The Miramichi River / ˌ m ɪr ə m ɪ ˈ ʃ iː / is a river located in the east-central part of New Brunswick , Canada. The river drains into Miramichi Bay in the Gulf of St. Lawrence . The name may have been derived from the Montagnais words "Maissimeu Assi" (meaning Mi'kmaq Land), and it is today the namesake of the Miramichi Herald at the Canadian Heraldic Authority .
122-555: The Miramichi River watershed drains a territory comprising one-quarter of New Brunswick's territory, measuring approximately 13,000 km of which 300 km is an estuarine environment on the inner part of Miramichi Bay . The watershed roughly corresponds to Northumberland County , but also includes sections of Victoria County , Carleton County , and York County and smaller parts of Gloucester County and Sunbury County . The Miramichi River meander length measures approximately 250 km and comprises two important branches,
244-476: A lake or ocean . A basin is separated from adjacent basins by a perimeter, the drainage divide , made up of a succession of elevated features, such as ridges and hills . A basin may consist of smaller basins that merge at river confluences , forming a hierarchical pattern . Other terms for a drainage basin are catchment area , catchment basin , drainage area , river basin , water basin , and impluvium . In North America, they are commonly called
366-484: A sink , which may be a permanent lake, a dry lake , or a point where surface water is lost underground . Drainage basins are similar but not identical to hydrologic units , which are drainage areas delineated so as to nest into a multi-level hierarchical drainage system . Hydrologic units are defined to allow multiple inlets, outlets, or sinks. In a strict sense, all drainage basins are hydrologic units but not all hydrologic units are drainage basins. About 48.71% of
488-414: A watershed , though in other English-speaking places, "watershed" is used only in its original sense, that of the drainage divide line. A drainage basin's boundaries are determined by watershed delineation , a common task in environmental engineering and science. In a closed drainage basin, or endorheic basin , rather than flowing to the ocean, water converges toward the interior of the basin, known as
610-431: A 100 kyr Milankovitch cycle , and so each cyclothem represents a cycle of sea level fall and rise over a 100 kyr period. Coal forms when organic matter builds up in waterlogged, anoxic swamps, known as peat mires, and is then buried, compressing the peat into coal. The majority of Earth's coal deposits were formed during the late Carboniferous and early Permian. The plants from which they formed contributed to changes in
732-481: A defined GSSP. The fusulinid Aljutovella aljutovica can be used to define the base of the Moscovian across the northern and eastern margins of Pangea, however, it is restricted in geographic area, which means it cannot be used for global correlations. The first appearance of the conodonts Declinognathodus donetzianus or Idiognathoides postsulcatus have been proposed as a boundary marking species and potential sites in
854-449: A drainage basin, and there are different ways to interpret that data. In the unlikely event that the gauges are many and evenly distributed over an area of uniform precipitation, using the arithmetic mean method will give good results. In the Thiessen polygon method, the drainage basin is divided into polygons with the rain gauge in the middle of each polygon assumed to be representative for
976-540: A drainage boundary is referred to as watershed delineation . Finding the area and extent of a drainage basin is an important step in many areas of science and engineering. Most of the water that discharges from the basin outlet originated as precipitation falling on the basin. A portion of the water that enters the groundwater system beneath the drainage basin may flow towards the outlet of another drainage basin because groundwater flow directions do not always match those of their overlying drainage network. Measurement of
1098-511: A huge influence on the 20th century environmental movement and shed light on issues in small areas such as Miramichi, New Brunswick. The emergence of the environmental movement in New Brunswick catalyzed involvement from a variety of different social groups to target the issue. Local media outlets, scientists, outdoors enthusiasts and members of the general public got involved. Eventually the federal government placed restrictions on DDT spraying in
1220-431: A shallow, tropical seaway which stretched from Southern California to Alaska. The boundary is within a cyclothem sequence of transgressive limestones and fine sandstones , and regressive mudstones and brecciated limestones. The Moscovian Stage is named after shallow marine limestones and colourful clays found around Moscow, Russia. It was first introduced by Sergei Nikitin in 1890. The Moscovian currently lacks
1342-451: A single sedimentary cycle, with an erosional surface at its base. Whilst individual cyclothems are often only metres to a few tens of metres thick, cyclothem sequences can be many hundreds to thousands of metres thick and contain tens to hundreds of individual cyclothems. Cyclothems were deposited along continental shelves where the very gentle gradient of the shelves meant even small changes in sea level led to large advances or retreats of
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#17328519413291464-624: A tropical wetland environment. Extensive coal deposits developed within the cyclothem sequences that dominated the Pennsylvanian sedimentary basins associated with the growing orogenic belt. Subduction of the Panthalassic oceanic plate along its western margin resulted in the Antler orogeny in the Late Devonian to Early Mississippian. Further north along the margin, slab roll-back , beginning in
1586-423: A variety of methods for reconstructing past atmospheric oxygen levels, including the charcoal record, halite gas inclusions, burial rates of organic carbon and pyrite , carbon isotopes of organic material, isotope mass balance and forward modelling. Depending on the preservation of source material, some techniques represent moments in time (e.g. halite gas inclusions), whilst others have a wider time range (e.g.
1708-725: A warmer climate. This rapid rise in CO 2 may have been due to a peak in pyroclastic volcanism and/or a reduction in burial of terrestrial organic matter. The LPIA peaked across the Carboniferous-Permian boundary. Widespread glacial deposits are found across South America, western and central Africa, Antarctica, Australia, Tasmania, the Arabian Peninsula, India, and the Cimmerian blocks, indicating trans-continental ice sheets across southern Gondwana that reached to sea-level. In response to
1830-462: Is an anadromous fish, that is, one that is hatched and grows briefly in freshwater and then migrates to salt water while immature to grow to maturity, before returning to fresh water to spawn and complete their life cycle. The Miramichi River still maintains a reasonably healthy, self-sustaining run of Atlantic salmon, as well as lesser runs of other anadromous fish such as American shad , smelt , herring and sea-run brook trout . About one-half of
1952-508: Is located in Bed 83 of the sequence of dark grey limestones and shales at the Pengchong section, Guangxi , southern China. It is defined by the first appearance of the fusulinid Eoparastaffella simplex in the evolutionary lineage Eoparastaffella ovalis – Eoparastaffella simplex and was ratified in 2009. The Serpukhovian Stage was proposed in 1890 by Russian stratigrapher Sergei Nikitin . It
2074-517: Is named after the Russian village of Gzhel , near Ramenskoye , not far from Moscow. The name and type locality were defined by Sergei Nikitin in 1890. The Gzhelian currently lacks a defined GSSP. The first appearance of the fusulinid Rauserites rossicus and Rauserites stuckenbergi can be used in the Boreal Sea and Paleo-Tethyan regions but not eastern Pangea or Panthalassa margins. Potential sites in
2196-438: Is named after the city of Serpukhov , near Moscow. currently lacks a defined GSSP. The Visean-Serpukhovian boundary coincides with a major period of glaciation. The resulting sea level fall and climatic changes led to the loss of connections between marine basins and endemism of marine fauna across the Russian margin. This means changes in biota are environmental rather than evolutionary making wider correlation difficult. Work
2318-480: Is referred to as " watershed management ". In Brazil , the National Policy of Water Resources, regulated by Act n° 9.433 of 1997, establishes the drainage basin as the territorial division of Brazilian water management. When a river basin crosses at least one political border, either a border within a nation or an international boundary, it is identified as a transboundary river . Management of such basins becomes
2440-626: Is that a delay between the development of trees with the wood fibre lignin and the subsequent evolution of lignin-degrading fungi gave a period of time where vast amounts of lignin-based organic material could accumulate. Genetic analysis of basidiomycete fungi, which have enzymes capable of breaking down lignin, supports this theory by suggesting this fungi evolved in the Permian. However, significant Mesozoic and Cenozoic coal deposits formed after lignin-digesting fungi had become well established, and fungal degradation of lignin may have already evolved by
2562-600: Is the Dead Sea . Drainage basins have been historically important for determining territorial boundaries, particularly in regions where trade by water has been important. For example, the English crown gave the Hudson's Bay Company a monopoly on the fur trade in the entire Hudson Bay basin, an area called Rupert's Land . Bioregional political organization today includes agreements of states (e.g., international treaties and, within
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#17328519413292684-643: Is underway in the Urals and Nashui, Guizhou Province, southwestern China for a suitable site for the GSSP with the proposed definition for the base of the Serpukhovian as the first appearance of conodont Lochriea ziegleri . The Pennsylvanian was proposed by J.J.Stevenson in 1888, named after the widespread coal-rich strata found across the state of Pennsylvania. The closure of the Rheic Ocean and formation of Pangea during
2806-682: The African Great Lakes , the interiors of Australia and the Arabian Peninsula , and parts in Mexico and the Andes . Some of these, such as the Great Basin, are not single drainage basins but collections of separate, adjacent closed basins. In endorheic bodies of water where evaporation is the primary means of water loss, the water is typically more saline than the oceans. An extreme example of this
2928-792: The Continental Divide , northern Alaska and parts of North Dakota , South Dakota , Minnesota , and Montana in the United States, the north shore of the Scandinavian peninsula in Europe, central and northern Russia, and parts of Kazakhstan and Mongolia in Asia , which totals to about 17% of the world's land. Just over 13% of the land in the world drains to the Pacific Ocean . Its basin includes much of China, eastern and southeastern Russia, Japan,
3050-688: The Gulf of Mexico in the west to Turkey in the east. The orogeny was caused by a series of continental collisions between Laurussia, Gondwana and the Armorican Terrane Assemblage (much of modern-day Central and Western Europe including Iberia ) as the Rheic Ocean closed and Pangea formed. This mountain building process began in the Middle Devonian and continued into the early Permian. The Armorican terranes rifted away from Gondwana during
3172-721: The International Commission on Stratigraphy (ICS) stage, but the Viséan is longer, extending into the lower Serpukhovian . North American geologists recognised a similar stratigraphy but divided it into two systems rather than one. These are the lower carbonate-rich sequence of the Mississippian System and the upper siliciclastic and coal-rich sequence of the Pennsylvanian . The United States Geological Survey officially recognised these two systems in 1953. In Russia, in
3294-681: The Korean Peninsula , most of Indochina, Indonesia and Malaysia, the Philippines, all of the Pacific Islands , the northeast coast of Australia , and Canada and the United States west of the Continental Divide (including most of Alaska), as well as western Central America and South America west of the Andes. The Indian Ocean 's drainage basin also comprises about 13% of Earth's land. It drains
3416-661: The Kuznetsk Basin . The northwest to eastern margins of Siberia were passive margins along the Mongol-Okhotsk Ocean on the far side of which lay Amuria. From the mid Carboniferous, subduction zones with associated magmatic arcs developed along both margins of the ocean. The southwestern margin of Siberia was the site of a long lasting and complex accretionary orogen. The Devonian to early Carboniferous Siberian and South Chinese Altai accretionary complexes developed above an east-dipping subduction zone, whilst further south,
3538-668: The Latin carbō (" coal ") and ferō ("bear, carry"), and refers to the many coal beds formed globally during that time. The first of the modern "system" names, it was coined by geologists William Conybeare and William Phillips in 1822, based on a study of the British rock succession. Carboniferous is the period during which both terrestrial animal and land plant life was well established. Stegocephalia (four-limbed vertebrates including true tetrapods ), whose forerunners ( tetrapodomorphs ) had evolved from lobe-finned fish during
3660-566: The Magnitogorsk island arc , which lay between Kazakhstania and Laurussia in the Ural Ocean , collided with the passive margin of northeastern Laurussia ( Baltica craton ). The suture zone between the former island arc complex and the continental margin formed the Main Uralian Fault , a major structure that runs for more than 2,000 km along the orogen. Accretion of the island arc
3782-653: The Old Red Sandstone , Carboniferous Limestone , Millstone Grit and the Coal Measures . These four units were placed into a formalised Carboniferous unit by William Conybeare and William Phillips in 1822 and then into the Carboniferous System by Phillips in 1835. The Old Red Sandstone was later considered Devonian in age. The similarity in successions between the British Isles and Western Europe led to
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3904-744: The Silurian and Ordovician rocks of the Miramichi Highlands, an extension of the Appalachian Mountains , the tributaries of the Miramichi River flow eastward into the New Brunswick Lowland, which dominates the eastern and central part of the province along the Gulf of St. Lawrence. Erosion has created the "Miramichi River valley" (also shortened to just " Miramichi Valley "), through which
4026-725: The Southwest Miramichi River and the Northwest Miramichi River , each having their respective tributaries. Nearly every bend in the river, from Push and Be Damned Rapids to the Turnip Patch has a distinctive name, reflecting the importance of the river to fishermen, canoeists, and lumbermen. Tides reach upriver in the Miramichi system to Sunny Corner on the Northwest Miramichi and to Renous-Quarryville on
4148-467: The groundwater . A drainage basin is an area of land where all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. Carboniferous The Carboniferous ( / ˌ k ɑːr b ə ˈ n ɪ f ər ə s / KAR -bə- NIF -ər-əs ) is a geologic period and system of the Paleozoic era that spans 60 million years from
4270-747: The 1840s British and Russian geologists divided the Carboniferous into the Lower, Middle and Upper series based on Russian sequences. In the 1890s these became the Dinantian, Moscovian and Uralian stages. The Serpukivian was proposed as part of the Lower Carboniferous, and the Upper Carboniferous was divided into the Moscovian and Gzhelian . The Bashkirian was added in 1934. In 1975, the ICS formally ratified
4392-520: The Bashkirian, the late Moscovian and the latest Kasimovian to mid-Gzhelian are inferred from the disappearance of glacial sediments, the appearance of deglaciation deposits and rises in sea levels. In the early Kasimovian there was short-lived (<1 million years) intense period of glaciation, with atmospheric CO 2 concentration levels dropping as low as 180 ppm. This ended suddenly as a rapid increase in CO 2 concentrations to c. 600 ppm resulted in
4514-726: The Carboniferous Earth's atmosphere, and the coal fueled the Industrial Revolution . During the Pennsylvanian, vast amounts of organic debris accumulated in the peat mires that formed across the low-lying, humid equatorial wetlands of the foreland basins of the Central Pangean Mountains in Laurussia, and around the margins of the North and South China cratons. During glacial periods, low sea levels exposed large areas of
4636-641: The Carboniferous System, with the Mississippian and Pennsylvanian subsystems from the North American timescale, the Tournaisian and Visean stages from the Western European and the Serpukhovian, Bashkirian, Moscovian, Kasimovian and Gzhelian from the Russian. With the formal ratification of the Carboniferous System, the Dinantian, Silesian, Namurian, Westphalian and Stephanian became redundant terms, although
4758-591: The Carboniferous, the Tarim craton lay along the northwestern edge of North China. Subduction along the Kazakhstanian margin of the Turkestan Ocean resulted in collision between northern Tarim and Kazakhstania during the mid Carboniferous as the ocean closed. The South Tian Shan fold and thrust belt , which extends over 2,000 km from Uzbekistan to northwest China, is the remains of this accretionary complex and forms
4880-725: The Early Mississippian, led to the rifting of the Yukon-Tanana terrane and the opening of the Slide Mountain Ocean . Along the northern margin of Laurussia, orogenic collapse of the Late Devonian to Early Mississippian Innuitian orogeny led to the development of the Sverdrup Basin . Much of Gondwana lay in the southern polar region during the Carboniferous. As the plate moved, the South Pole drifted from southern Africa in
5002-509: The Early to Middle Mississippian, carbonate production occurred to depth across the gently dipping continental slopes of Laurussia and North and South China ( carbonate ramp architecture) and evaporites formed around the coastal regions of Laurussia, Kazakhstania, and northern Gondwana. From the late Visean, the cooling climate restricted carbonate production to depths of less than c. 10 m forming carbonate shelves with flat-tops and steep sides. By
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5124-485: The Kasimovian covers a period of globally low sea level, which has resulted in disconformities within many sequences of this age. This has created difficulties in finding suitable marine fauna that can used to correlate boundaries worldwide. The Kasimovian currently lacks a defined GSSP; potential sites in the southern Urals, southwest USA and Nashui, Guizhou Province, southwestern China are being considered. The Gzhelian
5246-476: The Late Ordovician . As they drifted northwards the Rheic Ocean closed in front of them, and they began to collide with southeastern Laurussia in the Middle Devonian. The resulting Variscan orogeny involved a complex series of oblique collisions with associated metamorphism , igneous activity, and large-scale deformation between these terranes and Laurussia, which continued into the Carboniferous. During
5368-635: The Late Pennsylvanian, deformation along the Alleghanian orogen became northwesterly-directed compression . The Uralian orogeny is a north–south trending fold and thrust belt that forms the western edge of the Central Asian Orogenic Belt . The Uralian orogeny began in the Late Devonian and continued, with some hiatuses, into the Jurassic . From the Late Devonian to early Carboniferous,
5490-465: The Miramichi River salmon fishing waters are controlled by private clubs and outfitters, with "public water" that is available to all very limited. Further, all non-resident anglers must hire a registered guide to fish for Atlantic salmon in New Brunswick. Guides can be inquired for in the village of Doaktown and through Dept. of Natural Resources offices. The Miramichi River has a significant environmental history which has brought negative attention to
5612-417: The Miramichi River with saltwater . The estuary comprises the inner portion of Miramichi Bay and is protected from ocean storms in the Gulf of St. Lawrence by barrier islands . The estuary is significant in that it is a highly productive ecosystem , despite its relatively small size. The estuary receives the freshwater discharge from the Miramichi River and its tributaries, mixing with organic materials from
5734-435: The Miramichi area. Assuming the DDT would only harm the budworms, planes kept their spraying jets on over the entire region including over the major waterways. This chemical spraying project adversely affected the river as well as the living things within it, particularly the wild salmon. Soon after the spraying project, mass quantities of dead salmon washed up onto the riverbeds of the Miramichi River. Approximately only 1/3rd of
5856-464: The Northwest and Southwest Miramichi rivers flow. Throughout the course of both branches to Newcastle, New Brunswick, they are framed by heavily forested low hills. The highest peaks in the Miramichi River watershed, include Big Bald Mountain and the Christmas Mountains , extending to 750 m above sea level . Soils in the Miramichi River watershed are typically acidic with shallow topsoil, lending to poor suitability for agriculture. The shorelines of
5978-441: The Paleo-Tethys to the southwest and Panthalassa to the northeast. Cyclothem sediments with coal and evaporites were deposited across the passive margins that surrounded both continents. The Carboniferous climate was dominated by the Late Paleozoic Ice Age (LPIA), the most extensive and longest icehouse period of the Phanerozoic, which lasted from the Late Devonian to the Permian (365 Ma-253 Ma). Temperatures began to drop during
6100-412: The Pennsylvanian, cyclothems were deposited in shallow, epicontinental seas across the tropical regions of Laurussia (present day western and central US, Europe, Russia and central Asia) and the North and South China cratons . The rapid sea levels fluctuations they represent correlate with the glacial cycles of the Late Paleozoic Ice Age. The advance and retreat of ice sheets across Gondwana followed
6222-402: The Pennsylvanian, together with widespread glaciation across Gondwana led to major climate and sea level changes, which restricted marine fauna to particular geographic areas thereby reducing widespread biostratigraphic correlations. Extensive volcanic events associated with the assembling of Pangea means more radiometric dating is possible relative to the Mississippian. The Bashkirian Stage
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#17328519413296344-426: The Period. This was not a steady rise, but included peaks and troughs reflecting the dynamic climate conditions of the time. How the atmospheric oxygen concentrations influenced the large body size of arthropods and other fauna and flora during the Carboniferous is also a subject of ongoing debate. The changing climate was reflected in regional-scale changes in sedimentation patterns. In the relatively warm waters of
6466-430: The Permian. The Kazakhstanian microcontinent is composed of a series of Devonian and older accretionary complexes. It was strongly deformed during the Carboniferous as its western margin collided with Laurussia during the Uralian orogen and its northeastern margin collided with Siberia. Continuing strike-slip motion between Laurussia and Siberia led the formerly elongate microcontinent to bend into an orocline . During
6588-456: The Province of New Brunswick prior to fishing, as special licences, salmon "tags" and permits are required, and certain sections of tributaries and the main river are closed to fishing from time to time to protect salmon brood stocks. The annual salmon runs start in mid-June and continue through late October, when spawning commences in earnest. It is believed that distinct runs of salmon destined for specific tributaries occur at different times of
6710-400: The Southwest Miramichi — a distance of approximately 70 km inland from the Gulf of St. Lawrence . The two branches combine at Newcastle where the river becomes navigable to ocean-going vessels. The estuarine portion of the Miramichi River downriver from Newcastle in the city of Miramichi flows through a drowned river valley. Sea level rise in Miramichi Bay has flooded the mouth of
6832-417: The US, interstate compacts ) or other political entities in a particular drainage basin to manage the body or bodies of water into which it drains. Examples of such interstate compacts are the Great Lakes Commission and the Tahoe Regional Planning Agency . In hydrology , the drainage basin is a logical unit of focus for studying the movement of water within the hydrological cycle . The process of finding
6954-432: The Urals and Nashui, Guizhou Province, southwestern China are being considered. The Kasimovian is the first stage in the Upper Pennsylvanian. It is named after the Russian city of Kasimov , and was originally included as part of Nikitin's 1890 definition of the Moscovian. It was first recognised as a distinct unit by A.P. Ivanov in 1926, who named it the " Tiguliferina " Horizon after a type of brachiopod . The boundary of
7076-431: The Urals and Nashui, Guizhou Province, southwestern China for the GSSP are being considered. The GSSP for the base of the Permian is located in the Aidaralash River valley near Aqtöbe , Kazakhstan and was ratified in 1996. The beginning of the stage is defined by the first appearance of the conodont Streptognathodus postfusus . A cyclothem is a succession of non-marine and marine sedimentary rocks , deposited during
7198-414: The Visean of c. 15.3%, although with large uncertainties; and, pyrite records suggest levels of c. 15% early in the Carboniferous, to over 25% during the Pennsylvanian, before dropping back below 20% towards the end. However, whilst exact numbers vary, all models show an overall increase in atmospheric oxygen levels from a low of between 15-20% at the beginning of the Carboniferous to highs of 25-30% during
7320-406: The Zharma-Saur arc formed along the northeastern margin of Kazakhstania. By the late Carboniferous, all these complexes had accreted to the Siberian craton as shown by the intrusion of post-orogenic granites across the region. As Kazakhstania had already accreted to Laurussia, Siberia was effectively part of Pangea by 310 Ma, although major strike-slip movements continued between it and Laurussia into
7442-477: The average temperature in the tropics c. 24 °C (75 °F) and in polar regions c. -23 °C (-10 °F), whilst during the Early Tournaisian Warm Interval (358-353 Ma) the GAT was c. 22 °C (72 °F), the tropics c. 30 °C (86 °F) and polar regions c. 1.5 °C (35 °F). Overall, for the Ice Age the GAT was c. 17 °C (62 °F), with tropical temperatures c. 26 °C and polar temperatures c. -9.0 °C (16 °F). There are
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#17328519413297564-410: The base of the Carboniferous System, Mississippian Subsystem and Tournaisian Stage is located at the La Serre section in Montagne Noire , southern France. It is defined by the first appearance of the conodont Siphonodella sulcata within the evolutionary lineage from Siphonodella praesulcata to Siphonodella sulcata . This was ratified by the ICS in 1990. However, in 2006 further study revealed
7686-406: The basin, it can form tributaries that change the structure of the land. There are three different main types, which are affected by the rocks and ground underneath. Rock that is quick to erode forms dendritic patterns, and these are seen most often. The two other types of patterns that form are trellis patterns and rectangular patterns. Rain gauge data is used to measure total precipitation over
7808-433: The beginning of the Period to highs of 25-30%. The development of a Carboniferous chronostratigraphic timescale began in the late 18th century. The term "Carboniferous" was first used as an adjective by Irish geologist Richard Kirwan in 1799 and later used in a heading entitled "Coal-measures or Carboniferous Strata" by John Farey Sr. in 1811. Four units were originally ascribed to the Carboniferous, in ascending order,
7930-410: The charcoal record and pyrite). Results from these different methods for the Carboniferous vary. For example: the increasing occurrence of charcoal produced by wildfires from the Late Devonian into the Carboniferous indicates increasing oxygen levels, with calculations showing oxygen levels above 21% for most of the Carboniferous; halite gas inclusions from sediments dated 337-335 Ma give estimates for
8052-402: The city of Visé , Liège Province , Belgium. In 1967, the base of the Visean was officially defined as the first black limestone in the Leffe facies at the Bastion Section in the Dinant Basin . These changes are now thought to be ecologically driven rather than caused by evolutionary change, and so this has not been used as the location for the GSSP. Instead, the GSSP for the base of the Visean
8174-411: The complexity of the geology. The ICS subdivisions from youngest to oldest are as follows: The Mississippian was proposed by Alexander Winchell in 1870 named after the extensive exposure of lower Carboniferous limestone in the upper Mississippi River valley. During the Mississippian, there was a marine connection between the Paleo-Tethys and Panthalassa through the Rheic Ocean resulting in
8296-437: The continental shelves. Major river channels, up to several kilometres wide, stretched across these shelves feeding a network of smaller channels, lakes and peat mires. These wetlands were then buried by sediment as sea levels rose during interglacials . Continued crustal subsidence of the foreland basins and continental margins allowed this accumulation and burial of peat deposits to continue over millions of years resulting in
8418-407: The development of a common European timescale with the Carboniferous System divided into the lower Dinantian , dominated by carbonate deposition and the upper Silesian with mainly siliciclastic deposition. The Dinantian was divided into the Tournaisian and Viséan stages. The Silesian was divided into the Namurian , Westphalian and Stephanian stages. The Tournaisian is the same length as
8540-430: The discharge of water from a basin may be made by a stream gauge located at the basin's outlet. Depending on the conditions of the drainage basin, as rainfall occurs some of it seeps directly into the ground. This water will either remain underground, slowly making its way downhill and eventually reaching the basin, or it will permeate deeper into the soil and consolidate into groundwater aquifers. As water flows through
8662-441: The drainage area is dependent on the soil type. Certain soil types such as sandy soils are very free-draining, and rainfall on sandy soil is likely to be absorbed by the ground. However, soils containing clay can be almost impermeable and therefore rainfall on clay soils will run off and contribute to flood volumes. After prolonged rainfall even free-draining soils can become saturated , meaning that any further rainfall will reach
8784-692: The drainage basin to the mouth, and may accumulate there, disturbing the natural mineral balance. This can cause eutrophication where plant growth is accelerated by the additional material. Because drainage basins are coherent entities in a hydrological sense, it has become common to manage water resources on the basis of individual basins. In the U.S. state of Minnesota , governmental entities that perform this function are called " watershed districts ". In New Zealand, they are called catchment boards. Comparable community groups based in Ontario, Canada, are called conservation authorities . In North America, this function
8906-526: The early Carboniferous Kanimblan Orogeny . Continental arc magmatism continued into the late Carboniferous and extended round to connect with the developing proto-Andean subduction zone along the western South American margin of Gondwana. Shallow seas covered much of the Siberian craton in the early Carboniferous. These retreated as sea levels fell in the Pennsylvanian and as the continent drifted north into more temperate zones extensive coal deposits formed in
9028-580: The early Carboniferous in North China. However, bauxite deposits immediately above the regional mid Carboniferous unconformity indicate warm tropical conditions and are overlain by cyclothems including extensive coals. South China and Annamia (Southeast Asia) rifted from Gondwana during the Devonian. During the Carboniferous, they were separated from each other and North China by the Paleoasian Ocean with
9150-618: The early Carboniferous to eastern Antarctica by the end of the period. Glacial deposits are widespread across Gondwana and indicate multiple ice centres and long-distance movement of ice. The northern to northeastern margin of Gondwana (northeast Africa, Arabia, India and northeastern West Australia) was a passive margin along the southern edge of the Paleo-Tethys with cyclothem deposition including, during more temperate intervals, coal swamps in Western Australia. The Mexican terranes along
9272-821: The eastern coast of Africa, the coasts of the Red Sea and the Persian Gulf , the Indian subcontinent , Burma, and most parts of Australia . The five largest river basins (by area), from largest to smallest, are those of the Amazon (7 million km ), the Congo (4 million km ), the Nile (3.4 million km ), the Mississippi (3.22 million km ), and the Río de la Plata (3.17 million km ). The three rivers that drain
9394-647: The end of the Devonian Period 358.9 Ma (million years ago) to the beginning of the Permian Period, 298.9 Ma. It is the fifth and penultimate period of the Paleozoic era and the fifth period of the Phanerozoic eon . In North America , the Carboniferous is often treated as two separate geological periods, the earlier Mississippian and the later Pennsylvanian . The name Carboniferous means " coal -bearing", from
9516-523: The end of the Carboniferous, extension and rifting across the northern margin of Gondwana led to the breaking away of the Cimmerian Terrane during the early Permian and the opening of the Neo-Tethys Ocean . Along the southeastern and southern margin of Gondwana (eastern Australia and Antarctica), northward subduction of Panthalassa continued. Changes in the relative motion of the plates resulted in
9638-451: The end of the Devonian, even if the specific enzymes used by basidiomycetes had not. The second theory is that the geographical setting and climate of the Carboniferous were unique in Earth's history: the co-occurrence of the position of the continents across the humid equatorial zone, high biological productivity, and the low-lying, water-logged and slowly subsiding sedimentary basins that allowed
9760-536: The estuarine portion of the Miramichi River exposes newer rocks belonging to the Carboniferous period and underlay the sandy topsoil, however some coastal land is low lying and suffers poor drainage. Sandstone rocks are visible along the river banks. The Miramichi River and its tributaries originally supported one of the largest populations of Atlantic salmon ( Salmo salar ) in North America. The Atlantic salmon
9882-475: The formation of thick and widespread coal formations. During the warm interglacials, smaller coal swamps with plants adapted to the temperate conditions formed on the Siberian craton and the western Australian region of Gondwana. There is ongoing debate as to why this peak in the formation of Earth's coal deposits occurred during the Carboniferous. The first theory, known as the delayed fungal evolution hypothesis,
10004-567: The greatest portion of western Sub-Saharan Africa , as well as Western Sahara and part of Morocco . The two major mediterranean seas of the world also flow to the Atlantic. The Caribbean Sea and Gulf of Mexico basin includes most of the U.S. interior between the Appalachian and Rocky Mountains , a small part of the Canadian provinces of Alberta and Saskatchewan , eastern Central America ,
10126-435: The ground and along rivers it can pick up nutrients , sediment , and pollutants . With the water, they are transported towards the outlet of the basin, and can affect the ecological processes along the way as well as in the receiving water body . Modern use of artificial fertilizers , containing nitrogen (as nitrates ), phosphorus , and potassium , has affected the mouths of drainage basins. The minerals are carried by
10248-744: The ground at its terminus, the area can go by several names, such playa, salt flat, dry lake , or alkali sink . The largest endorheic basins are in Central Asia , including the Caspian Sea , the Aral Sea , and numerous smaller lakes. Other endorheic regions include the Great Basin in the United States, much of the Sahara Desert , the drainage basin of the Okavango River ( Kalahari Basin ), highlands near
10370-451: The hatchlings and 1/6th of the already established salmon population survived. The spraying affected the salmon indirectly as well by eliminating the insect population which the fish depended on as a food source. Combating the spruce budworm problem by spraying DDT ultimately altered the entire ecosystem of the Miramichi River. This event was documented in a famous environmental text, Silent Spring by Rachel Carson , in 1962. Silent Spring had
10492-572: The islands of the Caribbean and the Gulf, and a small part of northern South America. The Mediterranean Sea basin, with the Black Sea , includes much of North Africa , east-central Africa (through the Nile River ), Southern , Central, and Eastern Europe , Turkey , and the coastal areas of Israel , Lebanon , and Syria . The Arctic Ocean drains most of Western Canada and Northern Canada east of
10614-456: The late Carboniferous. Land arthropods such as arachnids (e.g. trigonotarbids and Pulmonoscorpius ), myriapods (e.g. Arthropleura ) and especially insects (particularly flying insects ) also underwent a major evolutionary radiation during the late Carboniferous. Vast swaths of forests and swamps covered the land, which eventually became the coal beds characteristic of the Carboniferous stratigraphy evident today. The later half of
10736-570: The late Devonian with a short-lived glaciation in the late Famennian through Devonian–Carboniferous boundary, before the Early Tournaisian Warm Interval. Following this, a reduction in atmospheric CO 2 levels, caused by the increased burial of organic matter and widespread ocean anoxia led to climate cooling and glaciation across the south polar region. During the Visean Warm Interval glaciers nearly vanished retreating to
10858-526: The latter three are still in common use in Western Europe. Stages can be defined globally or regionally. For global stratigraphic correlation, the ICS ratify global stages based on a Global Boundary Stratotype Section and Point (GSSP) from a single formation (a stratotype ) identifying the lower boundary of the stage. Only the boundaries of the Carboniferous System and three of the stage bases are defined by global stratotype sections and points because of
10980-432: The majority of a cyclothem sequence occurred during falling sea levels, when rates of erosion were high, meaning they were often periods of non-deposition. Erosion during sea level falls could also result in the full or partial removal of previous cyclothem sequences. Individual cyclothems are generally less than 10 m thick because the speed at which sea level rose gave only limited time for sediments to accumulate. During
11102-593: The mid Carboniferous, the South American sector of Gondwana collided obliquely with Laurussia's southern margin resulting in the Ouachita orogeny. The major strike-slip faulting that occurred between Laurussia and Gondwana extended eastwards into the Appalachian Mountains where early deformation in the Alleghanian orogeny was predominantly strike-slip. As the West African sector of Gondwana collided with Laurussia during
11224-458: The most water, from most to least, are the Amazon, Ganges , and Congo rivers. Endorheic basin are inland basins that do not drain to an ocean. Endorheic basins cover around 18% of the Earth's land. Some endorheic basins drain to an Endorheic lake or Inland sea . Many of these lakes are ephemeral or vary dramatically in size depending on climate and inflow. If water evaporates or infiltrates into
11346-451: The near worldwide distribution of marine faunas and so allowing widespread correlations using marine biostratigraphy . However, there are few Mississippian volcanic rocks , and so obtaining radiometric dates is difficult. The Tournaisian Stage is named after the Belgian city of Tournai . It was introduced in scientific literature by Belgian geologist André Dumont in 1832. The GSSP for
11468-505: The northwestern Gondwana margin, were affected by the subduction of the Rheic Ocean. However, they lay to west of the Ouachita orogeny and were not impacted by continental collision but became part of the active margin of the Pacific. The Moroccan margin was affected by periods of widespread dextral strike-slip deformation, magmatism and metamorphism associated with the Variscan orogeny. Towards
11590-490: The old river channel that forms the navigation channel for ocean-going ships heading to ports at Chatham and Newcastle , to the winter covering of sea ice that encases the entire estuary. The inner bay measures only 4 m deep on average, with the navigation channel measuring only 6–10 m, resulting in significant warming of estuarine waters during the summer months. The diurnal tide cycle ranges only 1 m on average. Important tributaries include: Miramichi River Rising in
11712-426: The peat mires. As fully marine conditions were established, limestones succeeded these marginal marine deposits. The limestones were in turn overlain by deep water black shales as maximum sea levels were reached. Ideally, this sequence would be reversed as sea levels began to fall again; however, sea level falls tend to be protracted, whilst sea level rises are rapid, ice sheets grow slowly but melt quickly. Therefore,
11834-454: The period experienced glaciations , low sea level, and mountain building as the continents collided to form Pangaea . A minor marine and terrestrial extinction event, the Carboniferous rainforest collapse , occurred at the end of the period, caused by climate change. Atmospheric oxygen levels, originally thought to be consistently higher than today throughout the Carboniferous, have been shown to be more variable, increasing from low levels at
11956-488: The preceding Devonian period, became pentadactylous during the Carboniferous. The period is sometimes called the Age of Amphibians because of the diversification of early amphibians such as the temnospondyls , which became dominant land vertebrates, as well as the first appearance of amniotes including synapsids (the clade to which modern mammals belong) and sauropsids (which include modern reptiles and birds) during
12078-459: The presence of Siphonodella sulcata below the boundary, and the presence of Siphonodella praesulcata and Siphonodella sulcata together above a local unconformity . This means the evolution of one species to the other, the definition of the boundary, is not seen at the La Serre site making precise correlation difficult. The Viséan Stage was introduced by André Dumont in 1832 and is named after
12200-877: The proto-Andes in Bolivia and western Argentina and the Pan-African mountain ranges in southeastern Brazil and southwest Africa. The main phase of the LPIA (c. 335-290 Ma) began in the late Visean, as the climate cooled and atmospheric CO 2 levels dropped. Its onset was accompanied by a global fall in sea level and widespread multimillion-year unconformities. This main phase consisted of a series of discrete several million-year-long glacial periods during which ice expanded out from up to 30 ice centres that stretched across mid- to high latitudes of Gondwana in eastern Australia, northwestern Argentina, southern Brazil, and central and Southern Africa. Isotope records indicate this drop in CO 2 levels
12322-403: The province of New Brunswick. Known as one of the greatest salmon streams in North America, this waterway is frequented for both recreational and subsistence fishing. In the early 1950s the Miramichi area began having a spruce budworm problem which was affecting the trees purposed for the local pulp and paper industry. To combat the issue, a solution of the chemical DDT was sprayed aerially over
12444-451: The province. This series of events ultimately demonstrated that industrial development has negative impacts on the environment. 47°1′8.6″N 65°31′32.1″W / 47.019056°N 65.525583°W / 47.019056; -65.525583 Drainage basin A drainage basin is an area of land in which all flowing surface water converges to a single point, such as a river mouth , or flows into another body of water , such as
12566-418: The rainfall on the area of land included in its polygon. These polygons are made by drawing lines between gauges, then making perpendicular bisectors of those lines form the polygons. The isohyetal method involves contours of equal precipitation are drawn over the gauges on a map. Calculating the area between these curves and adding up the volume of water is time-consuming. Isochrone maps can be used to show
12688-625: The responsibility of the countries sharing it. Nile Basin Initiative , OMVS for Senegal River , Mekong River Commission are a few examples of arrangements involving management of shared river basins. Management of shared drainage basins is also seen as a way to build lasting peaceful relationships among countries. The catchment is the most significant factor determining the amount or likelihood of flooding . Catchment factors are: topography , shape, size, soil type, and land use (paved or roofed areas). Catchment topography and shape determine
12810-461: The river rather than being absorbed by the ground. If the surface is impermeable the precipitation will create surface run-off which will lead to higher risk of flooding; if the ground is permeable, the precipitation will infiltrate the soil. Land use can contribute to the volume of water reaching the river, in a similar way to clay soils. For example, rainfall on roofs, pavements , and roads will be collected by rivers with almost no absorption into
12932-622: The sea. Cyclothem lithologies vary from mudrock and carbonate-dominated to coarse siliciclastic sediment-dominated sequences depending on the paleo-topography, climate and supply of sediments to the shelf. The main period of cyclothem deposition occurred during the Late Paleozoic Ice Age from the Late Mississippian to early Permian, when the waxing and waning of ice sheets led to rapid changes in eustatic sea level . The growth of ice sheets led global sea levels to fall as water
13054-418: The speed with which the runoff reaches a river. A long thin catchment will take longer to drain than a circular catchment. Size will help determine the amount of water reaching the river, as the larger the catchment the greater the potential for flooding. It is also determined on the basis of length and width of the drainage basin. Soil type will help determine how much water reaches the river. The runoff from
13176-514: The sport catch of Atlantic salmon in North America are landed on the Miramichi River and its tributaries currently. Atlantic salmon fishing is restricted to fly fishing only and all large salmon caught must be released alive to protect the spawning population. Since this fishery is highly regulated, all anglers should contact the New Brunswick Dept. of Natural Resources to obtain the specific rules and regulations for each river and tributary in
13298-406: The surrounding shorelines and the saltwater inundation from the Gulf of St. Lawrence, itself an estuary and the largest on the planet. The estuary is a highly dynamic environment, ranging from the high outflows of freshwater during the spring freshet , to the low outflow and rising saltwater content during the summer period, to fall ocean storms and nor'easters that reshape the barrier islands and
13420-497: The suture between Kazakhstania and Tarim. A continental magmatic arc above a south-dipping subduction zone lay along the northern North China margin, consuming the Paleoasian Ocean. Northward subduction of the Paleo-Tethys beneath the southern margins of North China and Tarim continued during the Carboniferous, with the South Qinling block accreted to North China during the mid to late Carboniferous. No sediments are preserved from
13542-410: The thick accumulation of peat were sufficient to account for the peak in coal formation. During the Carboniferous, there was an increased rate in tectonic plate movements as the supercontinent Pangea assembled. The continents themselves formed a near circle around the opening Paleo-Tethys Ocean, with the massive Panthalassic Ocean beyond. Gondwana covered the south polar region. To its northwest
13664-415: The time taken for rain to reach the river, while catchment size, soil type, and development determine the amount of water to reach the river. Generally, topography plays a big part in how fast runoff will reach a river. Rain that falls in steep mountainous areas will reach the primary river in the drainage basin faster than flat or lightly sloping areas (e.g., > 1% gradient). Shape will contribute to
13786-477: The time taken for runoff water within a drainage basin to reach a lake, reservoir or outlet, assuming constant and uniform effective rainfall. Drainage basins are the principal hydrologic unit considered in fluvial geomorphology . A drainage basin is the source for water and sediment that moves from higher elevation through the river system to lower elevations as they reshape the channel forms. Drainage basins are important in ecology . As water flows over
13908-544: The uplift and erosion of the more mafic basement rocks of the Central Pangea Mountains at this time, CO 2 levels dropped as low as 175 ppm and remained under 400 ppm for 10 Ma. Temperatures across the Carboniferous reflect the phases of the LPIA. At the extremes, during the Permo-Carboniferous Glacial Maximum (299-293 Ma) the global average temperature (GAT) was c. 13 °C (55 °F),
14030-641: The world's land drains to the Atlantic Ocean . In North America , surface water drains to the Atlantic via the Saint Lawrence River and Great Lakes basins, the Eastern Seaboard of the United States, the Canadian Maritimes , and most of Newfoundland and Labrador . Nearly all of South America east of the Andes also drains to the Atlantic, as does most of Western and Central Europe and
14152-566: The year, with those fish headed for the upper reaches of the watershed entering the river earlier than those that spawn in the lower tributaries. Popular salmon flies on the Miramichi River include the Black Bear series, the Cosseboom series, Butterfly, Oriole, and the Blackville Special. Deerhair flies such as the "Buck Bug" or the "Green Machine" are also quite successful. Major portions of
14274-487: Was Laurussia. These two continents slowly collided to form the core of Pangea. To the north of Laurussia lay Siberia and Amuria . To the east of Siberia, Kazakhstania , North China and South China formed the northern margin of the Paleo-Tethys, with Annamia laying to the south. The Central Pangean Mountains were formed during the Variscan - Alleghanian - Ouachita orogeny. Today their remains stretch over 10,000 km from
14396-500: Was complete by the Tournaisian, but subduction of the Ural Ocean between Kazakhstania and Laurussia continued until the Bashkirian when the ocean finally closed and continental collision began. Significant strike-slip movement along this zone indicates the collision was oblique. Deformation continued into the Permian and during the late Carboniferous and Permian the region was extensively intruded by granites . The Laurussian continent
14518-557: Was formed by the collision between Laurentia , Baltica and Avalonia during the Devonian. At the beginning of the Carboniferous, some models show it at the equator, whilst others place it further south. In either case, the continent drifted northwards, reaching low latitudes in the northern hemisphere by the end of the Period. The Central Pangean Mountain drew in moist air from the Paleo-Tethys Ocean resulting in heavy precipitation and
14640-646: Was lock away in glaciers. Falling sea levels exposed large tracts of the continental shelves across which river systems eroded channels and valleys and vegetation broke down the surface to form soils . The non-marine sediments deposited on this erosional surface form the base of the cyclothem. As sea levels began to rise, the rivers flowed through increasingly water-logged landscapes of swamps and lakes. Peat mires developed in these wet and oxygen-poor conditions, leading to coal formation. With continuing sea level rise, coastlines migrated landward and deltas , lagoons and esturaries developed; their sediments deposited over
14762-564: Was proposed by Russian stratigrapher Sofia Semikhatova in 1934. It was named after Bashkiria , the then Russian name of the republic of Bashkortostan in the southern Ural Mountains of Russia. The GSSP for the base of the Pennsylvanian Subsystem and Bashkirian Stage is located at Arrow Canyon in Nevada , US and was ratified in 1996. It is defined by the first appearance of the conodont Declinognathodus noduliferus . Arrow Canyon lay in
14884-455: Was triggered by tectonic factors with increased weathering of the growing Central Pangean Mountains and the influence of the mountains on precipitation and surface water flow. Closure of the oceanic gateway between the Rheic and Tethys oceans in the early Bashkirian also contributed to climate cooling by changing ocean circulation and heat flow patterns. Warmer periods with reduced ice volume within
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