共查询到20条相似文献,搜索用时 12 毫秒
1.
I. D. Sobolev A. N. Shadrin V. A. Rastorguev D. A. Kozyreva 《Moscow University Geology Bulletin》2017,72(2):115-125
Granitoids of the Rechnoy and Yalya-Pe paleovolcanoes, which were ascribed to the Silurian Khoimpe complex during a geological mapping, and granitoids of the Nganotsky-1 and Nganotsky-2 plutons that were ascribed to the Early Devonian Yunyaga complex were studied in the Shchuchinskaya zone of the Polar Urals. It was established that according to the mineral and chemical compositions the rocks of the plutons studied correspond to island-arc granitoids of I-type. Zircons from granitoids of the Rechnoy and Yalya-Pe paleovolcanoes and the Nganotsky-1 pluton yielded concordant U–Pb (SIMS) isotope ages of 456 ± 6, 454 ± 4, and 463 ± 3 Ma, respectively, which indicates the existence of an island arc within the Shchuchinskaya zone starting from the Middle–Late Ordovician. Based on the obtained zircon ages of granitoids, the country volcanics were ascribed to the Syaday Formation; the upper stratigraphic boundary of their formation was specified as the Middle–Upper Ordovician. 相似文献
2.
V. L. Andreichev A. A. Soboleva E. G. Dovzhikova E. L. Miller M. A. Coble A. N. Larionov O. V. Vakulenko S. A. Sergeev 《Doklady Earth Sciences》2017,474(1):498-502
Upper Precambrian basement of the Pechora Basin that is located between the Urals and Timan and is a part of the Pechora plate lies beneath 1–7 km of Ordovician-Cenozoic sediment cover. On the base of geophysical data and drilling the basement of the Pechora plate is subdivided into the Timan crustal block and the Bolshezemel crustal block which differ by composition and the character of magmatism. The boundary between the crustal blocks is a system of deep faults called the Pripechora and Ilych-Chikshino faults that strike in a northwestern direction, extending from the Urals to the Pechora Sea. Granitoids of Charkayu complex which were penetrated by several deep boreholes in Pripechora fault zone are interpreted as suprasubduction (island arc and collision) magmas associated with the Timan orogeny. First U–Pb dating (SIMS, using SHRIMP-II and SHRIMP-RG) of zircons from granitoids indicate that granitoid magmatism which accompanied the final stages of the Timanide orogeny occurred in the Late Vendian about 555–544 Ma. The age of zircons from granites of the 1-Charkayu borehole is 544 ± 6 Ma, from granites of 1-East Charkayu borehole is 545 ± 5 Ma, and from granodiorites of 1-South Charkayu borehole is 555 ± 2 Ma. 相似文献
3.
Doklady Earth Sciences - For timing of endogenous events in the Kharbei metamorphic complex (Polar Urals), U–Pb isotopic dating of zircons from garnet–clinozoisite–twomica... 相似文献
4.
N. B. Kuznetsov E. A. Belousova K. E. Degtyarev E. S. Pyzhova A. V. Maslov V. M. Gorozhanin E. N. Gorozhanina T. V. Romanyuk 《Doklady Earth Sciences》2016,467(2):325-330
The first results of U–Pb dating of detrital zircons from Upper Ordovician sandstones of the Bashkir uplift in the Southern Urals and U–Pb isotopic ages available for detrital zircons from six stratigraphic levels of the Riphean–Paleozoic section of this region are discussed. It is established that the long (approximately 1.5 Ga) depositional history of sedimentary sequences of the Bashkir uplift includes a peculiar period lasting from the Late Vendian to the Emsian Age of the Early Devonian (0.55–0.41 Ga). This period is characterized by the following features: (1) prevalence of material from eroded Mesoproterozoic and Early Neoproterozoic crystalline complexes among clastics with ages atypical of the Volga–Urals segment of the East European Platform basement; (2) similarity of age spectra obtained for detrital zircons from different rocks of the period: Upper Vendian–Lower Cambrian lithic sandstones and Middle Ordovician substantially quartzose sandstones. 相似文献
5.
Ryazantsev A. V. Skoblenko A. V. Golionko B. G. Artyomova O. A. 《Doklady Earth Sciences》2021,501(2):1009-1014
Doklady Earth Sciences - Metagabbroid garnet amphibolite formed after high-pressure granulite with an estimated P–T peak of 12–16 kbar at 700–790°C occurs at the sole of the... 相似文献
6.
The data on the geochemistry and geochronology of zircons from wehrlites and clinopyroxenites of the dunite–wehrlite–clinopyroxenite banded complex that lies at the base of the crustal section of the ophiolite complex of the Nurali massif are presented. The obtained U–Pb age of the banded complex of 450 ± 4 Ma differs markedly from the previous age data. According to REE distribution patterns zircons from ultramafic rocks are attributed to the magmatic type and they indicate the age and supposed genetic similarity of the above rocks with lherzolites and dunites from the mantle section of the Nurali massif. 相似文献
7.
Lobach-Zhuchenko S. B. Kaulina T. V. Marin Yu. B. Yurchenko A. V. Skublov S. G. Egorova Yu. S. Galankina O. L. Sergeev S. A. 《Doklady Earth Sciences》2019,484(1):101-104
Doklady Earth Sciences - Data on the U–Pb (SIMS SHRIMP-II) age (3628 ± 38 and 2845 ± 65 Ma) of zircon from the inclusion of mafic granulite in gneiss–enderbites of the Bug... 相似文献
8.
A. A. Krasnobaev V. N. Puchkov N. D. Sergeeva S. V. Busharina 《Geochemistry International》2017,55(6):521-534
The paper reports the results of mineralogical, geochemical, and geochronological (TIMS and SHRIMP) study of heterogeneous zircons from granites of the Mazara Massif, South Urals. Obtained data revealed the Mesoproterozoic age (1550–1390 Ma) of a granite protolith and the Neoproterozoic age of their formation (745–710 Ma). In the La–Sm/La diagram, the zircons of the massif occupy an intermediate position between the fields of magmatic and metasomatic (hydrothermal) zircons. This “intermediate” field is proposed to ascribe to the late magmatic zircons, which provides more reliable characterization of zircon formation throughout the entire crystallization history of a granite melt, up to the appearance of genetically metamict metasomatic hydrozircons. 相似文献
9.
Doklady Earth Sciences - The Early Paleozoic age of the protolith for gneisses in the East Uralian megazone (South Urals) is proved by zircon dating. Two metamorphic complexes have been identified... 相似文献
10.
Razumovskiy A. A. Novikov I. A. Ryazantsev A. V. Rud’ko S. V. Kuznetsov N. B. Yashunskiy Yu. V. 《Doklady Earth Sciences》2020,495(2):867-871
Doklady Earth Sciences - U–Th–Pb (SHRIMP II) isotopic dating of accessory zircons from Vendian (Ediacaran) ash tuffs of the Basa formation section (Asha Group, Southern Ural) was... 相似文献
11.
Tretyakov A. A. Degtyarev K. E. Kanygina N. A. Danukalov N. K. 《Doklady Earth Sciences》2020,494(1):670-674
Doklady Earth Sciences - The metamorphosed differentiated volcanogenic strata of the Aralbai Group have been studied in the eastern part of the Precambrian Ulutau massif of Central Kazakhstan. The... 相似文献
12.
Golionko B. G. Ryazantsev A. V. Degtyarev K. E. Kanygina N. A. Kuznetsov N. B. Sheshukov V. S. Dubensky A. S. Gareev B. I. 《Doklady Earth Sciences》2020,493(2):578-583
Doklady Earth Sciences - The first U–Pb (LA–ICP–MS) isotope dating of detrital zircons from quartzites of two strata of the Maksyutov metamorphic complex (Southern Urals) was... 相似文献
13.
Krasnobaev A. A. Puchkov V. N. Sergeeva N. D. Busharina S. V. 《Doklady Earth Sciences》2019,486(2):687-691
Doklady Earth Sciences - The lack of reliable geochronological data for the Vendian deposits of the Urals and other regions is one reason why there is still uncertainty in the age estimates of the... 相似文献
14.
Yu. L. Ronkin M. E. Pritchin E. I. Soroka A. Gerdes V. N. Puchkov S. V. Busharina 《Doklady Earth Sciences》2016,469(1):665-669
New results of U–Pb LA ICP–MS dating of zircon from andesite samples cropping out on the western wall of the Saf’yanovka quarry (57°22′58.88″ N, 61°31′50.85″ E) in the synonymous Cu–Zn-bearing massive sulfide deposit of the Urals type are considered. The position of data points of the U–Pb systematics in the 207Pb/235U–206Pb/238U plot determines a cluster practically corresponding to the concordant U–Pb age: 422.8 ± 2.0 Ma. This date indicates for the first time the presence of Pridolian volcanogenic rocks in the East Urals megazone of the Middle Urals. 相似文献
15.
U–Pb Age and Hf–Nd–Sr Isotopic Systematics of Vein Rocks of the Volkovsky Massif,Middle Urals,Russia
E. V. Anikina K. N. Malitch E. A. Belousova I. Yu. Badanina N. G. Soloshenko I. A. Rusin A. V. Alekseev 《Geochemistry International》2018,56(3):199-210
This paper reports chemical, geochronological, and Hf–Nd–Sr isotopic-geochemical data on granite, leucogabbro, and microgabbro porphyrite vein bodies in the gabbro of the Volkovsky massif. It was proved that the vein granite and leucogabbro are genetically related to the leucogabbro–anorthosite–plagiogranite (anorthosite–granite) series of the Urals Platinum Belt. The granite was dated by U-Pb laser ablation inductively coupled plasma mass spectrometric method at 409.0 ± 2.3 Ma. The rock has 87Sr/86Sr(409 Ма) = 0.70358, high εNd(409 Ма) = 6.4–6.5, and εHf(409 Ма) ≥ 10.8. Similar values of 87Sr/86Sr(409 Ма) = 0.70370 and εNd(409 Ма) = 5.9 were obtained for the vein leucogabbro. The isotopic-geochemical data are consistent with existing concept of the formation of the leucogabbro–anorthosite–plagiogranite (anorthosite–granite) series through partial melting of the olivine gabbro. The measured 143Nd/144Nd = 0.512939 value obtained for the microgabbro porphyrite reflects their more radiogenic composition and likely a mantle source. The granite, associated leucogabbro, and microgabbro porphyrite were emplaced at the final magmatic stage in the massif evolution. This event marks the upper age boundary of the Au–Pd mineralization related to the gabbroic rocks. The vein rocks lack any signs of the mineralization. However, it is highly probable that they were sources of energy and fluid for reworking of the earlier olivine gabbro and redeposition of ore components in this rock. 相似文献
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17.
Doklady Earth Sciences - Based on the first results of massive U–Pb dating of detrital zircons from the basal deposits of the Upper Precambrian section in the Subpolar Urals, their age is... 相似文献
18.
V. K. Kuzmin V. A. Glebovitsky V. F. Proskurnin E. S. Bogomolov V. N. Zelepugin N. V. Rodionov Yu. Yu. Yurchenko 《Doklady Earth Sciences》2018,478(1):31-35
The first results of U–Pb SIMS geochronological and Nd–Sr isotope–geochemical studies of the Yurovka Complex metavolcanics and granitoids of the Luktur Complex belonging to the Yurovka Swell yielded a Paleoproterozoic age of their formation pointing to a considerable Paleoproterozoic continental crust formation event. These data allow us to reconsider existing ideas about the similarity of the composition and age of the basement of the Yurovka Swell and that of the Paleoarchaean Kukhtui Swell of the Okhotsk Massif. 相似文献
19.
Krasotkina A. O. Skublov S. G. Kuznetsov A. B. Makeyev A. B. Astafjev B. Yu. Voinova O. A. 《Doklady Earth Sciences》2020,495(2):872-879
Doklady Earth Sciences - Isotope–geochemical study of zircon from leucoxene–quartz sandstone of the Yarega deposit in South Timan was conducted for the first time using the Sensitive... 相似文献
20.
Antonyuk R. M. Stepanets V. G. Degtyarev K. E. Tretyakov A. A. Bekenova B. K. Levin V. L. Li E. S. 《Doklady Earth Sciences》2021,500(2):826-832
Doklady Earth Sciences - Accessory zircon extracted from serpentinized dunite and harzburgite of the Tekturmas Zone of Central Kazakhstan, which is one of the largest ophiolite zones in the western... 相似文献