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39-611: The time of formation of the faults related to the Saguenay Graben is still under debate because it is difficult to accurately measure the age of faulting. Evidence suggests it was either the opening of the Iapetus Ocean (600–400 Ma), or the opening of the Atlantic Ocean (195–170 Ma) that caused the faulting. During the opening of one of these oceans, fragmentation of the landmass occurred creating two fault planes, one to

78-611: A precursor before the time of Pangaea . Wilson also noticed that the Atlantic had opened at roughly the same place where its precursor ocean had closed. This led him to his Wilson cycle hypothesis. In many spots in Scandinavia basaltic dikes are found with ages between 670 and 650 million years. These are interpreted as evidence that by that time, rifting had started that would form the Iapetus Ocean. In Newfoundland and Labrador ,

117-510: Is believed to have opened around 700 Ma as Laurentia drifted away from Amazonia, with the Iapetus Ocean being separated from the Puncoviscana Ocean by the ribbon-shaped Arequipa-Antofalla terrane . However, the formation of both oceans seems unrelated. Southwest of the Iapetus, a volcanic island arc evolved from the early Cambrian (540 million years ago) onward. This volcanic arc

156-501: Is inscribed on two 5th-century BC Etruscan bronze items: a mirror from Vulci and a ring from an unknown site. Both objects depict the encounter with Atlas of Hercle —the Etruscan Heracles —identified by the inscription; they represent rare instances where a figure from Greek mythology was imported into Etruscan mythology , but the name was not. The Etruscan name Aril is etymologically independent. Sources describe Atlas as

195-743: The Hesperides , the Hyades , the Pleiades , and the nymph Calypso who lived on the island Ogygia . The term " atlas " has been used to describe a collection of maps since the 16th century when Flemish geographer Gerardus Mercator published his work in honor of the mythological Titan. The " Atlantic Ocean " is derived from "Sea of Atlas". The name of Atlantis mentioned in Plato's Timaeus ' dialogue derives from "Atlantis nesos" ( Ancient Greek : Ἀτλαντὶς νῆσος ), literally meaning "Atlas's Island". The etymology of

234-663: The Long Range dikes are also thought to have formed during the formation of the Iapetus Ocean. It has been proposed that both the Fen Complex in Norway and the Alnö Complex in Sweden formed as consequence to mild extensional tectonics in the ancient continent of Baltica that followed the opening of the Iapetus Ocean. The eastern Iapetus Ocean is believed to have opened around 590 Ma with

273-465: The Paleozoic that are found only in the graben due to its faulting. 48°30′N 71°20′W  /  48.500°N 71.333°W  / 48.500; -71.333 Iapetus Ocean The Iapetus Ocean ( / aɪ ˈ æ p ɪ t ə s / ; eye- AP -ih-təs ) existed in the late Neoproterozoic and early Paleozoic eras of the geologic timescale (between 600 and 400 million years ago). It

312-468: The Pleistocene . The graben was located relatively parallel to the ice sheet movement and therefore caused it to become a preferred travel pathway for ice. The glaciers cut into the graben and widened it in some places as well as making it considerably deeper in others. After the retreat of the final ice sheet, there was considerable isostatic rebound . The total amount of rebound varied from 140 m on

351-523: The continental shelves of Baltica and Laurentia are still very different in the Ordovician, but Silurian faunas show progressive mixing of species from both sides, because the continents moved closer together. In the west, the Iapetus Ocean closed with the Taconic orogeny (480-430 million years ago), when the volcanic island arc collided with Laurentia. Some authors consider the oceanic basin south of

390-614: The golden apples , and Gorgons both of which were said to live beyond Ocean in the extreme west of the world since Hesiod 's Theogony . Diodorus and Palaephatus mention that the Gorgons lived in the Gorgades, islands in the Aethiopian Sea . The main island was called Cerna, and modern-day arguments have been advanced that these islands may correspond to Cape Verde due to Phoenician exploration. The Northwest Africa region emerged as

429-672: The Graben is between 200 and 800 m in altitude. The Saguenay River as well as the Lac Saint-Jean are both contained within the Saguenay Graben. The Saguenay Graben is in the Grenville Province (but was created long after the Grenville Orogeny ). The Saguenay Graben is characterized primarily by the rock types: gneiss , anorthosite and granite that are Proterozoic in age. There are two outliers of limestone and shale of

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468-514: The Iapetus Ocean was positioned between continental masses that would at a much later time roughly form the opposite shores of the Atlantic Ocean , it can be seen as a sort of precursor of the Atlantic, and the process by which it opened shares many similarities with that of the Atlantic's initial opening in the Jurassic . The Iapetus Ocean was therefore named for the titan Iapetus , who in Greek mythology

507-595: The canonical home of the King via separate sources. In particular, according to Ovid, after Perseus turns Atlas into a mountain range, he flies over Aethiopia , the blood of Medusa's head giving rise to Libyan snakes. By the time of the Roman Empire , the habit of associating Atlas's home to a chain of mountains, the Atlas Mountains , which were near Mauretania and Numidia , was firmly entrenched. The identifying name Aril

546-497: The dragon Ladon . Heracles went to Atlas and offered to hold up the heavens while Atlas got the apples from his daughters. Upon his return with the apples, however, Atlas attempted to trick Heracles into carrying the sky permanently by offering to deliver the apples himself, as anyone who purposely took the burden must carry it forever, or until someone else took it away. Heracles, suspecting Atlas did not intend to return, pretended to agree to Atlas's offer, asking only that Atlas take

585-621: The eastern parts had closed too: the Tornquist Sea between Avalonia and Baltica already during the late Ordovician, the main branch between Baltica-Avalonia and Laurentia during the Grampian and Scandian phases of the Caledonian orogeny (440–420 million years ago). At the end of the Silurian period (c. 420 million years ago) the Iapetus Ocean had completely disappeared and the combined mass of

624-656: The emplacement of the Central Iapetus Magmatic Province between Laurentia and Baltica. The southern Iapetus Ocean opened between Laurentia and southwestern Gondwana (now South America) about 550 Ma, close to the end of the Ediacaran period. At the time it did so the Adamastor Ocean further east closed . The opening of the Iapetus Ocean probably postdates the opening of the Puncoviscana Ocean , which

663-454: The father, by different goddesses, of numerous children, mostly daughters. Some of these are assigned conflicting or overlapping identities or parentage in different sources. Hyginus , in his Fabulae , adds an older Atlas who is the son of Aether and Gaia . Atlas' best-known cultural association is in cartography . The first publisher to associate the Titan Atlas with a group of maps

702-474: The first king of Atlantis was also named Atlas , but that Atlas was a son of Poseidon and the mortal woman Cleito. The works of Eusebius and Diodorus also give an Atlantean account of Atlas. In these accounts, Atlas' father was Uranus and his mother was Gaia . His grandfather was Elium "King of Phoenicia " who lived in Byblos with his wife Beruth . Atlas was raised by his sister, Basilia . Atlas

741-491: The greatest Greek heroes : Heracles ( Hercules in Roman mythology ) and Perseus . According to the ancient Greek poet Hesiod , Atlas stood at the ends of the earth in the extreme west . Later, he became commonly identified with the Atlas Mountains in northwest Africa and was said to be the first King of Mauretania (modern-day Morocco and west Algeria , not to be confused with the modern-day country of Mauritania ). Atlas

780-529: The island arc also a part of the Iapetus, this branch closed during the later Acadian orogeny , when Avalonia collided with Laurentia. It has been suggested that the southern Iapetus Ocean closed during a continental collision between Laurentia and Western Gondwana (South America). If factual the Taconic orogen would be the northward continuation of the Famatinian orogen exposed in Argentina. Meanwhile,

819-471: The myth of Heracles. In this account Atlas is not a shepherd, but a king. According to Ovid, Perseus arrives in Atlas's Kingdom and asks for shelter, declaring he is a son of Zeus. Atlas, fearful of a prophecy that warned of a son of Zeus stealing his golden apples from his orchard, refuses Perseus hospitality. In this account, Atlas is turned not just into stone by Perseus, but an entire mountain range: Atlas's head

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858-471: The name Atlas is uncertain. Virgil took pleasure in translating etymologies of Greek names by combining them with adjectives that explained them: for Atlas his adjective is durus , "hard, enduring", which suggested to George Doig that Virgil was aware of the Greek τλῆναι "to endure"; Doig offers the further possibility that Virgil was aware of Strabo 's remark that the native North African name for this mountain

897-440: The north and one to the south. The resulting bedrock between dropped down along the normal faults, creating the Saguenay Graben. The extent of these faults are only known at the surface and therefore their extension and shape at depth is unknown. The faults associated with the Saguenay Graben have been the source for earthquakes , including the 1988 Saguenay earthquake . The area was covered by ice sheets several times throughout

936-558: The north side and 120 m on the south side. The lowlands within the graben have an altitude of between 100 and 200 m. To the east there is the Kenogami threshold which is characterized by having an altitude of 200 to 260 m. This threshold splits the graben into two physiographic regions; the Lac Saint-Jean region to the west and the Saguenay region to the east. The plateau around

975-574: The peak, his shoulders ridges and his hair woods. The prophecy did not relate to Perseus stealing the golden apples but to Heracles , another son of Zeus, and Perseus's great-grandson. One of the Twelve Labours of the hero Heracles was to fetch some of the golden apples that grow in Hera 's garden, tended by Atlas's reputed daughters, the Hesperides (which were also called the Atlantides), and guarded by

1014-546: The sky again for a few minutes so Heracles could rearrange his cloak as padding on his shoulders. When Atlas set down the apples and took the heavens upon his shoulders again, Heracles took the apples and ran away. In some versions, Heracles instead built the two great Pillars of Hercules to hold the sky away from the earth, liberating Atlas much as he liberated Prometheus . Besides the Titan, there are other mythological characters who were also called Atlas: According to Plato ,

1053-430: The solidity of the marble globe borne by the renowned Farnese Atlas may have aided the conflation, reinforced in the 16th century by the developing usage of atlas to describe a corpus of terrestrial maps . The Greek poet Polyidus c.  398 BC tells a tale of Atlas, then a shepherd, encountering Perseus who turned him to stone . Ovid later gives a more detailed account of the incident, combining it with

1092-536: The southern parts of the British Isles and eastern Newfoundland. Geologists of the early 20th century presumed that a large trough, a so-called geosyncline , had existed between Scotland and England in the early Paleozoic, keeping the two sides separated. With the development of plate tectonics in the 1960s, geologists such as Arthur Holmes and John Tuzo Wilson concluded that the Atlantic Ocean must have had

1131-470: The three continents formed the "new" continent of Laurasia , which would itself be the northern component of the singular supercontinent of Pangaea . Atlas (mythology) In Greek mythology , Atlas ( / ˈ æ t l ə s / ; Ancient Greek : Ἄτλας , Átlās ) is a Titan condemned to hold up the heavens or sky for eternity after the Titanomachy . Atlas also plays a role in the myths of two of

1170-453: The western edge of the earth and hold up the sky on his shoulders. Thus, he was Atlas Telamon , "enduring Atlas", and became a doublet of Coeus , the embodiment of the celestial axis around which the heavens revolve. A common misconception today is that Atlas was forced to hold the Earth on his shoulders, but Classical art shows Atlas holding the celestial spheres , not the terrestrial globe ;

1209-441: The word Atlas as a dedication specifically to honor the Titan Atlas, in his capacity as King of Mauretania , a learned philosopher, mathematician, and astronomer. In psychology, Atlas is used metaphorically to describe the personality of someone whose childhood was characterized by excessive responsibilities . Ayn Rand's political dystopian novel Atlas Shrugged (1957) references the popular misconception of Atlas holding up

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1248-673: Was Douris . Since the Atlas Mountains rise in the region inhabited by Berbers , it has been suggested that the name might be taken from one of the Berber languages , specifically from the word ádrār "mountain". Traditionally historical linguists etymologize the Ancient Greek word Ἄτλας ( genitive : Ἄτλαντος) as comprised from copulative α- and the Proto-Indo-European root *telh₂- 'to uphold, support' (whence also τλῆναι), and which

1287-477: Was also a legendary king of Mauretania , the land of the Mauri in antiquity roughly corresponding with modern Morocco and Algeria . In the 16th century, Gerardus Mercator put together the first collection of maps to be called an " Atlas " and devoted his book to the "King of Mauretania". Atlas became associated with Northwest Africa over time. He had been connected with the Hesperides , or "Nymphs", which guarded

1326-524: Was formed above a subduction zone where the oceanic lithosphere of the Iapetus Ocean subducted southward under other oceanic lithosphere . From Cambrian times (about 550 million years ago) the western Iapetus Ocean began to grow progressively narrower due to this subduction. The same happened further north and east, where Avalonia and Baltica began to move towards Laurentia from the Ordovician (488–444 million years ago) onward. Trilobite faunas of

1365-494: Was in the southern hemisphere , between the paleocontinents of Laurentia , Baltica and Avalonia . The ocean disappeared with the Acadian , Caledonian and Taconic orogenies , when these three continents joined to form one big landmass called Euramerica . The "southern" Iapetus Ocean has been proposed to have closed with the Famatinian and Taconic orogenies, meaning a collision between Western Gondwana and Laurentia. Because

1404-603: Was later reshaped to an nt-stem. However, Robert S. P. Beekes argues that it cannot be expected that this ancient Titan carries an Indo-European name, and he suggests instead that the word is of Pre-Greek origin, as such words often end in -ant . Atlas and his brother Menoetius sided with the Titans in their war against the Olympians , the Titanomachy . When the Titans were defeated, many of them (including Menoetius) were confined to Tartarus , but Zeus condemned Atlas to stand at

1443-515: Was said to have been skilled in philosophy , mathematics , and astronomy . In antiquity, he was credited with inventing the first celestial sphere . In some texts, he is even credited with the invention of astronomy itself. Atlas was the son of the Titan Iapetus and the Oceanid Asia or Clymene . He was a brother of Epimetheus and Prometheus . He had many children, mostly daughters,

1482-475: Was the father of Atlas , after whom the Atlantic Ocean was named. At the start of the 20th century, American paleontologist Charles Walcott noticed differences in early Paleozoic benthic trilobites of Laurentia (such as Olenellidae , the so-called "Pacific fauna"), as found in Scotland and western Newfoundland , and those of Baltica (such as Paradoxididae , often called the "Atlantic fauna"), as found in

1521-467: Was the print-seller Antonio Lafreri , who included a depiction of the Titan on the engraved titlepage he applied to his ad hoc assemblages of maps, Tavole Moderne di Geografia de la Maggior parte del Mondo di Diversi Autori (1572). However, Lafreri did not use the word "Atlas" in the title of his work; this was an innovation of Gerardus Mercator , who named his work Atlas Sive Cosmographicae Meditationes de Fabrica Mundi et Fabricati (1585–1595), using

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