Zircons from Collisional Granites, Garhwal Himalaya, NW India: U–TH–Pb Age, Geochemistry and Protolith Constraints

: In the present work, we studied zircons from the less foliated granites of the Chail Group, which form a thrust sheet of the Lesser Himalayan Sequences, Garhwal region. Compositionally, these granites are S–type, formed in a collisional tectonic setting. Zircons possess an internal structure, mineral inclusions, and geochemical characteristics typical of magmatic origin. The U–Th–Pb geochronology and geochemistry were assessed using the laser ablation multi–collector inductively coupled plasma spectrometry (LA–ICP–MS) technique. U–Th–Pb isotope dating of zircons from two different samples revealed their age, estimated from the upper intersection of the discordia, to be 1845 ± 19 Ma. Zircons from one sample contained inherited cores belonging to three age groups: Paleoarchean (3.52 Ga), Neoarchean (2.78 Ga and 2.62 Ga), and Paleoproterozoic (2.1 Ga). Zircons with ages of 3.52, 2.62, and 2.1 Ga were interpreted as magmatic based on their geochemical characteristics. The 2.78 Ga core was interpreted as metamorphic. The observed inheritance is consistent with the melting of sedimentary rocks. The inherited zircons could have originated from Aravalli and Bundelkhand Craton and Paleoproterozoic Aravalli Fold Belt rocks. This confirms that the studied granites are S–type and could have been formed in a collisional environment at 1.85 Ga on the western flank of the Columbia Supercontinent.


Introduction
Zircon (ZrSiO4) is an accessory mineral constituent of the majority of igneous and metamorphic rocks, with the zirconium element (Zr) serving as a structural constituent [1]. Trace elements (e.g., U, Th, Hf, Y and Lanthanide-rare earth elements (REEs)) are present in zircons in significant amounts [2][3][4]. Zircon resists alteration in a wide variety of geological settings. The isotopic ratios of the elements within the zircons provide ages and parent magma constraints because of their early formation and refractory nature during subsequent events [1,[5][6][7]. The U-Pb ages determined from zircons have traditionally been considered the most accurate method for determining the meaningful crystallization age of granitoids. Additionally, zircon geochemistry can provide valuable information to establish the conditions of the environment under which the granitoids were emplaced.
The use of zircons as geochronometers is significant when geological criteria for rock dating are hard to determine due to the architectural characteristics of the study area. For example, Himalayan and other collisional orogens are collages of thrust sheets (Figure 1), where most contacts are tectonic and create difficulties in estimating the relative ages of geological bodies. In Lesser Himalayan Sequences (LHS), the thrust sheets comprising variably deformed and low-to-medium-grade metamorphosed igneous and sedimentary rocks lack distinctive field characteristics. Dating of the rocks within the thrust sheets and the correlation of ages and inherited age patterns to other tectonic units may help to characterize these sheets.
Geochronological data derived from Himalayan granitoids reveal their emplacement, cooling, and exhumation history [8]. These data show distinct periods of magmatic activity around 2100-1800, 1200-1000, 600-400, 100-50, and  Ma in the region [9]. Various geochemical, geochronological, and isotopic data have been used extensively in previous research on the Himalayas, indicating that granitic magmas formed during rifting, subduction, or accretion events [10][11][12][13]. The zircon U-Th-Pb ages of Lesser Himalayan granites range from around 2200 to 1750 Ma, and their age pattern resembles the ages obtained from the Columbia Supercontinent in the Paleoproterozoic time [14].
This paper analyzes the morphological and geochemical characteristics and isotopic ages of zircons from Precambrian Lesser Himalayan granites. It determines their possible protolith based on analytical results. To date, no U-Th-Pb ages of zircons or their geochemistry have been determined for the study area.

Geological Background
Four major tectonic zones are identified laterally from south to north in the Himalayan belt, with a length of more than 2400 km: (1) Sub-Himalaya, (2) Lesser Himalayan Sequences, (3) Higher Himalayan Crystalline, and (4) Tethyan Himalaya (Figure 1, [15]) [16,17]. The Sub-Himalaya thrusts over the Indo-Gangetic plane along the Main Frontal Thrust (MFT), comprising Miocene to Pleistocene molasses and sediments derived from Himalaya [18]. The Lesser Himalayan Sequences consist of Paleoproterozoic to Early Mesoproterozoic rocks unconformably overlain by Early Cambrian, Upper Paleozoic to Cenozoic rocks and thrust over the Sub-Himalaya along the Main Boundary Thrust (MBT) [19]. The north-dipping Main Central Thrust (MCT) is one of the essential tectonic structures in the Himalayas. It is recognized as an intra-continental shear zone associated with isograde inverted metamorphism [20]. MCT separates Lesser Himalayan Sequences from Higher Himalayan Crystallines. Higher Himalayan Crystallines comprise medium-to high-grade metamorphic sequences ranging from greenschist to upper amphibolite facies [21] and are intruded by granites of Ordovician (c. 485-440 Ma) and early Miocene (c. 22 Ma) age.
The study area comprises the Chail/Ramgarh thrust sheets of Lesser Himalayan Sequences (LHS) in the Garhwal region [22], considered an eastward extension of the Ramgarh Group [23,24]. The Chail Group is a nappe overlaying the poorly metamorphosed LHS, constrained by the Jutogh and Chail Thrusts [21]. Jutogh-Almora and Chail/Ramgarh have been identified as low-to-medium-grade metasedimentary thrust sheets in LHS [18] (Figure 2). Paleoproterozoic granite gneiss and granite augen gneiss are an integral component of LHS. These Paleoproterozoic rocks in the Chail/Ramgarh Group occur as less foliated granites and gneisses with augen gneisses [24,25]. The Chail/Ramgarh Group comprises a package of low-grade metamorphic rocks, including phyllites, phyllitic quartzite, psammitic schists, orthoquartzites, chlorite schist limestones, and meta-basics [26]. Rb-Sr isochron ages for granite bodies adjacent to the study area (Chirbatiya Khal granites) are dated 1768 ± 131 Ma (4 points) with an initial 86 Sr/ 87 Sr ratio of 0.732 ± 0.147 [27]. Rb-Sr dating for granites exposed in the Ghuttu area (Chailli granites) gave an isochron age of 2120 ± 60 Ma, with an initial ratio of 0.710 ± 0.020 interpreted as the age of emplacement for these granites [28]. These ages are potentially imprecise using only the Rb-Sr isochron technique, which can give misleading ages due to the complications of recrystallization in old and deformed rocks; however, the initial ratios are likely relatively accurate. They suggest a source of old and/or radiogenic material.
The granites are well-exposed around Toneta village, situated on the Tilwara-Mayali State Highway (Figure 3). At some places in the Toneta village area, the granites are foliated and show gneissose structures. Both samples, TG17-01 (Figure 4a,b) and TG17-04 ( Figure 4c,d), are coarse-grained and less foliated, containing quartz and feldspar megacrysts with biotite and muscovite minerals. In relatively undeformed granite, where a porphyritic texture is clear, muscovite is apparently primary, making it likely that the protolith is peraluminous (contains muscovite ± biotite and no primary amphibole). These two mica granites have an accessory phase assemblage of zircon, apatite, minor tourmaline, and minor garnet in our two samples. The garnet is strongly associated with muscovite in foliated planes. Most of the minerals observed under the microscope are subhedral, although euhedral mineral grains are also present in the rocks (Figure 5a). Mica minerals follow the foliation direction. Muscovite has a parallel extension and second-order color under cross-polarized light (Figure 5b). Millimeter subhedral garnet grains have also been observed in some thin sections.   (Mineral symbols taken from [29]).

S-Type Characteristics of Granites
The studied granite, TG17-01 and TG17-04 (Table S1), in whole-rock geochemical analysis (detailed methodology described in Appendix A), has SiO2, 73 [30] and the K2O versus Na2O diagram [31], samples are falls in an S-type granite field ( Figure S1a,b). The low P2O5 content and its negative correlation with SiO2 suggest that the granites have S-type affinity ( Figure S1c). Moreover, in SiO2 versus K2O + Na2O-CaO diagrams [32], both samples are plotted in an S-type granite field ( Figure S1d). In a source discrimination diagram [33], the sample plot in the meta-sediments field indicates that the granitic magma is the product of the partial melting of metasedimentary rocks ( Figure S2). The trace elements Ba, Sr, Nb, and Ti, are low, and Rb, Th, U, and Pb are high in the samples [34] (Figure S3), typical for S-type granites and interpreted as syn-collision on the discrimination diagram after [35] ( Figure S4).

Zircon U-Th-Pb Geochronology
Zircon separation was performed at the Wadia Institute of Himalayan Geology (WIHG), Dehradun, India, with the procedure outlined in the following [36,37]. A quantity of 4-5 kg of granite from each sample was crushed using a jaw crusher and a disk mill. To concentrate heavy minerals in the samples, magnetic, gravitational, and electrical methods were used. Heavy liquid (bromoform) was used to separate zircons and other heavy minerals. The zircons were hand-picked under a binocular microscope. Epoxy resin was used to mount the zircons. We polished the zircons in order to expose their surfaces. To investigate their internal structure, they were then examined under optical, back-scatter electron (BSE), and cathodoluminescence (CL) microscopes. The mineral structure and inclusion chemistry of the zircon and BSE images were obtained with an acceleration voltage of 15 kV, a beam current of 15 ± 0.05 nA, and a counting time of 10-15 s using a Vega II LSH (TESCAN, Brno, Czech Republic) scanning electron microscope (SEM) equipped with an energy-dispersive microanalyzer (INCA Energy 350 from the Institute of Geology of the Karelian Research Center, RAS, Petrozavodsk, Russia).
In situ analyses of U-Th-Pb isotopes and trace elements of zircons were performed using ICP-MS Agilent 7500 Ce with a Complex Pro102 (LA-ICP-MS) laser ablation system with a ~30 μm spot diameter at Peking University, China. Helium was used to enhance the transport efficiency, and nitrogen was added to the argon plasma to lower the detection limit and improve analytical precision. Each spot incorporated a background acquisition of approximately 15 s (gas blank), followed by 30 s of sample data acquisition. The laser output fluence was constant and set to 6.0 J/cm 2 . The offline selection and integration of analytical and background signals, correction for time drift, and quantitative calibration for trace element analysis and U-Pb dating were performed with ICPMSData-Cal and Glitter 4.0 software (CSIRO). Its algorithm is based on the creation of a threedimensional diagram in coordinates 206 Pb/ 238 U, 207 Pb/ 235 U, and 208 Pb/ 232 Th; it includes the solution of a system of the equations connecting the maintenance of radiogenic and general Pb, the maintenance of modern non-radiogenic Pb, and the age and quantity of the lost Pb [38]. The zircon 91500 [39] was used as the primary reference material and Plesovice [40] as the secondary. The average value of age during the analytical session for the Plesovice (the accepted age-337.13 ± 0.37 Ma [40]) was 347 ± 15 Ma, and for 91500 (the accepted age-1062.4 ± 0.4 Ma [39]), it was 1071 ± 35 Ma. Common Pb correction was performed using the LAM-ICPMS Common Lead Correction calibration algorithm [41]. Data processing was carried out using the SQUID and Isoplot 4 programs [42]. Analytical errors for individual analyses are given with one-sigma uncertainty. In contrast, the mean ages for the pooled analyses are quoted with two-sigma uncertainty. The reference materials used in the analysis for trace elements were NIST SRM 610, 612, 614 (Standard Reference Material of the National Institute of Standards and Technology, USA) [43]. They were used as samples for calibration, quality control (Table S2), and inter-laboratory comparisons of concentration trace elements.

Zircon Morphology
The zircon crystals in Sample TG17-01 are transparent, pale yellowish-brownish, or colorless (clear) (uncommon). The degree of fracturing varies from almost going unnoticed at the grain margins to becoming highly longitudinal-transverse over the entire grain surface. Larger fractures are often filled with quartz. The crystals fall into two morphological types: sub-idiomorphic prismatic crystals with an elongation coefficient of 1.5-2.5 (approximately 90% of the samples) predominate; isometric grains, typically with many small, irregular facets, are less common. The prismatic crystals display sharp and obtuse dipyramids, whereas, in more elongated crystals, sharp dipyramids are not wellshaped. The common occurrence of asymmetrical crystals indicates zircon crystallization in the presence of the closely spaced grains of other minerals. Crystals with a prismatic habit typically exhibit slightly rounded facets. Their grains are 100-210 μm in size. Their internal structure in CL and BSE images is homogeneous for most zircons (no inclusions), except for one grain. The grain with spot T01-9 (Table 1) is dark in CL, with many microveins. It is only one of the examples of a metamictic zircon. Some of the grains show slight zoning near their tips ( Figure 6a). There is a variety of included mineral phases. They are micron-sized (10-20 μm) quartz, apatite, thorite, biotite, and allanite inclusions that occur in the central portions of zircon grains. In contrast, intergrowths with monazite, up to 30 μm in size, are encountered at the margins.
Sample TG17-04 contains two morphological types of zircon grains: (1) sub-idiomorphic grains are present, and idiomorphic prismatic crystals of zircon type or their parts, often with oscillation zoning, retaining or partially retaining dipyramid facets, are less common; (2) ellipsoidal grains with rounded facets. Morphological (zircon) type 1 occurs as transparent to semi-transparent light-colored crystals with a short prismatic habit. Zircons of this type make up approximately 80-90% of the total volume of this mineral in the rock. The grains vary from 60 to 200 μm, and their elongation coefficient is 1-2. The crystal form is due to the development of prisms and dipyramids. A microprobe study of zircons in BSE and CL shows that grains are relatively well-preserved. The surface of the zircon grains displays various degrees of longitudinal-transverse fracturing; grains with a smooth surface and with no fractures are less common. The internal structure of some of the grains is multizonal; the zones are distributed symmetrically (Figure 7a). There are three metamictic grains with dark CL or with dark micro-veins only.
A second morphological type of zircon occurs as ellipsoidal grains with subdued outlines, with no dipyramid facets characteristic of type 1. Such grains are less common, amounting to 10-20% in the rock and forming light-yellow semi-transparent crystals, no more than 80 μm in size. The grain surface is dull, rough, and displays minor transverse fracturing. The internal structure in BSE is homogeneous.
The internal structure of these two morphotypes displays the presence (in some cases) of complex crystals with homogeneous internal cores that are well-defined in CL images ( Figure 7a). In zircons of type 2, cores occupy two thirds of the entire grain volume, and their shape is markedly different from the external rim. This is also indicated by the higher idiomorphism and the presence of clearly traceable prismatic facets. There are mineral inclusions in the internal zone (core). However, these are too small (less than 3 μm) to be reliably identified. The cores of zircons of morphotype 1 are less conspicuous, and their shape is consistent with the external rim; the core structure in a CL image is more homogeneous. The zircons of both morphological types typically display solid-phase biotite, thorite, monazite, and apatite inclusions in both the central and marginal portions of grains. In addition, zircon-quartz intergrowths are encountered.

U-Th-Pb Isotope Data from Zircons
U-Th-Pb age isotope LA-ICP-MS analysis was performed on 29 points from 17 grains in Sample TG17-01 and 43 points from 37 zircon grains in Sample TG17-04 (Table  1). The 207 Pb/ 206 Pb age of most TG17-01 zircons is 2.0-1.6 Ga, with a maximum of approximately 1.8 Ga (Figure 6b; Table 1). All analytical points are formed on the U-Pb diagram with a concordia single isochron line-discordia ( Figure 6c)-as is common for discordant U-Pb age data [38]. The line plotted using all analytical points (n = 29) has an upper intersection with concordia at 1846 ± 26 Ma and a lower intersection at 108 ± 40 Ma (Figure 6c). If only analytical points with a discordance (D, Table 1) of less than 100% (D < 100%) are used to estimate U-Pb age by the upper intersection at 1851 ± 36 Ma, the lower value at 131 ± 120 Ma (MSWD = 2.0, n = 15) ( Figure 6c) is obtained. This 1851 ± 36 Ma age can be regarded as the most precise crystallization age of zircons in TG17-01 granite, and 108 ± 40 Ma is the age of Pb lost during tectonic events.
The 207 Pb/ 206 Pb age of most TG17-04 zircons is 2.0-1.6 Ga, with a maximum of approximately 1.8 Ga (Figure 7b; Table 1). However, there are three peaks with ages of (1) 3.5 Ga, (2) 2.62 and 2.78 Ga, and (3) ca. 2.1 Ga (Figure 7c; Table 1). All analytical points (excluding those older than 1.95 Ga) are formed on the U-Pb diagram with a concordia single isochron line (Figure 7c), as is common for discordant U-Pb age data [44]. The U-Pb age of the most common group of zircons (Figure 7c), estimated from the upper intersection with discordia using all analytical points, is 1845 ± 28 Ma, and the lower intersection of 124 ± 54 Ma. This first age is consistent with the magmatic stage of granite formation and the second with an age of terminal tectonic events. Using the most concordant values (D < 30%), the upper intersection of discordia is estimated as 1839 ± 38 Ma (Figure 7c). There is also the existence of analytical points of the core with older ages: the Paleoproterozoic (2.1 Ga), Neoarchean (2.62 Ga and 2.78 Ga), and Paleoarchean (3.52 Ga). These data indicate that the protolith of these granites contained detrital zircons of different ages, possibly as redeposited clasts.   , Paleoproterozoic core (red), and Paleoproterozoic magmatic (green) zircons from the granite (Sample TG17-04); t1-the upper intersection of discordia age; t2-the lower intersection of discordia age; t1-1839 ± 38 Ma is the age for magmatic zircon with D < 30%, t1*-1845 ± 28 Ma is age all analytical points of magmatic zircons, t1**-2117 ± 47 Ma is the age of Paleoproterozoic core; with D < 30% (red color) is 1839 ± 38 Ma (t1), and for all (pink are zircon with D > 30%) analytical points are 1845 ± 28 Ma (t1*). (t1-the upper intersection of discordia age; t2-the lower intersection of discordia age); (d) Weighted average 207 Pb/ 206 Pb age of zircons with age older 1.95 Ga (color are same as in 7c)

Zircon Geochemistry
The geochemical characteristics of the zircons discussed are also consistent with their magmatic genesis. The analytical points of zircon composition on the discrimination diagrams Y-U, Ce/Ce*, and Eu/Eu* [5] are in the granite (leucogranite) fields ( Figure 8). This means that the composition of zircons did not change significantly, despite the loss of Pb.
The average ΣLa-Lu and Y concentrations in zircons from both granite samples analyzed (3200 and 5500 ppm, respectively) are slightly higher than those in zircons from granites [1]. However, there is a significant difference in the composition of zircons with different degrees of discordance (D): zircons with D > 100 are enriched with REE and Y. Some differences in the composition of zircons from the two samples discussed are also noteworthy.
The REE concentrations are typically igneous zircon with Lu concentrations 100 s of times greater than La, and all have a positive Ce anomaly and a negative Eu anomaly. Using D as a demarcation, the more discordant and TE-rich zircons have greater REE concentrations. For TG17-01, the high D zircons include the greatest Eu anomalies, suggesting that the zircons grew from a fractionating magma and that plagioclase was a significant fractionating phase. TG17-04 shows somewhat different behavior. In this sample, the most discordant have similar Eu anomalies.
Most of the zircon cores are plotted in the field of typical granitic magmas, and only the core with 2.78 Ga age shows a significant difference (spot TG04-6, Table 1), plotting in fields typical for carbonatites or mafic rocks ( Figure 8). This core is notably depleted in HREE ((Yb/Sm)N-0.66), which likely indicates growth in the presence of garnet and possibly a metamorphic origin. Its crystallization temperature, determined using a Ti thermometer [46], is higher (926 °C) than that of the most common grains, which could be indirectly regarded as evidence of its metamorphic genesis. Thus, zircon cores from this sample are of both magmatic and metamorphic origin.

Discussion
The geochemical analysis of zircons from the studied granites has reliably identified them as magmatic. Most of the zircons have more than a 100% degree of discordance, which correlates with the enrichment of REE, U, and Th. However, in any case, all these zircons are discriminated as magmatic (Figure 8). The study of magmatic zircons from this granite can be used to precisely estimate the U-Pb age of the magmatic stage of granites formed: 1839 ± 38 and 1851 ± 36 Ma, respectively, for each of these samples. These values are identical within the constraints of the measurement accuracy. On the diagram with a concordia, all of the least discordant analytical points from both samples form a common isochron with an upper intersection of 1845 ± 19 Ma ( Figure 10). This age can be regarded as the most valid age for the magmatic stage formation of granites. The lower intersection at 112 ± 62 Ma could be interpreted as the age of a thermal event during Indian plate subduction at ca. 80-60 Ma ago [9]. In the Paleoproterozoic era, many granites formed in the Himalayas from 1980 to 1750 Ma [12,[47][48][49] (Figure 11), and the 1.85 Ga Chail Group granites in the Garhwal Lesser Himalaya continue to be essential for any geological reconstructions. Figure 10. Diagram with a concordia for zircons from granite (Sample TG17-01-red and TG17-04-black). U-Pb age magmatic zircons are 1845 ± 19 Ma. t1-the upper intersection of discordia age; t2-the lower intersection of discordia age.
Evidence of old cores in zircons from granites varying in age from 3.5 to 2.1 Ga is analyzed to understand the genesis of the protolith. The scarce old cores of zircons can be divided into three age groups: Paleoarchean (3.52 Ga), Neoarchean (2.78 Ga and 2.62 Ga), and Paleoproterozoic (2.1 Ga). This diversity suggests that granites originated from sediments formed by the destruction of rocks varying in age from Paleoarchean to Paleoproterozoic and supports the notion that these granites are S-type granites [50].
Moreover, Neoarchean (2.58-2.5 Ga) granites are widespread in the Bundelkhand and Aravalli Cratons. The Aravalli Craton is known to contain 2.62 Ga Gingla Granite [60,61], which could have been the source of the 2.62 ± 0.05 Ga magmatic zircons in the Himalayan granitoids discussed. The Paleoproterozoic (ca 2.1 Ga) magmatic zircons in these rocks were most probably derived from the 1.90 ± 0.08 Ga Darwal Granite, formed during the Aravalli orogeny [61]. Thus, the 3.5-2.1 Ga cores of zircons from Paleoproterozoic Chail Group granites (Garhwal Lesser Himalayan) could have originated from the Aravalli and Bundelkhand Cratons and the Paleoproterozoic Aravalli Fold Belt. The old block of Indian shield crust comprised the entire western flank of the Columbia Supercontinent in the Paleoproterozoic time (ca. 1.85 Ga) [62]. Here, 1.85 Ga Chail Group granites could have been formed during accretion-collision events.
Collisional granites in orogenic belts are significant because their age can be used to estimate the minimum duration of an orogeny [63][64][65]. Most Paleoproterozoic granites in LHS (Table 3) [71,73], which are equivalent to the northwest Himachal Himalaya, Garhwal-Kumaun Lesser Himalaya, and Nepal Lesser Himalaya crystalline thrust sheets, which are derived from juvenile and crustal sources in arc-related tectonic settings (Table 3). Any part of Paleoproterozoic granite (for example, Larji-Kullu-Rampur window, NW Himalaya) could be developed in syn-to post-collision environments, as with the studied granites. Leucogranite-pegmatites from the Rangit window, Wangtu (MCT zone, Sutlej valley), Bandal (MCT zone Himachal Himalaya), and Bomdila (Arunachal Lesser Himalaya) are also developed in syn-to postcollision environments (Table 3), as evidenced by three-stage zircon Hf-model ages (2818, 2586-2424, 2393-2250 Ma) [66]. Figure 11. Histogram of the published geochronological data set on Paleoproterozoic granites of Lesser Himalayan ( Table  3) and age of studied Chail Group granites. (Star: discordant analytical points from both samples form a common isochron with an upper intersection of 1845 ± 19 Ma, Figure 10).

Conclusions
Zircons from Chail Group granites (Garhwal Lesser Himalayan) display an internal structure typical of magmatic varieties (oscillatory zoning); mineral quartz, apatite, thorite, biotite, allanite, and monazite inclusions; and geochemical characteristics (enrichment in HREE, Th/U > 0.1, and positive Ce/Ce* and negative Eu/Eu* anomalies). Hence, these zircons can be regarded as minerals formed at a magmatic stage in the evolution of granites. U-Th-Pb isotope dating of magmatic zircons from two different samples was performed to estimate their age from the upper intersection of the discordia at 1851 ± 36 (MSWD = 2.0, n = 15) and 1839 ± 38 (MSWD = 0.94, n = 13) Ma, respectively. Combining all of the least discordant analytical points from two samples to form a single isochron line on the U-Pb diagram and age 1845 ± 19 Ma (MSWD = 1.19, n = 28) estimate can be regarded as the most adequate.
The cores of three age groups-Paleoarchean (3.52 Ga), Neoarchean (2.78 Ga and 2.62 Ga), and Paleoproterozoic (2.1 Ga)-were revealed in zircons from one sample. Zircons aged 3.52, 2.62, and 2.1 Ga are regarded as magmatic based on their geochemical characteristics, and the 2.78 Ga core is metamorphic. Therefore, it can be concluded that these zircons have been derived from Aravalli and Bundelkhand Craton and Paleoproterozoic Aravalli Fold Belt rocks. Studied granites of the Chail Group were formed at 1845 Ma by melting a substrate consisting of rocks varying in age and genesis, which is characteristic of sediments. The discussed Paleoproterozoic granites were formed on the western flank of the Columbia Supercontinent during accretion-collision events.