Инд. авторы:	Khromykh S.V., Kotler P.D., Izokh A.E., Kruk N.N.
Заглавие:	A review of early permian (300-270 ma) magmatism in eastern kazakhstan and implications for plate tectonics and plume interplay
Библ. ссылка:	Khromykh S.V., Kotler P.D., Izokh A.E., Kruk N.N. A review of early permian (300-270 ma) magmatism in eastern kazakhstan and implications for plate tectonics and plume interplay // Геодинамика и тектонофизика. - 2019. - Vol.10. - Iss. 1. - P.79-99. - EISSN 2078-502X.
Идентиф-ры:	DOI: 10.5800/GT-2019-10-1-0405; РИНЦ: 37314318; SCOPUS: 2-s2.0-85065071050; WoS: 000472643100005;
Реферат:	eng: The history of the Central Asian Orogenic Belt (CAOB) was marked by several major events of magmatism which produced large volumes of volcanic and intrusive (mafic-ultramafic and granitic) rocks within a relatively short time span (30-40 Ma) over a vast area. The magmatic activity postdated the orogenic stages of accretionary-collisional belts in Central Asia and likely resulted from the impact of mantle plumes that formed Large Igneous Provinces (LIPs). The formation of the Tarim-South Mongolia LIP at 300-270 Ma is the best known among the major Permian events of basaltic and granitic magmatism. Early Permian igneous rocks (volcanic, subvolcanic and intrusive suites that vary from ultramafic to felsic compositions) of the same age range (300 to 270 Ma) have been recently found also in Eastern Kazakhstan, within the late Paleozoic Altai collisional system. The compositions and ages of the rocks suggest that the Eastern Kazakhstan magmatism was the northward expansion of the Tarim LIP. The spread of the Tarim LIP was apparently facilitated by lithospheric extension after the Siberia-Kazakhstan collision. The extension led to rheological weakening of the lithosphere whereby deep mantle melts could penetrate to shallower depths. The early Permian history of Eastern Kazakhstan was controlled by the interplay of plate tectonic and plume processes: plate-tectonic accretion and collision formed the structural framework, and the Tarim mantle plume was a heat source maintaining voluminous magma generation. rus: В истории развития крупнейшего Центрально-Азиатского складчатого пояса (ЦАСП) выявлены несколько периодов крупномасштабной эндогенной активности, характеризующихся проявлениями значительных объемов вулканических и интрузивных (как базитовых, так и гранитоидных) пород на обширных территориях в сравнительно короткие временные интервалы (30-40 млн лет). Эти вспышки магматической активности обычно происходят после завершения аккреционно-коллизионных процессов в складчатых системах и рассматриваются как результат воздействия мантийных плюмов на литосферу - крупные изверженные провинции. Одним из ярких примеров является Тарим-Южномонгольская крупная изверженная провинция (300-270 млн лет назад), характеризующаяся широким развитием базитового и гранитоидного магматизма в западной части ЦАСП. Исследования последних лет показали, что в Восточном Казахстане, в пределах Алтайской коллизионной системы герцинид, широко распространены как базитовые, так и гранитоидные комплексы раннепермского возраста (300-270 млн лет). В приведенном кратком обзоре показано, что особенности состава и условия формирования этих магматических ассоциаций позволяют рассматривать их как результат северо-западного распространения влияния Таримской крупной изверженной провинции. Распространение этого термического возмущения в литосфере, по-видимому, стало возможным благодаря пост-орогеническому растяжению после коллизии Сибирского и Казахстанского континентов. Реологическое ослабление литосферы позволило глубинным расплавам проникать в литосферную мантию, образовав крупные очаги базитовых магм. Таким образом, современный геологический облик и металлогеническая специфика территории Восточного Казахстана является результатом плейт-тектонических процессов посторогенического растяжения на фоне повышенного термического градиента в мантии, вызванного активностью Таримского мантийного плюма.
Ключевые слова:	посторогенный магматизм; Центрально-Азиатский складчатый пояс; mantle-crust interaction; Tarim mantle plume; Post-orogenic magmatism; Central Asian Orogenic Belt; мантийно-коровое взаимодействие; Таримский плюм;
Издано:	2019
Физ. хар-ка:	с.79-99
Цитирование:	1. bramov S.S., 2004. Formation of fluorin-rich magmas by fluid filtration through silicic magmas: petrological and geochemical evidence of metamagmatism. Petrology 12 (1), 17-36. 2. Annikova I.Yu., Vladimirov A.G., Vystavnoi S.A., Zhuravlev D.Z., Kruk N.N., Lepekhina E.N., Matukov D.I., Moroz E.N., Palesskii V.S., Ponomarchuk V.A., Rudnev S.N., Sergeev S.A., 2006. U-Pb and 39Ar/40Ar dating and Sm-Nd and Pb-Pb isotopic study of the Kalguty molybdenum-tungsten ore-magmatic system, southern Altai. Petrology 14 (1), 81-97. https://doi.org/10.1134/S0869591106010073. 3. Barbarin B., 2005. Mafic magmatic enclaves and mafic rocks associated with some granitoids of the central Sierra Nevada batholith, California: nature, origin, and relations with the hosts. Lithos 80 (1-4), 155-177. https://doi.org/10.1016/j.lithos.2004.05.010. 4. Bryan S.E., Ernst R.E., 2008. Revised definition of large igneous provinces (LIPs). Earth-Science Reviews 86 (1-4), 175-202. https://doi.org/10.1016/j.earscirev.2007.08.008. 5. Burmakina G.N., Tsygankov A.A., 2013. Mafic microgranular enclaves in Late Paleozoic granitoids in the Burgasy quartz syenite massif, western Transbaikalia: Composition and petrogenesis. Petrology 21 (3), 280-303. https://doi.org/10.1134/S086959111303003X. 6. Burmakina G.N., Tsygankov A.A., Khubanov V.B., 2018. Petrogenesis of composite dikes in granitoids of western Transbaikalia. Russian Geology and Geophysics 59 (1), 19-40. https://doi.org/10.1016/j.rgg.2018.01.002. 7. Buslov M.M., 2011. Tectonics and geodynamics of the Central Asian Fold belt: The role of Late Paleozoic large-amplitude strike-slip faults. Russian Geology and Geophysics 52 (1), 52-71. https://doi.org/10.1016/j.rgg.2010.12.005. 8. Dobretsov N.L., 2003. Evolution of structures of the Urals, Kazakhstan, Tien Shan, and Altai-Sayan region within the Ural-Mongolian fold belt (Paleoasian ocean). Geologiya i Geofizika (Russian Geology and Geophysics) 44 (1-2), 5-27. 9. Dobretsov N.L., 2011. Early Paleozoic tectonics and geodynamics of Central Asia: Role of mantle plumes. Russian Geology and Geophysics 52 (12), 1539-1552. https://doi.org/10.1016/j.rgg.2011.11.003. 10. Ермолов П.В., Изох Э.П., Пономарёва А.П., Тян В.Д. Габбро-гранитные серии западной части Зайсанской складчатой системы. Новосибирск: Наука, 1977. 246 с 11. Ермолов П.В., Владимиров А.Г., Изох А.Э., Полянский Н.В., Кузебный В.С., Ревякин П.С., Борцов В.Д. Орогенный магматизм офиолитовых поясов (на примере Восточного Казахстана). Новосибирск: Наука, 1983. 191 с 12. Ernst R.E., 2014. Large Igneous Provinces. Cambridge University Press, Cambridge, 653 p. https://doi.org/10.1017/CBO9781139025300. 13. Ernst R.E., Buchan K.L., Campbell I.H., 2005. Frontiers in large igneous province research. Lithos 79 (3-4), 271-297. https://doi.org/10.1016/j.lithos.2004.09.004. 14. Furman T., Spera F.J., 1985. Co-Mingling of acid and basic magma with implications for the origin of mafic I-type xenoliths: field and petrochemical relations of an unusual dike complex at Eagle Lake, Sequoia National Park, California, U.S.A. Journal of Volcanology and Geothermal Research 24 (1-2), 151-178. https://doi.org/10.1016/0377-0273(85)90031-9. 15. Gao R., Xiao L., Pirajno F., Wang G.-C., He X.-X., Yang G., Yan Sh.-W., 2014. Carboniferous-Permian extensive magmatism in the West Junggar, Xinjiang, northwestern China: its geochemistry, geochronology, and petrogenesis. Lithos 204, 125-143. https://doi.org/10.1016/j.lithos.2014.05.028. 16. Huppert H.E., Sparks S.J., 1988. The generation of granitic magmas by intrusion of basalt into continental crust. Journal of Petrology 29 (3), 599-624. https://doi.org/10.1093/petrology/29.3.599. 17. Izokh A.E., Vishnevskii A.V., Polyakov G.V., Kalugin V.M., Oyunchimeg T., Shelepaev R.A., Egorova V.V., 2010. The Ureg Nuur Pt-bearing volcanoplutonic picrite-basalt association in the Mongolian Altay as evidence for a Cambrian-Ordovician Large Igneous Province. Russian Geology and Geophysics 51 (5), 521-533. https://doi.org/10.1016/j.rgg.2010.04.003. 18. Khromykh S.V., Burmakina G.N., Tsygankov А.А., Kotler P.D., Vladimirov A.G., 2017a. Interactions between gabbroid and granitoid magmas during formation of the Preobrazhensky intrusion, Eastern Kazakhstan. Geodynamics & Tectonophysics 8 (2), 311-330. https://doi.org/10.5800/GT-2017-8-2-0243. 19. Khromykh S.V., Kotler P.D., Sokolova E.N., 2017b. Mantle-crust interaction at the late stage of evolution of Hercynian Altai collision system, western part of CAOB. Geodynamics & Tectonophysics 8 (3), 489-493. https://doi.org/10.5800/GT-2017-8-3-0270. 20. Khromykh S.V., Kuibida M.L., Kruk N.N., 2011. Petrogenesis of high-temperature siliceous melts in volcanic structures of the Altai collisional system of Hercynides (Eastern Kazakhstan). Russian Geology and Geophysics 52 (4), 411-420. https://doi.org/10.1016/j.rgg.2011.03.004. 21. Khromykh S.V., Sokolova E.N., Smirnov S.Z., Travin A.V., Annikova I.Y., 2014. Geochemistry and age of rare-metal dyke belts in Eastern Kazakhstan. Doklady Earth Sciences 459 (2), 1587-1591. https://doi.org/10.1134/S1028334X14120174. 22. Khromykh S.V., Tsygankov A.A., Burmakina G.N., Kotler P.D., Sokolova E.N., 2018. Mantle-crust interaction in petrogenesis of gabbro-granite association in Preobrazhenka intrusion, Eastern Kazakhstan. Petrology 26 (4), 368-388. https://doi.org/10.1134/S0869591118040045. 23. Khromykh S.V., Tsygankov A.A., Kotler P.D., Navozov O.V., Kruk N.N., Vladimirov A.G., Travin A.V., Yudin D.S., Burmakina G.N., Khubanov V.B., Buyantuev M.D., Antsiferova T.N., Karavaeva G.S., 2016. Late Paleozoic granitoid magmatism of Eastern Kazakhstan and Western Transbaikalia: Plume model test. Russian Geology and Geophysics 57 (5), 773-789. https://doi.org/10.1016/j.rgg.2015.09.018. 24. Khromykh S.V., Vladimirov A.G., Izokh A.E., Travin A.V., Prokop'ev I.R., Azimbaev E., Lobanov S.S., 2013. Petrology and geochemistry of gabbro and picrites from the Altai collisional system of Hercynides: Evidence for the activity of the Tarim plume. Russian Geology and Geophysics 54 (10), 1288-1304. https://doi.org/10.1016/j.rgg.2013.09.011. 25. Kiselev A.I., Yarmolyuk V.V., Ivanov A.V., Egorov K.N., 2014. Middle Paleozoic basaltic and kimberlitic magmatism in the northwestern shoulder of the Vilyui Rift, Siberia: Relations in space and time. Russian Geology and Geophysics 55 (2), 144-152. https://doi.org/10.1016/j.rgg.2014.01.003. 26. Konopelko D., Seltmann R., Mamadjano Y., Romer R.L., Rojas-Agramonte Y., Jeffries T., Fidaev D., Niyozov A., 2017. A geotraverse across two paleo-subduction zones in Tien Shan, Tajikistan. Gondwana Research 47, 110-130. https://doi.org/10.1016/j.gr.2016.09.010. 27. Konopelko D., Wilde S.A., Seltmann R., Romer R.L., Biske Yu.S., 2018. Early Permian intrusions of the Alai range: Understanding tectonic settings of Hercynian post-collisional magmatism in the South Tien Shan, Kyrgyzstan. Lithos 302-303, 405-420. https://doi.org/10.1016/j.lithos.2018.01.024. 28. Kotler P.D., Khromykh S.V., Smirnov S.Z., D'yachkov B.A., Travin A.V., Vladimirov A.G., Yudin D.S., Kruk N.N., 2014. Ar-Ar isotopic dating of rare-metal pegmatites of the Kalba-Narym granite batholith (Eastern Kazakhstan). In: Granites and Earth's evolution: granites and continental crust. Proceedings of the 2nd International Geological Conference. IGM SB RAS, Novosibirsk, p. 104-105. 29. Kotler P.D., Khromykh S.V., Vladimirov A.G., Navozov O.V., Travin A.V., Karavaeva G.S., Kruk N.N., Murzintsev N.G., 2015. New data on the age and geodynamic interpretation of the Kalba-Narym granitic batholith, Eastern Kazakhstan. Doklady Earth Sciences 462 (2), 565-569. https://doi.org/10.1134/S1028334X15060136. 30. Kozlovsky A.M., Yarmolyuk V.V., Salnikova E.B., Travin A.V., Kotov A.B., Plotkina Ju.V., Kudryashova E.A., Savatenkov V.M., 2015. Late Paleozoic anorogenic magmatism of the Gobi Altai (SW Mongolia): Tectonic position, geochronology and correlation with igneous activity of the Central Asian Orogenic Belt. Journal of Asian Earth Sciences 113, 524-541. https://doi.org/10.1016/j.jseaes.2015.01.013. 31. Kuzmin M.I., Yarmolyuk V.V., 2014. Mantle plumes of Central Asia (Northeast Asia) and their role in forming endogenous deposits. Russian Geology and Geophysics 55 (2), 120-143. https://doi.org/10.1016/j.rgg.2014.01.002. 32. Levashova N.M., Van der Voo R., Abrajevitch A.V., Bazhenov M.L., 2009. Paleomagnetism of mid-Paleozoic subduction-related volcanics from the Chingiz Range in NE Kazakhstan: the evolving paleogeography of the amalgamating Eurasian composite continent. Geological Society of America Bulletin 121 (3-4), 555-573. https://doi.org/10.1130/B26354.1. 33. Li Y.Q., Li Z.L., Yu X., Langmuir Ch.H., Santosh M., Yang Sh.F., Chen H.L., Tang Zh.L., Song B., Zou S.Y., 2014. Origin of the Early Permian zircons in Keping basalts and magma evolution of the Tarim Large Igneous Province (northwestern China). Lithos 204, 47-58. https://doi.org/10.1016/j.lithos.2014.05.021. 34. Litvinovsky B.A., Zanvilevich A.N., Kalmanovich M.A., 1995. The repeated mixing and mingling of coeval syenite and basalt magmas and its role in petrogenesis: a case study in the Ust’ Khilok pluton, Transbaikalia (Russia). Petrology 3 (2), 125-137. 35. Лопатников В.В., Изох Э.П., Ермолов П.В., Пономарева А.П., Степанов А.С. Магматизм и рудоносность Калба-Нарымской зоны Восточного Казахстана. М.: Наука, 1982. 248 с 36. Mekhonoshin A.S., Kolotilina T.B., Vladimirov A.G., Sokol'nikova Yu.V., Doroshkov A.A., 2017. First data on the concentrations and distribution of noble metals in Ni-Cu sulfide ores of the South Maksut deposit (Eastern Kazakhstan). Geodynamics & Tectonophysics 8 (3), 515-519. https://doi.org/10.5800/GT-2017-8-3-0278 37. Pirajno F., Seltmann R., Yang Y., 2011. A review of mineral systems and associated tectonic settings of northern Xinjiang, NW China. Geosciences Frontiers 2 (2), 157-185. https://doi.org/10.1016/j.gsf.2011.03.006 38. Polyakov G.V., Izokh A.E., Borisenko A.S., 2008. Permian ultramafic-mafic magmatism and accompanying Cu-Ni mineralization in the Gobi-Tien Shan belt as a result of the Tarim plume activity. Russian Geology and Geophysics 49 (7), 455-467. https://doi.org/10.1016/j.rgg.2008.06.001 39. Renna M.R., Tribuzio R., Tiepolo M., 2006. Interaction between basic and acid magmas during the latest stages of the post-collisional Variscan evolution: Clues from the gabbro-granite association of Ota (Corsica-Sardinia batholith). Lithos 90 (1-2), 92-110. https://doi.org/10.1016/j.lithos.2006.02.003 40. Safonova I., Komiya T., Romer R.L., Simonov V., Seltmann R., Rudnev S., Yamamoto S., Sun M., 2018. Supra-subduction igneous formations of the Char ophiolite belt, East Kazakhstan. Gondwana Research 59, 159-179 https://doi.org/10.1016/j.gr.2018.04.001 41. Safonova I.Y., Simonov V.A., Kurganskaya E.V., Obut O.T., Romer R.L., Seltmann R., 2012. Late Paleozoic oceanic basalts hosted by the Char suture-shear zone, Eastern Kazakhstan: Geological position, geochemistry, petrogenesis and tectonic setting. Journal of Asian Earth Sciences 49, 20-39. https://doi.org/10.1016/j.jseaes.2011.11.015 42. Seltmann R., Konopelko D., Biske G., Divaev F., Sergeev S., 2011. Hercynian post-collisional magmatism in the context of Paleozoic magmatic evolution of the Tien Shan orogenic belt. Journal of Asian Earth Sciences 42 (5), 821-838. https://doi.org/10.1016/j.jseaes.2010.08.016 43. Şengör A.M.C., Natal'in B.A., Burtman U.S., 1993. Evolution of the Altaid tectonic collage and Paleozoic crustal growth in Eurasia. Nature 364 (6435), 299-304. https://doi.org/10.1038/364299a0 44. Щерба Г.Н., Дьячков Б.А., Нахтигаль Г.П. Жарма-Саурский геотектоноген. Алма-Ата: Наука, 1976. 198 с 45. Щерба Г.Н., Дьячков Б.А., Стучевский Н.И., Нахтигаль Г.П., Антоненко А.Н., Любецкий В.Н. Большой Алтай (геология и металлогения). Кн. 1. Геологическое строение. Алматы: Гылым, 1998. 304 с 46. Sokolova E.N., Smirnov S.Z., Khromykh S.V., 2016. Conditions of crystallization, composition, and sources of rare-metal magmas forming ongonites in the Kalba-Narym zone, Eastern Kazakhstan. Petrology 24 (2), 153-177. https://doi.org/10.1134/S0869591116020065 47. Vladimirov A.G., Izokh A.E., Polyakov G.V., Babin G.A., Mekhonoshin A.S., Kruk N.N., Khlestov V.V., Khromykh S.V., Travin A.V., Yudin D.S., Shelepaev R.A., Karmysheva I.V., Mikheev E.I., 2013. Gabbro-granite intrusive series and their indicator importance for geodynamic reconstructions. Petrology 21 (2), 158-180. https://doi.org/10.1134/S0869591113020070 48. Vladimirov A.G., Kruk N.N., Khromykh S.V., Polyansky O.P., Chervov V.V., Vladimirov V.G., Travin A.V., Babin G.A., Kuibida M.L., Khomyakov V.D., 2008. Permian magmatism and lithospheric deformation in the Altai caused by crustal and mantle thermal processes. Russian Geology and Geophysics 49 (7), 468-479. https://doi.org/10.1016/j.rgg.2008.06.006 49. Vladimirov A.G., Kruk N.N., Rudnev S.N., Khromykh S.V., 2003. Geodynamics and granitoid magmatism of collision orogens. Geologiya i Geofizika (Russian Geology and Geophysics) 44 (12), 1321-1338 50. Vorontsov A.A., Fedoseev G.S., Andryushchenko S.V., 2013. Devonian volcanism in the Minusa basin in the Altai-Sayan area: geological, geochemical, and Sr-Nd isotopic characteristics of rocks. Russian Geology and Geophysics 54 (9), 1001-1025. https://doi.org/10.1016/j.rgg.2013.07.016 51. Wang B., Cluzel D., Jahn B-M., Shu L., Chen Y., Zhai Y., Branquet Y., Barbanson L., Sizaret S., 2014. Late Paleozoic pre- and syn-kinematic plutons of the Kangguer-Huangshan Shear zone: Inference on the tectonic evolution of the eastern Chinese north Tianshan. American Journal of Science 314 (1), 43-79. https://doi.org/10.2475/01.2014.02 52. Wei X., Xu Y.-G., Feng Y.-X., Zhao J.-X., 2014. Plume-lithosphere interaction in the generation of the Tarim Large Igneous Province, NW China: geochronological and geochemical constraints. American Journal of Science 314 (1), 314-356. https://doi.org/10.2475/01.2014.09 53. Wiebe R.A., 1973. Relations between coexisting basaltic and granitic magmas in a composite dike. American Journal of Sciences 273 (2), 130-151. https://doi.org/10.2475/ajs.273.2.130 54. Windley B.F., Alexeiev D., Xiao W., Kröner A., Badarch G., 2007. Tectonic models for accretion of the Central Asian Orogenic Belt. Journal of the Geological Society 164 (1), 31-47. https://doi.org/10.1144/0016-76492006-022 55. Xiao W.J., Han C.M., Yuan C., Sun M., Lin S.F., Chen H.L., Li Z.L., Li J.L., Sun S., 2008. Middle Cambrian to Permian subduction-related accretionary orogenesis of North Xinjiang, NW China: implications for the tectonic evolution of Central Asia. Journal of Asian Earth Sciences 32 (2-4), 102-117. https://doi.org/10.1016/j.jseaes.2007.10.008 56. Xiao W.J., Huang B., Han Ch., Sun Sh., Li J., 2010. A review of the western part of the Altaids: A key to understanding the architecture of accretionary orogens. Gondwana Research 18 (2-3), 253-273. https://doi.org/10.1016/j.gr.2010.01.007 57. Xiao W., Santosh M., 2014. The western Central Asian Orogenic Belt: a window to accretionary orogenesis and continental growth. Gondwana Research 25, 1429-1444. https://doi.org/10.1016/j.gr.2014.01.008 58. Xu Y-G., Wei X., Luo Z-Y., Liu H-Q., Cao J., 2014. The Early Permian Tarim Large Igneous Province: Main characteristics and a plume incubation model. Lithos 204, 20-35. https://doi.org/10.1016/j.lithos.2014.02.015 59. Yarmolyuk V.V., Kuzmin M.I., Ernst R.E., 2014. Intraplate geodynamics and magmatism in the evolution of the Central Asian Orogenic Belt. Journal of Asian Earth Sciences 93, 158-179. https://doi.org/10.1016/j.jseaes.2014.07.004 60. Yu X., Yang S.F., Chen H.L., Chen Z.Q., Li Z.L., Batt G.E., Li Y.Q., 2011. Permian flood basalts from the Tarim Basin, Northwest China: SHRIMP zircon U-Pb dating and geochemical characteristics. Gondwana Research 20 (2-3), 485-497. https://doi.org/10.1016/j.gr.2010.11.009 61. Yu X., Yang S.F., Chen H.L., Li Z.L., Li Y.Q., 2017. Petrogenetic model of the Permian Tarim Large Igneous Province. Science China Earth Sciences 60 (10), 1805-1816. https://doi.org/10.1007/s11430-016-9098-7 62. Zagorsky V.Ye., Vladimirov A.G., Makagon V.M., Kuznetsova L.G., Smirnov S.Z., D’yachkov B.A., Annikova I.Yu., Shokalsky S.P., Uvarov A.N., 2014. Large fields of spodumene pegmatites in the settings of rifting and postcollisional shear-pull-apart dislocations of continental lithosphere. Russian Geology and Geophysics 55 (2), 237-251. https://doi.org/10.1016/j.rgg.2014.01.008 63. Zhang Ch.L., Li Z.X., Li X.H., Xu Y.G., Zhou G., Ye H.M., 2010. A Permian large igneous province in Tarim and Central Asian orogenic belt, NW China: Results of a ca. 275 Ma mantle plume? Geological Society of America Bulletin 122 (11-12), 2020-2040. https://doi.org/10.1130/B30007.1 64. Zhang Ch.L., Zou H.B., Yao Ch.Y., Dong Y.G., 2014. Origin of Permian gabbroic intrusions in the southern margin of the Altai Orogenic belt: A possible link to the Permian Tarim mantle plume? Lithos 204, 112-124. https://doi.org/10.1016/j.lithos.2014.05.019