title: Christy Mathewson

text: During his 17-year career, Mathewson won 373 games and lost 188 for a .665 winning percentage. His career earned run average of 2.13 and 79 career shutouts are among the best all time for pitchers, and his 373 wins are still number one in the National League, tied with Grover Cleveland Alexander. He employed a good fastball, outstanding control, and, especially a new pitch he termed the "fadeaway" (later known in baseball as the "screwball"), which he learned from teammate Dave Williams in 1898.


title: Christy Mathewson

text: This reference is challenged by Ken Burns documentary "Baseball" in which it is stated that Mathewson learned his "fadeaway" from Andrew "Rube" Foster when New York Giants manager John McGraw quietly hired Rube to show the Giants bullpen what he knew. Many baseball historians consider this story apocryphal.


title: Christy Mathewson

text: Mathewson recorded 2,507 career strikeouts against only 848 walks. He is famous for his 25 pitching duels with Mordecai "Three Finger" Brown, who won 13 of the duels against Mathewson's 11, with one no-decision.


title: Christy Mathewson

text: Mathewson was a very good-hitting pitcher in his major league career, posting a .215 batting average (362-for-1687) with


title: Christy Mathewson

text: 151 runs, seven home runs, and 167 runs batted in. In 10 of his 17 years in the majors, he was in double figures in runs batted in, with a season-high of 20 in 1903. He batted .281 (9-for-32) in 11 World Series games.


title: Christy Mathewson

text: By 1903, Mathewson's stature was such that when he briefly signed a contract with the St. Louis Browns of the American League, he was thought to be the spark the Browns needed to win the pennant. The Browns had finished a strong second in 1902, five games behind the Philadelphia Athletics. They offered him four times what he was making with the Giants. However, as part of the settlement that ended the two-year war between the American and National Leagues, Mathewson and Browns owner Robert Lee Hedges tore up the contract. Hedges later said that ensuring the return of peace to the game was more important, even if it meant effectively giving up a pennant.


title: Christy Mathewson

text: From 1900 to 1904, Mathewson established himself as a premier pitcher. Posting low earned run averages and winning nearly 100 games, Mathewson helped lead the Giants to their first National League title in 1903, and a berth in first World Series. Though no World Series was held in 1904, the Giants captured the pennant, prompting McGraw to proclaim them as the best team in the world.


title: Christy Mathewson

text: Mathewson strove even harder in 1905. After switching to catcher, Roger Bresnahan had begun collaborating with Mathewson, whose advanced memory of hitter weaknesses paved the way for a historic season. Pinpoint control guided Mathewson's pitches to Bresnahan's glove. In 338 innings, Mathewson walked only 64 batters. He shut out opposing teams eight times, pitching entire games in brief 90-minute sessions. Besides winning 31 games, Mathewson recorded an earned run average of 1.28 and 206 strikeouts. He led the National League in all three categories, earning him the Triple Crown.


title: Christy Mathewson

text: Mathewson's Giants won the 1905 World Series over the Philadelphia Athletics. Mathewson was the starting pitcher in game one, and pitched a four-hit shutout for the victory. Three days later, with the series tied 1–1, he pitched another four-hit shutout. Then, two days later in game five, he threw a six-hit shutout to clinch the series for the Giants. In a span of only six days, Mathewson had pitched three complete games without allowing a run, while giving up only 14 hits.


title: Christy Mathewson

text: The next year, Mathewson lost much of his edge, owing to an early-season diagnosis of diphtheria. McGraw pulled over 260 innings from him, but these were plagued with struggle. Though he maintained a 22–12 record, his 2.97 earned run average was well above the league average of 2.62. His 1.271 walks plus hits per innings pitched, quite uncharacteristic of him, was due to an increased number of hits and walks.


title: Christy Mathewson

text: By 1908, Mathewson was back on top as the league's elite pitcher. Winning the most games of his career, 37, coupled with a 1.43 earned run average and 259 strikeouts, he claimed a second triple crown. He also led the league in starts, innings pitched, complete games, and shutouts, and held hitters to an exceptionally low 0.827 walks plus hits per innings pitched. He even led the league in saves, racking up 5 of them in 12 relief appearances. Unfortunately, the Giants were unable to take home the pennant due to what was ultimately known as Merkle's Boner, an incident that cost the Giants a crucial game against the Chicago Cubs, who eventually defeated the Giants in the standings by one game.


title: Christy Mathewson

text: Mathewson returned for an outstanding 1909 season; though not as dominant as the previous year, he posted a better earned run average (1.14), and a record of 25-6. He repeated a strong performance in 1910 and then again in 1911, when the Giants captured their first pennant since 1905. The Giants ultimately lost the 1911 World Series to the Philadelphia Athletics, the same team they had defeated for the 1905 championship. Mathewson and Rube Marquard allowed two game-winning home runs to Hall of Famer Frank Baker, earning him the nickname, "Home Run". Mathewson, the team's "star pitcher", signed a three-year contract with the Giants in late 1910, for the upcoming 1911, 1912 and 1913 seasons, the first time he had signed a contract over a year in length.


title: Christy Mathewson

text: In 1912, Mathewson gave another stellar performance. Capturing the pennant, the Giants were fueled by the stolen-base game and a superior pitching staff capped by Rube Marquard, the "11,000-dollar lemon" who turned around to win 26 games, 19 of them consecutively. In the 1912 World Series, the Giants faced the Boston Red Sox, the 1904 American League pennant winners who would have faced the Giants in the World Series that year had one been played. Though Mathewson threw three complete games and maintained an earned run average below 1.00, numerous errors by the Giants, including a lazy popup dropped by Fred Snodgrass in the eighth game (Game 2 was a tie), cost them the championship. The Giants also lost the 1913 World Series, a 101-win season cemented by Mathewson's final brilliant season on the mound: a league-leading 2.06 earned run average in over 300 innings pitched complemented by 0.6 bases on balls per nine innings pitched.


title: Christy Mathewson

text: For the remainder of his career with the Giants, Mathewson began to struggle. Soon, the former champions fell into decline. In 1915, Mathewson's penultimate season in New York, the Giants were the worst team in the National League standings. Mathewson, who had expressed interest in serving as a manager, wound up with a three-year deal to manage the Cincinnati Reds effective July 21, 1916.


title: Christy Mathewson

text: On July 20, 1916, Mathewson's career came full circle when he was traded to the Cincinnati Reds along with Edd Roush. He was immediately named as the Reds' player-manager. However, he appeared in only one game as a pitcher for the Reds, on September 4, 1916. He faced Brown in the second half of a doubleheader, which was billed as the final meeting between the two old baseball warriors. The high-scoring game was a win for Mathewson's Reds over Brown's Cubs, 10–8.


title: Christy Mathewson

text: Mathewson retired as a player after the season and managed the Reds for the entire 1917 season and the first 118 games of 1918, compiling a total record of 164-176 as a manager.


title: Christy Mathewson

text: Mathewson married Jane Stoughton (1880–1967) in 1903. Their only son, Christopher Jr., was born shortly after. Christy Mathewson Jr. served in World War II, and died in an explosion at his home in Texas on August 16, 1950. During Mathewson's playing years, the family lived in a duplex in upper Manhattan alongside Mathewson's manager John McGraw and his wife Blanche. Mathewson and McGraw remained friends for the rest of their lives. In the 1909 offseason, Christy Mathewson's younger brother Nicholas Mathewson committed suicide in a neighbor's barn. Another brother, Henry Mathewson, pitched briefly for the Giants before dying of tuberculosis in 1917.


title: Christy Mathewson

text: Mathewson was highly regarded in the baseball world during his lifetime. As he was a clean-cut, intellectual collegiate, his rise to fame brought a better name to the typical ballplayer, who usually spent his time gambling, boozing, or womanizing. As noted in "The National League Story" (1961) by Lee Allen, Mathewson was a devout Christian and never pitched on Sunday, a promise he made to his mother that brought him popularity among the more religious New York fans and earned him the nickname "The Christian Gentleman". However, the impact of this practice on the Giants was minimized, since, in the eight-team National League, only the Chicago Cubs (Illinois), Cincinnati Reds (Ohio), and St. Louis Cardinals (Missouri) played home games in states that allowed professional sports on Sunday.


title: Christy Mathewson

text: In his free time, Mathewson enjoyed nature walks, reading, golf, and checkers, of which he was a renowned champion player. The combination of athletic skill and intellectual hobbies made him a favorite for many fans, even those opposed to the Giants. Sportswriters praised him, and in his prime every game he started began with deafening cheers. Sometimes, the distraction prompted him to walk out 10 minutes after his fielders took the field. Mathewson soon became the unspoken captain of the Giants.


title: Christy Mathewson

text: He was the only player to whom John McGraw ever gave full discretion. McGraw told many younger players to watch and listen to his wisdom.


title: Christy Mathewson

text: Mathewson garnered respect throughout the baseball world as a pitcher of great sportsmanship. He was often asked to write columns concerning upcoming games. In 1912, with the editing and ghostwriting aid of sportswriter John Wheeler, Mathewson published his classic memoir "Pitching in a Pinch," or Pitching from the Inside, which was admired by poet Marianne Moore and is still in print. Years later, Mathewson co-wrote a mildly successful play called "The Girl and The Pennant", which was inspired by Helene Hathaway Britton's ownership of the St. Louis Cardinals. Mathewson went on to pursue more literary endeavors ending in 1917 with a children's book called "Second Base Sloan".


title: Christy Mathewson

text: One of the journalists to unmask the 1919 Black Sox, Hugh Fullerton, consulted Mathewson for information about baseball gambling. Fullerton trusted Mathewson for his writing intellect, as well as his unbiased standpoint. As a player and manager, Mathewson also had several seasons of experience playing alongside Hal Chase, a veteran major league player widely rumored to have been involved in several gambling incidents and attempts to fix games.


title: Christy Mathewson

text: Representing the only former ballplayer among the group of investigating journalists, Mathewson played a small role in Fullerton's exposure of the 1919 World Series scandal.


title: Christy Mathewson

text: Late in the 1918 season, Mathewson enlisted in the United States Army for World War I. His wife Jane was very much opposed to the decision, but Mathewson insisted on going. He served overseas as a captain in the newly formed Chemical Service along with Ty Cobb. When he arrived in France, he was accidentally gassed during a chemical training exercise and subsequently developed tuberculosis, which more easily infects lungs that have been damaged by chemical gases. Mathewson served with the American Expeditionary Forces until February 1919 and was discharged later that month.


title: Christy Mathewson

text: Although he returned to serve as a coach for the Giants from 1919 to 1921, he spent a good portion of that time in Saranac Lake fighting the tuberculosis, initially at the Trudeau Sanitorium, and later in a house that he had built. In 1923, Mathewson returned to professional baseball when Giants attorney Emil Fuchs and he put together a syndicate that bought the Boston Braves. Although initial plans called for Mathewson to be principal owner and team president, his health had deteriorated so much that he could perform only nominal duties. He turned over the presidency to Fuchs after the season.


title: Christy Mathewson

text: After contracting tuberculosis, Mathewson moved to the frigid climate of Saranac Lake, New York, in the Adirondack Mountains, where he sought treatment from Edward Livingston Trudeau at his renowned Adirondack Cottage Sanitarium. He died in Saranac Lake of tuberculosis on October 7, 1925. Mathewson is buried at Lewisburg Cemetery in Lewisburg, Pennsylvania, adjacent to Bucknell University. Members of the Pittsburgh Pirates and the Washington Senators wore black armbands during the 1925 World Series. Mathewson had died on the day the series began, October 7. According to "Baseball", some of Mathewson's last words were to his wife: "Now Jane, I want you to go outside and have yourself a good cry. Don't make it a long one; this can't be helped."


title: Alive! (Kiss album)

text: Alive! is the fourth album overall, and the first live album, by American hard rock band Kiss. It is considered to be their breakthrough and a landmark for live albums. Released on September 10, 1975, the double-album contains live versions of selected tracks from their first three studio albums, "Kiss", "Hotter Than Hell" and "Dressed to Kill". It was recorded at concerts in Detroit, Michigan; Cleveland, Ohio; Wildwood, New Jersey; and Davenport, Iowa on May 16, June 21, July 20 and 23, 1975.


title: Alive! (Kiss album)

text: The album's title was a homage to the 1972 live album "Slade Alive!" from the English rock group Slade, a band that heavily influenced Kiss.


title: Alive! (Kiss album)

text: From 1974 to 1975, Kiss released three albums: "Kiss", "Hotter Than Hell", and "Dressed to Kill". Although the three albums helped establish a cult following for the band in the Rust Belt, they were commercial failures. Guitarist Paul Stanley attributed the low sales to Kiss' weak sound when they were in the studio versus when they were in concert. According to Stanley: "I never thought any of our first three albums captured the intensity of what the band was going for or was. And it was a problem because people would come to see us and many of them weren't buying our albums." Kiss was famous for its elaborate stage performances, where the band members would wear kabuki-style makeup, use pyrotechnics, and spit fake blood. Bassist Gene Simmons said that because of Kiss' notoriety, they were kicked off of multiple tours with groups like Argent, Black Sabbath, and Savoy Brown because they were afraid to play after Kiss.


title: Alive! (Kiss album)

text: Kiss' record label, Casablanca Records, had similar financial issues. By 1974, Casablanca's profits were declining, so CEO Neil Bogart decided to release a double album of from "The Tonight Show Starring Johnny Carson", a show that averaged fourteen million viewers a night. Casablanca shipped 750,000 copies, but the album was an enormous failure. Distributors mailed back their free copies, and Casablanca co-founder Larry Harris said: "It hit the floor with a lifeless, echoing thud." The failure negatively affected many acts signed with Casablanca, including Kiss; the band only received a $15,000 advance for the first three albums, and had yet to receive any royalties. As a result of the breach of contract, Kiss began looking at other labels to sign with, and a lawsuit was eventually filed against Bogart.


title: Alive! (Kiss album)

text: In a last-ditch effort to save the label, Bogart decided to capitalize on Kiss' onstage notoriety and have the band record a live album. Kiss' manager Bill Aucoin was receptive toward the idea, as he felt the band could finally achieve the sound they strove for. He also liked the fact that a live recording would be less expensive than a studio recording. The band members also liked the idea, and within a few days, Bogart arranged the Dressed to Kill Tour. Bogart could not finance the tour, however, so Aucoin paid for the entire tour with his own money, a total of $300,000.


title: Alive! (Kiss album)

text: "Alive!" was recorded over four stops on the Dressed to Kill Tour: May 16 at Cobo Arena in Detroit; June 21 at Cleveland Music Hall in Cleveland; July 20 at RKO Orpheum Theater in Davenport; and July 23 at Wildwoods Convention Center in Wildwood. The seventy-eight-minute double album comprises sixteen songs from the band's first three albums. The live performances featured elaborate setups. For example, during the song "100,000 Years", crew members used flamethrowers to engulf the stage in a ring of fire, and Peter Criss' drum kit rose high above the other band members.


title: Alive! (Kiss album)

text: Kiss' wild and energetic stage presence did not translate well to the live recordings. Stanley and Simmons had several miscues, such as playing the wrong chords, knocking over mics, and not singing directly into the mic. Producer Eddie Kramer knew that significant dubbing was needed to make the album sound good. For many years, Kiss denied the use of dubbing on "Alive!". In Simmons' 2001 autobiography, "Kiss and Make-up: A Memoir", he admitted the band had done some post-production alterations: "There have always been rumors that the "Alive!" record was substantially reworked in the studio. It's not true. We did touch up the vocal parts and fix some of the guitar solos, but we didn't have the time or money to completely rework the recordings. What we wanted, and what we got, was proof of the band's rawness and power." In a 2003 episode of "Ultimate Albums", Kiss fully admitted to overdubbing the album. Stanley said: "What we felt was necessary was to capture the energy of the performance, not necessarily having it note for note of what actually happened." Simmons said: "Most people assume it was all live. It wasn't." Criss said: "We touched up what we had to do and I think it only made it better."


title: Alive! (Kiss album)

text: Kiss rerecorded parts of the album at Electric Lady Studios in August. The live recordings were so heavily altered, only Criss' drum tracks remained untouched. Even the audience was doctored, as Kramer spliced together the best cheers and screams from various Kiss performances. The band wanted the listener to feel like they were in fact in the audience watching the show, and since directly recording an audience would not sound good, this was considered to be the next best solution. Speaking about the heavy studio redubs years later, Kramer said: "Who cares if it was overdubbed? The energy still comes through."


title: Alive! (Kiss album)

text: "Alive!" was released on September 10, 1975. The packaging featured a gatefold sleeve, a tour program with photos, and handwritten notes from the four band members. The first stop for the tour supporting the "Alive!" album was on its release day in Chattanooga, Tennessee. Five days after its release, Aucoin informed Bogart that Kiss were going to leave Casablanca. In response, Bogart signed a two million dollar check to retain the band.


title: Alive! (Kiss album)

text: "Alive!" was originally reissued as a double-CD set in what has now become known as a "Fatboy" 2CD case. When the Kiss back catalog was remastered, it was housed in a slimline 2CD case and, in keeping with the rest of the reissue program, had the artwork restored. "Alive!" was re-released in 2006 as part of the "Kiss Alive! 1975–2000" box set. The short running time of "Alive!" allowed for a single, unedited CD edition in that release. The remastered CD edition eliminated the breaks between the four sides of the original LP release, resulting in that version of the album playing as one continuous performance. The 72-page booklet packaged with the CD set erroneously credited songwriting for "Cold Gin" to Stanley instead of Ace Frehley.


title: Alive! (Kiss album)

text: The album was reissued in 2014 on vinyl with the original artwork and sleeve. The album was reissued again in 2020 for its 45th Anniversary on colored vinyl.


title: Alive! (Kiss album)

text: "Alive!" received negative and mixed reviews from contemporary critics. Alan Niester of "Rolling Stone" judged the band's music to be "awful, criminally repetitive, thuddingly monotonous... and mildly entertaining for about ten minutes", remarking how Casablanca promoted Kiss as "new bad-boy teen idols". "Village Voice" critic Robert Christgau manifested "bemused curiosity" for the album and stated that, while many considered the album to be either "a de facto best-of" or "sludge", he and "the multimillion kids who are buying it don't fall into either category".


title: Alive! (Kiss album)

text: Modern reviews have generally been highly positive. Greg Prato of AllMusic considered "Alive!" to be "Kiss' greatest album ever." In "The New Rolling Stone Album Guide", the album was called "a nonstop Kiss-Krieg of two-note guitar motifs, fake-sounding audience noise, and inspirational chitchat," but also "the next best thing to being there, clearly." Jason Josephes of Pitchfork wrote that "the album may seem like a joke, mainly because it contains every arena rock cliche in the book," but called it "total sonic proof of Kiss climbing their apex." Canadian journalist Martin Popoff remarked how "Alive!" "turned Kiss into an insane rock 'n' roll phenomenon" by elevating what were "economical and low-key hard rock ditties for kiddies" to "larger-than-life status, each now a bombastic track enveloped in fire-breathing mayhem, exploding smokebombs and screaming, hysterical crowds way too high in the mix."


title: Alive! (Kiss album)

text: "Alive!" peaked at No. 9 on the "Billboard" 200 album charts, and charted for 110 weeks, by far the longest chart run in the band's history.


title: Alive! (Kiss album)

text: In 2003, the album was ranked No. 159 on "Rolling Stone" magazine's list of the 500 greatest albums of all time, maintaining the rating in a 2012 update, and dropping to number 305 in the 2020 revision. In 2006, it was placed at No. 26 on "Guitar World" magazine's list of the 100 Greatest Guitar Albums of All Time. In 2009, the same magazine placed it at No. 3 on their list of Top 10 Live Albums.


title: Alive! (Kiss album)

text: ""Alive!" was the first album I ever bought," Soundgarden's Kim Thayil told "Guitar World" in 1992. "And I wasn't alone: you can hear their influence all over metal and punk." Scott Ian and Charlie Benante of Anthrax were immediate fans of the album and "loved every single song on that record."


title: Alive! (Kiss album)

text: The RIAA only acknowledge 500,000 units sold in the United States, even though the album has sold over 9 million copies worldwide. The album has not been re-certified by RIAA after December 4, 1975, 3 months after it was originally released. Soundscan figures from 2007 add another 258,000 in US sales between 1991 and 2006, making it the band's fourth best selling pre-1991 album.


title: Diagram

text: A diagram is a symbolic representation of information using visualization techniques. Diagrams have been used since prehistoric times on walls of caves, but became more prevalent during the Enlightenment. Sometimes, the technique uses a three-dimensional visualization which is then projected onto a two-dimensional surface. The word "graph" is sometimes used as a synonym for diagram.


title: Diagram

text: In science the term is used in both ways. For example, Anderson (1997) stated more generally: "diagrams are pictorial, yet abstract, representations of information, and maps, line graphs, bar charts, engineering blueprints, and architects' sketches are all examples of diagrams, whereas photographs and video are not". On the other hand, Lowe (1993) defined diagrams as specifically "abstract graphic portrayals of the subject matter they represent".


title: Diagram

text: In the specific sense diagrams and charts contrast with computer graphics, technical illustrations, infographics, maps, and technical drawings, by showing "abstract rather than literal representations of information". The essence of a diagram can be seen as:


title: Diagram

text: Or in Hall's (1996) words "diagrams are simplified figures, caricatures in a way, intended to convey essential meaning". These simplified figures are often based on a set of rules. The basic shape according to White (1984) can be characterized in terms of "elegance, clarity, ease, pattern, simplicity, and validity". Elegance is basically determined by whether or not the diagram is "the simplest and most fitting solution to a problem".


title: Diagram

text: Diagrammatology is the academic study of diagrams. Scholars note that while a diagram may look similar to the thing that it represents, this is not necessary. Rather a diagram may only have structural similarity to what it represents, an idea often attributed to Charles Sanders Peirce. Structural similarity can be defined in terms of a mapping between parts of the diagram and parts of what the diagram represents and the properties of this mapping, such as maintaining relations between these parts and facts about these relations. This is related to the concept of isomorphism, or homomorphism in mathematics.


title: Diagram

text: Sometimes certain geometric properties (such as which points are closer) of the diagram can be mapped to properties of the thing that a diagram represents. On the other hand the representation of an object in a diagram may be overly specific and properties that are true in the diagram may not be true for the object the diagram represents. A diagram may act as a means of cognitive extension allowing reasoning to take place on the diagram based on which constraints are similar.


title: Diagram

text: Many of these types of diagrams are commonly generated using diagramming software such as Visio and Gliffy.


title: Diagram

text: Diagrams may also be classified according to use or purpose, for example, explanatory and/or how to diagrams.


title: American football rules

text: Gameplay in American football consists of a series of "downs", individual plays of short duration, outside of which the ball is "dead" or not in play. These can be plays from scrimmage – passes, runs, punts, or field goal attempts (from either a place kick or a drop kick) – or free kicks such as kickoffs and fair catch kicks. Substitutions can be made between downs, which allows for a great deal of specialization as coaches choose the players best suited for each particular situation. During a play, each team should have no more than 11 players on the field, and each of them has specific tasks assigned for that specific play.


title: American football rules

text: The objective of this game is to score more points than the other team during the allotted time. The team with the ball (the "offense") has 4 plays ("downs") to advance at least 10 yards, and can score points once they reach the opposite end of the field, which is home to a scoring zone called the "end zone", as well as the goalposts. If the offense succeeds in advancing at least 10 yards, they earn a "first down" and the number of tries allotted is reset and then they are again given 4 tries to advance an additional 10 yards, starting from the spot to which they last advanced. If the offense does not advance at least 10 yards during their 4 downs, the team without the ball (the "defense") regains control of the ball (called "turnover on downs").


title: American football rules

text: On offense, points are scored by advancing the ball into the opponent's end zone for a "touchdown" (worth six points), or by kicking the ball from the playing field through the raised vertical posts (the "goalposts") which are most commonly situated on the end line of the end zone for a "field goal" (worth three points). After scoring a touchdown, the offense is given an additional opportunity from the 2-yard line (3-yard line in amateur football) to attempt to score (in the NFL, 15-yard line on 1-point conversions). Conversion attempts are used to score 1 or 2 points as follows:


title: American football rules

text: While the opposing team has possession, the defense attempts to prevent the offense from advancing the ball and scoring. If an offensive player loses the ball during play (a "fumble") or the ball is caught by a defensive player while still in the air (an "interception"), the defense may attempt to run into the offense's end zone for a touchdown. The defense may also score points by tackling the ball carrier in the offense's own end zone, called a "safety" (which is worth two points).


title: American football rules

text: Collegiate and professional football games are 1 hour long, divided into four quarters of 15 minutes each. In high school football, 12 minute quarters are usually played. The clock is stopped frequently, however, with the result that a typical college or professional game can exceed three hours in duration. The referee controls the game clock and stops the clock after any incomplete pass or any play that ends out of bounds. In addition, each team is allowed 3 timeouts in each half that they may use at their own discretion. The clock normally runs during the action of plays, with a few exceptions known as untimed plays. Some high schools employ a mercy rule in which the clock runs continuously after one team's lead over the other achieves a certain number of points. In these instances, the clock only stops for injuries, or time outs called by a team or a referee.


title: American football rules

text: The clock may also be stopped for an officials' time-out, after which, if the clock was running, it is restarted. For example: if there is a question whether or not a team has moved the ball far enough for a first down, the officials may use a measuring device ("the chains") to determine the distance. While this measurement is taking place, the officials will signal for a stoppage of the clock. Once the measurement is finished and the ball is placed at the proper location ("spotted"), the referee will then signal for the clock to restart. Additional situations where officials may take a time-out are to administer a penalty or for an injured player to be removed from the field.


title: American football rules

text: In addition to the game clock, a separate "play clock" is also used. This counts down the time the offense has to start the next play before it is assessed a penalty for delay of game (see below). This clock is typically 25 seconds from when the referee marks the ball ready for play. The NFL and NCAA use a 40-second play clock that starts immediately after the previous play ends, though, for certain delays, such as penalty enforcement, the offense has 25 seconds from when the ball is marked ready. The purpose of the play clock is to ensure that the game progresses at a consistent pace, preventing unnecessary delays. Overall, clock management is a significant part of the game; teams leading toward the end of the game will often try to run out the clock via kneeldown while trailing teams attempt the opposite.


title: American football rules

text: Officials also call for media time-outs, which allow time for television and radio advertising. They also stop the clock after a change of possession of the ball from one team to the other. Successful PATs (Point(s) After Touchdown), a field goal try, or a kickoff may also warrant stopping the clock. If an instant replay challenge is called during the game, the referees signal for a media time out. The referee signals these media time-outs by first using the time out signal, then extending both arms in a horizontal position.


title: American football rules

text: Teams change ends of the field at the end of the first quarter and the end of the third quarter, though otherwise, the situation on the field regarding possession, downs remaining and distance-to-goal does not change at these occasions (so a team with possession 5 yards from the opponent's endzone at the end of the first quarter would resume playing 5 yards from the endzone at the other end of the field, which they would then be attacking). Separating the first and second halves is "halftime." Both halves, and any overtime, begin with kick-offs — the kicking team is decided by a coin toss (see below).


title: American football rules

text: In the NFL, an automatic timeout is called by the officials once the ball is dead and there are two minutes or less left in both the second and the fourth quarters, and overtime; this is most commonly referred to as the "two-minute warning." No such warning is normally given in amateur football, though if there is no visible stadium clock, the referee will give a two-minute warning (four minutes in high school).


title: American football rules

text: If a game is tied at the end of four quarters, "overtime" is played. In overtime, a coin toss is used to determine which team will possess the ball first. The winner of the coin toss can choose to give the ball or receive the ball. If the first possession results in a touchdown (by the receiving team or by the defensive team on a turnover) or defensive team scores a safety, the scoring team wins. If the receiving team fails to score and loses possession, the game goes into sudden death, and first to score wins.


title: American football rules

text: However, if the initial receiving team only scores a field goal, the game is not automatically over and the other team is given an opportunity to possess the ball as well. The other team can win with a touchdown, tie with a field goal leading to sudden death or lose if they fail to score.


title: American football rules

text: During the regular season in the NFL, one overtime period is played (with each team receiving two-time outs). If the game is still tied after the 10-minute overtime, the game officially ends in a tie. Before the season, there was 15-minute overtime. In the playoffs, 15-minute overtime periods continue until a winner is determined. Overtime follows a three-minute intermission after the end of the regulation game. Prior to the start of overtime, a coin flip is performed in which the captain of the visiting team calls the toss. The team that wins the coin flip has the option either to receive the kickoff or choose the side of the field they wish to defend. Ties are rare in the NFL; the most recent being a game between the Washington Commanders and New York Giants on December 4, 2022, which ended in a 20–all tie. See List of NFL tied games for more games.


title: American football rules

text: Prior to the 2010-11 playoffs, the overtime winner was simply the first team to score any points; however, the rules were changed to reduce the advantage obtained by the team that won the overtime coin toss. Under the prior rules, the team that won the coin toss would usually elect to receive the ball, then gain just enough yardage to win the game by kicking a field goal without the other team ever touching the ball. The coin toss winner won approximately 60% of overtime games under that rule, rather than the 50% which would be expected by random chance.


title: American football rules

text: The first overtime game played under a trial of the new overtime rules occurred in a between the Denver Broncos and Pittsburgh Steelers at Sports Authority Field at Mile High, Denver, Colorado. Denver won the game on the first play in overtime, an 80-yard touchdown pass from Tim Tebow to Demaryius Thomas. The rule was formally adopted for the 2012 season, and the first game in which both teams scored in overtime was a 43–37 victory by the Houston Texans over the Jacksonville Jaguars on November 18, 2012.


title: American football rules

text: The rules for overtime changed for the 2016–2017 season and were tweaked again for the 2017–2018 season. The NFL's overtime rules are still subject to criticism, as a team that loses the coin toss and goes on to concede the touchdown does not get a chance for their offense to take the field.


title: American football rules

text: Super Bowl LI was the first Super Bowl to go into overtime with a 28-all tie between the Atlanta Falcons and New England Patriots, which the Patriots eventually won with James White scoring a touchdown on the Patriots' first drive.


title: American football rules

text: The 2019 NFC and AFC championship games both went to overtime, the first time for such an occurrence. In the NFC title game, the New Orleans Saints won the coin toss but an interception allowed the Los Angeles Rams to drive into range to kick the winning field goal. In the AFC Championship held later that day, the New England Patriots won the coin toss and on their first drive scored the winning touchdown over the Kansas City Chiefs.


title: American football rules

text: NFL Europa, a defunct league run by the NFL, used a 10-minute overtime period, with the constraint that each team must have the opportunity of possession; once both teams have had such an opportunity, the overtime proceeds in a manner similar to the NFL's. Thus, if Team A has the first possession of overtime and scores a touchdown and converts their kick (thus being 7 points ahead of Team B), Team A would then kick off to Team B (In the NFL, the game would have ended with the touchdown, without a conversion being attempted). Team B would have to match or exceed the 7 point difference within this ensuing possession; exceeding it would end the game immediately while matching the difference would result in a kickoff to Team A. From this point, the overtime is sudden death. The defunct United Football League had also used this rule.


title: American football rules

text: The defunct World Football League, in its first season of 1974, used an overtime system more analogous to the system long used in international soccer. The overtime consisted of one 15-minute period, which was played in its entirety and divided into two halves of 7½ minutes each, with each half starting with a kickoff by one of the teams. The league changed to the NFL's sudden-death format for its final season in 1975.


title: American football rules

text: In college and high school football, an overtime procedure (the "Kansas plan") ensures that each team has equal opportunity to score. In college, both teams are granted possession of the ball at their opponents' 25 yard-line in succession; the procedure repeats for next possession if needed; all possessions thereafter will be from the opponent's 3-yard line. A coin flip takes place, with the winning team having the option either 1) to declare that they will take the ball first or second, or 2) to decide on which end of the field the series will occur (both teams' series occur on the same end of the field). The losing team will have the first option in any subsequent even-numbered overtime. In the first overtime, the team with the first series attempts to score either a touchdown or a field goal; their possession ends when either a touchdown or a field goal have been scored, they turn the ball over via a fumble or an interception, or they fail to gain a first down. After a touchdown, a team may attempt either an extra-point or a two-point conversion. However, if the team on defense during the first series recovers a fumble and returns it for a touchdown, or returns an interception for a touchdown, the defensive team wins the game. (This is the only way for a college overtime game to end without both teams having possession.) Otherwise, regardless of the outcome of the first team's series (be it a touchdown, field goal, or turnover), the other team begins their series. If the score remains tied after both teams have completed a series, the procedure is repeated, but if a touchdown is scored, a two-point conversion will be required. Since 2021, if the game is still tied after double overtime, each team attempts one 2-point conversion per period rather than getting the ball at the 25-yard line.


title: American football rules

text: In high school football, individual state associations can choose any overtime format they want, or even elect to not play overtime at all (ties stand in this case). However, most states use the Kansas Plan. In a majority of states, each team is granted possession of the ball at the 10-yard line, meaning that a team cannot make a first down without scoring except via a defensive penalty that carries an automatic first down (such as defensive pass interference or roughing the passer). As is the case with the college overtime rule, the team that wins the coin toss will have the choice as to whether to take the ball first or second, or decide at which end of the field the overtime will be played. The other major difference between overtime in college football and high school football is that in some states, if the defense forces a turnover, the ball is dead immediately, thus eliminating the possibility of scoring. However, in Texas, the college overtime rule is used, as both the University Interscholastic League, which governs interscholastic activities for Texas public high schools, and the Texas Association of Private and Parochial Schools, the largest analogous body for Texas private high schools, play by NCAA football rules with a few modifications for the high school level.


title: American football rules

text: The original incarnation of the XFL used a modified Kansas Plan which, upon the first team scoring, required the opponent to score the same or greater number of points in the same or fewer downs (i.e., if the first team scored a touchdown, and converted the one-point conversion in three downs, the opponent would have to match that touchdown and conversion in three downs as well). Each team started at the 20-yard line, but like high school, there were no opportunities for first downs. The league also banned field goals except on a fourth down.


title: American football rules

text: The XFL's current incarnation uses a five-round shootout of two-point conversions similar to a penalty shootout in soccer or ice hockey. Such a shootout had never been attempted in organized football at the time the rule was proposed; in April 2019, the NCAA adopted a similar concept for games that reach quintuple overtime starting with the 2019 FBS season, two seasons later, triple overtime. The defense is not able to score, as should a turnover occur, the play would be dead. Defensive penalties result in the ball moving up to the 1-yard line, while a second defensive penalty on any play, even in future rounds, results in a score awarded to the offensive team. To speed up the overtime process, both teams' offense and defense are on the field at the appropriate end zone. Once one team's offense has completed its round of the shootout, the other team's offense plays its round from the opposite end zone. These overtime rules ensure that both teams have an opportunity to win the game and would limit overtime to 5 or 6 minutes. If both teams remain tied after five rounds, multiple rounds of conversions will be played until one team succeeds, thus ensuring that no game can end in a draw.


title: American football rules

text: The United States Football League settles ties this way: teams get three (at least two) rounds of two-point conversions from the three-yard line. Coin toss is called by the visiting team; winner of the toss can choose to possess the ball first or defend. Whoever scores more points in the three rounds wins it; otherwise, teams play sudden-death rounds until one team scores. One timeout can be called per overtime round. Although no game clock is used, the play clock of 35 seconds is still used.


title: American football rules

text: Three minutes before the start of the game, the referee meets with captains from both teams for a coin toss. The visiting team calls the toss before the coin is flipped, since 1996. The winner of the toss may defer their choice to the start of the second half, or they may take the first choice of:


title: American football rules

text: At the start of the second half, the team that did not choose first (either because they deferred their choice or because they lost the toss) gets the first choice of options.


title: American football rules

text: According to "USA Today", in college games, the team that wins the toss defers their choice to the start of the second half over 90% of the time.


title: American football rules

text: If a game goes to overtime, a coin toss is held before the start of overtime, but tosses are not held before the start of subsequent overtime periods. In college, for example, the loser of the toss to start overtime has the first choice in the second overtime period. The choices available to the captains in overtime vary among the NFL, college, and various states' high school rules.


title: American football rules

text: In high school, the coin toss may be held between the captains or coaches earlier before the start of the game. At three minutes before kickoff, the captains meet for a simulated coin toss, where the referee announces the results of the earlier toss.


title: American football rules

text: The original incarnation of the XFL did not implement a coin toss; instead, an event took place called the "opening scramble", in which one player from each team fought to recover a football 20 yards away to determine possession. Both players lined up side-by-side on one of the 30-yard lines, with the ball being placed at the 50-yard line. At the whistle, the two players would run toward the ball and attempt to gain possession; whichever player gained possession first was allowed to choose possession (as if he had won a coin toss in other leagues).


title: American football rules

text: The XFL's current incarnation also does not feature coin tosses. Instead, the home team is given the option to kick off, receive, select a goal, or defer to the second half. In the event of overtime, the visiting team is given the choice of going first or second or selecting which end zone to attack (with the home team getting the other choice).


title: American football rules

text: The rules vary from the college level to the professional level. In the NFL, unless a player is tagged by an opposing player or gives himself up, he is not down. A player carrying the ball (the runner) is downed when any of the following occurs:


title: American football rules

text: The majority of a football game takes place on plays, or "downs", that begin at the line of scrimmage. The officials "spot" the ball (place it in a designated spot on the field) on the line of scrimmage and declare it ready for play.


title: American football rules

text: The width of the spotted football defines the width of the neutral zone, an area of the field no player other than the snapper may position himself in or above before the snap. Each team has its own line of scrimmage, thought of as a vertical plane from sideline to sideline that passes through the point of the ball nearest its own goal line.


title: American football rules

text: A typical offense is made up of a quarterback, five offensive linemen, two wide receivers, a running back, a fullback, and a tight end, however teams will vary their personnel on the field to fit any given play. A quarterback is essentially the leader of the offense. It is most often their responsibility to pass along the play called to the rest of the players in the huddle before any given play. A quarterback is the primary ball-handler on offense. It is their responsibility to call the snap count for the ball to enter play. Once the ball is hiked into play, it is their job to either hand the ball off to one of their running backs, or scout the field for an open receiver to throw the ball to. In some instances, the quarterback will run the ball themselves. A quarterback is guarded by their offensive linemen. The offensive line is made up of a left and right tackle, a left and right guard, and a center. It is the center's responsibility to hike the ball to the quarterback. An offensive line has two different jobs. When the offense runs a pass play, it is their job to guard the quarterback from the defense that is rushing. When the offense runs a run play, it is their job to clear a path for the running back to run through. The running back also has multiple roles. They will either take the ball from the quarterback and run, move up and help the offensive line block or go out and catch a pass. While the role of the fullback is deteriorating currently among professional leagues, it is their primary responsibility to lead the running back. Running backs and fullbacks are sometimes also called a halfback, a wingback, or a slotback. Like the running back, the tight end also has multiple roles. They will either help the offensive line protect the quarterback, block on run plays, or run or catch the ball themselves. The wide receivers' primary role is to run out into the field of play and catch the ball, although they will also block in some instances.


title: American football rules

text: The players on offense must arrange themselves in a formation, all behind their line of scrimmage (that is, on their side of the ball). For reasons of safety and competitive balance, there are strict rules which define the way in which the offensive players may line up. Seven players must line up directly on the line of scrimmage while four players line up behind the line of scrimmage. Within this formation, there are six eligible receivers who may receive a forward pass during play. These eligible receivers are either the running back, fullback, tight end, or wide receivers. The remaining five linemen, often called "interior linemen" do not normally handle the ball during a play. Because of these rules, various leagues of American football have enacted strict rules of uniform numbering so officials may more easily judge which players were eligible and which were not at the start of a play. For example, in college football, ineligible players wear numbers 50–79, while eligible receivers wear 1–49 or 80–99. Even within this structure, offenses can still present a wide number of formations, so long as they maintain the "seven and four" arrangement. Receivers, for example, may play close to the other linemen or they may play some distance down the line of scrimmage, where they would sometimes be called split ends. Of the four backs, they may play behind the linemen or may play "split out" to provide additional wide receivers. These additional receivers can be flankers (if they play split far wide, but still in the backfield) or slot receivers if they play in the "slot" between the split end and the rest of the offensive line.


title: American football rules

text: The players on defense may arrange themselves in any manner, as long as all players are "behind the line" (that is, on the side of the line nearest their own end zone). Players who line up opposite the offensive line are called defensive linemen, usually with one or two defensive tackles in the middle (a single defensive tackle is often called the nose guard or nose tackle) and with one defensive end on each side. A defensive lineman's job is typically to put pressure on the opposing team's quarterback by rushing the offensive line. The defensive line is also most often the first set of players the opponent must get through should they choose to run the ball. Behind the linemen are the linebackers. A linebacker's job can be any number of things, including trying to rush the opposing team's quarterback, stopping the opponents running back on run plays, or covering the opponent's tight end or wide receivers. Positioned opposite the wide receivers are the cornerbacks. Their primary responsibility is to cover the wide receivers. Farthest back from the line are the safeties, usually in the middle of the field behind the linebackers. The safeties are the last line of defense against the opponent. Like a linebacker, a safety's role can vary, however, their most common role is to help the cornerbacks cover the opponent's wide receivers, which is called "double coverage". The linemen and linebackers close to the line of scrimmage, are often referred to as playing "in the box". Players outside "the box" (usually cornerbacks and safeties) are collectively referred to as the "secondary".


title: American football rules

text: A scrimmage down begins with a "snap", where the center throws or hands the ball back to one of the backs, usually the quarterback. The quarterback then either hands the ball off to a back, throws the ball, or runs with it himself. The down ends when the ball becomes dead (see below). The ball is typically next spotted where the ball became dead; however, if it became dead outside the hash marks, it is brought in on the same yard line to the nearest hash mark. This spot becomes the line of scrimmage for the next play. In the case of an incomplete forward pass, the ball is returned to the spot where it was last snapped to begin the next play. A fumbled ball that goes out of bounds is declared dead and possession remains with the team that most recently had control of the ball.


title: American football rules

text: The nearest official typically blows his whistle after the ball becomes dead to alert the players that the down has already ended. If the ball is alive and the official sounds an "inadvertent whistle", then the ball still becomes dead, but the team in possession of the ball may elect to have the down replayed or take the spot where the ball was declared dead. If the ball was loose from a fumble, then the ball can be put into play at the spot of the fumble. If the ball was in flight from a kick or a pass, then the down is always replayed.


title: American football rules

text: A free kick is a down that does not occur from scrimmage. The kicking team begins behind the ball, while the receiving team must remain at least 10 yards downfield before the ball is kicked.


title: American football rules

text: A kickoff is a type of free kick where the ball is placed on a tee (or held) at the kicking team's 35-yard line (40 for high school). In the 2011 NFL Season, changes were made regarding kickoffs to limit injuries. The spot from which the ball is kicked was restored to the 35 yard line, bringing to an end the 1994 designation of the 30 yard line, a change meant to increase the frequency of the option to elect a touchback. In addition, players on the kickoff coverage team (apart from the kicker) cannot line up more than a specified distance behind the kickoff line. This distance is 5 yards at most levels of the game and 1 yard in the NFL, minimizing running starts and thus reducing the speed of collisions. The kicking team's players may not cross this line until the ball is kicked; members of the non-kicking (or "receiving") team are similarly restrained behind a line 10 yards further downfield (the 45-yard line, or 50 for high school). A valid kickoff must travel at least this 10-yard distance to the receiving team's restraining line, after which any player of either team may catch or pick up the ball and try to advance it (a member of the kicking team may only recover a kickoff and may not advance it) before being downed (see "Downed player," below). In most cases, the ball is kicked as far as possible (typically 40 to 70 yards), after which a player of the receiving team is usually able to secure possession (since the members of the kicking team cannot start downfield until after the ball is kicked). Occasionally, for tactical reasons, the kicking team may instead choose to attempt an onside kick, in which the kicker tries to kick the ball along the ground just over the required 10-yard distance in such a manner that one of his own teammates can recover the ball for the kicking side. If it is touched before ten yards, the ball is dead and a re-kick or spot of the ball will be rewarded to the receiving team.


title: American football rules

text: A member of the receiving team gaining possession of the ball on a kickoff may attempt to advance it as far as he can toward the kicking team's goal line before being downed. Once the ball carrier is downed, the play is whistled dead and the ball is placed by the officials at the point where the play ended; this spot then becomes the line of scrimmage for the ensuing play. A kick that travels through or goes out of bounds within the end zone without being touched, or is caught by the receiving team in the end zone but not advanced out of it, results in a touchback; the ball is then placed at the receiving team's 25-yard line, which becomes the line of scrimmage. In college football only, a fair catch by the receiving team between its own 25-yard line and the goal line is treated as a touchback, with the ball placed at the 25.


title: American football rules

text: A kickoff that goes out of bounds anywhere other than the end zone before being touched by the receiving team is an illegal kick: the receiving team has the option of having the ball re-kicked from five yards closer to the kicking team's goal line, or they may choose to take possession of the ball at the point where it went out of bounds or 30 yards from the point of the kick (25 yards in high school, and in college ), whichever is more advantageous.


title: American football rules

text: A free-kick is also used to restart the game following a safety. The team that was trapped in its own end zone, therefore conceding two points to the other team, kicks the ball from its own 20-yard line. This can be a place kick (in the NFL, a tee cannot be used), drop-kick, or punt.


title: American football rules

text: In the NFL and high school, a free kick may be taken on the play immediately after a fair catch; see "fair catch kick" below.


title: American football rules

text: Most standard football plays are considered scrimmage plays, initiated from a line of scrimmage. Exceptions are kickoffs and try plays (below). Although similar rules apply during a try play, the number of points awarded for each score differs on a try play.


title: American football rules

text: A touchdown is earned when a player has legal possession of the ball and the ball touches or goes over the imaginary vertical plane above the opposing team's goal line. After a touchdown, the scoring team attempts a try play for 1 or 2 points (see below). A successful touchdown is signaled by an official extending both arms vertically above the head. A touchdown is worth six points, except in the defunct WFL where it was worth seven points.


title: American football rules

text: For statistical purposes, the player who advances the ball into or catches it in the end zone is credited with the touchdown. If a forward pass was thrown on the play, the throwing player is credited with a passing touchdown.


title: American football rules

text: A field goal is scored when the ball is place kicked, drop kicked, or free kicked after a fair catch or awarded fair catch (High School or NFL only) between the goalposts behind the opponent's end zone. The most common type of kick used is the place kick. For a place kick, the ball must first be snapped to a placeholder, who holds the ball upright on the ground with his fingertip so that it may be kicked. Three points are scored if the ball crosses between the two upright posts and above the crossbar and remains over. If a field goal is missed, the ball is returned to the original line of scrimmage (in the NFL, to the spot of the kick; in high school, to the 20-yard line if the ball enters the end zone, or otherwise where the ball becomes dead after the kick) or to the 20-yard line if that is further from the goal line, and possession is given to the other team. If the ball does not go out of bounds, the other team may catch the kicked ball and attempt to advance it, but this is usually not advantageous. One official is positioned under each goalpost; if either one rules the field goal no good, then the field goal is unsuccessful. A successful field goal is signaled by an official extending both arms vertically above the head. A team that successfully kicks a field goal kicks off to the opposing team on the next play.


title: American football rules

text: The uncommon safety is scored if a player causes the ball to become dead in his own end zone; two points are awarded to the opposing (usually defending) team. This can happen if a player is either downed or goes out of bounds in the end zone while carrying the ball, or if he fumbles the ball, and it goes out of bounds in the end zone. Safety is also awarded to the defensive team if the offensive team commits a foul which is enforced in its own end zone. A safety is "not" awarded if a player intercepts a pass or receives a kick in his own end zone and is downed there. This situation, in which the opponent caused the ball to enter the end zone, is called a touchback; no points are scored, and the team that gained possession of the ball is awarded possession at its own 25-yard line. If the interception or reception occurs outside the end zone, and the player is carried into the end zone by momentum, the ball is placed at the spot of the catch, and no safety is awarded. A safety is signaled by a referee holding both palms together above the head, fingertips pointing upwards. After a safety, the team that conceded the safety kicks a free kick (which may be a punt, place kick, or drop-kick) from its 20-yard line.


title: American football rules

text: A try play (as opposed to a regular scrimmage play or kickoff), more commonly referred to as an extra-point attempt, PAT (abbreviation of "point after touchdown"), conversion attempt, or two-point conversion attempt, based on the scoring team's intentions on the play, is awarded to the scoring team immediately following a touchdown. This un-timed down is an opportunity to score additional points.


title: American football rules

text: The offensive team may attempt to kick the ball through the goalposts, in the same manner, that a field goal is kicked during a scrimmage play. In the NFL, the ball is spotted at the 15-yard line. In college and high school, the ball is spotted at the 3-yard line. If successful, the team is awarded 1 point, referred to as an extra point. This option is almost always chosen because a two-point conversion attempt is much riskier. Since the extra point is almost always successful, sportscasters will often refer to a team-up or trailing by seven (not six) points as being "up/trailing by a touchdown".


title: American football rules

text: The offensive team may attempt to advance the ball via run or pass into the end zone, much like a touchdown on the extra-point attempt, except that it receives two points. This is called a two-point conversion. If the offense elects to attempt a two-point conversion on the try play, the ball is spotted at the 2-yard line in the NFL and on the 3-yard line for college and high school. The success rate for two-point conversions is about 48 percent in the NFL, making the two-point conversion attempt a risky tactic; thus it is usually attempted only when two points will help the team but one point will not.


title: American football rules

text: Under college, NFL & USFL rules, if the defensive team gains possession and advances the ball the length of the field into the opposite end zone on the try play (via interception or a fumble recovery, or by blocking a kick and legally recovering the ball), they score two points. This is officially recorded as a defensive conversion scored by the defense. The NCAA adopted this rule in 1988; the NFL added this in 2015; the USFL, 2022.


title: American football rules

text: A safety scored on a try play is worth one point. This can occur when, for example, the defense gains control of the ball and advances it into the field of play, but then retreats into its own end zone when play is stopped. Similarly, the defense could recover a fumble in its own end zone before play is stopped. A safety on a try play could also be awarded to the defense if the defense takes possession of the ball during a try play, advances it all the way down to the opposite end of the field, where the offensive team then regains possession before the play is declared dead in that end zone.


title: American football rules

text: The officials' signal for a successful try, whether an extra point or a two-point conversion, is the same as for a touchdown. The officials' signal for a safety on a try play is also the same as on a scrimmage play.


title: American football rules

text: After the try, the team that scored the touchdown kicks off to the opposing team. Unlike a safety that occurs on a scrimmage play, no free-kick is awarded following a safety on a try play.


title: American football rules

text: During sudden-death over time, particularly in the NFL, if a team scores a touchdown in the overtime period, the game is immediately over, and the try is ignored.


title: American football rules

text: In NCAA overtime, if the second team to possess the ball in the overtime scores a touchdown which puts them ahead of the opponent in points, the game is immediately over, and the try is ignored.


title: American football rules

text: A free-kick (see above) may be taken on the play immediately after any fair catch of a punt. In the NFL, if the receiving team elects to attempt this and time expired during the punt, the half/overtime is extended with an untimed down. The ball must be held on the ground by a member of the kicking team or drop kicked; a tee may not be used. (High school kickers may use a tee). This is both a field goal attempt and a free-kick; if the ball is kicked between the goalposts, three points are scored for the kicking team. This is the only case where a free kick may score points. This method of scoring is extremely rare, last successfully completed in the NFL by Ray Wersching in 1976. It is only advantageous when a team catches a very short punt with very little time left. A team is unlikely to be punting with only a few seconds left in a half or overtime, and it is rarer still for punts to be caught near field goal range. The officials' signal for a successful fair catch kick is the same as for a field goal.


title: American football rules

text: The game is officiated by a crew of three to seven officials. Every crew will consist of a "referee", who is generally in charge of the game and watches the action on the quarterback and in the offensive backfield; an "umpire", who handles spotting the ball and watches the action on the offensive line; and a "head linesman", who supervises the placement of the down box and line-to-gain chains. The crew may also consist of a "line judge", "back judge", "field judge" and "side judge", in the order listed: i.e. a crew of five officials have a referee, umpire, head linesman, line judge, and back judge.


title: American football rules

text: Officials are selected by the teams in advance or appointed by the governing league. While the majority of officials at lower levels only officiate games on a part-time basis, the NFL is implementing a new system where seven officials will become full-time employees of the league, one for each official position (i.e. back judge, field judge, side judge, etc.). In the other three major North American professional sports leagues – Major League Baseball, the NBA and NHL – officials are employed by their respective leagues. The sheer volume of games in the other three sports necessitates full-time officials; since 2021, the NFL regular season is only 17 games long, compared to 162 games for MLB and 82 for the NBA and NHL.


title: American football rules

text: During the game, the officials are assisted in the administration of the game by other persons, including a "clock operator" to start and stop the game clock (and possibly also the play clock); a chain crew who hold the " down indicator" and the "line-to-gain chains" on the sideline; and "ball boys", who provide footballs to officials between downs (e.g. a dry ball each down on a wet day). These individuals may be provided by the teams involved – it is common for a high school coach's son or daughter to act as a ball boy for the team.


title: American football rules

text: Because football is a high-contact sport requiring a balance between offense and defense, many rules exist that regulate equality, safety, contact, and actions of players on each team. It is very difficult to always avoid violating these rules without giving up too much of an advantage. Thus, an elaborate system of fouls and penalties has been developed to "let the punishment fit the crime" and maintain a balance between following the rules and keeping a good flow of the game. Players are constantly looking for ways to find an advantage that stretches the limitations imposed by the rules. Also, the frequency and severity of fouls can make a large difference in the outcome of a game, so coaches are constantly looking for ways to minimize the number and severity of infractions committed by their players.


title: American football rules

text: It is a common misconception that the term "penalty" is used to refer both to an infraction and the penal consequence of that infraction. A "foul" is a rule infraction for which a penalty is prescribed. Some of the more common fouls are listed below. In most cases when a foul occurs, the offending team will be assessed a penalty of 5, 10, or 15 yards, depending on the foul. Also, in most cases, if the foul is committed while the ball is in play, the down will be replayed from the new position (for example, if the offense commits a foul on a first-down play, the next play will still be first down, but the offense may have to go 15 yards, or farther, to achieve another first down.) But if a defensive foul results in the ball advancing beyond the offense's first-down objective, the next play will be the first down of a new series. Some penalties (typically for more serious fouls), however, require a loss of down for the offense; and some defensive fouls may result in an automatic first down regardless of the ball position.


title: American football rules

text: In all cases (except for ejection of a player or, in rare cases, forfeiture of the game), the non-offending team is given the option of declining the penalty and letting the result of the play stand (although the Referee may exercise this option on their behalf when it is obvious), if they believe it to be more to their advantage. For some fouls by the defense, the penalty is applied in addition to the yardage gained on the play. Most personal fouls, which involve danger to another player, carry 15-yard penalties; in rare cases, they result in offending players being ejected from the game. In the NFL, if a defensive foul occurs after time has expired at the end of a half, the half will be continued for a single, untimed play from scrimmage. Under college rules, any accepted penalty when the time has expired at the end of any quarter results in an extension for one untimed down.


title: American football rules

text: In the NFL, with three exceptions, no penalty may move the ball more than half the distance toward the penalized team's goal line. These exceptions are defensive pass interference (see the discussion of that foul for more details), intentional grounding, and offensive holding – but in this last case, the exception pertains only if the infraction occurs within the offensive team's own end zone, in which case an automatic safety is assessed (intentional grounding from the end zone also carries an automatic safety). Under college rules, the same half-the-distance principle applies, but any offensive fouls involving contact in their end zone (e.g. holding, illegal blocking or personal fouls) result in a safety.


title: American football rules

text: Each team receives three timeouts per half (if the game goes to overtime, each team receives additional timeouts), making for a total of six timeouts per team in a regulation game. Unused timeouts may not carry over to the second half or overtime. In professional football, a team must have at least one remaining timeout to challenge an official's call.


title: American football rules

text: In the NFL, a number of rulings can be reviewed by officials or challenged by coaches. If a coach wants to challenge a play, he must do so before the next play begins, and he does so by throwing a red flag similar to the officials' yellow flags. Coaches are allowed two challenges per game and are granted a third if their first two are successful. The team loses a timeout if they lose the challenge. Therefore, they cannot challenge if they do not have timeouts. Plays within the two-minute-warning and overtime cannot be challenged; any review must be initiated by a replay official off-field. The referee performs the actual review via a video screen on the sideline. The referee will announce the result of instant replay reviews over his wireless microphone.


title: American football rules

text: Beginning in the 2011 NFL Season, an instant replay review by the booth official will now be automatic for every play ruled by the referees on the field to have scored points. This is seen as another step in the "modernization" of sports. Every scoring play will be reviewed now, which saves coaches from using up their challenges on close plays in the endzone. And since the 2012 season, the booth official also reviews all turnovers during the game.


title: American football rules

text: In college, coaches are allowed one challenge per game by first requesting a timeout. Otherwise, a replay official in the press box observes all plays. If he deems a ruling may be in error, he notifies the officials on the field to interrupt the game before the beginning of the next play. The replay official performs the review and relays the decision to the referee, who announces the result. Not every conference employs replay, which is optional.


title: American football rules

text: High school rules generally do not provide for a video review of any decisions by officials during a game. By state adoption, replay may be used in a state championship game. At all times, the use of television or videotape for coaching purposes during the game is prohibited. If a coach feels a rule has been misinterpreted, he may call a timeout and request a coach-referee conference to "discuss" the ruling with the referee, but no replay equipment will be consulted during the conference.


title: Ophir

text: Ophir (; ) is a port or region mentioned in the Bible, famous for its wealth. King Solomon received a shipment from Ophir every three years (1 Kings 10:22) which consisted of gold, silver, sandalwood, pearls, ivory, apes, and peacocks.


title: Ophir

text: Ophir in Genesis 10 (the Table of Nations) is said to be the name of one of the sons of Joktan. The Books of Kings and Chronicles tell of a joint expedition to Ophir by King Solomon and the Tyrian king Hiram I from Ezion-Geber, a port on the Red Sea, that brought back large amounts of gold, precious stones and 'algum wood' and of a later failed expedition by king Jehoshaphat of Judah. The famous 'gold of Ophir' is referenced in several other books of the Hebrew Bible.


title: Ophir

text: In the Septuagint, other variants of the name are mentioned: "Ōpheír", "Sōphír", "Sōpheír" and "Souphír".


title: Ophir

text: The New Testament apocrypha book "Cave of Treasures" contains a passage: "And the children of Ophir, that is, Send, appointed to be their king Lophoron, who built Ophir with stones of gold; now, all the stones that are in Ophir are of gold."


title: Ophir

text: In 1946, an inscribed pottery shard was found at Tell Qasile (in modern-day Tel Aviv), dating to the eighth century BC. It bears, in Paleo-Hebrew script, the text ""gold of Ophir to/for Beth-Horon [...] 30 shekels"" The find confirms that Ophir was a place from which gold was imported.


title: Ophir

text: In 1976, the United States Department of Interior announced that a team formed by the United States Geological Survey together with experts from Saudi Arabia believes it has "a fairly airtight case” that Mahd adh Dhahab, or Cradle of Gold, in Saudi Arabia is the biblical Ophir. As evidence, the team states that "there are huge quantities of waste rock left behind by ancient miners, approximately a million tons, and that it has an average gold content of sixtenths of an ounce per ton, indicating that the mined ore must have been richer. From sampling old slopes and from production figures during the 1939 to 1954 period when the mine was reactivated to extract gold and silver, the geological survey scientists estimated that in biblical times much gold must have been found at or near the surface." Moreover, Mahd adh Dhahab is "within range of Israel's transport capability," and it "could easily have been known to Solomon or his advisers because it lies on a north‐south trade route that has run to Aqaba for some 4,000 years." Their conclusion is that "Mand adh Dhahab [sic] could have produced 34 tons of gold in ancient times and was the biblical Ophir."


title: Ophir

text: The 10th-century lexicographer, David ben Abraham al-Fasi, identified Ophir with Serendip, the old Persian name for Sri Lanka (aka Ceylon). Moreover, as mentioned above, "A Dictionary of the Bible" by Sir William Smith notes the Hebrew word for parrot "Thukki", derived from the Classical Tamil for peacock "Thogkai" or Sinhalese "tokei". Both Sinhalese and Tamil are native to Sri Lanka.


title: Ophir

text: "A Dictionary of the Bible" by Sir William Smith, published in 1863, notes the Hebrew word for parrot "Thukki", derived from the Classical Tamil for peacock "Thogkai" and Sinhalese "tokei", joins other Classical Tamil words for ivory, cotton-cloth and apes preserved in the Hebrew Bible. This theory of Ophir's location in Tamilakam is further supported by other historians. The most likely location on the coast of Kerala conjectured to be Ophir is Poovar in Thiruvananthapuram District (though some Indian scholars also suggest Beypore as a possible location).


title: Ophir

text: Earlier in the 19th century, Max Müller and other scholars identified Ophir with Abhira, near the Indus River in modern-day state of Gujarat, India. According to Benjamin Walker Ophir is said to have been a town of the Abhira tribe.


title: Ophir

text: In Jewish tradition, Ophir is often associated with a place in the Indian subcontinent, named for one of the sons of Joktan. Ibn Sa'd says in his "Kitab at-Tabaqat al-Kabir" that the Indians, the Sindhis and the Bindis are the descendants of Yufir (Ophir).


title: Ophir

text: In Tomo III (1519-1522), pages 112-138, of the book "Colección general de documentos relativos a las Islas Filipinas existentes en el Archivo de Indias de Sevilla", found in the General Archive of the Indies in Spain, Document No. 98 describes how to locate the land of Ophir. The navigational guide started from the Cape of Good Hope in Africa to India, to Burma, to Sumatra, to the Maluku Islands, to Borneo, to Sulu, to China, then finally Ophir, which is said to be the Philippines.


title: Ophir

text: Biblical scholars, archaeologists and others have tried to determine the exact location of Ophir. Vasco da Gama's companion Tomé Lopes reasoned that Ophir would have been the ancient name for Great Zimbabwe in Zimbabwe, the main center of southern African trade in gold in the Renaissance period — though the ruins at Great Zimbabwe are now dated to the medieval era, long after Solomon is said to have lived. The identification of Ophir with Sofala in Mozambique was mentioned by Milton in "Paradise Lost" (11:399-401), among many other works of literature and science.


title: Ophir

text: Another, more serious, possibility is the African shore of the Red Sea, with the name perhaps being derived from the Afar people living in the Danakil desert (Ethiopia, Eritrea) between Adulis and Djibouti.


title: Ophir

text: Afri was a Latin name used to refer to the Carthaginians, who dwelt in North Africa, in modern-day Tunisia. This name, that later gave the rich Roman province of Africa and the subsequent medieval Ifriqiya, from which the name of the continent Africa is ultimately derived, seems to have referred to a native Libyan tribe originally, however, see Terence for discussion. The name is usually connected with Phoenician "afar", "dust", but a 1981 hypothesis has asserted that it stems from the Berber word "ifri" (plural "ifran") meaning "cave", in reference to cave dwellers. This is proposed to be the origin of "Ophir" as well.


title: Ophir

text: In a letter written in May 1500, Peter Martyr claimed that Christopher Columbus identified Hispaniola with Ophir.


title: Ophir

text: The theologian Benito Arias Montano (1571) proposed finding Ophir in the name of Peru, reasoning that the native Peruvians were thus descendants of Ophir and Shem.


title: Ophir

text: The California Gold Rush boomtown, Ophir, was renamed after "the biblical source of Solomon's treasure."


title: Ophir

text: In 1568, Alvaro Mendaña became the first European to discover the Solomon Islands, and named them as such because he believed them to be Ophir.


title: Ophir

text: For many references and a comprehensive outline of the products exported from Muziris, Ariake &c. cf. George Menachery ed. The St. Thomas Christian Encyclopaedia of India, 1973, 1982, 2009.


title: The Good Cop (American TV series)

text: The Good Cop is an American streaming television comedy-drama murder-mystery created by Andy Breckman. The ten-episode series premiered on Netflix on September 21, 2018. On November 13, 2018, Netflix canceled the series after one season.


title: The Good Cop (American TV series)

text: It is based on an Israeli show of the same name created by Erez and Tomer Aviram and produced by Yoav Gross.


title: The Good Cop (American TV series)

text: Netflix announced the new series in June 2017. The show stars Tony Danza as "a disgraced, former NYPD officer who never followed the rules", and Josh Groban as his son, Tony Jr., "an earnest, obsessively honest NYPD detective who makes a point of always following the rules".


title: The Good Cop (American TV series)

text: The show was created and is written by Andy Breckman, who created and wrote the Emmy Award-winning USA Network series "Monk".


title: The Good Cop (American TV series)

text: The main characters are father and son policemen, Tony Caruso Sr. and Jr., who live together. Tony Sr. (Danza) was expelled from law enforcement and arrested for chronic violations of departmental policy, while his son, Tony Jr. (Groban) scrupulously obeys departmental procedures. During one scene in episode 1, two of Tony Jr.'s colleagues reveal that others in the department refer to him sarcastically as the "Choirboy" and "Nancy Drew." In the series, according to Netflix, "This 'odd couple' become unofficial partners as Tony Sr. offers his overly-cautious son blunt, street-wise advice on everything from handling suspects to handling women."


title: The Good Cop (American TV series)

text: Danza, a native New Yorker, anticipated drawing "on his real-life connection to the NYPD", as a member of the board of directors of the city's Police Athletic League, to develop his character. The first season was filmed in various neighborhoods in Brooklyn.


title: The Good Cop (American TV series)

text: About the series, Breckman said, "Many cop shows feature dark and provocative material: psycho-sexual killers, twisted, grim, flawed detectives. Many address the most controversial issues of the day. I watch a lot of them. God bless 'em all. But the show I want to produce is playful, family-friendly, and a celebration of old-fashioned puzzle-solving."


title: Orogeny

text: Orogeny is a mountain building process. An orogeny is an event that takes place at a convergent plate margin when plate motion compresses the margin. An "orogenic belt" or "orogen" develops as the compressed plate crumples and is uplifted to form one or more mountain ranges. This involves a series of geological processes collectively called orogenesis. These include both structural deformation of existing continental crust and the creation of new continental crust through volcanism. Magma rising in the orogen carries less dense material upwards while leaving more dense material behind, resulting in compositional differentiation of Earth's lithosphere (crust and uppermost mantle). A synorogenic process or event is one that occurs during an orogeny.


title: Orogeny

text: The word "orogeny" () comes from Ancient Greek (, , + , , ). Although it was used before him, the term was employed by the American geologist G. K. Gilbert in 1890 to describe the process of mountain-building as distinguished from epeirogeny.


title: Orogeny

text: Orogeny takes place on the convergent margins of continents. The convergence may take the form of subduction (where a continent rides forcefully over an oceanic plate to form a noncollisional orogeny) or continental collision (convergence of two or more continents to form a collisional orogeny).


title: Orogeny

text: Orogeny typically produces "orogenic belts" or "orogens", which are elongated regions of deformation bordering continental cratons (the stable interiors of continents). Young orogenic belts, in which subduction is still taking place, are characterized by frequent volcanic activity and earthquakes. Older orogenic belts are typically deeply eroded to expose displaced and deformed strata. These are often highly metamorphosed and include vast bodies of intrusive igneous rock called batholiths.


title: Orogeny

text: Subduction zones consume oceanic crust, thicken lithosphere, and produce earthquakes and volcanoes. Not all subduction zones produce orogenic belts; mountain building takes place only when the subduction produces compression in the overriding plate. Whether subduction produces compression depends on such factors as the rate of plate convergence and the degree of coupling between the two plates, while the degree of coupling may in turn rely on such factors as the angle of subduction and rate of sedimentation in the oceanic trench associated with the subduction zone. The Andes Mountains are an example of a noncollisional orogenic belt, and such belts are sometimes called "Andean-type orogens".


title: Orogeny

text: As subduction continues, island arcs, continental fragments, and oceanic material may gradually accrete onto the continental margin. This is one of the main mechanisms by which continents have grown. An orogen built of crustal fragments ("terranes") accreted over a long period of time, without any indication of a major continent-continent collision, is called an "accretionary orogen." The North American Cordillera and the Lachlan Orogen of southeast Australia are examples of accretionary orogens.


title: Orogeny

text: The orogeny may culminate with continental crust from the opposite side of the subducting oceanic plate arriving at the subduction zone. This ends subduction and transforms the accretional orogen into a Himalayan-type collisional orogen. The collisional orogeny may produce extremely high mountains, as has been taking place in the Himalayas for the last 65 million years.


title: Orogeny

text: The processes of orogeny can take tens of millions of years and build mountains from what were once sedimentary basins. Activity along an orogenic belt can be extremely long-lived. For example, much of the basement underlying the United States belongs to the Transcontinental Proterozoic Provinces, which accreted to Laurentia (the ancient heart of North America) over the course of 200 million years in the Paleoproterozoic. The Yavapai and Mazatzal orogenies were peaks of orogenic activity during this time. These were part of an extended period of orogenic activity that included the Picuris orogeny and culminated in the Grenville orogeny, lasting at least 600 million years. A similar sequence of orogenies has taken place on the west coast of North America, beginning in the late Devonian (about 380 million years ago) with the Antler orogeny and continuing with the Sonoma orogeny and Sevier orogeny and culminating with the Laramide orogeny. The Laramide orogeny alone lasted 40 million years, from 75 million to 35 million years ago.


title: Orogeny

text: but they may be broadly divided into collisional orogens and noncollisional orogens (Andean-type orogens). Collisional orogens can be further divided by whether the collision is with a second continent or a continental fragment or island arc. Repeated collisions of the later type, with no evidence of collision with a major continent or closure of an ocean basin, result in an accretionary orogen. Examples of orogens arising from collision of an island arc with a continent include Taiwan and the collision of Australia with the Banda arc. Orogens arising from continent-continent collisions can be divided into those involving ocean closure (Himalayan-type orogens) and those involving glancing collisions with no ocean basin closure (as is taking place today in the Southern Alps of New Zealand).


title: Orogeny

text: Orogens have a characteristic structure, though this shows considerable variation. A "foreland basin" forms ahead of the orogen due mainly to loading and resulting flexure of the lithosphere by the developing mountain belt. A typical foreland basin is subdivided into a wedge-top basin above the active orogenic wedge, the foredeep immediately beyond the active front, a forebulge high of flexural origin and a back-bulge area beyond, although not all of these are present in all foreland-basin systems. The basin migrates with the orogenic front and early deposited foreland basin sediments become progressively involved in folding and thrusting. Sediments deposited in the foreland basin are mainly derived from the erosion of the actively uplifting rocks of the mountain range, although some sediments derive from the foreland. The fill of many such basins shows a change in time from deepwater marine ("flysch"-style) through shallow water to continental ("molasse"-style) sediments.


title: Orogeny

text: While active orogens are found on the margins of present-day continents, older inactive orogenies, such as the Algoman, Penokean and Antler, are represented by deformed and metamorphosed rocks with sedimentary basins further inland.


title: Orogeny

text: Long before the acceptance of plate tectonics, geologists had found evidence within many orogens of repeated cycles of deposition, deformation, crustal thickening and mountain building, and crustal thinning to form new depositional basins. These were named "orogenic cycles", and various theories were proposed to explain them. Canadian geologist Tuzo Wilson first put forward a plate tectonic interpretation of orogenic cycles, now known as Wilson cycles. Wilson proposed that orogenic cycles represented the periodic opening and closing of an ocean basin, with each stage of the process leaving its characteristic record on the rocks of the orogen.


title: Orogeny

text: The Wilson cycle begins when previously stable continental crust comes under tension from a shift in mantle convection. Continental rifting takes place, which thins the crust and creates basins in which sediments accumulate. As the basins deepen, the ocean invades the rift zone, and as the continental crust rifts completely apart, shallow marine sedimentation gives way to deep marine sedimentation on the thinned marginal crust of the two continents.


title: Orogeny

text: As the two continents rift apart, seafloor spreading commenced along the axis of a new ocean basin. Deep marine sediments continue to accumulate along the thinned continental margins, which are now passive margins.


title: Orogeny

text: At some point, subduction is initiated along one or both of the continental margins of the ocean basin, producing a volcanic arc and possibly an Andean-type orogen along that continental margin. This produces deformation of the continental margins and possibly crustal thickening and mountain building.


title: Orogeny

text: Mountain formation in orogens is largely a result of crustal thickening. The compressive forces produced by plate convergence result in pervasive deformation of the crust of the continental margin (thrust tectonics). This takes the form of folding of the ductile deeper crust and thrust faulting in the upper brittle crust.


title: Orogeny

text: Crustal thickening raises mountains through the principle of isostasy. Isostacy is the balance of the downward gravitational force upon an upthrust mountain range (composed of light, continental crust material) and the buoyant upward forces exerted by the dense underlying mantle.


title: Orogeny

text: Portions of orogens can also experience uplift as a result of delamination of the orogenic lithosphere, in which an unstable portion of cold lithospheric root drips down into the asthenospheric mantle, decreasing the density of the lithosphere and causing buoyant uplift. An example is the Sierra Nevada in California. This range of fault-block mountains experienced renewed uplift and abundant magmatism after a delamination of the orogenic root beneath them.


title: Orogeny

text: Mount Rundle on the Trans-Canada Highway between Banff and Canmore provides a classic example of a mountain cut in dipping-layered rocks. Millions of years ago a collision caused an orogeny, forcing horizontal layers of an ancient ocean crust to be thrust up at an angle of 50–60°. That left Rundle with one sweeping, tree-lined smooth face, and one sharp, steep face where the edge of the uplifted layers are exposed.


title: Orogeny

text: Although mountain building mostly takes place in orogens, a number of secondary mechanisms are capable of producing substantial mountain ranges. Areas that are rifting apart, such as mid-ocean ridges and the East African Rift, have mountains due to thermal buoyancy related to the hot mantle underneath them; this thermal buoyancy is known as dynamic topography. In strike-slip orogens, such as the San Andreas Fault, restraining bends result in regions of localized crustal shortening and mountain building without a plate-margin-wide orogeny. Hotspot volcanism results in the formation of isolated mountains and mountain chains that look as if they are not necessarily on present tectonic-plate boundaries, but they are essentially the product of plate tectonism. Likewise, uplift and erosion related to epeirogenesis (large-scale vertical motions of portions of continents without much associated folding, metamorphism, or deformation) can create local topographic highs.


title: Orogeny

text: Eventually, seafloor spreading in the ocean basin comes to a halt, and continued subduction begins to close the ocean basin.


title: Orogeny

text: The closure of the ocean basin ends with a continental collision and the associated Himalayan-type orogen.


title: Orogeny

text: Erosion represents the final phase of the orogenic cycle. Erosion of overlying strata in orogenic belts, and isostatic adjustment to the removal of this overlying mass of rock, can bring deeply buried strata to the surface. The erosional process is called "unroofing". Erosion inevitably removes much of the mountains, exposing the core or "mountain roots" (metamorphic rocks brought to the surface from a depth of several kilometres). Isostatic movements may help such unroofing by balancing out the buoyancy of the evolving orogen. Scholars debate about the extent to which erosion modifies the patterns of tectonic deformation (see erosion and tectonics). Thus, the final form of the majority of old orogenic belts is a long arcuate strip of crystalline metamorphic rocks sequentially below younger sediments which are thrust atop them and which dip away from the orogenic core.


title: Orogeny

text: An orogen may be almost completely eroded away, and only recognizable by studying (old) rocks that bear traces of orogenesis. Orogens are usually long, thin, arcuate tracts of rock that have a pronounced linear structure resulting in terranes or blocks of deformed rocks, separated generally by suture zones or dipping thrust faults. These thrust faults carry relatively thin slices of rock (which are called nappes or thrust sheets, and differ from tectonic plates) from the core of the shortening orogen out toward the margins, and are intimately associated with folds and the development of metamorphism.


title: Orogeny

text: Before the development of geologic concepts during the 19th century, the presence of marine fossils in mountains was explained in Christian contexts as a result of the Biblical Deluge. This was an extension of Neoplatonic thought, which influenced early Christian writers.


title: Orogeny

text: The 13th-century Dominican scholar Albert the Great posited that, as erosion was known to occur, there must be some process whereby new mountains and other land-forms were thrust up, or else there would eventually be no land; he suggested that marine fossils in mountainsides must once have been at the sea-floor. Orogeny was used by Amanz Gressly (1840) and Jules Thurmann (1854) as "orogenic" in terms of the creation of mountain elevations, as the term "mountain building" was still used to describe the processes. Elie de Beaumont (1852) used the evocative "Jaws of a Vise" theory to explain orogeny, but was more concerned with the height rather than the implicit structures created by and contained in orogenic belts. His theory essentially held that mountains were created by the squeezing of certain rocks. Eduard Suess (1875) recognised the importance of horizontal movement of rocks. The concept of a "precursor geosyncline" or initial downward warping of the solid earth (Hall, 1859) prompted James Dwight Dana (1873) to include the concept of "compression" in the theories surrounding mountain-building. With hindsight, we can discount Dana's conjecture that this contraction was due to the cooling of the Earth (aka the cooling Earth theory). The cooling Earth theory was the chief paradigm for most geologists until the 1960s. It was, in the context of orogeny, fiercely contested by proponents of vertical movements in the crust, or convection within the asthenosphere or mantle.


title: Orogeny

text: Gustav Steinmann (1906) recognised different classes of orogenic belts, including the "Alpine type orogenic belt", typified by a flysch and molasse geometry to the sediments; ophiolite sequences, tholeiitic basalts, and a nappe style fold structure.