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81-591: Neshaminy Creek is a 40.7-mile-long (65.5 km) stream that runs entirely through Bucks County , Pennsylvania , rising south of the borough of Chalfont , where its north and west branches join. Neshaminy Creek flows southeast toward Bristol Township and Bensalem Township to its confluence with the Delaware River . The name "Neshaminy" originates with the Lenni Lenape and is thought to mean "place where we drink twice". This phenomenon refers to

162-496: A chimera consisting of coelacanth and Tanytrachelos fossils. Has also been considered a synonym of Tanytrachelos . Rhabdopelix R. longispinis Gwynedd Isolated vertebrae and other remains, now lost A dubious reptile, likely a chimera consisting of Tanytrachelos , Icarosaurus , and/or fish fossils. Diplurus Lysorocephalus L. gwynnedensis Gwynedd A partial skull A dubious fish likely synonymous with Turseodus . Originally misidentified as

243-572: A flooding threat to neighboring areas in times of rapid downpours. The waters of the creek have been known to rise more than 10 feet (3 m) above their normal level during severe storms, such as Hurricane Floyd , which hit the area on September 16, 1999. In 2005, the Natural Resources Conservation Service earmarked $ 3 million for flood mitigation programs along the Neshaminy Creek. The creek

324-399: A lysorophian amphibian. Rabdiolepis R. gwyneddensis Gwynedd A partial skeleton A dubious coelacanth, likely synonymous with Diplurus or Pariostegus . Gwyneddichnium G. majore Rhynchosauroides Grey to black laminated mudstone (shale) was deposited in long-lasting perennial lakes. Some of the laminae are graded due to their sediment settling out after

405-403: A bed armor layer, and other depositional features, plus well defined banks due to bank erosion, are good identifiers when assessing for perennial streams. Particle size will help identify a perennial stream. Perennial streams cut through the soil profile, which removes fine and small particles. By assessing areas for relatively coarse material left behind in the stream bed and finer sediments along

486-543: A carbonate or silicate matrix. This type of mudstone formed on dry lakes (playas) which constantly redeveloped mudcracks as they were hydrated and dried out multiple times. Vesicles can occur in breccia fabric which dried quickly enough to trap air bubbles without collapsing. Vesicular massive mudstone is more chaotic in structure, dominated by numerous vesicles and thin, jagged cracks. The playas responsible for vesicular massive mudstone were much drier than their brecciated equivalent. Peloidal or efflorescent massive mudstone

567-658: A continuous aquatic habitat until they reach maturity. Crayfish and other crustaceans , snails , bivalves (clams), and aquatic worms also indicate the stream is perennial. These require a persistent aquatic environment for survival. Fish and amphibians are secondary indicators in assessment of a perennial stream because some fish and amphibians can inhabit areas without persistent water regime. When assessing for fish, all available habitat should be assessed: pools, riffles, root clumps and other obstructions. Fish will seek cover if alerted to human presence, but should be easily observed in perennial streams. Amphibians also indicate

648-470: A continuous or intermittent stream. The same non-perennial channel might change characteristics from intermittent to ephemeral over its course. Washes can fill up quickly during rains, and there may be a sudden torrent of water after a thunderstorm begins upstream, such as during monsoonal conditions. In the United States, an intermittent or seasonal stream is one that only flows for part of

729-615: A creek, especially one that is fed by a spring or seep . It is usually small and easily forded . A brook is characterised by its shallowness. A creek ( / k r iː k / ) or crick ( / k r ɪ k / ): In hydrography, gut is a small creek; this is seen in proper names in eastern North America from the Mid-Atlantic states (for instance, The Gut in Pennsylvania, Ash Gut in Delaware, and other streams) down into

810-552: A different kind of crystal structure occurring in the Lockatong Formation. They involve blade-like cavities (perhaps originally from sodium carbonate ) which have been filled with crystals of various other minerals. Calcite, analcime, albite, dolomite , and potassium feldspar are all known to occur within Lockatong crystal clasts. Although gypsum is abundant in the crystal clasts of the overlying Passaic Formation, it

891-422: A drainage network. Although each tributary has its own source, international practice is to take the source farthest from the river mouth as the source of the entire river system, from which the most extended length of the river measured as the starting point is taken as the length of the whole river system, and that furthest starting point is conventionally taken as the source of the whole river system. For example,

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972-518: A lakebed. Extensive stacks of this sandstone type indicate rising and falling lake water levels, inducing the deltas to shift and overlap older sediments. Sheet-like deltaic sandstones also have climbing ripples, but their layers are at a much lower angle than clinoform deltaic sandstone. They are often interbedded with mudcracked mudstone, typically vesicle-rich thin-bedded mudstone. The deltas which form these kinds of sandstone were low-relief temporary deltas that manifested during sheet flood events. Both

1053-540: A larger stream. Common terms for individual river distributaries in English-speaking countries are arm and channel . There are a number of regional names for a stream. A stream's source depends on the surrounding landscape and its function within larger river networks. While perennial and intermittent streams are typically supplied by smaller upstream waters and groundwater, headwater and ephemeral streams often derive most of their water from precipitation in

1134-727: A layer of limestone . East of Chalfont, the Neshaminy flows into the Stockton Formation , laid during the Triassic, consisting of arkosic sandstone, sandstone, shale, siltstone, and mudstone. It flows generally along the Stockton and Lockatong transition until the Neshaminy palisades , where it turns west, then in a few miles turns south into a region of felsic gneiss , which contains quartz , microcline , pyroxene , and biotite . After passing Oakford, it passes through

1215-404: A path into mines or other underground chambers. According to official U.S. definitions, the channels of intermittent streams are well-defined, as opposed to ephemeral streams, which may or may not have a defined channel, and rely mainly on storm runoff, as their aquatic bed is above the water table . An ephemeral stream does not have the biological, hydrological, and physical characteristics of

1296-412: A perennial stream and include tadpoles , frogs , salamanders , and newts . These amphibians can be found in stream channels, along stream banks, and even under rocks. Frogs and tadpoles usually inhabit shallow and slow moving waters near the sides of stream banks. Frogs will typically jump into water when alerted to human presence. Well defined river beds composed of riffles, pools, runs, gravel bars,

1377-483: A perennial stream, fine sediment may cling to riparian plant stems and tree trunks. Organic debris drift lines or piles may be found within the active overbank area after recent high flow. Streams, headwaters, and streams flowing only part of the year provide many benefits upstream and downstream. They defend against floods, remove contaminants, recycle nutrients that are potentially dangerous as well as provide food and habitat for many forms of fish. Such streams also play

1458-570: A region of Pensauken and Bridgeton Formations , from the Tertiary , but it has eroded through it to the underlying Wissahickon Formation. Both formations consist of quartz sand. Finally, the Neshaminy passes through the Trenton gravel formation , from the Quaternary , which is sand and clay -silt where it meets the Delaware River . Like other rivers and streams, the Neshaminy Creek poses

1539-407: A scalloped appearance where their edges peel upwards above the mudcracks. Red to grey massive mudstone has no discernable layers. Almost all massive mudstone develops mudcracks, indicating dry conditions above water most of the time. Brecciated massive mudstone is heavily cracked in multiple directions. It has been described as a "breccia fabric": a patchwork of angular mud fragments held together by

1620-616: A section of the creek known as the Neshaminy Palisades, where the course of the water slows and changes direction at almost a right angle, nearly forcing the water back upon itself. These palisades are located in Dark Hollow Park, operated by the county, and are flanked by Warwick Township to the south and Buckingham Township to the north. The watershed of the Neshaminy Creek covers an area of approximately 236 square miles (610 km), 86 percent of which

1701-406: A slow-moving wetted channel or stagnant area. This is evidence that iron-oxidizing bacteria are present, indicating persistent expression of oxygen-depleted ground water. In a forested area, leaf and needle litter in the stream channel is an additional indicator. Accumulation of leaf litter does not occur in perennial streams since such material is continuously flushed. In the adjacent overbank of

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1782-612: A small deposit of mafic gneiss, from the Precambrian , which contains calcic plagioclase , hypersthene or augite , quartz, and hornblende . Next, the stream passes into the Wissahickon Formation (lower Paleozoic ), a schist which has metamorphosed into a facies , containing garnet , staurolite , kyanite , and sillimanite . The Wissahickon also contains oligoclase - mica schist, hornblende and augen gneiss', and some feldspar . It then passes through

1863-503: A small portion of the basin's area. The rocks making up the clasts of Newark conglomerate include dolomite , limestone, gneiss , granite , quartzite , and older Devonian conglomerate from the surrounding mountains. At their maximum size, conglomerate clasts are boulders up to half a meter across, but most clasts are much smaller. Large pebbles and cobbles are typically supported in distinct sandstone lenses with convex upper margins and flat lower margins. The largest clasts are found near

1944-486: A stream as intermittent, "showing interruptions in time or space". Generally, streams that flow only during and immediately after precipitation are termed ephemeral . There is no clear demarcation between surface runoff and an ephemeral stream, and some ephemeral streams can be classed as intermittent—flow all but disappearing in the normal course of seasons but ample flow (backups) restoring stream presence — such circumstances are documented when stream beds have opened up

2025-424: A stream is a critical factor in determining its character and is entirely determined by its base level of erosion. The base level of erosion is the point at which the stream either enters the ocean, a lake or pond, or enters a stretch in which it has a much lower gradient, and may be specifically applied to any particular stretch of a stream. In geological terms, the stream will erode down through its bed to achieve

2106-524: A thin layer called sheet wash, combined with a network of tiny rills, which together form the sheet runoff; when this water is focused in a channel, a stream is born. Some rivers and streams may begin from lakes or ponds. Freshwater's primary sources are precipitation and mountain snowmelt. However, rivers typically originate in the highlands, and are slowly created by the erosion of mountain snowmelt into lakes or rivers. Rivers usually flow from their source topographically, and erode as they pass until they reach

2187-488: A turbidity flow. Others have a lenticular or "pinch-and-swell" shape (with alternating narrow and elliptical cross-sections), which results from the motion of waves at the water surface. Small burrows and minor sediment deformation are also known to occur. However, these shales and their layers become finer, flatter, and less disturbed as the lakes deepen. They also lose oxygen and acquire higher concentrations of dark organic material and carbonate. The finest shales formed in

2268-489: A village of the Lenape, since native people drink from a spring whenever available rather than from a stream. The location of the springs is unknown, but may have been two springs extant many years ago, not far from the confluence of the north and west branches. One was known at the time as the 'Great Spring' and the other much smaller about 300 feet (91 m) away and was said to have been near an old Indian trail. The Neshaminy

2349-627: A vital role in preserving our drinking water quality and supply, ensuring a steady flow of water to surface waters and helping to restore deep aquifers. The extent of land basin drained by a stream is termed its drainage basin (also known in North America as the watershed and, in British English, as a catchment). A basin may also be composed of smaller basins. For instance, the Continental Divide in North America divides

2430-435: Is a stream that branches off and flows away from a main stream channel, and the phenomenon is known as river bifurcation . Distributaries are common features of river deltas , and are often found where a valleyed stream enters wide flatlands or approaches the coastal plains around a lake or an ocean . They can also occur inland, on alluvial fans , or where a tributary stream bifurcates as it nears its confluence with

2511-469: Is absent in the Lockatong Formation. Some crystal clasts grow perpendicular to the layers, often sending out multiple branches as they radiate from a bedding plane. These radiating crystal clasts typically form in transgressing shallow lake mudstones, as saline waters penetrate the lakebed and promote crystal growth. Most crystal clasts are more random in orientation and distribution. Random crystal clasts are typically graded, growing larger and more euhedral

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2592-412: Is indicative of a climate with high evaporation rates. More recent studies suggest that the Lockatong was a highly turbulent environment, akin to the modern Salton Sea , that was frequently subjected to high wind events that overturned the lake waters, which depleted the dissolved oxygen in the water or made the lake more toxic. These environmental shifts led to massive fish kills that accumulated on

2673-588: Is located in Bucks County and 14 percent in Montgomery County . It is part of the greater Delaware River watershed. The creek's course runs mostly through suburban areas to the north of Philadelphia . However, the course of the creek does run through a few sections of rural and semi-rural terrain, and some forested areas remain. Neshaminy Creek passes through two state parks, Tyler State Park and Neshaminy State Park . Neshaminy Creek has

2754-522: Is similar to brecciated massive mudstone, but its mud fragments are small, rounded clumps. This clumping pattern resembles that of modern salty playas, where dissolved salt gives the lakebed mud a crumbly powdered texture. Traces of mudcracks are still present, but have been heavily deformed by the textural changes. The wettest type of massive mudstone is burrowed massive mudstone, which is thin-bedded mudstone that has been completely homogenized by bioturbation. Saline minerals (typically calcite) are common in

2835-661: Is so heavily bioturbated by burrows that it has a "shredded" appearance, where it is difficult to distinguish the individual layers. The higher-energy shallow water environment means that the sediments which make up thin-bedded mudstone are coarser than those of shale. Most of the shallow mudstone layers are interbedded with siltstone and/or sandstone. In some cases, cross-bedding, ripple marks, or other sedimentary structures can be observed in coarse layers. Though small and rare, stromatolite structures made of micrite are known to occur around some lakeshore sediments. Thin-bedded mudstones with deep mudcracks develop in environments where

2916-425: Is sometimes termed a "young" or "immature" stream, and the later state a "mature" or "old" stream. Meanders are looping changes of direction of a stream caused by the erosion and deposition of bank materials. These are typically serpentine in form. Typically, over time the meanders gradually migrate downstream. If some resistant material slows or stops the downstream movement of a meander, a stream may erode through

2997-456: Is usually called a creek and marked on topographic maps with a solid blue line. There are five generic classifications: "Macroinvertebrate" refers to easily seen invertebrates , larger than 0.5 mm, found in stream and river bottoms. Macroinvertebrates are larval stages of most aquatic insects and their presence is a good indicator that the stream is perennial. Larvae of caddisflies , mayflies , stoneflies , and damselflies require

3078-751: The Brunswick Formation , formed during the Jurassic and Triassic , which consists of mainly mudstone , shale , and siltstone . Mineralogy includes argillite and hornfels . West of Chalfont it passes into an extension of the Lockatong Formation for a short distance, back into the Brunswick, then again to the Lockatong. The Lockatong Formation was deposited during the Triassic and consists of argillite, shale, and occasionally,

3159-691: The Tombigbee River basin. Continuing in this vein, a component of the Mississippi River basin is the Ohio River basin, which in turn includes the Kentucky River basin, and so forth. Stream crossings are where streams are crossed by roads , pipelines , railways , or any other thing which might restrict the flow of the stream in ordinary or flood conditions. Any structure over or in a stream which results in limitations on

3240-480: The velocity of the stream. A perennial stream is one which flows continuously all year. Some perennial streams may only have continuous flow in segments of its stream bed year round during years of normal rainfall. Blue-line streams are perennial streams and are marked on topographic maps with a solid blue line. The word "perennial" from the 1640s, meaning "evergreen," is established in Latin perennis, keeping

3321-524: The Act of Assembly 6th Sept. 1785. The Neshaminy as far as Barnsleys Ford was declared a public highway by Act of 9th March, 1771." The stream has seen a number of major floods, including after seasonal ice. In the Mina flood of 1833, most of the bridges were washed away and was the highest flood known at that time. Compared to the flood of 16–17 July 1865, the 1833 flood was exceeded by 6 feet (1.8 m), rupturing

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3402-704: The Caribbean (for instance, Guinea Gut , Fish Bay Gut , Cob Gut , Battery Gut and other rivers and streams in the United States Virgin Islands , in Jamaica (Sandy Gut, Bens Gut River, White Gut River), and in many streams and creeks of the Dutch Caribbean ). A river is a large natural stream that is much wider and deeper than a creek and not easily fordable, and may be a navigable waterway . The linear channel between

3483-601: The Turk Dam and destroying almost all of the bridges downstream. As the waters reached the Delaware River , the flow was so great as to reach the New Jersey shoreline leaving a large pile of debris and preventing shipping from traversing the river. The Neshaminy has been the subject of many artists over the years. Beginning at the junction of the West Branch and North Branch Neshaminy Creeks, Neshaminy Creek begins in

3564-533: The atmosphere either by evaporation from soil and water bodies, or by plant evapotranspiration. By infiltration some of the water sinks into the earth and becomes groundwater, much of which eventually enters streams. Most precipitated water is partially bottled up by evaporation or freezing in snow fields and glaciers. The majority of the water flows as a runoff from the ground; the proportion of this varies depending on several factors, such as climate, temperature, vegetation, types of rock, and relief. This runoff begins as

3645-525: The base level of erosion throughout its course. If this base level is low, then the stream will rapidly cut through underlying strata and have a steep gradient, and if the base level is relatively high, then the stream will form a flood plain and meander. Typically, streams are said to have a particular elevation profile , beginning with steep gradients, no flood plain, and little shifting of channels, eventually evolving into streams with low gradients, wide flood plains, and extensive meanders. The initial stage

3726-597: The base stage of erosion. The scientists have offered a way based on data to define the origin of the lake. A classified sample was the one measured by the Chinese researchers from the University of Chinese Academy of Sciences. As an essential symbol of the river formation environment, the river source needs an objective and straightforward and effective method of judging . A calculation model of river source catchment area based on critical support flow (CSD) proposed, and

3807-697: The basin with water and sediment. The southwestern river system which flowed into the Newark basin is likely the same as that which formed the Hammer Creek Formation further west. Relative age dating of the Lockatong places it in the Upper Triassic , being deposited between 237 and 207 (±5) million years ago. It rests unconformably below many different formations of the Atlantic Coastal Plain . It interfingers with both

3888-419: The conglomerate layers lie sequences of interbedded mudstone and sandstone, with sandstone beds becoming thicker the higher one goes in a sequence. Unlike the cross-bedded conglomerate, the mudstone and sandstone layers have rare or absent sedimentary structures. Instead, they are heavily bioturbated by burrows and roots. Axial facies are riverbed and overbank deposits from braided rivers flowing down to supply

3969-420: The cyclic nature of the formation is noted with hornfels near diabase and basalt flows. The Lockatong is often described as lake or litoral sediments. The interfingering nature of the sediments with the surrounding Stockton Formation and Passaic Formation suggests that these litoral environments shifted as climate or as the dynamic terrane of the area developed. The deposition of calcitic sediments

4050-462: The deeper they occur within a given layer. They most commonly occur in peloidal massive mudstone, as brine sinks into a saline mudflat and crystallizes. Periodic rains dissolve crystals closer to the surface, explaining why crystals higher in a sequence are smaller and more irregular in shape. While most Lockatong sediments are mudstones associated with lakes or lakebeds, river or stream deposits can also occur. These deposits form in areas equivalent to

4131-448: The deepest parts of the largest lakes. Their layers are very thin and consist of perfectly even, continuous bands of organic material alternating with carbonate (limestone) or clay. Sometimes these shales can be up to 8% organic material by weight. The different layers may be due to seasonal variation in sediment deposition, chemical conditions, and/or algal growth. A complete lack of influence from waves or bioturbating animals indicates that

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4212-485: The distinction of having three tributaries named Mill Creek. The name seems to derive from the Lenape 'Nesha-men-ning', loosely meaning 'the place where we drink twice' or 'two drinking places'. Older names were written as Nishambanach (1671), Nichmink , Nishammis (1679), Nishmines (1680), Neshimineh (1682), Neshamineh (1686), Neshaminia (1688), Neshamenah (1702), and others. This may refer to two springs near

4293-447: The edge of the Newark basin, and typically consist of sandstone and conglomerate. Since the Lockatong Formation is primarily exposed in the center of the Newark basin, basin-margin facies are rare. The overlying Passaic Formation has more extensive exposures near the basin margin, and thus a higher prevalence of sandstone and conglomerate. Thin beds of rippling sandstone are termed wave-dominated sandstone. This type of sandstone formed in

4374-571: The fault, sandstone becomes more common and conglomerate becomes more rare, indicating that the alluvial fans flatten into dry sandy plains. Root casts and burrows are abundant in deposits corresponding to the lower portions of an alluvial fan, where porous sediments and a high water table occur simultaneously. The southwest and northeast corners of the Newark basin have another type of sandstone and conglomerate facies: axial facies. The most visible layers in these areas are graded conglomerate beds with large-scale and easily visible cross-bedding. Between

4455-707: The flow is reduced to a trickle or less. Typically torrents have Apennine rather than Alpine sources, and in the summer they are fed by little precipitation and no melting snow. In this case the maximum discharge will be during the spring and autumn. An intermittent stream can also be called a winterbourne in Britain, a wadi in the Arabic -speaking world or torrente or rambla (this last one from arabic origin) in Spain and Latin America. In Australia, an intermittent stream

4536-447: The form of rain and snow. Most of this precipitated water re-enters the atmosphere by evaporation from soil and water bodies, or by the evapotranspiration of plants. Some of the water proceeds to sink into the earth by infiltration and becomes groundwater, much of which eventually enters streams. Some precipitated water is temporarily locked up in snow fields and glaciers , to be released later by evaporation or melting. The rest of

4617-407: The immediate vicinity of a stream is called a riparian zone . Given the status of the ongoing Holocene extinction , streams play an important corridor role in connecting fragmented habitats and thus in conserving biodiversity . The study of streams and waterways in general is known as surface hydrology and is a core element of environmental geography . A brook is a stream smaller than

4698-532: The lake has significant feeder rivers. The Kagera River, which flows into Lake Victoria near Bukoba's Tanzanian town , is the longest feeder, though sources do not agree on which is the Kagera's longest tributary and therefore the Nile's most remote source itself. To qualify as a stream, a body of water must be either recurring or perennial. Recurring (intermittent) streams have water in the channel for at least part of

4779-486: The lake mud is frequently exposed to dry air. These mudcracks can be simple crevices or more complex multi-branched structures. After a flood, the mudcracks are refilled with mud or other sediments. In some areas tiny circular or elliptical vesicles (air bubbles) are preserved within the refilled mudcracks. Vesicles most commonly form in narrow layers of drying fresh mud deposited on top of older, tougher mud-cracked lake sediments. The mud layers which contain vesicles often have

4860-632: The lakes were very deep and anoxic at their lowest extents. Fossils such as well-preserved fish skeletons are common in the absence of decomposing organisms. The minimum depth necessary to maintain this environment has been estimated to range from 60 meters to up to 80 or 100 meters. Red to grey thin-bedded mudstones are lake or lakeshore sediments intermediate in layer width between shale and massive mudstone. Graded and "pinch-and-swell" layers are common in these facies. This indicates that these shallower sediments experienced disturbances like floods or increased wave action during storms. Other thin-bedded mudstone

4941-683: The mainly easterly-draining Atlantic Ocean and Arctic Ocean basins from the largely westerly-flowing Pacific Ocean basin. The Atlantic Ocean basin, however, may be further subdivided into the Atlantic Ocean and Gulf of Mexico drainages. (This delineation is termed the Eastern Continental Divide .) Similarly, the Gulf of Mexico basin may be divided into the Mississippi River basin and several smaller basins, such as

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5022-412: The meaning as "everlasting all year round," per "over" plus annus "year." This has been proved since the 1670s by the "living years" in the sense of botany. The metaphorical sense of "enduring, eternal" originates from 1750. They are related to "perennial." See biennial for shifts in vowels. Perennial streams have one or more of these characteristics: Absence of such characteristics supports classifying

5103-643: The movement of fish or other ecological elements may be an issue. Lockatong Formation The Triassic Lockatong Formation is a mapped bedrock unit in Pennsylvania , New Jersey , and New York . It is named after the Lockatong Creek in Hunterdon County, New Jersey . The Lockatong is defined as a light to dark gray, greenish-gray, and black very fine grained sandstone , silty argillite , and laminated mudstone . In New Jersey,

5184-529: The mudstones of the Lockatong Formation. Calcite crystals may be present in the form of hexagonal pseudomorphs . The original hexagonal crystal (now replaced by calcite) was probably pirssonite or a similar mineral, which settled on the lakebed after crystallizing near the water surface. In laminated mudstone, some laminae may consist entirely of sheets of hexagonal calcite crystals. They act similar to sand grains and can occur in graded, "pinch-and-swell", and continuous laminae of lake mudstone. Crystal clasts are

5265-453: The neck between two legs of a meander to become temporarily straighter, leaving behind an arc-shaped body of water termed an oxbow lake or bayou . A flood may also cause a meander to be cut through in this way. The stream load is defined as the solid matter carried by a stream. Streams can carry sediment, or alluvium. The amount of load it can carry (capacity) as well as the largest object it can carry (competence) are both dependent on

5346-596: The origin of the Nile River is the confluence of the White Nile and the Blue Nile, but the source of the whole river system is in its upper reaches. If there is no specific designation, "length of the Nile" refers to the "river length of the Nile system", rather than to the length of the Nile river from the point where it is formed by a confluence of tributaries. The Nile's source is often cited as Lake Victoria, but

5427-430: The other hand, has a relatively constant input and is controlled more by long-term patterns of precipitation. The stream encompasses surface, subsurface and groundwater fluxes that respond to geological, geomorphological, hydrological and biotic controls. Streams are important as conduits in the water cycle , instruments in groundwater recharge , and corridors for fish and wildlife migration. The biological habitat in

5508-415: The parallel ridges or bars on a shoreline beach or river floodplain, or between a bar and the shore. Also called a swale . A tributary is a contributory stream to a larger stream, or a stream which does not reach a static body of water such as a lake , bay or ocean but joins another river (a parent river). Sometimes also called a branch or fork. A distributary , or a distributary channel ,

5589-469: The relationship between CSA and CSD with a minimum catchment area established. Using the model for comparison in two basins in Tibet (Helongqu and Niyang River White Water), the results show that the critical support flow (Qc) of the housing dragon song is 0.0028 m /s. At the same time, the white water curvature is 0.0085 m /s. Besides, the critical support flow can vary with hydrologic climate conditions, and

5670-712: The sand is exposed to the air. Some rivers flowing into the basin create deltas along the edges of lakes. Lockatong deltas produced sandstone beds with climbing ripple cross-bedding, a specialized sedimentary structure indicative of decelerating water. Some deltaic sandstone bedding is similar to the foreset beds of wave-dominated sandstone. However, the layers are more bowl-shaped and clinoform (i.e. stacked at much steeper angles). Upward-coarsening trends are still abundant, and root casts are sometimes found as well. Clinoform deltaic sandstone formed in Gilbert deltas , which involve coarse riverbed sediments abruptly being deposited onto

5751-415: The sandy shallows of lakes with low-angled lakebeds. Their characteristic wavy layering represents ripple marks formed during storms and other disruptive events. Slightly thicker sandstone foreset beds (preserved sandbars) are often associated with wave-dominated sandstone. Sandstone beds overlying mudstone become coarser the further up one goes in the sequence. Mudcrack-like structures can also develop when

5832-469: The sheet deltas and the ephemeral lakes supplied by them would have dried up shortly afterwards. Deformation is common within the sheet delta sandstone layers due to repeated sheet floods through time. Close to the Ramapo Fault (which forms the northern border of the Newark basin), conglomerate becomes the dominant form of sediment. Border fault conglomerate is locally common but can only be found in

5913-483: The shoreline, where they decomposed or were scavenged by phytosaurs , leading to the formation's distinctive deposits of numerous disarticulated fish parts. Invertebrate burrows are the most common fossils in the Lockatong Formation. Eupelor E. durus Phoenixville? Shoulder girdle elements An dubious amphibian, potentially a metoposaurid Gwyneddosaurus G. erici Gwynedd Partial skeleton (Gastric ejection) A dubious reptile, likely

5994-425: The side of the stream or within the floodplain will be a good indicator of persistent water regime. A perennial stream can be identified 48 hours after a storm. Direct storm runoff usually has ceased at this point. If a stream is still flowing and contributing inflow is not observed above the channel, the observed water is likely baseflow. Another perennial stream indication is an abundance of red rust material in

6075-439: The upper margin of the lenses. These facies are termed matrix-supported conglomerate, corresponding to debris flows on an alluvial fan . Some conglomerate involves bands of smaller pebbles interbedded with laminated sandstone in lenses with flat upper margins and concave lower margins. This type of conglomerate is known as clast-supported conglomerate, which was deposited in ephemeral stream channels on an alluvial fan. Away from

6156-655: The vital support flow Qc in wet areas (white water) is larger than in semi-arid regions (heap slot). The proposed critical support flow (CSD) concept and model method can be used to determine the hydrographic indicators of river sources in complex geographical areas, and it can also reflect the impact of hydrologic climate change on river recharge in different regions. The source of a river or stream (its point of origin) can consist of lakes, swamps, springs, or glaciers. A typical river has several tributaries; each of these may be made up of several other smaller tributaries, so that together this stream and all its tributaries are called

6237-512: The water flows off the land as runoff, the proportion of which varies according to many factors, such as wind, humidity, vegetation, rock types, and relief. This runoff starts as a thin film called sheet wash, combined with a network of tiny rills, together constituting sheet runoff; when this water is concentrated in a channel, a stream has its birth. Some creeks may start from ponds or lakes. The streams typically derive most of their water from rain and snow precipitation. Most of this water re-enters

6318-521: The year and is marked on topographic maps with a line of blue dashes and dots. A wash , desert wash, or arroyo is normally a dry streambed in the deserts of the American Southwest , which flows after sufficient rainfall. In Italy, an intermittent stream is termed a torrent ( Italian : torrente ). In full flood the stream may or may not be "torrential" in the dramatic sense of the word, but there will be one or more seasons in which

6399-402: The year. A stream of the first order is a stream which does not have any other recurring or perennial stream feeding into it. When two first-order streams come together, they form a second-order stream. When two second-order streams come together, they form a third-order stream. Streams of lower order joining a higher order stream do not change the order of the higher stream. The gradient of

6480-523: Was the first stream in Bucks County to have been crossed by ferries and bridges . The Gordon Gazetteer of 1832 called it the Neshaminy River and stated that "over it, there are many fine wooden and stone bridges. The bridge nearest its mouth on the road to New York is a draw bridge-in private property, erected by the Messrs. Bassonet and Johnson, whose heirs and assigns levy tolls by virtue of

6561-732: Was the site of significant flooding again from June 25 through July 5, 2006 during the Mid-Atlantic United States flood of 2006 . In late August through early September 2011, Hurricane Irene , and Tropical Storm Lee (2011) rose the Neshaminy Creek to levels which had not seen before in 100 years. Repairs cost around $ 1 million total. Stream The flow of a stream is controlled by three inputs – surface runoff (from precipitation or meltwater ), daylighted subterranean water , and surfaced groundwater ( spring water ). The surface and subterranean water are highly variable between periods of rainfall. Groundwater, on

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