U-Pb (LA-ICP-MS) dating of detrital zircons from clastic sediments composing lowest part of Precambrian sequence of Northern Timan

The article presents the first U-Pb data on the age of detrital zircons from clastic sediments of Rumyanichnaya Formation included in Barma Group which constitutes the lowest outcropped part of the Precambrian sequence of the Northern Timan. Age data (LA-ICP-MS) for 94 zircon grains from fine-grained aleuritic sandstone cover the range of 981–2582 Ma. Weighted average age of the two youngest zircons yields the age of 983±40 Ma which provides grounds to assume that sediment deposition took place in Late Riphean (Neoproterozoic). The accumulation of clastic sediments that compose the all three formations of Barma Group (~5 km thick) was controlled mostly with terrigenous material from eroded rock complexes coeval with crystalline complexes of Fennoscandia and Central Russian Belt.

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U-Pb (LA-ICP-MS) dating of detrital zircons from clastic sediments of upper part of Precambrian basement of Northern Timan

Bulletin of Moscow Society of Naturalists. Geological Series ◽

10.19110/0366-1318-2017-1-10-20 ◽

2017 ◽

Vol 92 (1) ◽

Author(s):

V. L. Andreichev ◽

◽

A. A. Soboleva ◽

J. K. Hourigan ◽

◽

...

Keyword(s):

Weighted Average ◽

Sediment Deposition ◽

Detrital Zircons ◽

Precambrian Basement ◽

Terrigenous Material ◽

Clastic Sediments ◽

Icp Ms ◽

Crystalline Complexes Of

The article presents the first U–Pb data on the age of detrital zircons from clastic sediments of Yambozero Formation (Barmin Group) which constitutes the upper part of the Precambrian sequence of the Northern Timan. Age data for 80 zircon grains (LA-ICP-MS) cover the range of 989–2713 Ma. Weighted average age of the three youngest zircons yields the age of 1004±15 Ma which provides grounds to assume that sediment deposition took place in late Riphean (Neoproterozoic). The accumulation of clastic sediments of Yambozero Formation was controlled mostly with terrigenous material from eroded rock complexes coeval with crystalline complexes of Fennoscandia and Central Russian Belt.

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Sedimentary provenance of Mid-Devonian clastic sediments in the Teplá-Barrandian Unit (Bohemian Massif): U–Pb and Pb–Pb geochronology of detrital zircons by laser ablation ICP-MS

Mineralogy and Petrology ◽

10.1007/s00710-004-0057-1 ◽

2005 ◽

Vol 84 (1-2) ◽

pp. 47-68 ◽

Cited By ~ 34

Author(s):

L. Strnad ◽

M. Mihaljevič

Keyword(s):

Laser Ablation ◽

Bohemian Massif ◽

Detrital Zircons ◽

Sedimentary Provenance ◽

Clastic Sediments ◽

Icp Ms

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Lithogeochemical characteristics of metasandstones of the Chetlas series (Chetlassky Kamen, Middle Timan)

Vestnik of Geosciences ◽

10.19110/geov.2021.7.1 ◽

2021 ◽

pp. 3-12

Author(s):

N. Y. Nikulova ◽

◽

O. V. Udoratina ◽

I. V. Kozyreva

Keyword(s):

Inductively Coupled Plasma ◽

Volcanic Rocks ◽

Rare Metal ◽

Weathering Crust ◽

Terrigenous Material ◽

Inductively Coupled ◽

Coastal Marine ◽

Icp Ms ◽

Middle Timan ◽

Destruction Of Rocks

The lithological and geochemical features of the metasandstones of the Svetlinskaya and Vizingskaya formations of the Middle Late Riphean Chetlas series in the Middle Timan, which are a substrate of rare-metal-rare-earth mineralization in several ore occurrences of the Kosyus ore cluster, have been investigated. The interpretation of the results of traditional weight chemical and mass spectrometric inductively coupled plasma (ICP MS) analyses allowed us to identify differences in the material composition of metapesanics, mainly due to changes in the degree of sedimentation maturity of terrigenous material coming from the demolition areas. The composition of metasandstones in various ratios includes both weakly weathered products of destruction of volcanic rocks of intermediate/basic composition, and altered, including under conditions of the weathering crust, metaterrigenous formations. The accumulation of sediments took place in a shallow coastal-marine environment with changing hydrodynamics, which affected the rate of destruction of rocks in paleo-catchments.

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LA-ICP-MS U–Pb geochronology of detrital zircons from the Zhaochigou Formation-complex in the Helan Mountain and its tectonic significance

Chinese Science Bulletin ◽

10.1007/s11434-014-0180-2 ◽

2014 ◽

Vol 59 (13) ◽

pp. 1425-1437 ◽

Cited By ~ 3

Author(s):

Liming Li ◽

Zuoxun Zeng ◽

Yanjun Lu ◽

Yunxu Wei ◽

Shimin Xiang ◽

...

Keyword(s):

Detrital Zircons ◽

Icp Ms ◽

Tectonic Significance ◽

Helan Mountain

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Supplemental Material: Detrital zircons from Late Paleozoic Ice Age sequences in Victoria Land (Antarctica): New constraints on the glaciation of southern Gondwana

10.1130/gsab.s.14251163.v1 ◽

2021 ◽

Author(s):

Luca Zurli ◽

Gianluca Cornamusini

Keyword(s):

Inductively Coupled Plasma ◽

Detrital Zircons ◽

Ice Age ◽

Late Paleozoic ◽

Inductively Coupled ◽

Victoria Land ◽

Icp Ms ◽

Late Paleozoic Ice Age ◽

Plasma Mass Spectrometry ◽

Shape Characterization

Raw laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) analysis and detrital zircon grain shape characterization of the late Paleozoic diamictite samples from Victoria Land, Antarctica.

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The type section of the Codell Sandstone

10.31582/rmag.mg.58.3.211 ◽

2021 ◽

Vol 58 (3) ◽

pp. 211-248

Author(s):

James Hagadorn ◽

Mark Longman ◽

Richard Bottjer ◽

Virginia Gent ◽

Christopher Holm-Denoma ◽

...

Keyword(s):

Surface Expression ◽

Potassium Feldspar ◽

Detrital Zircons ◽

Niobrara Formation ◽

Denver Basin ◽

Fine Grained ◽

Type Section ◽

Fossil Fish ◽

Fish Teeth ◽

Reference Section

We formally assign, describe and interpret a principal reference section for the middle Turonian Codell Sandstone Member of the Carlile Shale near Codell, Kansas. This section, at the informally named Pumpjack Road, provides the thickest surface expression (9 m, ~30 ft) of the unit in Ellis County. The outcrop exposes features that typify the Codell throughout the southern Denver Basin and vicinity. At this reference section, the Codell conformably overlies the Blue Hill Shale Member of the Carlile Shale and is unconformably overlain by the Fort Hays Limestone Member of the Niobrara Formation or locally by a thin (<0.9 m, <3 ft) discontinuous mudstone known as the Antonino facies. The top contact of the Codell is slightly undulatory with possible compaction features or narrow (<30.5 m, <100 ft), low-relief (0.3-0.6 m, 1-2 ft) scours, all of which hint that the Codell is a depositional remnant, even at the type section. At Pumpjack Road, the Codell coarsens upward from a recessive-weathering argillaceous medium-grained siltstone with interbedded mudstone at its base to a more indurated cliff-forming muddy, highly bioturbated, very fine-grained sandstone at its top. The unit contains three informal gradational packages: a lower Codell of medium to coarse siltstone and mudstone, a middle Codell of muddy coarse siltstone, and an upper muddy Codell dominated by well-sorted very fine-grained sandstone. The largest grain fractions, all <120 mm in size, are mostly quartz (40-80%), potassium feldspar (7-12%), and albite (1-2%), with some chert (<15%), zircon, and other constituents such as abraded phosphatic skeletal debris. Rare fossil fish teeth and bones also occur. Detrital and authigenic clays make up 9 to 42% of the Codell at the reference section. Detrital illite and mixed layer illite/smectite are common, along with omnipresent kaolinite as grain coatings or cement. As is typical for the Codell, the sandstone at the type section has been pervasively bioturbated. Most primary structures and bedding are obscured, particularly toward the top of the unit where burrows are larger, deeper and more diverse than at its base. This bioturbation has created a textural inversion in which the larger silt and sand grains are very well sorted but are mixed with mud. Detrital zircons from the upper Codell are unusual in that they are mostly prismatic to acicular, euhedral, colorless, unpitted, and unabraded, and have a near-unimodal age peak centered at ~94 Ma. These characteristics suggest they were reworked mainly from Cenomanian bentonites; their ultimate source was likely from the Cordilleran orogenic belt to the west and northwest.

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The Giant Chalukou Porphyry Mo Deposit, Northeast China: The Product of a Short-Lived, High Flux Mineralizing Event

Economic Geology ◽

10.5382/econgeo.4818 ◽

2021 ◽

Author(s):

Qingqing Zhao ◽

Degao Zhai ◽

Ryan Mathur ◽

Jiajun Liu ◽

David Selby ◽

...

Keyword(s):

High Precision ◽

Inductively Coupled Plasma ◽

Hydrothermal Activity ◽

Ore Deposits ◽

Ionization Mass ◽

Inductively Coupled ◽

Fine Grained ◽

Porphyry Cu ◽

Icp Ms ◽

Porphyry Mo Deposit

Abstract Whether giant porphyry ore deposits are the products of single, short-lived magmatic-hydrothermal events or multiple events over a prolonged interval is a topic of considerable debate. Previous studies, however, have all been devoted to porphyry Cu and Cu-Mo deposits. In this paper, we report high-precision isotope dilution-negative-thermal ionization mass spectrometric (ID-N-TIMS) molybdenite Re-Os ages for the newly discovered, world-class Chalukou porphyry Mo deposit (reserves of 2.46 Mt @ 0.087 wt % Mo) in NE China. Samples were selected based on a careful evaluation of the relative timing of the different vein types (i.e., A, B, and D veins), thereby ensuring that the suite of samples analyzed could be used to reliably determine the age and duration of mineralization. The molybdenite Re-Os geochronology reveals that hydrothermal activity at Chalukou involved two magmatic-hydrothermal events spanning an interval of 6.92 ± 0.16 m.y. The first event (153.96 ± 0.08/0.63/0.79 Ma, molybdenite ID-N-TIMS Re-Os age) was associated with the emplacement of a granite porphyry dated at 152.1 ± 2.2 Ma (zircon laser ablation-inductively coupled plasma-microscopic [LA-ICP-MS] U-Pb ages), and led to only minor Mo mineralization, accounting for <10% of the overall Mo budget. The bulk of the Mo (>90%) was deposited in less than 650 kyr, between 147.67 ± 0.10/0.60/0.76 and 147.04 ± 0.12/0.72/0.86 Ma (molybdenite ID-N-TIMS Re-Os ages), coincident with the emplacement of a fine-grained porphyry at 148.1 ± 2.6 Ma (zircon LA-ICP-MS U-Pb ages). The high-precision Re-Os age determinations presented here show, contrary to the finding of a number of studies of porphyry Cu and Cu-Mo systems, that the giant Chalukou porphyry Mo deposit primarily formed in a single, short-lived (<650 kyr) hydrothermal event, suggesting that this may also have been the case for other giant porphyry Mo deposits.

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Pyrite Varieties at Pobeda Hydrothermal Fields, Mid-Atlantic Ridge 17°07′–17°08′ N: LA-ICP-MS Data Deciphering

Minerals ◽

10.3390/min10070622 ◽

2020 ◽

Vol 10 (7) ◽

pp. 622

Author(s):

Valeriy Maslennikov ◽

Georgy Cherkashov ◽

Dmitry Artemyev ◽

Anna Firstova ◽

Ross Large ◽

...

Keyword(s):

Low Temperature ◽

Massive Sulfide ◽

Black Smoker ◽

Fine Grained ◽

Framboidal Pyrite ◽

Icp Ms ◽

Mid Atlantic Ridge ◽

Seafloor Massive Sulfide ◽

Hydrothermal Fields ◽

Feeder Zone

The massive sulfide ores of the Pobeda hydrothermal fields are grouped into five main mineral microfacies: (1) isocubanite-pyrite, (2) pyrite-wurtzite-isocubanite, (3) pyrite with minor isocubanite and wurtzite-sphalerite microinclusions, (4) pyrite-rich with framboidal pyrite, and (5) marcasite-pyrite. This sequence reflects the transition from feeder zone facies to seafloor diffuser facies. Spongy, framboidal, and fine-grained pyrite varieties replaced pyrrhotite, greigite, and mackinawite “precursors”. The later coarse and fine banding oscillatory-zoned pyrite and marcasite crystals are overgrown or replaced by unzoned subhedral and euhedral pyrite. In the microfacies range, the amount of isocubanite, wurtzite, unzoned euhedral pyrite decreases versus an increasing portion of framboidal, fine-grained, and spongy pyrite and also marcasite and its colloform and radial varieties. The trace element characteristics of massive sulfides of Pobeda seafloor massive sulfide (SMS) deposit are subdivided into four associations: (1) high temperature—Cu, Se, Te, Bi, Co, and Ni; (2) mid temperature—Zn, As, Sb, and Sn; (3) low temperature—Pb, Sb, Ag, Bi, Au, Tl, and Mn; and (4) seawater—U, V, Mo, and Ni. The high contents of Cu, Co, Se, Bi, Te, and values of Co/Ni ratios decrease in the range from unzoned euhedral pyrite to oscillatory-zoned and framboidal pyrite, as well as to colloform and crystalline marcasite. The trend of Co/Ni values indicates a change from hydrothermal to hydrothermal-diagenetic crystallization of the pyrite. The concentrations of Zn, As, Sb, Pb, Ag, and Tl, as commonly observed in pyrite formed from mid- and low-temperature fluids, decline with increasing crystal size of pyrite and marcasite. Coarse oscillatory-zoned pyrite crystals contain elevated Mn compared to unzoned euhedral varieties. Framboidal pyrite hosts maximum concentrations of Mo, U, and V probably derived from ocean water mixed with hydrothermal fluids. In the Pobeda SMS deposit, the position of microfacies changes from the black smoker feeder zone at the base of the ore body, to seafloor marcasite-pyrite from diffuser fragments in sulfide breccias. We suggest that the temperatures of mineralization decreased in the same direction and determined the zonal character of deposit.

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