Document Type : Original Research Paper
Authors
Department of Geology, Faculty of Basic Sciences, Bu-Ali Sina University, Hamadan, Iran
Abstract
One of the common processes that lead to the formation and enrichment of precious metal deposits is boiling. The existence of a spatial relation between fluid boiling and deposition of precious metals is a valuable tool in exploration of epithermal deposits. Therefore, the investigating of the process occurrence in epithermal deposits will be able to predict the continuation of exploration trend. Chah-Morad epithermal gold deposit is located in 75 km northwest of Bazman in the Sistan and Baluchistan Province and in the Makran-Chagai Magmatic Arc southeast of Iran. The mineralization in the Chah-Morad deposit occurred in 3 stages and in quartz veins that exist between the altered argillic alteration zone and dacite and rhyodacite sub-volcanic rocks. Textural mineralogical and fluid inclusions studies indicate the occurrence of the boiling process in this deposit. The most important kinds of evidence for the occurrence of this process are: a) the presence of adularia, b) platy calcite texture, c) breccia, crustiform-colloform textures, d) different liquid-vapor ratios of fluid inclusions, e) the increase in the salinity of fluid inclusions with the decrease in homogenization temperatures, f) the coexistence of fluid inclusions with different salinities and g) co-existing liquid single-phase fluid inclusions with vapor single-phase fluid inclusions. Therefore, the existance of boiling is confirmed in the Chah-Morad deposit.
Keywords
Main Subjects
Adams, S. F., 1920. A microscopic study of vein quartz. Economic Geology, 15 (8), 623-664. https://doi.org/10.2113/gsecongeo.15.8.623.
Agard, P., Omrani, J., Jolivet, L., and Mouthereau, F., 2005. Convergence history across Zagros (Iran): Constraints from collisional and earlier deformation, International Journal of Earth Sciences, 94, 401-419. http://dx.doi.org/10.1007/s00531-005-0481-4.
Albinson, T., Norman, D. I., Cole, D., and Chomiak B., 2001. Controls on formation of low-sulfidation epithermal deposits in Mexico: Constraints from fluid inclusion and stable isotope data. Society of Economic Geologists Special Publication, 8, 1-32.https://doi.org/10.5382/SP.08.01.
Aliani, F., Maanijou, M., Sabouri, Z., Sepahi, A. A., 2012. Petrology, geochemistry and geotectonic environment of the Alvand Intrusive Complex, Hamedan, Iran, Chemie der Erde., 72 (4), 363-383. https://doi.org/10.1016/j.chemer.2012.05.001.
Amini, L., Maanijou, M., Jannessary, M. R., and FathTabar, S., 2022. Alteration zone detection of Chah-Morad gold deposit using ASTER images. 12th symposium of Iranian Society of Economic Geology, Bu-Ali Sina university, Hamedan. Iran. 623-632. (In persian).
Amraei, S., and Niroomand, Sh. 2016. Mineralogy, Alterations, Lithogeochemical Investigations and Fluid Inclusions Studies in Kudkan Cu-Au Mineralization Area, Southern Khorasan, Iran, Vol 6, Issue 1, S.N.19, p. 34-47. https://doi.org/10.22055/aag.2016.12143. (In persian).
André-Mayer, A.-S., Leroy, J., Bailly, L., Chauvet, A., Marcoux, E., Grancea, L., Llosa, F., and Rosas, J., 2002. Boiling and vertical mineralization zoning: a case study from the Apacheta low-sulfidation epithermal gold-silver deposit, south Peru. Mineralium Deposita, 37, 452 - 464. http://dx.doi.org/10.1007/s00126-001-0247-2.
Berberian, M., and King, G.C.P., 1981. Towards a paleogeography and tectonic evolution of Iran, Canadian Journal of Earth Sciences, 18, 210–265. https://doi.org/10.1139/e81-019.
Berger, B. R., and Eimon, P., 1983. Conceptual models of epithermal precious metal deposits. In: Shanks WC III Cameron volume on unconventional mineral deposits. Australasian Institute of Mining and Metallurgy, 91–205.
Biabangard, H., and Moradian, A., 2008. Geology and geochemical evaluation of TaftanVolcano, Sistan and Baluchestan Province, southeast of Iran, Chinese Journal ofGeochemistry, 27, 356-369. https://dx.doi.org/10.1007/s11631-008-0356.
Bigdeli, R., Tale Fazel, E., Maanijou, M., 2021. Mineralization, ore mineral chemistry and sulfur stable isotopes at the Chaldaq gold prospect (north Takab): evidence for gold formation mechanism. Journal of Economic Geology, 13 (1), 85-111. https://dx.doi.org/10.22067/econg.v13i1.83781.
Bodnar, R. J., 1992. Revised equation and table for determininig the freezing point depression of H2O-NaCl solutions, Geochemica et Cosmochimica Acta, 57, 683-684.
Bodnar, R. J., Reynolds, T. J., and Kuehn, C. A., 1985. Fluid-inclusion systematics in epithermal systems. Reviews in Economic Geolology, 2, 1–24. https://doi.org/10.5382/Rev.02.05.
Browne, P. R. L., 1978. Hydrothermal alteration in active geothermal fields. Annual Review of Earth and Planetary Sciences 6, 229–248. https://doi.org/10.1146/annurev.ea.06.050178.001305.
Browne, P. R. L., and Ellis, A.J., 1970. The Ohaki-Broadlands hydrothermal area, New Zealand, mineralogy and related geochemistry. Am. J. Sci. 269, 97–131. https://doi.org/10.2475/ajs.269.2.97.
Buchanan, L. J., 1981. Precious metal deposits associated with volcanic environments in the Southwest. Arizona Geological Society Digest, 14, 237-262.
Candela, Ph., A., 1997. A Review of Shallow, Ore-related Granites: Textures, Volatiles, and Ore Metals.Journal of Petrology, 38 (12), 1619–1633, https://doi.org/10.1093/petroj/38.12.1619.
Canet, C., Franco, S.I., Prol-Ledesma, R.M., González-Partida, E., and Villanueva-Estrada, R.E., 2011. A model of boiling for fluid inclusion studies: application to the Bolaños Ag– Au–Pb–Zn epithermal deposit, Western Mexico. J. Journal of Geochemical Exploration, 110 (2), 118 – 125. https://doi.org/10.1016/j.gexplo.2011.04.005.
Christie, A. B., Simpson, M. P., Brathwaite, R. L., Mauk, J. L., and Simmons, S. F., 2007. Epithermal Au-Ag and related deposits of the Hauraki goldfield, Coromandel volcanic zone, New Zealand. Economic Geology, 102 (5), 785–816. https://doi.org/10.2113/gsecongeo.102.5.785.
Cline, J. S., Bodnar, R. J., and Rimstidt, J. D., 1992. Numerical simulation of fluid flow and silica transport and deposition in boiling hydrothermal solutions: Application to epithermal gold deposits. Journal of Geophysical Research, 97, B6, 9085-9103. https://doi.org/10.1029/91JB03129.
Cole, D. R., and Drummond, S. E., 1986. The effect of transport and boiling on Ag/Au ratios in hydrothermal solutions: a preliminary assessment and possible implications for the formation of epithermal precious-metal ore deposits. Geochem Explor, 25 (1-2), 45–79, https://doi.org/10.1016/0375-6742 (86)90007-5.
Cooke, D. R., and Simmons, S. F., 2000. Characteristics and genesis of epithermal gold deposits. Economic Geology, 13, 221–244, https://doi.org/10.5382/Rev.13.06.
Dong, G., and Morrison, G. W., 1995. Adularia in epithermal veins, Queensland; morphology, structural state and origin. Miner Deposita, 30, 11-19, doi:10.1007/BF00208872.
Dong, G., Morrison, G., and Jaireth, S., 1995. Quartz textures in epithermal veins, Queensland; classification, origin and implication. Economic Geology, 90 (6), 1841-1856, http://dx.doi.org/10.2113/gsecongeo.90.6.1841.
Dong, L. L., Wan, B., Deng, C., Cai, K. D., and Xiao, W.J., 2018. An Early Permian epithermal gold system in the Tulasu Basin in North Xinjiang, NW China: constraints from in situ oxygen-sulfur isotopes and geochronology. Asian Earth Sci. 153, 412–424,doi: 10.1016/j.jseaes. 2017.07.044.
Drummond, S. E., and Ohmotto, H., 1985. Chemical evolution and mineral deposition in boiling hydrothermal systems. Economic Geology, 80, 126–147, https://doi.org/10.2113/gsecongeo.80.1.126.
Esmaeli, M., Lotfi, M., and Nezafati, N., 2015. Fluid inclusion and stable isotope study of theKhalyfehlou copper deposit, southeast Zanjan, Iran. Arab. J. Geosci, 8, 9625–9633, https://doi.org/10.1007/s12517-015-1907-3.
Fazeli, T., 2019. Tourmaline chemistry and fluid inclusion studies of brecciated hydrothermal Au-bearing quartz-tourmaline veins at Sari Gunay deposit, Ghorveh, Kurdistan, Thesis Submitted for Degree of Masters of Science, Kharazmi University, Factulty of Earth Sciences, Department of Geochemistry, 130 p. (In persian).
Fournier, R.O., 1985. The behavior of silica in hydrothermal solution. Economic Geology. 2, https://doi.org/10.5382/Rev.02.03.
Ghalamghash, J., Schmitt, A. K., Shiaian, K., Jamal, R., and Sun-Lin Chung, 2018. Magma origins and geodynamic implications for the Makran-Chagai arcfrom geochronology and geochemistry of Bazman volcano, Southeastern Iran. Journal of Asian Earth Sciences, 171, 2-53, https://doi.org/10.1016/j.jseaes.2018.12.006.
Glennie, K. W., 2000. Cretaceous tectonic evolution of Arabia eastern plate margin of two oceanic, in Middle East models of Jurassic/Cretaceous carbonates systems, SEPM, Special Publications, Tulsa, USA, 69, 9-20, https://doi.org/10.2110/pec.00.69.0009.
Grof, J. A. 2019. Evidence of boiling and epithermal vein mineralization in Carlin-type deposits on the Getchell trend, Nevada, Ore Geology Reviewsogy Reviews, 106, 340–350, https://doi.org/10.1016/j.oregeorev.2019.02.013.
Gunnarsson, I., and Arnórsson, S., 2000. Amorphous silica solubility and the thermodynamic properties of H4SiO°4 in the range 0° to 350°C at Psat, Geochimica et Cosmochimica Acta, 64 (13), 2295-2307, http://dx.doi.org/10.1016/S0016-7037(99)00426-3.
Haas, J. L., 1971. The effect of salinity on the maximum thermal gradient of a hydrothermal system at hydrostatic pressure. Economic Geology, 66 (6), 940–946, https://doi.org/10.2113/gsecongeo.66.6.940.
Heald, P., Floey, N. K., and Hayba, D. O., 1987. Comparative anatomy of volcanic-hosted epithermal deposits: Acid-sulfate and adularia-sericite types. Economic Geology, 82 (1), 1–26, http://dx.doi.org/10.2113/gsecongeo.82.1.1.
Hedenquist, J. W., and Arribas, A., 2017. Epithermal ore deposits: first-order features relevant to exploration and assessment. Mineral Resources to Discover - 14th SGA Biennial Meeting 2017, 1, 47-50.
Hedenquist, J. W., and Henley, R. W., 1985. The importance of CO2 on freezing point measurements of fluid inclusions; Evidence from active geothermal systems and implications for epithermal ore deposition, Economic Geology, 80 (5), 1379-1406, https://doi.org/10.2113/gsecongeo.80.5.1379.
Hedenquist, J. W., Arribas, A., and Gonzalez - Urien, E., 2000. Exploration for epithermal gold deposits. Economic Geology, 13, 245–277, https://doi.org/10.5382/Rev.13.07.
Hedenquist, J. W., Sillitoe, R. H., and Arribas, A., 2004. Characteristics of and exploration for high-sulfidation epithermal Au-Cu deposits. In: Cooke, D. R., Deyell, C. L., Pongratz, J., (eds.), 24 Carat Gold Workshop: Centre for Ore Deposit Research, Special Publication, 5:99-110.
Helgeson, H. C., 1969. Thermodynamics of hydrothermal systems at elevated temperatures and pressures. American Journal of Science, 267 (7), 729-804, https://doi.org/10.2475/ajs.267.7.729.
Henley, R. W., and Brown, K. L., 1985. A practical guide to the thermodynamics of geothermal fluids and hydrothermal ore deposits. Reviews in Economic Geology, 2, 25-44, https://doi.org/10.5382/Rev.02.02.
Henley, R. W., and Ellis, A. J., 1983. Geothermal systems ancient and modern: a geochemical review. Earth Science Reviews, 19, 1-50, https://doi.org/10.1016/0012-8252(83)90075-2.
Henley, R. W., and Hughes, G. O., 2000. Underground fumaroles: "Excess heat" effects in vein formation. Economic Geology, 95 (3), 453-466, https://doi.org/10.2113/gsecongeo.95.3.453.
Henley, R. W., Truesdell, A. H., and Barton, P. B., Jr., 1984. Fluid-mineral equilibria in hydrothermal systems: Society of Economic Geologists, Reviews in Economic Geology, 1, 267 p, https://doi.org/10.5382/Rev.01.
Herdianita, N. R., Rodgers, K. A., and Browne, P. R. L., 2000. Routine instrumental procedures to characterise the mineralogy of modern and ancient silica sinters, Geothermics, 29, 65-81, https://doi.org/10.1016/S0375-6505%2899%2900054-1.
Jébrak, M., 1997. Hydrothermal breccias in vein - type ore deposits: a review of mechanisms, morphology and size distribution. Ore Geology Reviews, 12 (3), 111–134, https://doi.org/10.1016/S0169-1368(97)00009-7.
Jobson, D. H., Boulter, C. A., Foster, R. P., 1994. Structural controls and genesis of epithermal gold-bearing breccias at the Lebong Tandai mine, Western Sumatra, Indonesia. Journal of Geochemical Exploration, 50 (1-3), 409–428, https://doi.org/10.1016/0375-6742(94)90034-5.
Koděra, P., Lexa, J., Fallick, A. E., Wälle, M., and Biroň, A., 2014. Hydrothermal fluids in epithermal and porphyry Au deposits in the Central Slovakia Volcanic Field. Geological Society London Special Publications, 402 (1), 177–206, http://dx.doi.org/10.1144/SP402.5.
Maanijou, M., and Ferdowsi Rashed, M., 2021. Fluid inclusions and sulfur stable isotopes of the Sarab 3 iron ore deposit (the Shahrak mining area-north Bijar), Journal of Economic Geology, 12 (4), 531-561, Doi.10.22067/ECONG.V12I4.78330.
Maanijou, M., Rasa, I., and Lentz, D., 2012, Petrology, Geochemistry, and Stable Isotope Studies of the Chehelkureh Cu-Zn-Pb deposit, Zahedan, Economic Geology, 107 (4), 683– 712. https://doi.org/10.2113/econgeo.107.4.683.
Moncada, D., 2008. Application of fluid inclusions and mineral texture in exploration for epithermal precious metals deposits. Thesis submitted to the faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirement for the degree of Master of Science in Geosciences.
Moncada, D., Mutchler, S., Niebto, A., Reynolds, T. J., Rimstidt, J. D., and Bodnar, R. J., 2012. Mineral textures and fluid inclusion petrography of the epithermal Ag-Au deposits at Guanajuato, Mexico: Application to exploration. Journal of Geochemical Exploration, 114(12): 20–35, https://doi.org/10.1016/j.gexplo.2011.12.001.
Omidvar, M, 2022. Geological map of Chah-Morad. Scale 1:1000, Geological survey and mineral explorations of Iran. (In persian).
Parry, W. T., and Bruhn, R. L., 1990. Fluid Pressure Transients on Seismogenic Normal Faults, Tectonophysics 179 (1-3), 335-344, https://doi.org/10.1016/0040-1951(90)90299-N.
Pirajno, F. 2009. Metalliferous sediments and sedimentary rock-hosted stratiform and/or stratabound hydrothermal mineral systems. In Hydrothermal Processes and Mineral Systems (pp. 727-883). Springer, Dordrecht.
Rahmani, Sh., 2019. Gold Mineralization in Tarom belt with Specific Reference to Lohneh (Lubin) - Zardeh Gold deposit (NW Iran). A thesis Presented for the degree of PhD of Science in Economic Geology. Lorestan University, Faculty of Basic Sciences, Department of Geology. 308 p. (In persian).
Richards, J. P., and Sholeh, A., 2016. The Tethyan tectonic history and Cu-Au metallogeny of Iran, Tectonics and Metallogeny of the Tethyan Orogenic Belt, Society of Economic Geologists Special Publication No. 19, 193–212, https://doi.org/10.5382/SP.19.07.
Richards, J.P., Spell, T., Rameh, E., Razique, A., and Flectcher, T., 2012, High Sr/Y magmas reflect arc maturity, high magmatic water content, and porphyry Cu ± Mo ± Au potential: Examples from the Tethyan arcs of central and eastern Iran and western Pakistan: Economic Geology, v. 107, p. 295–332. DOI:10.2113/econgeo.107.2.295.
Rinne, M. L., Cooke, D. R., Harris, A. C., Finn, D. J., Allen, C. M., Heizler, M. T., and Creaser, R. A., 2018. Geology and geochronology of the Golpu porphyry and Wafi epithermal deposit, Morobe Province, Papua New Guinea. Economic Geology, 113 (1), 271–294, https://doi.org/10.5382/econgeo.2018.4551.
Roedder, E., 1984. Fluid inclusions. Rev. Mineral, 12, 646p.
Roedder, E., and Bodnar, R.J., 1997. Fluid inclusion studies of hydrothermal ore deposits. In: Barnes, H.L. Ed., Geochemistry of Hydrothermal Ore Deposits. Wiley, New York, pp. 657– 697.
Rogers, A.F., 1918. The occurrence of cristobalite in California. American Journal of Science, 45 (267), 222–226.
Salehi Yazdi, M., Ghorbani, M., Nezafati, N., and Vossoughi Abedini, M. 2022. The role of basement and young magmatism in epithermal gold and polymetallic mineralization in Takab-Mahneshan area, NW Iran, Scientific Quartely Journal, Geosciences, vol 32, Issue. 3, Serial No. 125. 145-158. https://sid.ir/paper/1040230/fa. (In persian).
Sander, M. V., and Black, J. E., 1988. Crystallization and recrystallization of growthzoned vein quartz crystals from epithermal systems: implications for fluid inclusion studies. Economic Geology, 83 (5), 1052-1060, https://doi.org/10.2113/gsecongeo.83.5.1052.
Scott, A. M., and Watanabe, Y., 1998. Extreme boiling model for variable salinity of the Hokko low sulfidation epithermal Au prospect, southwestern Hokkaido, Japan. Mineralium Deposita, 33, 568–578, https://doi.org/10.1007/S001260050173.
Scott, S., Gunnarsson, I., Arnórsson, S., and Stefánsson, A., 2014. Gas chemistry, boiling and phase segregation in a geothermal system, Hellisheidi, Iceland. Geochim. Cosmochim. Acta, 124, 170–189, https://doi.org/10.1016/j.gca.2013.09.027.
Sebere, D., Vallve, M., Sandvol, E., Steer, D., and Barazangi, M., 1997. Middle East tectonics, applications of Geographic information systems (IGS). Gas today, 7 (2):1-6.
Seward, T. M., 1989. The hydrothermal chemistry of gold and its implicationsfor ore formation: boiling and conductive cooling asexamples. Economic Geology, 6, 394–404, https://doi.org/10.5382/Mono.06.31.
Seward, T. M., and Barnes, H. L., 1997. Metal transport by hydrothermal ore fluids. In: Barnes, H.L. (Ed.), Geochemistry of hydrothermal ore deposits. John Wiley and Sons, New York, pp. 435–486.
Shenberger, D. M., and Barnes, H. L., 1989. Solubility of gold in aqueous sulfide solutions from 150 to 350°C. Geochimica et Cosmochimica Acta, 53 (2), 269-278, https://doi.org/10.1016/0016-7037(89)90379-7.
Shiaian, K., Ghalamghash, J., N., Vossoughi Abedini, M., and Masoudi, F., 2016. Geology, Geochemistry and petrogenesis of Bazman Volcano, SE of Iran. Scientific Quartely Journal, Geosciences, vol 24, Issue. 95, 99-110. https://doi.org/10.22071/gsj.2015.42387. (In persian).
Shimizu, T., 2014. Reinterpretation of quartz textures in terms of hydrothermal fluid evolution at the koryu Au-Ag deposit. Economic Geology, 109 (7), 2051–2065, https://doi.org/10.2113/econgeo.109.7.2051.
Sholeh, A., Rastad, E., Huston, D.J., Gemmell, B., and Taylor, R.D., 2016. The Chahnaly low-sulfidation epithermal gold deposit, Western Makran Volcanic Arc, Southeast Iran. Economic Geology, 111, 619–639, https://doi.org/10.2113/econgeo.111.3.619.
Siddiqui, R. H., Khan, M. A., Qasim Jan, M., and Ogasawara, M., 2009. Petrogenesis of Plio-Pleistocene volcanic rocks from the Chagai arc, Balochistan, Pakistan, Journal of Himalayan Earth Sciences, 42, 1-24.
Sillitoe, R.H., and Hedenquist, J. W., 2003. Linkages between volcanotectonic settings, ore-fluid compositions, and epithermal precious-metal deposits. In Simmons SF, Graham I (eds) Soc Economic Geology Spec Pub, 10, 315-343, https://doi.org/10.5382/SP.10.16.
Simmons, S. F., and Browne, P. R. L., 2000. Hydrothermal minerals and precious metals in the Broadlands-Ohaaki geothermal system: Implications for understanding low-sulfidation epithermal environments. Economic Geology, 95, 971–1000, https://doi.org/10.2113/gsecongeo.95.5.971.
Simmons, S. F., and Christenson, B. W., 1994. Origins of calcite in a boiling geothermal system. American Journal of Science, 294 (3), 361-400, https://doi.org/10.2475/ajs.294.3.361.
Simmons, S. F., Simpson, M. P., and Reynolds, T. J., 2007. The significance of clathrates in fluid inclusions and the evidence for overpressuring in the broadlands-Ohaaki geothermal system, New Zealand. Economic Geology, 102, 127–135, https://doi.org/10.2113/gsecongeo.102.1.127.
Simmons, S. F., White, N. C., and John, D. A., 2005. Geological characteristics of epithermal precious and base metal deposits. In: Hedenquist, J.W., Thompson, J.F.H., Goldfarb, J.R., Richards, J.P. (Eds.), Economic Geology. 100th Ann. Vol., pp. 485–522, https://doi.org/10.5382/AV100.16.
Simpson, C. R. J., 1996. The formation of banded epithermal quartz veins at the Golden Cross mine, Waihi, New Zealand. MSc Thesis, University of Auckland, pp 100.
Simpson, C. R. J., Mauk, J. L., and Arehart, G. B., 1995. The formation of banded epithermal quartz veins at the Golden Cross mine, Waihi, New Zealand. Pacrim Congress ’95, Australasian Institute of Mining and Metallurgy, p. 455-450
Simpson, M. P., Mauk, J. L., and Simmons, S. F., 2001. Hydrothermal alteration and hydrologic evolution of the Golden Cross Epithermal Au–Ag deposit, New Zealand. Economic Geology, 96 (4), 773–796, https://doi.org/10.2113/gsecongeo.96.4.773.
Sorby, H. C., 1858. On the microscopic structure of crystals, indicating the origin of minerals and rocks. Quart. Journal of the Geological Society. London 14, 453–500, https://doi.org/10.1144/GSL.JGS.1858.014.01-02.44.
Taylor, P. S., 1971. Mineral variations in the silver veins of Guanajuato, Mexico., Unpublished Ph. D. dissertation, Dartmouth College, Hanover, NH, 136 pp.
Van den Kerkhof, A. M., and Hein, U. F., 2001. Fluid inclusion petrography. Lithos, 55(1-4), 27-47, https://doi.org/10.1016/S0024-4937(00)00037-2.
Wanga, L., Qina, Zh-K., Songc, G., and Li, G-M. 2019. A review of intermediate sulfidation epithermal deposits and subclassification. Ore Geology Reviews, 107. 434–456, https://doi.org/10.1016/j.oregeorev.2019.02.023.
Wilkinson, J. J., 2001. Fluid inclusions in hydrothermal ore deposits. Lithos 55, 229–272, http://dx.doi.org/10.1016/S0024-4937(00)00047-5.
Zamanian, H., Rahmani, Sh., Zareisahamieh, R., Pazokia, A., and Yang, X. Y., 2020. Geochemical characteristics of igneous host rocks of Lubin-Zardeh Au-Cu deposit, NW Iran. Ore Geology Reviews, 122, 103496, https://doi.org/10.1016/j.oregeorev.2020.103496.
)