Verneshot
Encyclopedia
A verneshotA verneshot (named after French
France
The French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...

 author
Author
An author is broadly defined as "the person who originates or gives existence to anything" and that authorship determines responsibility for what is created. Narrowly defined, an author is the originator of any written work.-Legal significance:...

 Jules Verne
Jules Verne
Jules Gabriel Verne was a French author who pioneered the science fiction genre. He is best known for his novels Twenty Thousand Leagues Under the Sea , A Journey to the Center of the Earth , and Around the World in Eighty Days...

) is a hypothetical volcanic eruption event caused by the buildup of gas deep underneath a craton
Craton
A craton is an old and stable part of the continental lithosphere. Having often survived cycles of merging and rifting of continents, cratons are generally found in the interiors of tectonic plates. They are characteristically composed of ancient crystalline basement rock, which may be covered by...

. Such an event may be forceful enough to launch an extreme amount of material from the crust
Crust (geology)
In geology, the crust is the outermost solid shell of a rocky planet or natural satellite, which is chemically distinct from the underlying mantle...

 and mantle
Mantle (geology)
The mantle is a part of a terrestrial planet or other rocky body large enough to have differentiation by density. The interior of the Earth, similar to the other terrestrial planets, is chemically divided into layers. The mantle is a highly viscous layer between the crust and the outer core....

 into a sub-orbital trajectory
Trajectory
A trajectory is the path that a moving object follows through space as a function of time. The object might be a projectile or a satellite, for example. It thus includes the meaning of orbit—the path of a planet, an asteroid or a comet as it travels around a central mass...

.

Connection with mass extinctions

Verneshots have been proposed as a causal mechanism explaining the statistically unlikely contemporaneous occurrence of continental flood basalt
Flood basalt
A flood basalt or trap basalt is the result of a giant volcanic eruption or series of eruptions that coats large stretches of land or the ocean floor with basalt lava. Flood basalts have occurred on continental scales in prehistory, creating great plateaus and mountain ranges...

s, mass extinctions, and "impact signals" (such as planar deformation features
Planar deformation features
Planar deformation features, or PDFs, are optically recognizable microscopic features in grains of silicate minerals , consisting of very narrow planes of glassy material arranged in parallel sets that have distinct orientations with respect to the grain's crystal structure.PDFs are only produced...

, shocked quartz
Shocked quartz
Shocked quartz is a form of quartz that has a microscopic structure that is different from normal quartz. Under intense pressure , the crystalline structure of quartz will be deformed along planes inside the crystal...

, and iridium anomalies
Iridium anomaly
The term iridium anomaly commonly refers to an unusual abundance of the chemical element iridium in a layer of rock strata, often taken as evidence of an extraterrestrial impact event because of the case of such an anomaly at the Cretaceous–Tertiary boundary...

) traditionally considered definitive evidence of hypervelocity impact event
Impact event
An impact event is the collision of a large meteorite, asteroid, comet, or other celestial object with the Earth or another planet. Throughout recorded history, hundreds of minor impact events have been reported, with some occurrences causing deaths, injuries, property damage or other significant...

s.

The verneshot theory suggests that mantle plume
Mantle plume
A mantle plume is a hypothetical thermal diapir of abnormally hot rock that nucleates at the core-mantle boundary and rises through the Earth's mantle. Such plumes were invoked in 1971 to explain volcanic regions that were not thought to be explicable by the then-new theory of plate tectonics. Some...

s may cause heating and the buildup of carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...

 gas underneath continental lithosphere
Lithosphere
The lithosphere is the rigid outermost shell of a rocky planet. On Earth, it comprises the crust and the portion of the upper mantle that behaves elastically on time scales of thousands of years or greater.- Earth's lithosphere :...

. If continental rift
Rift
In geology, a rift or chasm is a place where the Earth's crust and lithosphere are being pulled apart and is an example of extensional tectonics....

ing occurs above this location, an explosive release of the built up gas may occur, potentially sending out a column of crust and mantle into a globally dispersive, super-stratospheric
Stratosphere
The stratosphere is the second major layer of Earth's atmosphere, just above the troposphere, and below the mesosphere. It is stratified in temperature, with warmer layers higher up and cooler layers farther down. This is in contrast to the troposphere near the Earth's surface, which is cooler...

 trajectory. It is unclear whether such a column could stay coherent through this process, or whether the force of this process would result in it shattering into much smaller pieces before impacting. The pipe through which the magma and gas had travelled would collapse during this process, sending a shockwave at hypersonic velocity that would deform the surrounding craton
Craton
A craton is an old and stable part of the continental lithosphere. Having often survived cycles of merging and rifting of continents, cratons are generally found in the interiors of tectonic plates. They are characteristically composed of ancient crystalline basement rock, which may be covered by...

.

A verneshot event is likely to be related to nearby continental flood basalt events, which may occur before, during or after the verneshot event. This may help in searching for evidence for the results of verneshot events; however, it is also quite probable that most of such evidence will be buried underneath the basalt flows, making investigation difficult. J. Phipps Morgan et al. have suggested that subcircular Bouguer gravity anomalies
Bouguer anomaly
In geodesy and geophysics, the Bouguer anomaly is a gravity anomaly, corrected for the height at which it is measured and the attraction of terrain. The height correction alone gives a free-air anomaly.-Bouguer reduction:...

 recognized beneath the Deccan Traps
Deccan Traps
The Deccan Traps are a large igneous province located on the Deccan Plateau of west-central India and one of the largest volcanic features on Earth. They consist of multiple layers of solidified flood basalt that together are more than thick and cover an area of and a volume of...

 may indicate the presence of verneshot pipes related to the Cretaceous–Tertiary extinction event.

If the Deccan Traps were the location of a verneshot event at the K–T boundary
K–T boundary
The K–T boundary is a geological signature, usually a thin band, dated to 65.5 ± 0.3 Ma ago. K is the traditional abbreviation for the Cretaceous period, and T is the abbreviation for the Tertiary period...

, the strong iridium spike at the K–T boundary could be explained by the iridium-rich nature in volatiles of the Reunion mantle plume, which is currently beneath Piton de la Fournaise
Piton de la Fournaise
Piton de la Fournaise : "Peak of the Furnace" is a shield volcano on the eastern side of Réunion island in the Indian Ocean. It is currently one of the most active volcanoes in the world, along with Kīlauea in the Hawaiian Islands , Stromboli, Etna and Mount Erebus in Antarctica...

, but during the end Cretaceous was located beneath India in the area of the Deccan Traps; the verneshot event could potentially distribute the iridium globally.

Smaller scale Verneshots

Less dramatic rock eruptions were documented in 2003 after a 1999 Earthquake in central Taiwan
Taiwan
Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...

.

Smaller scale verneshot events were proposed by Phipps Morgan et al. to be a possible causual mechanism for the intrusion of kimberlite
Kimberlite
Kimberlite is a type of potassic volcanic rock best known for sometimes containing diamonds. It is named after the town of Kimberley in South Africa, where the discovery of an diamond in 1871 spawned a diamond rush, eventually creating the Big Hole....

 pipes, which propagate along lines of crustal weakness produced by an earlier larger verneshot event.

The site of the 1908 Tunguska event
Tunguska event
The Tunguska event, or Tunguska blast or Tunguska explosion, was an enormously powerful explosion that occurred near the Podkamennaya Tunguska River in what is now Krasnoyarsk Krai, Russia, at about 7:14 a.m...

 is proposed as a possible location of a recent micro-verneshot or kimberlite event. The site of ground zero in Tunguska is located within the Siberian traps, a large igneous province
Large igneous province
A Large Igneous Province is an extremely large accumulation of igneous rocks—intrusive, extrusive, or both—in the earth's crust...

, formed at the Permo-Triassic boundary and, interestingly, recent work has indicated a circular depression underlying the traps, a direct prediction of the verneshot model. In the verneshot model, the cratonic crust beneath this region would remain as a point of weakness, allowing the intrusion of a kimberlite pipe or, alternatively, a micro-verneshot, degassing from intrusion, resulted in an outpouring of volcanic gas which was then ignited. However the theory is controversial and is simply stated as a possible example.

The micro-verneshot model does not require the ejection of crustal material—only intrusion at depth.

History

In 1865 Jules Verne
Jules Verne
Jules Gabriel Verne was a French author who pioneered the science fiction genre. He is best known for his novels Twenty Thousand Leagues Under the Sea , A Journey to the Center of the Earth , and Around the World in Eighty Days...

's novel From the Earth to the Moon
From the Earth to the Moon
From the Earth to the Moon is a humorous science fantasy novel by Jules Verne and is one of the earliest entries in that genre. It tells the story of the president of a post-American Civil War gun club in Baltimore, his rival, a Philadelphia maker of armor, and a Frenchman, who build an enormous...

introduced the concept of a ballistic
Ballistics
Ballistics is the science of mechanics that deals with the flight, behavior, and effects of projectiles, especially bullets, gravity bombs, rockets, or the like; the science or art of designing and accelerating projectiles so as to achieve a desired performance.A ballistic body is a body which is...

 projectile escaping the Earth's gravity, from which Phipps Morgan et al. derived the name "Verneshot" in their paper theorizing cratonic gas ejection's connection to extinction events. This was in the projectile-naming tradition of John Hunter
John Hunter (scientist)
John Hunter is a projectile researcher, who developed the 1994 "supergun" Super High Altitude Research Project at the Lawrence Livermore National Laboratory...

, whose 47 m expanding hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

 gun, SHARP
Super High Altitude Research Project
The Super High Altitude Research Project was a U.S. government project conducting research into the firing of high-velocity projectiles high into the atmosphere using a two stage light gas gun, with the ultimate goal of propelling satellites into Earth orbit...

, is only a precursor to the "Jules Verne Launcher" with a 3,500 m barrel length, which was designed in the early 1990s for first-stage satellite
Satellite
In the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavour. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon....

launch.
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