Portugal is a coastal nation in western Europe, located at the western end of the Iberian Peninsula, bordering Spain (on its northern and eastern frontiers: a total of 1,215 kilometres (755 mi)). The Portuguese territory also includes a series of archipelagos in the Atlantic Ocean (the Azores and Madeira), which are strategic islands along the North Atlantic. The extreme south is not too far from the Strait of Gibraltar, leading to the Mediterranean Sea. In total, the country occupies an area of 92,090 square kilometres (35,560 sq mi) of which 91,470 square kilometres (35,320 sq mi) is land and 620 square kilometres (240 sq mi) water.[1]
Despite these definitions, the Portugal-Spain border remains an unresolved territorial dispute between the two countries. Portugal does not recognise the border between Caia and Ribeira de Cuncos River deltas, since the beginning of the 1801 occupation of Olivenza by Spain. This territory, though under de facto Spanish occupation, remains a de jure part of Portugal, consequently no border is henceforth recognised in this area.[2]
Physical
Portugal is located on the western coast of the Iberian Peninsula and plateau, that divides the inland Mediterranean Sea from the Atlantic Ocean. It is located on the Atlantic coast of this plateau and crossed by several rivers which have their origin in Spain. Most of these rivers flow from east to west disgorging in the Atlantic; from north to south, the primary rivers are the Minho, Douro, Mondego, Tagus and the Guadiana.[3]
Coastline
The Portuguese continental shelf has an area of 28,000 square kilometres (11,000 sq mi), although its width is variable from 150 kilometres (93 mi) in the north to 25 kilometres (16 mi) in the south.[3] Its strong relief is marked by deep submarine canyons and the continuation of the main rivers. The Estremadura Spur separates the Iberian Abyssal and Tagus Abyssal Plains, while the continental slope is flanked by sea-mounts and abuts against the prominent Gorringe Bank in the south.[3] Currently, the Portuguese government claims jurisdiction to a sea depth of 200 metres (660 ft), or to the depth of exploitation.
The Portuguese coast is extensive; in addition to approximately 943 kilometres (586 mi) along the coast of continental Portugal, the archipelagos of the Azores (667 km) and Madeira (250 km) are primarily surrounded by rough cliff coastlines. Most of these landscapes alternate between rough cliffs and fine sand beaches; the region of the Algarve is recognized for its sandy beaches popular with tourists, while at the same time its coastline around Cape St. Vincent is well known for steep and forbidding cliffs. An interesting feature of the Portuguese coast is the Ria Formosa with some sandy islands and a mild and pleasant climate characterized by warm, but not very hot, summers and generally mild winters.
In contrast, the Ria de Aveiro coast (near Aveiro, referred to as "The Portuguese Venice") is formed by a delta approximately 45 kilometres (28 mi) long with a maximum width of 11 kilometres (6.8 mi), rich in fish and seabirds. Four main channels flow through several islands and islets at the mouth of the Vouga, Antuã, Boco, and Fontão Rivers. Since the 16th century, this formation of narrow headlands formed a lagoon, which allowed the formation and production of salt. It was also recognized by the Romans, whose forces exported its salt—then a precious resource—to Rome.
The Azores are sprinkled with both black-sand and boulder-lined beaches; only as a rare exception are there white-sand beaches (such as on the island of Santa Maria in Almagreira). The island of Porto Santo has one of the few extensive dune beaches in Portugal, located in the archipelago of Madeira.
Tidal gauges along the Portuguese coast have identified a 1–1.5 millimetres (0.039–0.059 in) rise in sea levels, causing large estuaries and inland deltas in some major rivers to overflow.[3]
As a result of its maritime possessions and long coastline, Portugal has an Exclusive Economic Zone of 1,727,408 km2 (666,956 sq mi). This is the third largest EEZ of all countries in the European Union and the 20th in the world. This sea-zone, over which Portugal exercises special territorial rights over the economic exploration and use of marine resources, encircles an area of 1,727,408 square kilometres (666,956 sq mi) (divided as: Continental Portugal 327,667 km2, Azores Islands 953,633 km2, Madeira Islands 446,108 km2).
The Portuguese territory came into existence during the history of Gondwana and became aligned with European landforms after the super-continent Pangea began its slow separation into several smaller plates. The Iberian plate was formed during the Cadomian Orogeny of the late Neoproterozoic (about 650-550 Ma), from the margins of the Gondwana continent. Through collisions and accretion a group of island arcs (that included the Central Iberian Plate, Ossa-Morena Plate, South Portuguese Plate) began to disintegrate from Gondwana (along with other European fragments). These plates never separated substantially from each other since this period.[4] By the Mesozoic, the three "Portuguese plates" were a part of the Northern France Armoric Plate until the Bay of Biscay began to separate. Following the separation of the Iberian Abyssal Plain, Iberia and Europe began to drift progressively from North America, as the Mid-Atlantic fracture zone pulled the three plates away from the larger continent. Eventually, Iberia collided with southern France attaching the region into a peninsula of Europe (during the Cenozoic). Since the late Oligocene, the Iberian plate has been moving as part of the Eurasian plate, with the boundary between Eurasia and Africa situated along the Azores–Gibraltar fracture zone.[5][6][7][8][9][10][11][12][5][13]
The Iberian peninsula, defined by its coastline, is due to a fragment of the Variscan tectonic fracture zone, the Iberian-Hesperian Massif, which occupies the west-central part of the plateau.[3] This formation is crossed by the Central System, along an east-northeast to west-southwest alignment, parallel to the European Baetic Chain (an aspect of the Alpine Chain).[3] The Central Cordillera is itself divided into two blocks, while three main river systems drain the differing geomorphological terrains:[3]
the Northern Meseta (with a mean altitude of 800 metres (2,600 ft)) is drained by the Douro River (running east to west);
the Southern Meseta (within a range of 200 to 900 metres (660 to 2,950 ft) altitude) is drained by the Tagus River (running east to west) from Spain, and the Guadiana River (running north to south), comprising the Lower Tagus and Sado Basins.
To the north the landscape is mountainous in the interior areas with plateaus, cut by four breakings lines that allow the development of more fertile agricultural areas.
The south down as far as the Algarve features mostly rolling plains with a climate somewhat warmer and drier than the cooler and rainier north. Other major rivers include the Douro, the Minho and the Guadiana, similar to the Tagus in that all originate in Spain. Another important river, the Mondego, originates in the Serra da Estrela (the highest mountains in mainland Portugal at 1,993 m). A full list of rivers is available in List of rivers of Portugal.
No large natural lakes exist in Continental Portugal, and the largest inland water surfaces are dam-originated reservoirs, such as the Alqueva Reservoir with 250 square kilometres (97 sq mi), the largest[citation needed] in Europe. However, there are several small freshwater lakes in Portugal, the most notable of which are located in Serra da Estrela, Lake Comprida (Lagoa Comprida) and Lake Escura (Lagoa Escura), which were formed from ancient glaciers. Pateira de Fermentelos is a small natural lake near Aveiro, it is one of the largest natural lakes in the Iberian Peninsula and is rich in wildlife. In the Azores archipelago lakes were formed in the caldera of extinct volcanoes. Lagoa do Fogo and Lagoa das Sete Cidades (two small lakes connected by a narrow way) are the most famous lakes in São Miguel Island.
In addition to continental Europe, Portugal consists of two Autonomous Regions in the Atlantic Ocean, consisting of the archipelagos of Madeira and Azores. Madeira is located on the African Tectonic Plate, and comprises the main island of Madeira, Porto Santo and the smaller Savage Islands. The Azores, which are located between the junction of the African, European and North American Plates, straddle the Mid-Atlantic Ridge. There are nine islands in this archipelago, usually divided into three groups (Western, Central and Eastern) and several smaller Formigas (rock outcroppings) located between São Miguel and Santa Maria Islands. Both island groups are volcanic in nature, with historic volcanology and seismic activity persisting to the present time. In addition, there are several submarine volcanos in the Azores (such as Dom João de Castro Bank), that have erupted historically (such as the Serrata eruption off the coast of Terceira Island). The last major volcanic event occurred in 1957-58 along the western coast of Faial Island, which formed the Capelinhos Volcano. Seismic events are common in the Azores.
The Azores are occasionally subject to very strong earthquakes, as is the continental coast. Wildfires occur mostly in the summer in mainland Portugal and extreme weather in the form of strong winds and floods also occurs mainly in winter. The Azores are occasionally stricken by tropical cyclones such as Hurricane Jeanne (1998) and Hurricane Gordon (2006).
The annual average temperature in mainland Portugal varies from 12–13 °C (53.6–55.4 °F) in the mountainous interior north to 17–19 °C (62.6–66.2 °F) in the south (in general the south is warmer and drier than the north). The Madeira and Azores archipelagos have a narrower temperature range. Extreme temperatures occur in the mountains in the interior North and Centre of the country in winter, where they may fall below −10 °C (14 °F) or in rare occasions below −15 °C (5 °F), particularly in the higher peaks of Serra da Estrela, and in southeastern parts in the summer, sometimes exceeding 45 °C (113 °F). The official absolute extreme temperatures are −16 °C (3.2 °F) in Penhas da Saúde on 4 February 1954 and Miranda do Douro, and 47.4 °C (117.3 °F) in Amareleja in the Alentejo region, on 1 August 2003.[14] There are, however, unofficial records of 50.5 °C (122.9 °F) on 4 August 1881 in Riodades, São João da Pesqueira[15] and 70 °C (158.0 °F) on 6 July 1949 in Figueira da Foz in an apparent heat burst (see the Highest temperature recorded on Earth). Such temperatures are not validated since these were measured in enclosures that were much more susceptible to solar radiation and/or in enclosed gardens which tend to heat up a lot more than in the open where temperatures should be measured. There are also records of −17.5 °C (0.5 °F) from a Polytechnic Institute in Bragança, and below −20 °C (−4.0 °F) in Serra da Estrela, which have no official value since they were not recorded by IPMA. Such values are however perpetuated by weather enthusiasts who are fond of extremes. The annual average rainfall in continental Portugal varies from a bit more than 2,000 mm (78.7 in) in the mountains in the north to less than 500 mm (19.7 in) in southern parts of Alentejo, however in Macaronesia, Pico Island holds the record with over 6,250 mm (246.1 in) and the Savage Islands around 200 mm (7.9 in). Portugal as a whole is amongst the sunniest areas in Europe, with around 2300–3200 hours of sunshine a year, an average of 4-6h in winter and 10-12h in the summer. The sea surface temperature is higher in the south coast where it varies from 15.5–16 °C (59.9–60.8 °F) in January to 21–23 °C (69.8–73.4 °F) in August, occasionally reaching 25 °C (77 °F); on the west coast the sea surface temperature is around 14–16 °C (57.2–60.8 °F) in winter and 18–20 °C (64–68 °F) in the summer.[16]
Climate data for Continental Portugal, 1981-2010 normals (humidity 1971-2000), 2003-present day extremes
Environment - international agreements: party to:
Air Pollution, Biodiversity, Climate Change, Desertification, Endangered Species, Hazardous Wastes, Law of the Sea, Marine Dumping, Marine Life Conservation, Ozone Layer Protection, Ship Pollution, Tropical Timber 83, Tropical Timber 94, Wetlands
signed, but not ratified:
Air Pollution-Persistent Organic Pollutants, Air Pollution-Volatile Organic Compounds, Climate Change-Kyoto Protocol, Environmental Modification, Nuclear Test Ban
Terrain:
Mountainous and hilly north of the Tagus River, rolling plains in south
Elevation extremes: lowest point:
Atlantic Ocean 0 m
highest point:Ponta do Pico (Pico or Pico Alto) on Ilha do Pico in the Azores 2,351 m
^Grimaud, S.; Boillot, G.; Collette, B.J.; Mauffret, A.; Miles, P.R.; Roberts, D.B. (January 1982). "Western extension of the Iberian-European plate boundary during the Early Cenozoic (Pyrenean) convergence: A new model". Marine Geology. 45 (1–2): 63–77. Bibcode:1982MGeol..45...63G. doi:10.1016/0025-3227(82)90180-3.
^Olivet, J.L.; Auzende, J.M.; Beuzart, P. (September 1983). "Western extension of the Iberian-European plate boundary during the Early Cenozoic (Pyrenean) convergence: A new model — Comment". Marine Geology. 53 (3): 237–238. Bibcode:1983MGeol..53..237O. doi:10.1016/0025-3227(83)90078-6.
^Grimaud, S.; Boillot, G.; Collette, B.J.; Mauffret, A.; Miles, P.R.; Roberts, D.B. (September 1983). "Western extension of the Iberian-European plate boundary during the Early Cenozoic (Pyrenean) convergence: A new model — Reply". Marine Geology. 53 (3): 238–239. Bibcode:1983MGeol..53..238G. doi:10.1016/0025-3227(83)90079-8.
Le Pichon, Xavier; Sibuet, Jean-Claude; Francheteau, Jean (March 1977). "The fit of the continents around the North Atlantic Ocean". Tectonophysics. 38 (3–4): 169–209. Bibcode:1977Tectp..38..169L. doi:10.1016/0040-1951(77)90210-4.
Savostin, Léonid A.; Sibuet, Jean-Claude; Zonenshain, Lev P.; Le Pichon, Xavier; Roulet, Marie-José (March 1986). "Kinematic evolution of the Tethys belt from the Atlantic ocean to the pamirs since the Triassic". Tectonophysics. 123 (1–4): 1–35. Bibcode:1986Tectp.123....1S. doi:10.1016/0040-1951(86)90192-7.
Sclater, John G.; Hellinger, Steven; Tapscott, Christopher (September 1977). "The Paleobathymetry of the Atlantic Ocean from the Jurassic to the Present". The Journal of Geology. 85 (5): 509–552. Bibcode:1977JG.....85..509S. doi:10.1086/628336. S2CID129522366.
Seber, Dogan; Barazangi, Muawia; Ibenbrahim, Aomar; Demnati, Ahmed (February 1996). "Geophysical evidence for lithospheric delamination beneath the Alboran Sea and Rif–Betic mountains". Nature. 379 (6568): 785–790. Bibcode:1996Natur.379..785S. doi:10.1038/379785a0. hdl:1813/5287. S2CID4332684.
Srivastava, S. P.; Schouten, H.; Roest, W. R.; Klitgord, K. D.; Kovacs, L. C.; Verhoef, J.; Macnab, R. (April 1990). "Iberian plate kinematics: a jumping plate boundary between Eurasia and Africa". Nature. 344 (6268): 756–759. Bibcode:1990Natur.344..756S. doi:10.1038/344756a0. S2CID4362197.
External links
Visible Earth. NASA-Goddard Space Flight Center. [1]. A collection of satellite images of Portugal and the surrounding region.
Pemilihan umum Bupati Merangin 20132008201825 Maret 2013[1]Kandidat Calon Nalim Syukur Handayani Partai Demokrat PAN PKB Pendamping Salam Fauziah Jailani Suara rakyat 49.519 47.678 22.576 Persentase 25.50% 24.49% 11.62% Calon Al Haris Partai Golkar Pendamping Abdul Khafidh Suara rakyat 71.059 Persentase 36.59% Peta persebaran suara Letak Kabupaten Merangin di Provinsi Jambi Bupati petahanaNalim Demokrat Bupati terpilih Al Haris Golkar Pemilihan umum Bupati Mer...
Jennifer McCreight berpartisipasi dalam percobaan Boobquake Boobquake adalah suatu kampanye yang diselenggarakan pada 26 April 2010 yang diprakarsai oleh Jennifer McCreight, seorang penulis blog yang juga merupakan senior di Universitas Purdue, untuk merespon sebuah berita yang melaporkan Hujjat al-Islam Iran, Kazem Seddiqi menyatakan bahwa mempertontonkan aurat itu dapat menyebabkan gempa bumi. Pada 19 April 2010 diberitakan bahwa Seddiqi mengatakan, Banyak wanita yang berpakaian tidak sopan...
SMA Negeri 18 MedanInformasiAkreditasiB[1]Nomor Statistik Sekolah30.1.07.60.01.002Jurusan atau peminatanIPA dan IPSRentang kelasX IPA, X IPS, XI IPA, XI IPS, XII IPA, XII IPSKurikulumKurikulum 2013AlamatLokasiJl. Wahidin 15A, Medan, Sumatera UtaraMoto SMA Negeri (SMAN) 18 Medan SMANDELAS, merupakan salah satu Sekolah Menengah Atas Negeri yang ada di Provinsi Sumatera Utara, Indonesia. Sama dengan SMA pada umumnya di Indonesia masa pendidikan sekolah di SMAN 18 Medan ditempuh dalam wak...
Daniel CokeDaniel Coke, dengan sepupunya Rev. D'Ewes Coke (berdiri) dan istri sepupunya, dilukis oleh Joseph Wright, 1782Lahir17 Juli 1745Derbyshire?Meninggal6 Desember 1825DerbyPendidikanDerby School, Queen's College, Oxford, dan All Souls College, OxfordPekerjaanpengacara dan anggota parlemenSuami/istritidak adaOrang tuaThomas dan Matilda Coke Daniel Parker Coke (17 Juli 1745 – 6 Desember 1825), adalah seorang pengacara Inggris dan anggota Dewan Rakyat Britania Raya. Kehidu...
Artikel ini mendokumentasikan suatu wabah penyakit terkini. Informasi mengenai hal itu dapat berubah dengan cepat jika informasi lebih lanjut tersedia; laporan berita dan sumber-sumber primer lainnya mungkin tidak bisa diandalkan. Pembaruan terakhir untuk artikel ini mungkin tidak mencerminkan informasi terkini mengenai wabah penyakit ini untuk semua bidang. Artikel utama: Pandemi koronavirus 2019–2020 Pandemi koronavirus di Italia Kasus terkonfirmasi menurut provinsi (per 100rb) Prevalensi...
Pour les articles homonymes, voir Intégrisme. Le libéralisme est un péché, opuscule intégriste de Félix Sardá y Salvany publié en 1884. L’intégrisme (en espagnol : integrismo) est un courant politique espagnol réactionnaire de la fin du XIXe siècle et du début du XXe siècle. Héritiers de mouvements catholiques ultra-conservateurs tels que les néo-catholiques ou le carlisme, les intégristes représentaient l’aile la plus droitière de l’échiquier politiqu...
Harriet Lepel Phipps Harriet Lepel Phipps, VA (1841 – 7 Maret 1922) adalah seorang pelayan kepercayaan dari Ratu Victoria. Harriet adalah putri bungsu dari Sir Charles Beaumont Phipps, seorang abdi dalem dan orang kepercayaan Ratu, yang menjabat sebagai Penjaga Pundi-Pundi Pribadi. Harriet diangkat menjadi Dayang Kehormatan atas Perintah Ratu pada 3 Maret 1862 (memberikannya gelar kehormatan dari seorang putri baron),[1] dan kemudian menjabat sebagai Woman of the Bedchamber dari 188...
Wife of the president of Palau First Lady of PalauFlag of PalauIncumbentValerie Whippssince 21 January 2021Inaugural holderRegina RemeliikFormation2 March 1981 First Lady of Palau is the official title attributed to the wife of the president of Palau. The country's current first lady is Valerie Whipps, wife of President Surangel Whipps Jr., who had held the position since 21 January 2021. First ladies of Palau Name Portrait Term Began Term Ended President Notes Regina Namiko Remeliik[...
Yankee SquadronThe No. 56 Chato flown by F. G. TinkerActive1936–1937Country United StatesAllegiance SpainBranchSpanish Republican Air ForceTypeAir Force SquadronSize6Military unit Spanish Civil War Medal awarded to the International Brigades The Yankee Squadron was a group of mercenary American military aviators who flew for the Spanish Republican Air Force during the Spanish Civil War.[1][2][3] History In November 1936, representatives of the Second Spanish Republi...
Министерство природных ресурсов и экологии Российской Федерациисокращённо: Минприроды России Общая информация Страна Россия Юрисдикция Россия Дата создания 12 мая 2008 Предшественники Министерство природных ресурсов Российской Федерации (1996—1998)Министерство охраны...
Earldom in the Peerage of Great Britain Earldom of Lonsdale 2nd Creation Arms: Or, six Annulets Sable, three, two and one. Crest: A Dragon passant Argent.. Supporters: On either side a Horse Argent, gored with a Wreath of Laurel Vert.Creation date7 April 1807CreationSecondCreated byKing George IIIPeeragePeerage of the United KingdomFirst holderWilliam Lowther, 1st Earl of LonsdalePresent holderWilliam James Lowther, 9th Earl of LonsdaleSubsidiary titlesViscount Lowther Baron Lowther Baronet '...
Historic house in Massachusetts, United States United States historic placeFairbanks HouseU.S. National Register of Historic PlacesU.S. National Historic Landmark Fairbanks House in 2013Show map of MassachusettsShow map of the United StatesInteractive map showing the location of Fairbanks HouseLocation511 East Street, Dedham, MassachusettsCoordinates42°14′36″N 71°10′04″W / 42.24333°N 71.16778°W / 42.24333; -71.16778Builtca. 1637[1]NRHP referenc...
Boris BeckerKebangsaanJerman Barat (1983–1990) Jerman (sejak 1990)Tempat tinggalSchwyz, SwissTinggi190 m (623 ft 4+1⁄2 in)Berat85 kg (187 pon; 13,4 st)Memulai pro1984Pensiun30 Juni 1999Tipe pemainTangan kananTotal hadiah25.080.956 Dolar AS Pendapatan terbanyak ke-5 sepanjang masa Int. Tennis HoF2003 (member page)TunggalRekor (M–K)713–214 (76.91%)Gelar49Peringkat tertinggiNo. 1 (28 Januari 1991)Hasil terbaik di Grand Slam (tunggal)Australia TerbukaJuar...
Sukunda oil lamp made of silver Serving rice wine during Sagan, note egg and smoked fish in left hand Sagun (Nepali: सगन) is a Nepalese ceremony which involves ritualized presentation of auspicious food to a person to invoke good fortune and show respect. It is a highly revered ceremony in Newar society of the Kathmandu Valley. The food items served are boiled egg, smoked fish, meat, lentil cake and rice wine which represent Tantric concepts.[1] The Sagan is presented during lif...
Questa voce o sezione sull'argomento religiosi tibetani non cita le fonti necessarie o quelle presenti sono insufficienti. Puoi migliorare questa voce aggiungendo citazioni da fonti attendibili secondo le linee guida sull'uso delle fonti. Tenzin Gyatsoབསྟན་འཛིན་རྒྱ་མཚོ།XIV Dalai Lama del TibetIn caricadal 22 febbraio 1940 Incoronazione17 novembre 1950 PredecessoreThubten Gyatso Nome completoJetsun Jamphel Ngawang Lobsang Yeshe Tenzin Gyatso Nasc...
Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης Universidad Aristóteles de Tesalónica Sigla AUTHLema MOYΣAIΣ XAPIΣI ΘYE«Sacrificio con la gracia de las Musas»Fundación 1925LocalizaciónDirección Tesalónica, Grecia GreciaCoordenadas 40°37′48″N 22°57′29″E / 40.63, 22.958055555556AdministraciónRector Ioannis MylopoulosAfiliaciones EUA, Grupo Coimbra, TIME, Red de Utrecht, Mediterra, IAUAdministrativos 961AcademiaProfesores 2.2...
Rolando SchiaviSchiavi nel 2014Nazionalità Argentina Altezza190 cm Peso83 kg Calcio RuoloDifensore Termine carriera29 luglio 2014 - giocatore CarrieraGiovanili 19??-1993 Atlético Argentino Squadre di club1 1993-1995 Atlético Argentino37 (0)1996-2001 Argentinos Juniors150 (10)2001-2005 Boca Juniors112 (12)2006 Hércules34 (1)2007 Grêmio11 (0)2007-2011 Newell's Old Boys120 (18)2009→ Estudiantes (LP)4 (0)2011-2012 Boca Juniors67 (5)2013-20...
У Вікіпедії є статті про інші значення цього терміна: Архітектура (значення). Брунеллескі, своїм Флорентійським собором на початку 15-го століття не тільки перетворив будівництво та місто, але й роль та статус архітектора.[1][2] Архітекту́ра (грец. αρχιτεκτονικη...
Critical experiment This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.Find sources: Experimentum crucis – news · newspapers · books · scholar · JSTOR (August 2017) (Learn how and when to remove this message) In science, an experimentum crucis (English: crucial experiment or critical experiment) is an experiment capable of d...
Knot invariant In mathematics, the Alexander polynomial is a knot invariant which assigns a polynomial with integer coefficients to each knot type. James Waddell Alexander II discovered this, the first knot polynomial, in 1923. In 1969, John Conway showed a version of this polynomial, now called the Alexander–Conway polynomial, could be computed using a skein relation, although its significance was not realized until the discovery of the Jones polynomial in 1984. Soon after Conway's reworki...