In sedimentary geology and fluvial geomorphology, avulsion is the rapid abandonment of a river channel and the formation of a new river channel. Avulsions occur as a result of channel slopes that are much less steep than the slope that the river could travel if it took a new course.
Deltaic and net-depositional settings
Avulsions are common in deltaic settings, where sedimentdeposits as the river enters the ocean and channel gradients are typically very small. This process of avulsion in deltaic settings is also known as delta switching.
Deposition from the river results in the formation of an individual deltaic lobe that pushes out into the sea. An example of a deltaic lobe is the bird's-foot delta of the Mississippi River, pictured at right with its sediment plumes. As the deltaic lobe advances, the slope of the river channel becomes lower because the river channel is longer but has the same change in elevation (see slope or gradient). As the slope of the river channel decreases, it becomes unstable for two reasons. First, water under the force of gravity will tend to flow in the most direct course downslope. If the river could breach its natural levees (i.e., during a flood), it would spill out onto a new course with a shorter route to the ocean, thereby obtaining a more stable steeper slope. Second, as its slope is reduced, the amount of shear stress on the bed will decrease, resulting in deposition of more sediment within the channel and thus raising of the channel bed relative to the floodplain. This will make it easier for the river to breach its levees and cut a new channel that enters the ocean at a steeper slope.
In real property law, avulsion refers to a sudden loss or addition to land, which results from the action of water. It differs from accretion, which describes a gradual loss or addition to land resulting from the action of water.
Avulsion and riparian owners
The distinction between avulsion and accretion becomes important where a river forms the boundary between two riparian owners. In many states (though not all), if the river changes channels by avulsion, the boundary does not change; it remains in the middle of the old channel. (This is why if you look at maps of the lower Mississippi river, you will find that some land on the east side of the river is part of Arkansas, and some land on the west side of the river is part of Tennessee. The river changed course quickly, so the state boundary did not change. However, as a river gradually changes through accretion, the boundary changes with it.
To prove that a change was avulsion and not accretion, it is sufficient for the owner of land which was washed away to point out approximately as much land added to the opposite bank as washed away from his bank.
In medicine, an avulsion is an injury in which a body structure is forcibly detached from its normal point of insertion by either trauma or surgery (from the Latin avellere, meaning "to tear off"). The term most commonly refers to a surface trauma where all layers of the skin have been torn away, exposing the underlying structures (i.e., subcutaneous tissue, muscle, tendons, or bone). This is similar to an abrasion but more severe, as body parts such as an eyelid or an ear can be partially or fully detached from the body.
Types of avulsions
Skin
Ear
Eyelid
Nail
Nerve (brachial plexus)
Tooth
Periosteal
Surgical
Skin avulsions
The most common avulsion injury, skin avulsions usually occur during motor vehicle collisions. The severity of avulsion ranges from skin flaps (minor) to degloving (moderate) and amputation of a finger or limb (severe). Suprafascial avulsions are those in which the depth of the removed skin reaches the subcutaneous tissue layer, while subfascial avulsions extend deeper than the subcutaneous layer. Small suprafascial avulsions can be repaired by suturing, but most avulsions require skin grafts or reconstructive surgery.
Malcolm Reynolds, played by Nathan Fillion, is owner and captain of the Firefly-class spaceship Serenity, and was a volunteer in the war between the Alliance and the Independents (aka "Browncoats"). He got the name for his spaceship from a famous battle he fought and commanded in, the Battle of Serenity Valley. When asked why he named his ship after a lost battle, Zoe comments "Once you're in Serenity, you never leave. You just learn how to live there." He is fiercely loyal to those he calls his crew.
Malcolm's main mission is to keep his crew alive and to keep his ship flying. As Firefly writer Tim Minear stated in an interview: "It's just about getting by. That's always been the mission statement of what the show is— getting by." In "Serenity", Mal says of himself: "[If the] Wind blows northerly, I go North."
Screens from Serenity suggest that Mal was born on September 20, 2468— which would make him 49 at the time of the series Firefly— though, as the average human lifespan is 120, this would make him the equivalent of a man in his early 30s today. Mal was raised by his mother and "about 40 hands" on a ranch on the planet Shadow. Though Mal usually seems more practical than intellectual, he occasionally surprises his friends by displaying familiarity with disparate literature varying from the works of Xiang Yu to poems by Samuel Taylor Coleridge, though he has no idea "who" Mona Lisa is.
River is a 2011 Japanese drama film based on the 2008 Akihabara massacre incident. The film is written and directed by Ryūichi Hiroki. The film stars actress Misako Renbutsu, who will play the role of a person who lost her love interest in the attacks.
River debuted at the 12th Tokyo Filmex as one of its special presentations. It will subsequently be released in Japanese cinemas on 10 March 2012.
Plot
Hikari's boyfriend is one of those killed in the Akihabara massacre incident. Suffering from the shock of her loss and unable to accept this reality, she cuts herself off from the outside world. She eventually manages to muster enough courage to visit Akihabara, the scene of the incident. There, she encounters many people who are still coming to terms with the aftermath of the incident and are still suffering from the aftereffects.
Cast
Misako Renbutsu as Hikari, a woman whose boyfriend was a victim in the attacks.
The following is a glossary of poker terms used in the card game of poker. It supplements the glossary of card game terms. Besides the terms listed here, there are thousands of common and uncommon poker slang terms. This is not intended to be a formal dictionary; precise usage details and multiple closely related senses are omitted here in favor of concise treatment of the basics.
Researchers have uncovered key insights into the dangerous phenomenon of 'river avulsion,' offering a way to predict when and where rivers may suddenly and dramatically change course ... .
Avulsions occur when a river's water rises above the surrounding landscape, often due to the buildup of sediment in the riverbed ... For example, the 2008 avulsion of the Kosi River in Northern India ...
four lines restricting land below the highwater mark, artificial or accreted lands, land withing the boundaries by an avulsive movement, and any rights of access for recreational purposes which may exist over the land … of the TruckeeRiver.
“It’s normal for rivers to move completely from one place to another in the landscape, and we refer to that as a process called avulsion,” said Chamberlain, an assistant professor in the environmental ...
Scientists have documented many river-course changes, called avulsions, including some in response to earthquakes ... ‘Cascading hazards of a major Bengal basin earthquake and abrupt avulsion of the GangesRiver.’ Nature Communications 15, 4975 (2024).
The discovery is something of a breakthrough, as while we’ve long known about rivers changing course – something known to science as avulsions – before now it hadn’t been confirmed that earthquakes could be the driving force.
Scientists have documented many river-course changes, called avulsions, including some in response to earthquakes ... Cascading hazards of a major Bengal basin earthquake and abrupt avulsion of the GangesRiver, Nature Communications (2024).
And while he’s there, he wants to visit Carter Lake, the only Iowa city that’s located west of the MissouriRiver... The that if a river shifted suddenly, through what’s called “avulsion,” there is no effect on the boundary.
The heavily avulsing river bed also spurred council to revise and relaunch a 10-year strategy to manage the river, which was released to the community in October ... in the Waiho RiverStrategy.
The study specifically looks at river sinuosity, or how much rivers curve ... Chenliang Wu et al, Lowland river sinuosity on Earth and Mars set by the pace of meandering and avulsion, Nature Geoscience (2023).
Avulsions on China’sYellowRiver killed over 6 million people in the late 19th and early 20th centuries... In a 2022 published study, I worked with colleagues to map the global distribution of avulsions on river fans and deltas.
In some cases, the sudden river shifts—also known as avulsion—may even cause the river to establish a new channel within the landscape ...Erin McEwan et al, Coseismic river avulsion on surface rupturing faults.
Within hours, the river flooded outside its channel and changed course ... In some cases, the sudden river shifts - also known as avulsion - may even cause the river to establish a new channel within the landscape.
“Avulsions on ... Avulsions differ from the river-reversal of the Mississippi in that rather than keeping a river on-course but flowing backwards, they see a river suddenly up and carve out a new path.
Hastings Tribune
15 Jul 2023
Hastings Tribune
15 Jul 2023