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Leonid Neymark

Leonid Neymark is a Scientist Emeritus with the Geology, Geophysics, and Geochemistry Science Center.

I am currently a Scientist Emeritus in the Geology, Geophysics, and Geochemistry Science Center after being transferred from the Geochemistry Team, Yucca Mountain Project Branch where I conducted U-series studies of soils, fracture minerals and water-rock interaction processes.

I conduct a wide spectrum of isotope-geochemical studies involving radiogenic isotopes of U, Pb, Sr, and Nd and using ICP-MS and TIMS techniques. Before 2010 I was a principal investigator and a member of the Geochemistry Team in the Yucca Mountain Project Branch, WRD. The team's task was to evaluate geochemical aspects of the hydrogeologic suitability of Yucca Mountain to permanently store high-level radioactive waste. My focus was on the history of secondary mineral deposition (largely calcite and silica) in soil and unsaturated- and saturated-zone settings and on isotope-geochemical indicators of water-rock interaction as evidence of past water flow. These studies used U-Pb and U-series and other isotope-geochemical methods to characterize the timing of low-temperature surface processes of mineral deposition and to evaluate past water-rock interaction. In 2004 I was closely involved in the installation and detailed testing of a new ThermoFinnigan thermal-ionization mass-spectrometer Triton. I developed reproducible mass-spectrometric methods of U-series isotope measurements for whole rock samples with large Th/U and 232Th/230Th ratios. Previous YMPB work included systematic characterization of subsurface and soil hydrogenic minerals to provide a basis for understanding past hydrologic and climate variability in the Yucca Mountain region.

Current Projects

  • Sources of Pb contamination in domestic well water in SW Missouri
  • Matrix Pore Waters - Ultracentrifugation Method for Low-Permeability Sedimentary and Crystalline Rocks
  • The U-Th-Pb whole-rock isotope system in the Chalk River core and past redox conditions
  • Impact of Exhalative Hydrothermal Systems on Marine Chemistry: Applications for Mineral Assessment
  • Conditions and Processes Affecting Radionuclide Transport (writing a chapter for the GSA Memoir devoted to Yucca Mountain, volume 2

Professional Experience

  • Research Chemist, Geology, Geophysics, and Geochemistry Science Center, USGS

  • Principal investigator and member of the Geochemistry Team in the Yucca Mountain Project Branch, USGS

  • 2001-2004. S.M. Stoller Corporation, Senior Geochemist

  • 1996-2001. Pacific Western Technologies, Ltd. Senior Scientist

  • 1993-1996. US Geological Survey Visiting Research Scientist

  • 1985-1993. Institute of Precambrian Geology and Geochronology (IPGG), St. Petersburg, Russian Academy of Sciences

  • 1971-1985. All Union Geological Research Institute, Leningrad (USSR Ministry of Geology). Engineer (1971-1981) and Junior Research Scientist (1981-1985)

Education and Certifications

  • Ph.D. in Geochemistry, St. Petersburg, Russia

  • MS degree in Radiochemistry, St. Petersburg, Russia

Affiliations and Memberships*

  • American Geophysical Union

  • Geological Society of America

  • International Geochemistry Association

  • Geochemical Society

Science and Products

No Result Found
Filter Total Items: 64

206Pb-230Th-234U-238U and 207Pb-235U geochronology of Quaternary opal, Yucca Mountain, Nevada

U–Th–Pb isotopic systems have been studied in submillimeter-thick outermost layers of Quaternary opal occurring in calcite–silica fracture and cavity coatings within Tertiary tuffs at Yucca Mountain, Nevada, USA. These coatings preserve a record of paleohydrologic conditions at this site, which is being evaluated as a potential high-level nuclear waste repository. The opal precipitated from ground

Vendian age of enderbite from a granulite complex of the Baikal-Muya ophiolite belt, Northern Baikal Region

[No abstract available]

Consequences of slow growth for 230Th/U dating of Quaternary opals, Yucca Mountain, NV, USA

Thermal ionization mass-spectrometry 234U/238U and 230Th/238U data are reported for uranium-rich opals coating fractures and cavities within the silicic tuffs forming Yucca Mountain, NV, the potential site of a high-level radioactive waste repository. High uranium concentrations (up to 207 ppm) and extremely high 230Th/232Th activity ratios (up to about 106) make microsamples of these opals suitab

Constraints on Quaternary unsaturated- and saturated-zone hydrology from geochronological and isotopic studies of calcite and silica, Yucca Mountain, Nevada

No abstracts available.
By
Geosciences and Environmental Change Science Center

Secondary minerals record past percolation flux at Yucca Mountain, Nevada

No abstract available.
By
Geosciences and Environmental Change Science Center

Geochronologic and isotope studies of calcite and silica constraining Quaternary unsaturated- and saturated zone hydrologic flux at Yucca Mountain, Nevada, USA

Both unsaturated- and saturated-zone aqueous solutions are capable of precipitating secondary mineral deposits that document the history and origins of past water flux. Calcite and opal occur as thin coatings on open fractures and cavity floors within the thick unsaturated zone at Yucca Mountain. Outermost surfaces of calcite have 14C ages of between 44,000 and 16,000 radiocarbon years; however, t
By
Geology, Geophysics, and Geochemistry Science Center

U-Pb age evidence for long-term stability of the unsaturated zone at Yucca Mountain

No abstract available.
By
Geosciences and Environmental Change Science Center

Neogene to Quaternary U-Th-Pb geochronology using opal, Yucca Mountain, Nevada, USA

No abstract available.
By
Geology, Geophysics, and Geochemistry Science Center

Anomalous groundwater 234U/238U beneath Yucca Mountain: Evidence for local recharge?

No abstract available.
By
Geosciences and Environmental Change Science Center

Inferences for Yucca Mountain unsaturated-zone hydrology from secondary minerals

No abstract available.
By
Geosciences and Environmental Change Science Center

Anorogenic nature of magmatism in the Northern Baikal volcanic belt: Evidence from geochemical, geochronological (U-Pb), and isotopic (Pb, Nd) data

The Northern Baikal volcanic belt has an age of 1.82-1.87 Ga and extends along the boundary between the Siberian Platform and the Baikal foldbelt. The volcanic belt is composed of volcanics of the Akitkan Group and granitic rocks of the Irel and Primorsk complexes. The geochemistry of the rocks points to the intraplate anorogenic nature of the belt. U-Pb zircon dating of the Chuya granitoids revea

The origin of the 1.73-1.70 Ga anorogenic Ulkan volcano-plutonic complex, Siberian platform, Russia: inferences from geochronological, geochemical and Nd-Sr-Pb isotopic data

The Ulkan volcano-plutonic complex, a part of a 750 km Bilyakchian-Ulkan anorogenic belt, is located in the eastern part of the Archean-Paleoproterozoic Aldan shield. The tectonic position and geochemistry indicate that the Ulkan Complex is a typical A-type or intraplate magmatic association. The felsic volcanics of the Uian Group and granitoids of the North Uchur Massif, the major igneous compone

Non-USGS Publications**

Yu.V. Amelin and L.A. Neymark. 1998, Lead isotope geochemistry of Paleoproterozoic layered intrusions in the eastern Baltic Shield: Inferences about magma sources and U-Th-Pb fractionation in the crust-mantle system. Geochim. Cosmochim. Acta., vol. 62, no. 3, 493-505, https://doi.org/10.1016/S0016-7037(98)00056-8.
E.Yu. Rytsk, L.A. Neimark, Yu.V. Amelin, 1998, Paleozoic granitoids in the Northern Part of the Baikal Orogenic Area: Age and Past Geodynamic Settings. Geotectonics, vol. 32, no. 5, 379-393.
L.A. Neymark, E.Yu. Ritsk, B.M. Gorokhovskiy. 1996. Pb isotope characteristics of some late Riphean Pb-Zn deposits in the folded environs of the Siberian platform. Transactions of the Russian Academy of Sciences. vol.342, no.4, p. 183-187.
L.A. Neimark, A.M. Larin, G.V. Ovchinnikova et al., 1996, U-Pb geochronologic and Pb-isotopic evidence for the Mesozoic mineralization stage of the Archean Stanovoi Megablock, Aldan-Stanovoi Shield. Petrology, vol. 4, no.4, 421-435.
V.A. Vernikovsky, L.A. Neymark, V.A. Ponomarchuk, and S.Z. Yakovleva, 1996, New U-Pb, Sm-Nd, Rb-Sr, and K-Ar ages for the North Taymyr collisional granites and metamorphites: Transactions of the Russian Academy of Sciences. vol. 345a, no.9, 329-334.
R.A. Kumpulainen, J. Mansfeld, K. Sundblad, L. Neymark, and T. Bergman, 1996, Stratigraphy, Age, and Sm-Nd Isotope Systematics of the country rocks to Zn-Pb Sulfide Deposits, Ammeberg District, Sweden: Economic Geology, vol. 91, 1009-1021, https://doi.org/10.2113/gsecongeo.91.6.1009.
L.A. Neimark, E.Yu. Ritsk, G.V. Ovchinnikova et al. 1995. Lead isotopes in gold deposits of the Eastern Sayan (Russia). Geology of Ore Deposits. vol. 37, no. 3, 201-212.
E.V. Khain, L.A. Neymark, Y.V. Amelin, 1995, Isotope-geochronological study of the granites and granite-gneisses of the Gargan Block, Eastern Sayan Range, Siberia, by Pb-Pb and U-Pb method on zircons and Sm-Nd method, Doklady of the Russian Academy of Sciences, vol. 342, no. 5, 776-779 (in Russian).
L.A. Neimark, E.Y. Ritsk, B.M. Gorokhovsky, V.F. Guseva, S.Z. Yakovleva, 1995, Age of Muya granites, Baikal-Vitim ophiolite belt (U-Pb and Sm-Nd isotopic evidence), Doklady of the Russian Academy of Sciences, vol. 343, no. 5, 673-676 (in Russian).
V.A.Vernikovskii, L.A. Neimark, V.A. Ponomarchuk et al. 1995. Geochemistry and age of collision granitoides and metamorphites of the Kara microcontinent (Northern Taimyr). Russian Geology and Geophysics. vol. 36, no.4, 46-60.
V.A. Vernikovsky, A.E. Vernikovskaya, S.M. Lyapunov, L.A. Neimark, V.F. Proskurin, A.I. Chernykh, I.Yu. Safonova, 1994, Petrology, geochemistry, and tectonic setting of plagiogranites of the Chelyuskin ophiolite belt: International Geology Review, vol. 36, no. 10, 961-974.
L.A. Neymark, Yu.V. Amelin, A.M. Larin. 1994. Pb-Sr-Nd isotopic and geochemical constraints on the origin of the 1.54-1.56 Ga Salmi rapakivi-granite -- anorthosite batholith (Karelia, Russia). Mineral. Petrol., vol. 50, no.1-3, 173-193, https://doi.org/10.1007/BF01160146.
S.A. Alekseenko, S.L. Ivlev, and L.A. Neimark, 1994, Standard reference sample of lead isotopic composition: Journal of Analytical Chemistry, vol. 49, no. 12, 1154-1158.
L.A. Neymark, A.A. Nemchin, V.R. Vetrin, E.B. Sal'nikova. 1993. Sm-Nd and Pb-Pb isotope systematics in the lower crust xenoliths from the diatremas in the Southern Kola Peninsula. Transactions of the Russian Academy of Sciences. vol.329, no. 6, 781-784.
I.M. Gorokhov, M.S. Dufour, L.A. Neymark et al. 1993, Early Paleozoic Gondwana fragments in the nappes of the Central Pamirs and Lesser Himalayas: geochemical and isotopic characteristics. Stratigraphy and Geologic Correlation. vol.1, no.3, 250-263.
G.V. Ovchinnikova, L.A. Neymark, O.A. Levchenkov et al. 1993. On the use of the apatite as an U-Pb geochronometer. Stratigraphy and Geological Correlation. vol.1, no.1, 9-19.
L.A. Neymark, E.Yu. Ritsk, N.G. Rizvanova. 1993. Hercynian age and Precambrian crustal protolith of the Barguzin granitoides of the Angar-Vitim batholith : U-Pb and Sm-Nd isotope evidence. Transactions of the Russian Academy of Sciences, vol.332, no.7, 201-206.
L.A. Neymark, V.P. Kovach, A.A. Nemchin et al. 1993. Late Archean intrusive complexes in the Olekma granite-greenstone terrain (Eastern Siberia): geochemical and isotopic study. Prec. Res. vol.62, no.2, 453-472, https://doi.org/10.1016/0301-9268(93)90016-U.
L.A. Neymark, E.Yu. Ritsk, N.G. Rizvanova, B.M. Gorokhovsky. 1993. U-Pb zircon age evidence for a polichronous Angaro-Vitim batholith. Transactions of the Russian Academy of Sciences. vol.333, no.5, 634-637.
V.A. Vernikovsky, L.A. Neymark, V.F. Proskurin, S.Z. Yakovleva. 1993. Late-Riphean age of the Kunar massif plagiogranites (U-Pb zircon dating). Transactions of the Russian Academy of Sciences. vol. 331, no. 6, 706-708.
L.A. Neymark, E.Yu. Ritsk, B.M. Gorokhovsky, Yu.V. Amelin, G.V. Ovchinnikova. 1993. Geochronological and isotope-geochemical study of the gold ore deposits in the Baikal fold area. In: Isotope Dating of Ore Deposits. Moscow, Nauka, p. 124-146 (in Russian).
L.A. Neymark, A.M. Larin, E.Yu. Ritsk, G.V. Ovchinnikova, B.M. Gorokhovsky. 1993. U-Pb geochronological and Pb-isotope evidence of the Hercynian ore-forming event within the Proterozoic frame of the South Siberian Platform. Transactions of the Russian Academy of Sciences. vol.333, no.6, 765-768.
L.A. Neymark, A.M. Larin, G.V. Ovchinnikova, and S.Z. Yakovleva. 1992. U-Pb age of the Dzhugdzhur anorthosites. Transactions of the Russian Academy of Sciences. vol.323A, no.3, 57-62.
L.A. Neymark, A.M. Larin, S.Z.Yakovleva, B.M. Gorokhovsky. 1992. U-Pb age of igneous rocks of the Ulkan graben in the Southeastern part of the Aldan Shield. Transactions of the Russian Academy of Sciences. v.324, no.4, 92-96.
L.A. Neymark, A.A. Nemchin, O.M. Rozen, V.P. Serenko, V.P. Spetsius, I.K. Shuleshko. 1992. Sm-Nd isotope systematics in the lower crust xenoliths from kimberlites of Yakutia. Transactions of the Russian Academy of Sciences. vol.327, no.3, 88-93.
L.A. Neymark, A.M.Larin, S.Z. Yakovleva, N.A. Sryvtsev, and V.V. Buldygerov. 1991. New U-Pb zircon age data on the Akitkan suite, Baikal-Patom fold area. Transactions of the USSR Academy of Sciences. vol. 321, n.8, 197-201.
A.M. Larin, Yu.V.Amelin, and L.A.Neymark. 1991, Age and genesis of the complex scarn ores of the Pitkaranta ore district associated with the Salmi rapakivi massif (Southern Karelia). Geologia Rudnykh Mestorozhdenij (Geology of Ore Deposits), vol. 6, 15-33 (in Russian).
L.A. Neymark, E.Yu. Ritzk, B.M. Gorokhovsky et al., 1991, Lead isotopic composition and genesis of the Pb-Zn mineralization of the Olokit zone of the Northern Baikal region. Geologia Rudnykh Mestorozhdenij (Geology of Ore Deposits), vol. 6, 34-49 (in Russian).
L.K. Levsky and L.A. Neymark. 1991, Isotopic constraints on a prototerrestrial matter. In: The Early Crust : its composition and age. Moscow, Nauka, p. 48-63 (in Russian).
Yu. Amelin, A. Beljaev, A. Larin, L. Neymark, I. Stepanov, 1991. Rapakivi granites and related rocks symposium, July 29-31, 1991, Helsinki, Finland; Salmi batholith and Pitkaranta ore field in Soviet Karelia excursion, August 1-4, 1991 Haapala, Ilmari; Ramo, O Tapani; Salonsaari, Pekka T; GCP, International Geological Correlation Programme Opas - Geologian Tutkimuskeskus, vol.33, 57 pp.
S.A. Sergeyev, Ye.V. Bibikova, O.A. Levchenkov, S.B. Lobach-Zhuchenko, S.Z. Yakovleva, G.V. Ovchinnikova, L. A. Neymark, A.N. Komarov, B.M. Gorokhovskiy, 1990. Isotope geochronology of the Vodlozerskiy gneiss complex, Geokhimiya, vol.1990, no.1, 73-83. (in Russian).
G.V. Ovchinnikova, S.B. Lobach-Zhuchenko, S.A. Sergeyev, S.Z. Yakovleva, O.A. Levchenkov, L.A. Neymark, A.N. Komarov, B.M. Gorokhovskiy, A.M. Fedoseyenko, I.N. Krylov, 1990. Geochronology and petrology of the late kinematic granites of southeastern Karelia based on geochemical and isotopic data. Geokhimiya, vol.1990, no.11, 1561-1573 (in Russian).
V.L. Dook, L.A. Neymark, and V.A. Rudnik (Eds.). 1989. The Oldest Rocks of the Aldan-Stanovik Shield, Eastern Siberia, USSR. IGCP Project 280 “The Oldest Rocks on Earth”, Excursion guide, Leningrad-Mainz, 121 p.
Yu.V. Amelin, L.A. Neymark, D.I. Matukov et al. 1988. Analytical parameters and operation experience of MI1320-PRM2 mass-spectrometers . In: Isotopic methods in geology, geochemistry and metallogeny. Leningrad, Nauka, p.102-116. (in Russian).
L.A. Neymark, G.V. Ovchinnikova, B.M. Gorokhovsky et al. 1988. Pb isotopes in sulfides from rocks of the Sumozero--Kenozero greenstone belt. In: Isotopic methods in geology, geochemistry and metallogeny. Leningrad, Nauka. p. 42-48. (in Russian).
L.A. Neymark, A.B. Kotov, D.P. Vinogradov et al. 1988. Age and occurrence of early folded and post-folded granitoids of northwestern Lake Ladoga region according to data of Pb, O isotopes. In: Isotopic methods in geology, geochemistry and metallogeny. Leningrad, Nauka p. 21-41. (in Russian).
L.A. Neymark, S.L. Mirkina, A.G. Rublev et al. 1987. Isotope age of the granites in the Irelsky Complex, Baikal Region. Izvestiya Akademii Nauk SSSR. vol. 5, 18-25 (in Russian).
A.G. Rublev, G.A. Murina, A.P. Chukhonin, L.A. Neimark, et al. 1987. Geochronology of early-Proterozoic granitoid magmatism in the Kodar-Udokan Zone. Soviet Geology and Geophysics, vol. 28, no.6, 26-33, 1987 (in Russian).
L.A. Neymark. 1987. Potential and restrictions of the lead-isochron method in dating Precambrian polymetamorphic rocks. In: Isotopic dating of metamorphic and metasomatic process. Shukoljukov Yu.A. (Ed.). Moscow, Nauka, p. 29-44 (in Russian).
L.A Neymark. 1987. The application of U-Pb to the geochronological studies of Precambrian metallic ore deposits. In: Gorokhov I.M., Levchenkov O.A. (Editors) Isotopic methods on Geochronology. Leningrad, Nauka, p.29-44 (in Russian).
L.A. Neymark. 1986 U-Pb isotopic constraints on the age and primordial materials of the Earth. In: Isotope methods in geochemistry and cosmochemistry. L.K.Levsky (Ed.) Leningrad, Nauka, p. 3-21 (in Russian).
L.A. Neymark, A.D. Iskanderova, E.P. Miron'uk et al. 1984. U-Pb age of the Charskoje ore deposit of BIF, Eastern Siberia. Doklady Akademii Nauk SSSR. vol. 234. 1246-1249. (in Russian).
L.A. Neymark. 1983. Quantitative models for the evolution of the crust-mantle system utilizing Pb isotope data. In: Geochemistry of radiogenic isotopes in the early stages of the Earth's evolution. Shukol’ukov J.A. (Ed.), Moscow, Nauka, p.151-167 (in Russian).
G.V. Ovchinnikova, L.A. Neymark. 1981. The excess lead in meteorites. Geochemistry International. vol.18, no.4, 102-115.
L.A. Neymark, A.D. Iskanderova, A.P. Chukhonin, et al. 1981. U-Pb data on the Archean age of metamorphic rocks of the Stanovoy Range: Geochemistry International, vol.18, no.5, 55-64.
L.A. Neymark, O.A. Levchenkov. 1979. A method of age calculation for open U-Pb isotope systems. Geochemistry International. vol.16, no.3, 34-39.
S.L. Mirkina, L.A.Neymark, B.B. Golubev, I.G. Smyslova. 1976. Radiologic dating of Neogene-Quaternary uranium minerals by Pb-isotope method. Geokhimia, no. 9, 43-48 (in Russian).

**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.

Science and Products

  • Science
  • Data
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  • Publications
    Filter Total Items: 64

    206Pb-230Th-234U-238U and 207Pb-235U geochronology of Quaternary opal, Yucca Mountain, Nevada

    U–Th–Pb isotopic systems have been studied in submillimeter-thick outermost layers of Quaternary opal occurring in calcite–silica fracture and cavity coatings within Tertiary tuffs at Yucca Mountain, Nevada, USA. These coatings preserve a record of paleohydrologic conditions at this site, which is being evaluated as a potential high-level nuclear waste repository. The opal precipitated from ground

    Vendian age of enderbite from a granulite complex of the Baikal-Muya ophiolite belt, Northern Baikal Region

    [No abstract available]

    Consequences of slow growth for 230Th/U dating of Quaternary opals, Yucca Mountain, NV, USA

    Thermal ionization mass-spectrometry 234U/238U and 230Th/238U data are reported for uranium-rich opals coating fractures and cavities within the silicic tuffs forming Yucca Mountain, NV, the potential site of a high-level radioactive waste repository. High uranium concentrations (up to 207 ppm) and extremely high 230Th/232Th activity ratios (up to about 106) make microsamples of these opals suitab

    Constraints on Quaternary unsaturated- and saturated-zone hydrology from geochronological and isotopic studies of calcite and silica, Yucca Mountain, Nevada

    No abstracts available.
    By
    Geosciences and Environmental Change Science Center

    Secondary minerals record past percolation flux at Yucca Mountain, Nevada

    No abstract available.
    By
    Geosciences and Environmental Change Science Center

    Geochronologic and isotope studies of calcite and silica constraining Quaternary unsaturated- and saturated zone hydrologic flux at Yucca Mountain, Nevada, USA

    Both unsaturated- and saturated-zone aqueous solutions are capable of precipitating secondary mineral deposits that document the history and origins of past water flux. Calcite and opal occur as thin coatings on open fractures and cavity floors within the thick unsaturated zone at Yucca Mountain. Outermost surfaces of calcite have 14C ages of between 44,000 and 16,000 radiocarbon years; however, t
    By
    Geology, Geophysics, and Geochemistry Science Center

    U-Pb age evidence for long-term stability of the unsaturated zone at Yucca Mountain

    No abstract available.
    By
    Geosciences and Environmental Change Science Center

    Neogene to Quaternary U-Th-Pb geochronology using opal, Yucca Mountain, Nevada, USA

    No abstract available.
    By
    Geology, Geophysics, and Geochemistry Science Center

    Anomalous groundwater 234U/238U beneath Yucca Mountain: Evidence for local recharge?

    No abstract available.
    By
    Geosciences and Environmental Change Science Center

    Inferences for Yucca Mountain unsaturated-zone hydrology from secondary minerals

    No abstract available.
    By
    Geosciences and Environmental Change Science Center

    Anorogenic nature of magmatism in the Northern Baikal volcanic belt: Evidence from geochemical, geochronological (U-Pb), and isotopic (Pb, Nd) data

    The Northern Baikal volcanic belt has an age of 1.82-1.87 Ga and extends along the boundary between the Siberian Platform and the Baikal foldbelt. The volcanic belt is composed of volcanics of the Akitkan Group and granitic rocks of the Irel and Primorsk complexes. The geochemistry of the rocks points to the intraplate anorogenic nature of the belt. U-Pb zircon dating of the Chuya granitoids revea

    The origin of the 1.73-1.70 Ga anorogenic Ulkan volcano-plutonic complex, Siberian platform, Russia: inferences from geochronological, geochemical and Nd-Sr-Pb isotopic data

    The Ulkan volcano-plutonic complex, a part of a 750 km Bilyakchian-Ulkan anorogenic belt, is located in the eastern part of the Archean-Paleoproterozoic Aldan shield. The tectonic position and geochemistry indicate that the Ulkan Complex is a typical A-type or intraplate magmatic association. The felsic volcanics of the Uian Group and granitoids of the North Uchur Massif, the major igneous compone

    Non-USGS Publications**

    Yu.V. Amelin and L.A. Neymark. 1998, Lead isotope geochemistry of Paleoproterozoic layered intrusions in the eastern Baltic Shield: Inferences about magma sources and U-Th-Pb fractionation in the crust-mantle system. Geochim. Cosmochim. Acta., vol. 62, no. 3, 493-505, https://doi.org/10.1016/S0016-7037(98)00056-8.
    E.Yu. Rytsk, L.A. Neimark, Yu.V. Amelin, 1998, Paleozoic granitoids in the Northern Part of the Baikal Orogenic Area: Age and Past Geodynamic Settings. Geotectonics, vol. 32, no. 5, 379-393.
    L.A. Neymark, E.Yu. Ritsk, B.M. Gorokhovskiy. 1996. Pb isotope characteristics of some late Riphean Pb-Zn deposits in the folded environs of the Siberian platform. Transactions of the Russian Academy of Sciences. vol.342, no.4, p. 183-187.
    L.A. Neimark, A.M. Larin, G.V. Ovchinnikova et al., 1996, U-Pb geochronologic and Pb-isotopic evidence for the Mesozoic mineralization stage of the Archean Stanovoi Megablock, Aldan-Stanovoi Shield. Petrology, vol. 4, no.4, 421-435.
    V.A. Vernikovsky, L.A. Neymark, V.A. Ponomarchuk, and S.Z. Yakovleva, 1996, New U-Pb, Sm-Nd, Rb-Sr, and K-Ar ages for the North Taymyr collisional granites and metamorphites: Transactions of the Russian Academy of Sciences. vol. 345a, no.9, 329-334.
    R.A. Kumpulainen, J. Mansfeld, K. Sundblad, L. Neymark, and T. Bergman, 1996, Stratigraphy, Age, and Sm-Nd Isotope Systematics of the country rocks to Zn-Pb Sulfide Deposits, Ammeberg District, Sweden: Economic Geology, vol. 91, 1009-1021, https://doi.org/10.2113/gsecongeo.91.6.1009.
    L.A. Neimark, E.Yu. Ritsk, G.V. Ovchinnikova et al. 1995. Lead isotopes in gold deposits of the Eastern Sayan (Russia). Geology of Ore Deposits. vol. 37, no. 3, 201-212.
    E.V. Khain, L.A. Neymark, Y.V. Amelin, 1995, Isotope-geochronological study of the granites and granite-gneisses of the Gargan Block, Eastern Sayan Range, Siberia, by Pb-Pb and U-Pb method on zircons and Sm-Nd method, Doklady of the Russian Academy of Sciences, vol. 342, no. 5, 776-779 (in Russian).
    L.A. Neimark, E.Y. Ritsk, B.M. Gorokhovsky, V.F. Guseva, S.Z. Yakovleva, 1995, Age of Muya granites, Baikal-Vitim ophiolite belt (U-Pb and Sm-Nd isotopic evidence), Doklady of the Russian Academy of Sciences, vol. 343, no. 5, 673-676 (in Russian).
    V.A.Vernikovskii, L.A. Neimark, V.A. Ponomarchuk et al. 1995. Geochemistry and age of collision granitoides and metamorphites of the Kara microcontinent (Northern Taimyr). Russian Geology and Geophysics. vol. 36, no.4, 46-60.
    V.A. Vernikovsky, A.E. Vernikovskaya, S.M. Lyapunov, L.A. Neimark, V.F. Proskurin, A.I. Chernykh, I.Yu. Safonova, 1994, Petrology, geochemistry, and tectonic setting of plagiogranites of the Chelyuskin ophiolite belt: International Geology Review, vol. 36, no. 10, 961-974.
    L.A. Neymark, Yu.V. Amelin, A.M. Larin. 1994. Pb-Sr-Nd isotopic and geochemical constraints on the origin of the 1.54-1.56 Ga Salmi rapakivi-granite -- anorthosite batholith (Karelia, Russia). Mineral. Petrol., vol. 50, no.1-3, 173-193, https://doi.org/10.1007/BF01160146.
    S.A. Alekseenko, S.L. Ivlev, and L.A. Neimark, 1994, Standard reference sample of lead isotopic composition: Journal of Analytical Chemistry, vol. 49, no. 12, 1154-1158.
    L.A. Neymark, A.A. Nemchin, V.R. Vetrin, E.B. Sal'nikova. 1993. Sm-Nd and Pb-Pb isotope systematics in the lower crust xenoliths from the diatremas in the Southern Kola Peninsula. Transactions of the Russian Academy of Sciences. vol.329, no. 6, 781-784.
    I.M. Gorokhov, M.S. Dufour, L.A. Neymark et al. 1993, Early Paleozoic Gondwana fragments in the nappes of the Central Pamirs and Lesser Himalayas: geochemical and isotopic characteristics. Stratigraphy and Geologic Correlation. vol.1, no.3, 250-263.
    G.V. Ovchinnikova, L.A. Neymark, O.A. Levchenkov et al. 1993. On the use of the apatite as an U-Pb geochronometer. Stratigraphy and Geological Correlation. vol.1, no.1, 9-19.
    L.A. Neymark, E.Yu. Ritsk, N.G. Rizvanova. 1993. Hercynian age and Precambrian crustal protolith of the Barguzin granitoides of the Angar-Vitim batholith : U-Pb and Sm-Nd isotope evidence. Transactions of the Russian Academy of Sciences, vol.332, no.7, 201-206.
    L.A. Neymark, V.P. Kovach, A.A. Nemchin et al. 1993. Late Archean intrusive complexes in the Olekma granite-greenstone terrain (Eastern Siberia): geochemical and isotopic study. Prec. Res. vol.62, no.2, 453-472, https://doi.org/10.1016/0301-9268(93)90016-U.
    L.A. Neymark, E.Yu. Ritsk, N.G. Rizvanova, B.M. Gorokhovsky. 1993. U-Pb zircon age evidence for a polichronous Angaro-Vitim batholith. Transactions of the Russian Academy of Sciences. vol.333, no.5, 634-637.
    V.A. Vernikovsky, L.A. Neymark, V.F. Proskurin, S.Z. Yakovleva. 1993. Late-Riphean age of the Kunar massif plagiogranites (U-Pb zircon dating). Transactions of the Russian Academy of Sciences. vol. 331, no. 6, 706-708.
    L.A. Neymark, E.Yu. Ritsk, B.M. Gorokhovsky, Yu.V. Amelin, G.V. Ovchinnikova. 1993. Geochronological and isotope-geochemical study of the gold ore deposits in the Baikal fold area. In: Isotope Dating of Ore Deposits. Moscow, Nauka, p. 124-146 (in Russian).
    L.A. Neymark, A.M. Larin, E.Yu. Ritsk, G.V. Ovchinnikova, B.M. Gorokhovsky. 1993. U-Pb geochronological and Pb-isotope evidence of the Hercynian ore-forming event within the Proterozoic frame of the South Siberian Platform. Transactions of the Russian Academy of Sciences. vol.333, no.6, 765-768.
    L.A. Neymark, A.M. Larin, G.V. Ovchinnikova, and S.Z. Yakovleva. 1992. U-Pb age of the Dzhugdzhur anorthosites. Transactions of the Russian Academy of Sciences. vol.323A, no.3, 57-62.
    L.A. Neymark, A.M. Larin, S.Z.Yakovleva, B.M. Gorokhovsky. 1992. U-Pb age of igneous rocks of the Ulkan graben in the Southeastern part of the Aldan Shield. Transactions of the Russian Academy of Sciences. v.324, no.4, 92-96.
    L.A. Neymark, A.A. Nemchin, O.M. Rozen, V.P. Serenko, V.P. Spetsius, I.K. Shuleshko. 1992. Sm-Nd isotope systematics in the lower crust xenoliths from kimberlites of Yakutia. Transactions of the Russian Academy of Sciences. vol.327, no.3, 88-93.
    L.A. Neymark, A.M.Larin, S.Z. Yakovleva, N.A. Sryvtsev, and V.V. Buldygerov. 1991. New U-Pb zircon age data on the Akitkan suite, Baikal-Patom fold area. Transactions of the USSR Academy of Sciences. vol. 321, n.8, 197-201.
    A.M. Larin, Yu.V.Amelin, and L.A.Neymark. 1991, Age and genesis of the complex scarn ores of the Pitkaranta ore district associated with the Salmi rapakivi massif (Southern Karelia). Geologia Rudnykh Mestorozhdenij (Geology of Ore Deposits), vol. 6, 15-33 (in Russian).
    L.A. Neymark, E.Yu. Ritzk, B.M. Gorokhovsky et al., 1991, Lead isotopic composition and genesis of the Pb-Zn mineralization of the Olokit zone of the Northern Baikal region. Geologia Rudnykh Mestorozhdenij (Geology of Ore Deposits), vol. 6, 34-49 (in Russian).
    L.K. Levsky and L.A. Neymark. 1991, Isotopic constraints on a prototerrestrial matter. In: The Early Crust : its composition and age. Moscow, Nauka, p. 48-63 (in Russian).
    Yu. Amelin, A. Beljaev, A. Larin, L. Neymark, I. Stepanov, 1991. Rapakivi granites and related rocks symposium, July 29-31, 1991, Helsinki, Finland; Salmi batholith and Pitkaranta ore field in Soviet Karelia excursion, August 1-4, 1991 Haapala, Ilmari; Ramo, O Tapani; Salonsaari, Pekka T; GCP, International Geological Correlation Programme Opas - Geologian Tutkimuskeskus, vol.33, 57 pp.
    S.A. Sergeyev, Ye.V. Bibikova, O.A. Levchenkov, S.B. Lobach-Zhuchenko, S.Z. Yakovleva, G.V. Ovchinnikova, L. A. Neymark, A.N. Komarov, B.M. Gorokhovskiy, 1990. Isotope geochronology of the Vodlozerskiy gneiss complex, Geokhimiya, vol.1990, no.1, 73-83. (in Russian).
    G.V. Ovchinnikova, S.B. Lobach-Zhuchenko, S.A. Sergeyev, S.Z. Yakovleva, O.A. Levchenkov, L.A. Neymark, A.N. Komarov, B.M. Gorokhovskiy, A.M. Fedoseyenko, I.N. Krylov, 1990. Geochronology and petrology of the late kinematic granites of southeastern Karelia based on geochemical and isotopic data. Geokhimiya, vol.1990, no.11, 1561-1573 (in Russian).
    V.L. Dook, L.A. Neymark, and V.A. Rudnik (Eds.). 1989. The Oldest Rocks of the Aldan-Stanovik Shield, Eastern Siberia, USSR. IGCP Project 280 “The Oldest Rocks on Earth”, Excursion guide, Leningrad-Mainz, 121 p.
    Yu.V. Amelin, L.A. Neymark, D.I. Matukov et al. 1988. Analytical parameters and operation experience of MI1320-PRM2 mass-spectrometers . In: Isotopic methods in geology, geochemistry and metallogeny. Leningrad, Nauka, p.102-116. (in Russian).
    L.A. Neymark, G.V. Ovchinnikova, B.M. Gorokhovsky et al. 1988. Pb isotopes in sulfides from rocks of the Sumozero--Kenozero greenstone belt. In: Isotopic methods in geology, geochemistry and metallogeny. Leningrad, Nauka. p. 42-48. (in Russian).
    L.A. Neymark, A.B. Kotov, D.P. Vinogradov et al. 1988. Age and occurrence of early folded and post-folded granitoids of northwestern Lake Ladoga region according to data of Pb, O isotopes. In: Isotopic methods in geology, geochemistry and metallogeny. Leningrad, Nauka p. 21-41. (in Russian).
    L.A. Neymark, S.L. Mirkina, A.G. Rublev et al. 1987. Isotope age of the granites in the Irelsky Complex, Baikal Region. Izvestiya Akademii Nauk SSSR. vol. 5, 18-25 (in Russian).
    A.G. Rublev, G.A. Murina, A.P. Chukhonin, L.A. Neimark, et al. 1987. Geochronology of early-Proterozoic granitoid magmatism in the Kodar-Udokan Zone. Soviet Geology and Geophysics, vol. 28, no.6, 26-33, 1987 (in Russian).
    L.A. Neymark. 1987. Potential and restrictions of the lead-isochron method in dating Precambrian polymetamorphic rocks. In: Isotopic dating of metamorphic and metasomatic process. Shukoljukov Yu.A. (Ed.). Moscow, Nauka, p. 29-44 (in Russian).
    L.A Neymark. 1987. The application of U-Pb to the geochronological studies of Precambrian metallic ore deposits. In: Gorokhov I.M., Levchenkov O.A. (Editors) Isotopic methods on Geochronology. Leningrad, Nauka, p.29-44 (in Russian).
    L.A. Neymark. 1986 U-Pb isotopic constraints on the age and primordial materials of the Earth. In: Isotope methods in geochemistry and cosmochemistry. L.K.Levsky (Ed.) Leningrad, Nauka, p. 3-21 (in Russian).
    L.A. Neymark, A.D. Iskanderova, E.P. Miron'uk et al. 1984. U-Pb age of the Charskoje ore deposit of BIF, Eastern Siberia. Doklady Akademii Nauk SSSR. vol. 234. 1246-1249. (in Russian).
    L.A. Neymark. 1983. Quantitative models for the evolution of the crust-mantle system utilizing Pb isotope data. In: Geochemistry of radiogenic isotopes in the early stages of the Earth's evolution. Shukol’ukov J.A. (Ed.), Moscow, Nauka, p.151-167 (in Russian).
    G.V. Ovchinnikova, L.A. Neymark. 1981. The excess lead in meteorites. Geochemistry International. vol.18, no.4, 102-115.
    L.A. Neymark, A.D. Iskanderova, A.P. Chukhonin, et al. 1981. U-Pb data on the Archean age of metamorphic rocks of the Stanovoy Range: Geochemistry International, vol.18, no.5, 55-64.
    L.A. Neymark, O.A. Levchenkov. 1979. A method of age calculation for open U-Pb isotope systems. Geochemistry International. vol.16, no.3, 34-39.
    S.L. Mirkina, L.A.Neymark, B.B. Golubev, I.G. Smyslova. 1976. Radiologic dating of Neogene-Quaternary uranium minerals by Pb-isotope method. Geokhimia, no. 9, 43-48 (in Russian).

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