Petrogenesis and tectonic setting of a granitic pluton in the 1 northern YaGan fault zone , North Alxa , China : Constraints 2 from whole-rock geochemistry , zircon U – Pb ages , and 3 Sr – Nd – Hf isotope compositions

A series of precise data consisting of zircon U–Pb ages, whole-rock 19 geochemistry and Sr–Nd–Hf isotope compositions from the Huhetaoergai granitic 20 pluton was collected in this study and combined with data from the western 21 Huhetaoergai, Zhuxiaogubuhe and Yagan granitic plutons to constrain the 22 petrogenesis and tectonic setting of granitic plutons in the northern Ya-Gan fault zone, 23 North Alxa, China. The Huhetaoergai pluton is composed of hornblende diorite, 24 mediumto coarse-grained biotite adamellite and coarse-grained biotite adamellite 25 Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 22 June 2018 doi:10.20944/preprints201806.0344.v1 © 2018 by the author(s). Distributed under a Creative Commons CC BY license. with K-feldspar megacrysts. The U–Pb zircon ages of biotite adamellite are 220.5 ± 26 1.9 Ma and 226.5 ± 2.4 Ma. These granitoids are I-type granites with highly 27 radiogenic initial 87Sr/86Sr of 0.708085–0.735470, negative εNd(t) average values of 28 -2.98–3.23 and high εHf(t) of 9–11.05. These features indicate the granitoids were 29 formed from magmas generated from juvenile crust. We speculate that the granitoids 30 of the Huhetaoergai pluton were emplaced during an episode of intense intraplate 31 orogenic movement evolution in an extrusional setting after a period of extensional 32 postcollisional intraplate evolution. 33


Introduction
The Central Asia Orogenic Belt (CAOB), also called the "Central Asian mobile belt", "Central Asian Fold belt" or "Altaids", is one of the largest accretionary orogens on Earth and one of the most important areas for the growth of continental shells, situated at the suture of the European, Siberian, Tarim, and Sino-Korean cratons (Fig. 1a).The northern margin of the Alxa block is located in the middle of the southern margin of the CAOB and is in the key position connecting the structural units on both sides of the CAOB; then, it is an important area to study the final closure process of the Paleo-Asian Ocean.
Previous studies have been focused on the division of the Alxa block and the stratigraphic evolution of the Precambrian in the northern margin of the Alxa block However, few studies have been conducted in the northern region of the Alxa block and in Mongolia.
The northern margin of the Alxa block is covered by the Badain Jaran Desert, and because of the formidable natural conditions, geological research is relatively scarce.Since the 1980s, some scholars have systematically studied the Paleozoic crustal evolution in the northern margin of the Alxa block, made a preliminary division of the tectonic units in this area, and established the basic pattern of tectonic evolution, which established a good foundation for future research work.
Due to the long-term interactions between different plates, the regional geologic setting of the Alxa block is extremely complex.The Alxa block is mainly composed of ophiolitic mélanges, island arcs, oceanic basins, trenches and continental margins, and three fault zones occur in this block, which are from north to south the Ya-Gan fault, Engger Us Ophiolite Belt, and Qagan Qulu Ophiolite Belt (Fig. 1b) [3][4][5].The existing studies have researched the area north of the Engel Wusu fault zone as a whole, but there is no detailed study of the structural properties of the Ya-Gan tectonic belt, which is of great importance [3].The Ya-Gan fault zone can be connected to the Mingshui-Xiaoxingshan ophiolite zone in the west, and a former study suggested that the Mingshui-Xiaoxingshan ophiolite zone is a stitching zone between the Kazakhstan plate and the Tarim plate [6].However, there is no clear evidence about the closure time and the tectonic evolution during the Paleozoic between the Kazakhstan and the Tarim plates in the northern Alxa area because an ophiolitic mélange associated with the collision of the Tarim and Kazakhstan plates has not yet been found in the Ya-Gan fault zone.
The Huhetaoergai pluton is located on the north side of the Ya-Gan fault zone and has an area of approximately 80 km 2 , one of the plutons with widespread exposure in the northern area of Alxa.In this paper, we present new data from laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) zircon U-Pb dating and analysis of trace element contents, whole-rock geochemistry, and Sr-Nd-Hf isotopes in samples from the Huhetaoergai pluton, combined with data collected from the Zhuxiaogubuhe pluton, western Huhetaoergai pluton, and Yagan pluton, with the aims of (1) outlining the petrogenesis of the pluton; (2) constraining the source and origin of the granitic magmas; and (3) discussing the tectonic setting of the pluton.

Geological background
The Huhetaoergai pluton is located northeast of Ejinaqi, occupies an area of ~80 km 2 and consists of many intrusive rocks that are intruded into Paleozoic rocks dominated by Ordovician strata (Fig. 1c).The circular Huhetaoergai pluton has sharp contacts with the surrounding rocks at inclinations of 45°~70°.In the vicinity of the contact surface, the interpenetration of apophyses is common, and assimilation and contamination are stronger where we can see xenoliths.The thermal deterioration of the surrounding rock is strong, forming a contact metamorphic belt with a width of several hundred meters [7].
The granitoids within the Huhetaoergai pluton are typically massive, leucocratic then mounted into epoxy resin blocks and polished to obtain flat surfaces.The Zircon GJ1 was used as an external standard for U-Pb dating and was analyzed twice every 5-10 analyses.Time-dependent drifts of U-Th-Pb isotopic ratios were corrected using linear interpolation (with time) for every 5-10 analyses according to the variations in GJ1 (i.e., 2 zircon GJ1 + 5-10 samples + 2 zircon GJ1) [9].The preferred U-Th-Pb isotopic ratios used for GJ1 were from Jackson et al. (2004).The uncertainty of preferred values for the external standard GJ1 was propagated to the ultimate results for the samples.In all analyzed zircon grains, the common Pb

Whole-rock major and trace element analysis
Whole-rock major and trace element compositions were analyzed at the Analytical Laboratory of the Beijing Research Institute of Uranium Geology, China.The samples were crushed in a milling machine to pass 200 mesh before major element contents were measured using an AB-104 L and PW2404 X-ray fluorescence (XRF) instrument with an analytical accuracy of approximately 1-5%.Trace element compositions were measured using ICP-MS (an ELEMENT XR 9443 instrument) with an analytical accuracy of better than 5%.

Sr-Nd isotope composition analysis
Prior to isotope analysis, the samples were crushed in a milling machine to pass 200 mesh.Sr-Nd isotope compositions were measured using multicollector thermal ionization mass spectrometer (MC-TIMS) housed at Langfang Geoscience

Lu-Hf isotope composition analysis
Zircon Hf isotope analysis was carried out in situ using an ESI NWR193 laser ablation microprobe attached to a Neptune Plus Multicollector ICP-MS at Beijing CreaTech Testing International Co., Ltd., Beijing.Instrumental conditions and data acquisition were comprehensively described by Wu et al. (2006) [13] and Hou et al.
(2007) [14].A stationary spot was used for the present analyses, with a beam diameter of 40 μm depending on the size of ablated domains.Helium was used as the carrier gas to transport the ablated sample from the laser ablation cell to the ICP-MS torch via a mixing chamber mixed with argon.To correct the isobaric interferences of 176Lu and 176Yb on 176Hf, 176Lu/175Lu = 0.02658 and 176Yb/173Yb = 0.796218 ratios were determined [15].For instrumental mass bias correction, Yb isotope ratios were normalized to a 172Yb/173Yb ratio of 1.35274 [15] and Hf isotope ratios to a 179Hf/177Hf ratio of 0.7325 using an exponential law.The mass bias behavior of Lu was assumed to follow that of Yb, and the mass bias correction protocol details were described by Wu et al. (2006) [13] and Hou et al. (2007) [14].Zircon GJ1 was used as the reference standard during our routine analyses with a weighted mean 176Hf/177Hf ratio of 0.282007 ± 0.000007 (2σ, n = 36).This value is not distinguishable from a weighted mean 176Hf/177Hf ratio of 0.282000 ± 0.000005 (2σ) using the solution analysis method by Morel et al. (2008) [16].

Zircon U-Pb dating results
Zircons crystals from samples Ch08 and Yh22 are mainly euhedral and colorless or light yellow, and the morphologies of zircons are mainly granular and columnar; zircons have a high degree of crystallinity and exhibit the characteristics of magmatic zircons.Additionally, the samples have high Th/U ratios (between 0.41 and 1.31), which are consistent with a magmatic genesis [17][18].
Zircon crystals from sample Ch08 are typically euhedral with lengths ranging from 150 to 300 µm and length-to-width ratios ranging from 1:1 to 3:1.
The rocks have moderate alkali contents with all data plotting in the calc-alkaline field (Fig. 5c).Some rocks are fall into the pure crustal partial melts feild and some show higher Mg # = Mg/(Mg+FeT) than pure crustal partial melts (Fig. 5d).
The chondrite-normalized REE patterns and primitive mantle-normalized trace element patterns of the diorites such as samples Ch03 and Ch06 are similar to those of the granitoids.The heavy and medium REEs (HREEs and MREEs) in Ch03 and Ch06 are higher than those in the granitoids.
All the geochemical features of granitoids in the Huhetaoergai pluton are similar to those of the other three granitoids -western Huhetaoergai, Zhuxiaogubuhe and Yagan -cited from previously published data [21][22].

Sr-Nd isotopic compositions
The Rb-Sr and Sm-Nd isotopic compositions of YT-20 and YT-21 from the granites in the Huhetaoergai pluton are listed in

Is the pluton in the northern Ya-Gan fault zone composed of S-, I-, or A-type granites?
Granitic rocks can be subdivided into I-, S-, and A-types based on their geochemical characteristics, protoliths, and tectonic settings [27][28][29][30][31][32].The diagrams for Zr-SiO2 and Ce-SiO2 from the bulk rock (Fig. 7a,b) indicate that the majority of the samples in the northern Ya-Gan fault zone plot in the I-type granite area and a small number are found in the A-type region.In addition, they have low 10000Ga/Al values (2.31-2.68;mean = 2.45), which are lower than those of typical A-type granites (Whalen 1987).In the Zr-10000Ga/Al and Y-10000Ga/Al diagrams, most of the samples plot in the field of I & S granites (Fig. 7c, d).Corundum is found in the calculation of standard minerals (Table 6), which is not consistent with S-type granite.
The granitoids in the Huhetaoergai pluton have relatively low A/CNK ratios (average 0.98), and there is a negative correlation between SiO2 and P2O5, which indicates that the rocks are most likely I-type granites [33][34].Furthermore, the temperatures for these granites calculated by the model of the zircon saturation thermometer are 660°C-831°C, which are not in line with those for typical A-type granites at approximately 900°C (Fig. 8a).Consequently, these granitoids are concluded to likely be I-type granites.

Fractional crystallization of the pluton in the northern Ya-Gan fault zone
Within the granitoids of the pluton in the northern Ya-Gan fault zone, strong fractionation of plagioclase, biotite, and K-feldspar is indicated by negative correlations of SiO2 with CaO, TFe2O3, MgO, K2O, MnO, Na2O, P2O5, and Al2O3 (Fig. 4).These features suggest that fractional crystallization played a major role in the magma process.
Chondrite-normalized REE plots of all samples show right-dipping oblique trends and slightly depleted Eu, despite differences in element contents.The slope of the LREE curve is greater than that of the HREE curve, which shows that the magma has undergone differentiation and different degrees of local melting (Fig. 6a).The weak negative Eu anomalies indicate that the plagioclase in the samples has undergone dissociation and crystallization.In the partial melting process, there is residual plagioclase in the source region, or there is crystallization of plagioclase in the process of crystal differentiation (Fig. 6a).
The depletions in Ti, P, Sr, Ba, and Nb in the primitive mantle-normalized trace element patterns indicate the separation and crystallization of plagioclase, K-feldspar, apatite, ilmenite and other minerals (Fig. 6 b) The crystallization temperatures of the granites were approximately 660-830°C (Fig. 8a); the decreasing Eu/Eu* (or negative Eu anomalies) with decreasing Sr is consistent with feldspar removal, especially plagioclase, during magma evolution [35] (Fig. 8b).There are negative correlations of Rb with Ba and Sr, suggesting the fractionation of alkali feldspar and plagioclase was extensive (Fig. 8c, d).
The Mg# values for the Huhetaoergai pluton are scattered (Fig. 5d).High magnesium indicates that the mafic component is from juvenile crust or the mantle.In other words, mantle material was injected into the crust, leading the increase in Mg#.
This result shows that the source of the magma in the northern Ya-Gan fault zone was mixing of crust and mantle.
Values of εHf(t) range from 9 to 11.05, which are relatively high, indicating that the magma source was juvenile crust.The variation range for εHf(t) is so narrow that there is no mixing material between the crust and added mantle.The difference in the Hf model ages (TDM2) and (TDM) and the ages of the granitoids is relatively large, which suggests that the granites experienced secondary remelting of juvenile crust but were not directly separated from the mantle.As shown in Fig. 10, the granitoids also probably originated from juvenile crust, which is discovered for the first time in this paper through the Hf isotopic compositions.
One sample with low Nd may have resulted from crustal material being mixed during the ascending process.One other sample plots in the OIB field on Fig. 10.The juvenile crust may have been evolved from OIB-type mantle magma.For the other samples, the TDM2 model ages of Hf and Nd indicate that OIB magma entered the crust and formed juvenile crust, which corresponded to a period of crustal growth.
There are diorite inclusions in hand specimens Ch03 and Ch06 that contain quartz and amphibole.Since there is no quartz in the mantle, the source area should be the crust.The minerals in inclusion and granites are the same, and the chondrite-normalized REE patterns and primitive mantle-normalized trace element patterns of Ch03 and Ch06 are similar to those of the granitoids, which indicates that the inclusion bodies and the granites may be considered homologous.The isotopes indicate that the granite originated from juvenile crust and that the diorites such as samples Ch03 and Ch06 were also generated from juvenile crust.In addition, the inclusion injected from the mantle contains olivine, pyroxene, amphibole or garnet and does not contain quartz, so we believe that the inclusion may be the residual material in the source area after the granite melted.
The HREEs and MREEs in Ch03 and Ch06 are high, from which we can speculate that there was much amphibole and garnet left in the source area.In addition, the mineral components of diorite are consistent with the granitoids in the pluton, indicating that the residual materials such as amphibole and garnet in the source area were captured by the magma.The presence of garnets in the source area also indicates high-grade metamorphic rocks, which are deeply buried lower crustal materials.
I-type granitoids are commonly believed to form by the partial melting of preexisting meta-igneous rocks [27] and the mixing of felsic with mafic magmas [38][39][40][41][42].The Sm/Nd ratios range from 0.14~0.The low εNd(t) may indicate that the source of the magma was the mantle or the juvenile crust.As shown in Fig. 9a and b, the granitoids probably originated from the upper continental crust or the mantle.

Tectonic setting of the pluton in the northern Ya-Gan fault
In the Nb vs. Y and Yb vs. Ta discrimination diagrams for tectonic setting (Fig. 11a,     b), all of the samples fall into the VAG+syn-COLG field.In the Rb vs. Y+Nb discrimination diagram for tectonic setting (Fig. 11c), all of the samples plot in the VAG and post-COLG field, suggesting that they have a volcanic arc setting.Finally, as illustrated by the R1 vs. R2 discrimination in Fig. 11d, an evolutionary trend from pre-plate collision to syn-collision to post-orogenic and late orogenic stages is observed, which is consistent with the above tectonic discrimination.
Thus, the magmatism evolved from arc magma to collisional magma, indicating a subduction-accretion event in the northern Ya-Gan fault.However, the ocean represented by the Ya-Gan fault was closed before the Early Permian (283.2 ± 2.2 Ma) (Zheng, 2013).We speculate that the granitoids of the Huhetaoergai pluton were emplaced during an episode of intensive intraplate orogenic movement that evolved to extrusional setting after a period of extensional postcollisional intraplate evolution, and the formation mechanism of the granites was related to crustal thickening in a compressional setting.
The chondrite-normalized REE patterns and primitive mantle-normalized trace element patterns show negative anomalies for Nb, Ti and other HFSEs indicating that the granites of the pluton in the northern Ya-Gan fault zone are active continental granites with arc-related characteristics.The calcareous granodiorite magma formed by the partial melting of the overlying young crust by magma underplating.

The geodynamics of the tectono-magmatic events in the northern Ya-Gan fault zone
Recently, the formation ages of the plutons in the northern Ya-Gan fault zone have been addressed, and many stages of magma emplacement have been recorded  4).
In the northern Ya-Gan fault belt, from west to east, the Zhuxiaogubuhe, western Huhetaoergai, Huhetaoergai and Yagan plutons are located.The long axis direction of the plutons coincides with the construction line direction, and the characteristics of the granites in each pluton are shown in Table 4.
(1) Precambrian There are few Cambrian strata in the northern Ya-Gan tectonic zone.From the analysis of geochemistry and chronology, we can conclude the western Huhetaoergai pluton was located in a postcollision environment at 890 Ma, which resulted from the southward subduction of the Paleo-Asian Ocean and coincides with the time of the assembly of the Rodinia continent (Fig. 12a) [45][46][47][48].As shown in Table .3 and Table .5, the TDM2 model age of granitoids in Huhetaoergai pluton probably range from 549-678 Ma, when a portion of basic rock is separated from the depleted mantle and remained in the lower crust with the asthenosphere intrusion mixed, during which the OIB magma entered.However, the TDM2 model age of other granitoids in western Huhetaoergai, Zhuxiaogubuhe and Yagan pluton range 1040-1685 Ma, when the asthenosphere intrusion and upper crust mixed.
( granodiorite appeared at 356 Ma, which involved crystallization and differentiation of magmas from the mixing of mantle and crust. There was continuous Carboniferous deposition in the northern region, and the lithology is yellow-green and fine feldspathic hard sandstones and quartz sandstones, which represent the coast and shallow sea in a near-shore and oxygen-rich environment.Therefore, the western Huhetaoergai pluton should have been in a volcanic arc environment in the Early Carboniferous, the oceans represented by the Ya-Gan fault remained open at this time, and subduction was ongoing (Fig. 12b).
The Zhuxiaogubuhe and Yagan plutons were generated at 286 Ma and 283 Ma, respectively, in volcanic arc to postcollisional settings in the Permian; these plutons also involved the crystallization and differentiation of magmas from the mixing of mantle and crust (Fig. 12b).
(3) Late Permian-Triassic Late Permian strata are widely distributed in the Huhetaoergai arc zone (HZ) and the Zhusileng structural belt (ZZ) (Fig. 1) with similar lithology that represents continuous coastal, shallow-sea and marine-continental environments.From the perspective of regional evolution, the branch of the Paleo-Asian Ocean was closed before the Early Permian (283.2 ± 2.2 Ma), which is defined by the Yagan pluton in the northern part of the Alxa block [20] .
In this paper, two ages (220.5 Ma and 226.5 Ma) were measured in the Huhetaoergai pluton, which is the latest pluton we have found.Fig. 11 shows that the Huhetaoergai pluton formed in an extrusional environment, which indicates that the Huhetaoergai pluton represents an episode of intraplate evolution (Fig. 12c).The entire Huhetaoergai pluton underwent intensive orogenic movement in the Triassic, which led to mountain chain uplift and exhumation of subducted crust.Therefore, the Huhetaoergai pluton was in a compressional setting after a period of extensional postcollisional intraplate evolution, and the formation mechanism of the granites is related to crustal thickening in a compressional setting (Fig. 12c).

Conclusions
Based on zircon U-Pb dating, Sr-Nd-Hf isotope measurements, and major and trace element geochemistry of the Huhetaoergai granitoids in the northern Ya-Gan fault zone, together with other three studied granitoids (western Huhetaoergai, Zhuxiaogubuhe and Yagan), for which we collected previously published data, we can draw the following conclusions: 1) Zircon U-Pb dating yielded precise crystallization ages of 220.5 ± 1.9 Ma and 226.5 ± 2.4 Ma for the granitoids of the Huhetaoergai pluton in the northern Ya-Gan fault zone, which is the youngest pluton we have found in the area to date.
2) Most granitoids of the Huhetaoergai pluton are calc-alkaline to alkaline granodiorites and granites, which are similar to the rocks of the western Huhetaoergai, Zhuxiaogubuhe, and Yagan plutons.
3) The granitoids of the Huhetaoergai pluton are metaluminous to peraluminous, highly fractionated I-type granites, which are similar to the rocks of the western Huhetaoergai, Zhuxiaogubuhe, and Yagan plutons.for the magma in the northern Ya-Gan fault zone.However, the magmas of the granitoids in the western Huhetaoergai, Zhuxiaogubuhe, and Yagan plutons are products of the mixing of upper continental crust and asthenospheric materials.
5) The granitoids of the Huhetaoergai pluton were emplaced during an episode of intense intraplate orogenic movement evolution in an extrusional setting after a period of extensional postcollisional intraplate evolution, and the formation mechanism of the granites is related to crustal thickening in a compressional setting.(1985) [25] and Sun and McDonough (1989) [26], respectively.

Supplementary Materials
. Ltd., China.U-Pb dating analyses were conducted by laser ablation multicollector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) at the Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing.Detailed operating conditions for the laser ablation system and the MC-ICP-MS instrument and data reduction were the same as described by[8].Laser sampling was performed using a Newwave UP 213 laser ablation system.A Thermo Finnigan Neptune MC-ICP-MS instrument was used to acquire ion-signal intensities.The array of four multi-ion-counters and three faraday cups allowed simultaneous detection of 202Hg (on IC5), 204Hg, 204Pb (on IC4), 206Pb (on IC3), 207Pb (on IC2), 208Pb (on L4), 232Th (on H2), and 238U (on H4) ion signals.Helium was applied as the carrier gas.Argon was used as the make-up gas and mixed with the carrier gas via a T-connector before entering the ICP.Each analysis incorporated a background acquisition of approximately 20-30 s (gas blank) followed by 30 s of data acquisition from the sample.Off-line raw data selection, integration of background and analyte signals, time-drift correction and quantitative calibration for U-Pb dating were performed by ICP-MS-DataCal[9].

[ 21 ]
. The magmatism of the first stage produced the Neoproterozoic granites in the western Huhetaoergai pluton with an age of 889 ± 8 Ma, and these rocks are the oldest granites that crop out in this area.The second stage of magmatism involved an Early Carboniferous granodiorite with an age of 356 ± 3 Ma, which intruded into the Neoproterozoic granites.The third stage is marked by the formation of the Zhuxiaogubuhe pluton with an age of 286 ± 2 Ma, which is similar to the age of 283 ± Preprints (www.preprints.org)| NOT PEER-REVIEWED | Posted: 22 June 2018 doi:10.20944/preprints201806.0344.v1 2 Ma in the Yagan pluton.The ages of the Huhetaoergai pluton measured in this study are 220.5 ± 1.9 Ma and 226.5 ± 2.4 Ma, which might represent the last stage of magmatism in the northern Ya-Gan fault zone (Table ) Carboniferous-Early Permian The ocean represented by the Ya-Gan fault zone subducted northward and formed the Huhetaoergai volcanic arc in the Early Carboniferous when the Preprints (www.preprints.org)| NOT PEER-REVIEWED | Posted: 22 June 2018 doi:10.20944/preprints201806.0344.v1

Fig. 8 .
Fig. 8. Fractional crystallization vector diagrams for the samples taken fro the pluton

Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 22 June 2018 doi:10.20944/preprints201806.0344.v1
Exploration Technology Services Co.Ltd.Hebei Province, China.Rb and Sr were separated and purified using conventional cation exchange, whereas Sm and Nd were separated and purified using Teflon and a Power resin, respectively.The Sr-Nd isotope ratio correction for mass fractionation was undertaken by normalizing to86Sr/ 88 Sr = 0.1194 and 146 Nd/ 144 Nd = 0.7219.The 87 Sr/ 86 Sr ratio of the Sr standard [12] et al. (2002)3Nd/ 144 Nd ratio of the Nd standard (La Jolla) used in this study were 0.710249 ± 0.000012 (2σ) and 0.511869 ± 0.000006 (2s), respectively.The analytical accuracy of the Sr and Nd isotope data were better than 0.003%.Specific procedures for the isotope analytical techniques are given byChen et al. (2002)[12].

Table 3
63~15.05 and 15.84~40.85with averages of 11.90 and 29.11, respectively, which show properties of the crust.Additionally, the loss of Nb is obvious, and we can also rule out the properties of the crust.
26, i.e., <0.3, which reflects the characteristics of the continental crust components.The loss of Sr also indicates that the rock mass may be derived from the crust.The dilution of P originated in the mantle or crust.It is generally believed that the Nb/Ta and Zr/Hf values of mantle-derived rocks are approximately 17.5 and 36, respectively, while the Nb/Ta and Zr/Hf values of continental crust-derived rocks are approximately 11 and 33, respectively [25].The Nb/Ta and Zr/Hf of granites in the Huhetaoergai pluton are 8.

Table captions Table 1
LA-ICP-MS zircon U-Pb data of the granites in Huhetaoergai pluton

Table 2
Whole rock chemical compositions of the granite in Huhetaoergai pluton

Table 3
Whole rock Sr-Nd isotopic compositions

Table 4
The characteristic of different granitic plutons in the northern Ya-Gan fault zone

Table 5
Zircon Hf isotopic compositions of Ch08 and Yh22 from granites in

Table 6
CIPW standard mineral and petrochemical parameters calculation in the granites of Huhetaoergai pluton

Table 1
LA-ICP-MS zircon U-Pb data for the granites in the Huhetaoergai pluton

Table 4 .
The characteristic of different granitic plutons in the northern Ya-Gan fault zone

Table 5
Zircon Hf isotopic compositions for Ch08 and Yh22 from granites in the Huhetaoergai pluton .