbonate rocks. Dunham divides the rocks into four main groups based on relative proportions of coarser clastic particles, based on criteria such as whether the grains were originally in mutual contact, and therefore self-supporting, or whether the rock is characterized by the presence of frame builders and algal mats. Unlike the Folk scheme, Dunham deals with the original porosity of

5400-469: The deposits are highly porous, so that they have a spongelike texture, they are typically described as tufa . Secondary calcite deposited by supersaturated meteoric waters ( groundwater ) in caves is also sometimes described as travertine. This produces speleothems , such as stalagmites and stalactites . Coquina is a poorly consolidated limestone composed of abraded pieces of coral , shells , or other fossil debris. When better consolidated, it

5490-406: The earth's oceans are oversaturated with CaCO 3 by a factor of more than six. The failure of CaCO 3 to rapidly precipitate out of these waters is likely due to interference by dissolved magnesium ions with nucleation of calcite crystals, the necessary first step in precipitation. Precipitation of aragonite may be suppressed by the presence of naturally occurring organic phosphates in

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5580-399: The first refers to the grains and the second to the cement. For example, a limestone consisting mainly of ooids, with a crystalline matrix, would be termed an oosparite. It is helpful to have a petrographic microscope when using the Folk scheme, because it is easier to determine the components present in each sample. Robert J. Dunham published his system for limestone in 1962. It focuses on

5670-572: The formation of distinctive minerals from the silica and clay present in the original limestone. Two major classification schemes, the Folk and Dunham, are used for identifying the types of carbonate rocks collectively known as limestone. Robert L. Folk developed a classification system that places primary emphasis on the detailed composition of grains and interstitial material in carbonate rocks . Based on composition, there are three main components: allochems (grains), matrix (mostly micrite), and cement (sparite). The Folk system uses two-part names;

5760-429: The geologic record are called bioherms . Many are rich in fossils, but most lack any connected organic framework like that seen in modern reefs. The fossil remains are present as separate fragments embedded in ample mud matrix. Much of the sedimentation shows indications of occurring in the intertidal or supratidal zones, suggesting sediments rapidly fill available accommodation space in the shelf or platform. Deposition

5850-537: The inner territory of the valley remained unexplored. In 1815, the Lower Canada governor Sir James Kempt sent explorer Joseph Bouchette to the territory of the Matapedia Valley to see to the construction of Kempt Road. This was done in order to connect Métis on the shores of the Saint Lawrence River to Pointe-à-la-Croix near Chaleur Bay. In Topographie du Bas-Canada , Joseph Bouchette wrote that

5940-504: The interior of the valley. At its eastern extremity lies the Saint-Alexis-de-Matapédia parish, which was founded in 1870 by twelve Acadians. In 1860, missionary Georges-Antoine Belcourt was granted a concession for poor families in his parish, prompting him to colonize the Matapedia Valley. Quebecers were generous to the newcomers, and with the financial and material assistance, and with financial and material support,

6030-503: The land to their son Jean-Baptiste Raymond . After some financial trouble, the latter sold the entire seigneurie for 700 pounds to Patrick Langan in 1796. The region remained inhabited by the Mi'kmaqs until 1818, when several Scottish families built houses in Métis , and many loyalists settled on the Restigouche River . These two locations define the limits of the Matapedia Valley. For settlers,

6120-434: The last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly dolomite , a closely related rock, which contains a high percentage of the mineral dolomite , CaMg(CO 3 ) 2 . Magnesian limestone

6210-469: The logging industry. The name Matapedia may derive from the Mi'kmaq word matapegiag , meaning "river junction", from the parts mata (junction) and pegiag (river), referring to the Matapédia River that crosses the town just before its confluence with the Restigouche River . Silas Tertius Rand , a noted linguist and source from the late nineteenth century, indicated that the Mi'kmaq named

6300-459: The main avenue of communication, Route 132 . The city of Amqui is the seat of the RCM and is home to 6,261 people. The Mi'kmaq people first developed the valley around 500 BCE. French-Canadian settlement began in 1833 when Pierre Brochu moved to Lake Matapedia along Kempt Road. Settlers began flocking to the land in the late nineteenth century with the development of land clearing, agriculture, and

6390-511: The mouth of the Mitis River on the St. Lawrence River. Around 500 BC, the Mi'kmaq began to settle further into the valley. On 26 May 1694, the governor of New France , Louis de Buade de Frontenac , granted the seigneurie of Lake Matapeguia, which covers the area around the eponymous lake, to Charles-Nicolas-Joseph D'Amours de Louviers. In violation of laws of the time which required a lord to develop his land, D'Amours never even set foot in

6480-410: The ocean basins, but limestone is rarely preserved in continental slope and deep sea environments. The best environments for deposition are warm waters, which have both a high organic productivity and increased saturation of calcium carbonate due to lower concentrations of dissolved carbon dioxide. Modern limestone deposits are almost always in areas with very little silica-rich sedimentation, reflected in

6570-519: The plateaus of this region. Although visited by just a few tourists, Chic-Choc Mountains became much more popular in the late 1990s as backcountry skiing gained popularity in Eastern Canada. Some of the most popular backcountry skiing areas in the region include Mont Hogs Back, Mont Albert , Champ Mars, Mount Logan , and Mines Madeleine. The mountains near Mont Saint Pierre are a destination for ice climbers. A network of trails, including

6660-530: The public and private sectors. The main agricultural municipalities of the valley are Amqui, Causapscal , Saint-Damase , Val-Brillant , and Saint-Léon-le-Grand . The floor of the valley belongs to the Appalachian rock formation. It is composed primarily of Gaspé feldspar sandstone , Gaspé limestone , and a mixture of sandstone, mudstone , and limestone from the Chaleur Group that date back to

6750-426: The reaction: Fossils are often preserved in exquisite detail as chert. Cementing takes place rapidly in carbonate sediments, typically within less than a million years of deposition. Some cementing occurs while the sediments are still under water, forming hardgrounds . Cementing accelerates after the retreat of the sea from the depositional environment, as rainwater infiltrates the sediment beds, often within just

6840-411: The region was quick to prosper. They were later joined by another 300 Acadians from Prince Edward Island and the Magdalen Islands . The Saint-Alexis-de-Matapédia parish was followed by the neighboring parishes of L'Ascension-de-Patapédia, Matapédia, Saint-André-de-Restigouche and Saint-François-d'Assise, which were also established by the Acadians. The first chapel of Saint-Damase was built in 1879 and

6930-482: The relative purity of most limestones. Reef organisms are destroyed by muddy, brackish river water, and carbonate grains are ground down by much harder silicate grains. Unlike clastic sedimentary rock, limestone is produced almost entirely from sediments originating at or near the place of deposition. Limestone formations tend to show abrupt changes in thickness. Large moundlike features in a limestone formation are interpreted as ancient reefs , which when they appear in

7020-460: The rock. The Dunham scheme is more useful for hand samples because it is based on texture, not the grains in the sample. A revised classification was proposed by Wright (1992). It adds some diagenetic patterns to the classification scheme. Travertine is a term applied to calcium carbonate deposits formed in freshwater environments, particularly waterfalls , cascades and hot springs . Such deposits are typically massive, dense, and banded. When

7110-479: The sediments increases. Chemical compaction takes place by pressure solution of the sediments. This process dissolves minerals from points of contact between grains and redeposits it in pore space, reducing the porosity of the limestone from an initial high value of 40% to 80% to less than 10%. Pressure solution produces distinctive stylolites , irregular surfaces within the limestone at which silica-rich sediments accumulate. These may reflect dissolution and loss of

7200-662: The sediments of the ocean floor abruptly transition from carbonate ooze rich in foraminifera and coccolith remains ( Globigerina ooze) to silicic mud lacking carbonates. In rare cases, turbidites or other silica-rich sediments bury and preserve benthic (deep ocean) carbonate deposits. Ancient benthic limestones are microcrystalline and are identified by their tectonic setting. Fossils typically are foraminifera and coccoliths. No pre-Jurassic benthic limestones are known, probably because carbonate-shelled plankton had not yet evolved. Limestones also form in freshwater environments. These limestones are not unlike marine limestone, but have

7290-464: The valley, nor did he send anyone. He died in 1728 without bequeathing the land to anyone. This is why, at the time of the construction of Kempt Road in 1830, there was no mention of this land, and why everyone believed that they were on the Crown 's land. However, Marie-Françoise Damours de Louvières inherited part of the seigneurie, and went on to wed Jean-Baptiste de Remond Moyse, who willed his share of

7380-533: The water by photosynthesis and thereby decreasing the solubility of calcium carbonate. Limestone shows the same range of sedimentary structures found in other sedimentary rocks. However, finer structures, such as lamination , are often destroyed by the burrowing activities of organisms ( bioturbation ). Fine lamination is characteristic of limestone formed in playa lakes , which lack the burrowing organisms. Limestones also show distinctive features such as geopetal structures , which form when curved shells settle to

7470-553: The water. Although ooids likely form through purely inorganic processes, the bulk of CaCO 3 precipitation in the oceans is the result of biological activity. Much of this takes place on carbonate platforms . The origin of carbonate mud, and the processes by which it is converted to micrite, continue to be a subject of research. Modern carbonate mud is composed mostly of aragonite needles around 5 μm (0.20 mils) in length. Needles of this shape and composition are produced by calcareous algae such as Penicillus , making this

7560-401: The western section from Métis to Lake Matapedia was completed. The first European resident in the Matapedia Valley was French-Canadian Pierre Brochu (1795-1871), who in 1833 settled in present-day Sayabec at the junction of Lake Matapedia and Saint-Pierre river. He assumed the position of guardian along Kempt Road for couriers and travelers. Lake Matapedia was renamed Brochu's Lake until 1871,

7650-602: The world by ice. At that time, the postal service operated via a rudimentary path from the Kamouraska seigneurie to Lake Témiscouata , then following the Madawaska and St. John rivers. The basic path in the Lake Témiscouata area became increasingly inefficient for the region's growing needs, so the idea for a new road via Lake Matapedia was conceived. To be named Kempt Road, the route not only served to connect

7740-521: The year in which Pierre Brochu died. Among the other guardians were Malcolm Fraser, who settled in present-day Saint-Moïse , Georges Brochu, son of Pierre Brochu, who settled at the outflow of Lake Matapedia near present-day Amqui , Georges Lebel who settled in Lac-au-Saumon , Jonathan Noble who took up residence on the site where the Causapscal church is today, and in 1849, Thomas Evans on

7830-625: Was canonically erected in 1884. In the heart of the Seignory of Lac-Matapédia was the Val-Brillant parish, which was canonically erected in 1889, and counted more than 2,200 inhabitants by the 1920s. It was named in honor of Pierre Brillant who is considered the "father of the Valley." Also in 1889, the Amqui parish was canonically erected on the eastern tip of Lake Matapedia and had a population greater than 3,000 by 1920. The Sayabec parish, which

7920-445: Was canonically erected in 1896, developed rapidly and numbered more than five hundred families in the 1920s. During the same year, the Causapscal parish was canonically erected and included more than 2,000 people in the 1920s. The Matapédia parish was canonically erected in 1905. Its erection was delayed due to its inhabitants being primarily Scottish Protestants. In 1907, the parishes of Saint-Léon-le-Grand and Lac-au-Saumon split off from

8010-416: Was likely deposited in pore space between grains, suggesting a high-energy depositional environment that removed carbonate mud. Recrystallized sparite is not diagnostic of depositional environment. Limestone outcrops are recognized in the field by their softness (calcite and aragonite both have a Mohs hardness of less than 4, well below common silicate minerals) and because limestone bubbles vigorously when

8100-439: Was longer, it was easier. However, he goes on to note that the terrain east of Lake Matapedia would be more difficult, even along the river, due to the steepness of the river banks. In his report, Crawford also mentions that there was no pedestrian path in the Matapedia Valley, and that it would be beneficial to the region's population to construct one. Kempt's successor, Aylmer, put the project in place six years later. By 1845, only

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