Open access peer-reviewed chapter

Effectiveness for Determination of Depositional Age by Detrital Zircon U–Pb Age in the Cretaceous Shimanto Accretionary Complex of Japan

Written By

Tetsuya Tokiwa, Makoto Takeuchi, Yusuke Shimura, Kazuho Shobu, Akari Ota, Koshi Yamamoto and Hiroshi Mori

Submitted: June 29th, 2016 Reviewed: February 20th, 2017 Published: June 21st, 2017

DOI: 10.5772/67982

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Abstract

Detrital zircon U–Pb ages indicate the crystallization age. Therefore, it is necessary to evaluate the effectiveness of determining the age of deposition using zircon age data. We carried out U–Pb dating of detrital zircons from sandstone at eight sites in the Cretaceous Shimanto accretionary complex on Kii Peninsula, Japan, with the aim of evaluating the accuracy of U–Pb zircon ages as indicators of the depositional age of sedimentary rocks by comparing zircon ages with radiolarian ages. Our results reveal zircons of late Cretaceous age, and the youngest peak ages are in good agreement with depositional ages inferred from radiolarian fossils. In addition, the youngest peak ages become younger as tectono-structurally downwards, and this tendency is clearer for the zircon ages than for the radiolarian ages. These results indicate that newly crystalized zircons were continuously supplied to the sediment by constant igneous activity during the late Cretaceous and that zircon ages provide remarkably useful information for determining the age of deposition in the Cretaceous Shimanto accretionary complex.

Keywords

  • detrital zircon
  • U–Pb age
  • accretionary complex
  • Shimanto
  • Cretaceous

1. Introduction

Determination of the depositional age of sedimentary rocks is essential for understanding tectonic processes, and microfossils have generally been used for this purpose. In particular, radiolarian ages have been played an important role in understanding accretionary tectonics, because the order of accretion of strata is inferred from radiolarian ages (for example, see Refs. [1, 2]). However, it is very difficult to determine the depositional age of coarse-grained sedimentary rocks such as sandstone and conglomerate, because radiolarian fossils are rare in such rocks, whereas they are commonly found in fine-grained rocks such as mudstone and chert. In addition, it is impossible to identify the species of radiolarian fossils in metamorphosed sedimentary rocks.

Recent progress in analytical techniques has enabled rapid and accurate U–Pb isotopic age determination of zircons using inductively coupled plasma–mass spectrometry with laser ablation sampling (LA–ICP–MS) (for example, see Refs. [3, 4]). This method has been widely used to determine zircon ages in coarse-grained and weakly metamorphosed sedimentary rock (for example, see Refs. [57]). However, zircon ages do not directly indicate the depositional age; instead, they indicate the crystallization age. Thus, it is possible that a large age gap exists between the depositional ages and zircon ages. Therefore, to determine the depositional age from detrital zircon U–Pb ages, it is necessary to evaluate the effectiveness of this method; e.g., by comparing detrital zircon ages with fossil ages.

In this study, we performed U–Pb dating on detrital zircons from sandstone in the Cretaceous Shimanto accretionary complex on Kii Peninsula, Japan, and we clarify the relationship between the detrital zircon ages and radiolarian ages in order to develop the zircon dating method to obtain accurate depositional ages.

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2. Geological setting

The Shimanto accretionary complex is a well-studied ancient accretionary complex exposed along the Pacific side of Southwest Japan (for example, see Ref. [1]). The Shimanto accretionary complex in the Kii Peninsula is divided into the Kouyasan Sub-belt (Cretaceous), the Hidakagawa Sub-belt (Cretaceous) and the Hikigawa Sub-belt (Paleogene) (Figure 1; [8]). This study considers the Yukawa complex (Albian–Cenomanian), Miyama complex (Turonian–Campanian) and Ryujin complex (Campanian–Maastrichtian) in the Hidakagawa Sub-belt. These complexes are further subdivided into several units, and these complexes and units are in thrust contact with each other [8]. The unit names are shown in Figure 2. Many radiolarian studies have been carried out in this study area [917], and the results indicate that the depositional ages have a tendency to become younger as tectono-structurally downwards (north to south).

Figure 1.

Geological distribution of the Shimanto accretionary complex, Kii Peninsula, southwest Japan. (Modified form Kishu Shimanto Research Group [8].) Sampling sites for zircon U–Pb dating are shown in this figure. Yu1: Yanase Unit, Yu2: Kitamata Unit, M1: Chikai Unit, M2: Gomadanzan Unit, M3: Hattomaki Unit, M4: Ubuyukawa Unit, Ry1: Sohgawa Unit, Ry2: Komatagawa Unit, and Ry3: Yunohara Unit.

Figure 2.

Relationship between tectono-structural division and sampling site. (Division is modified form the Kishu Shimanto Research Group [8]).

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3. Samples

Sandstone samples for U–Pb dating were collected from eight sites. The sites were named Site 1 to Site 8 from tectono-structurally upwards to downwards (north to south), and the relationship between sampling sites and geological units is shown in Figure 2.

Site 1 (sample no. 150503-06): This sample was collected from a medium-grained massive sandstone of the Yanase unit (Yu1), Yukawa complex (GPS: N34°6′13.28″, E135°30′32.82″) (Figures 3a and 4a). The sandstone is composed of quartz (23.3%), plagioclase (27.3%), K-feldspar (8.6%), rock fragments (15.9%), matrix (17.1%) and the others (7.8%) (Figure 5).

Figure 3.

Photographs showing the occurrence of the sandstone at the Site 1 in the Yu1 of the Yukawa Complex (a), Site 3 in the M1 of the Miyama Complex (b), and Site 7 in the Ry2 of the Ryujin Complex (c).

Figure 4.

Photomicrograph of the sandstone at the Site 1 in the Yu1 of the Yukawa Complex (a), Site 3 in the M1 of the Miyama Complex (b), and Site 7 in the Ry2 of the Ryujin Complex (c). Sandstone under crossed polarized light.

Figure 5.

Modal composition of sandstones in the each site. Closed lines show the confidence regions of 90% in each of the complexes. (Modified form Kumon et al. [18].)

Site 2 (sample no. 151014-02): This sample was collected from a medium-grained massive sandstone of the Kitamata unit (Yu2), Yukawa complex (GPS: N34°7′32.36″, E135°38′32.48″). The sandstone is composed of quartz (29.9%), plagioclase (32.1%), K-feldspar (9.4%), rock fragments (17.9%), matrix (10.3%) and the others (0.4%).

Site 3 (sample no. 160705-06): This sample was collected from a medium-grained massive sandstone of the Chikai unit (M1), Miyama complex (GPS: N34°3′22.37″, E135°28′47.3″) (Figures 3b and 4b). The sandstone is composed of quartz (29.1%), plagioclase (13.9%), K-feldspar (11.0%), rock fragments (26.2%), matrix (16.5%) and the others (3.3%).

Site 4 (sample no.160705-02): This sample was collected from a medium-grained massive sandstone of the Gomadanzan unit (M2), Miyama complex (GPS: N34°1′8.81″, E135°25′41.19″). The sandstone is composed of quartz (25.3%), plagioclase (16.7%), K-feldspar (9.4%), rock fragments (23.6%), matrix (23.2%) and the others (1.8%).

Site 5 (sample no.160705-01): This sample was collected from a medium-grained massive sandstone in the Hattomaki unit of (M3), Miyama complex (GPS: N33°59′4.15″, E135°24′40.99″). The sandstone is composed of quartz (28.9%), plagioclase (17.3%), K-feldspar (11.1%), rock fragments (21.3%), matrix (18.2%) and the others (3.2%).

Site 6 (sample no.160704-05): This sample was collected from a medium-grained sandstone of the alternating beds of sandstone and mudstone in the Sohgawa unit (Ry1), Ryujin complex (GPS: N33°59′3.65″, E135°33′23.67″). The sandstone is composed of quartz (25.0%), plagioclase (19.9%), K-feldspar (8.5%), rock fragments (18.6%), matrix (19.9%) and the others (8.1%).

Site 7 (sample no. 160704-04): This sample was collected from a medium-grained sandstone of the alternating beds of sandstone and mudstone in the Komatagawa unit (Ry2), Ryujin complex (GPS: N33°57′35.99″, E135°33′50.36″) (Figures 3c and 4c). The sandstone is composed of quartz (25.9%), plagioclase (23.0%), K-feldspar (11.1%), rock fragments (16.5%), matrix (19.3%) and the others (4.2%).

Site 8 (sample no. 160704-03): This sample was collected from a medium-grained sandstone of the alternating beds of sandstone and mudstone in the Yunohara unit (Ry3), Ryujin complex (GPS: N33°53′42.86″, E135°29′40.63″). The sandstone is composed of quartz (29.7%), plagioclase (17.8%), K-feldspar (8.1%), rock fragments (16.1%), matrix (19.5%) and the others (8.8%).

On ternary composition diagrams, the compositions of all the sandstones samples, within the 90% confidence region of the modal composition of each complex (Figure 5; [18]).

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4. Analytical techniques

Zircons were separated by conventional techniques including crushing, sieving, water-based panning and magnetic separation. Zircons were randomly handpicked under a stereoscopic microscope, mounted in epoxy resin on a glass slide, and polished to approximately half of their original thickness. In order to investigate the internal structure and zonation patterns of zircons, cathodoluminescence (CL) images were obtained using a scanning electron microscope (SEM) JSM-6510 (JOEL Ltd) at Shinshu University of Japan. Target spots for U–Pb dating analyses were identified from the CL images (Figure 6).

Figure 6.

Cathodoluminescence images of selected zircon grains. (a) Site 1 in the Yu1, grain no. Yu-041. (b) Site 2 in the Yu2, grain no. Yu2-095. (c) Site 3 in the M1, grain no. M1-046. (d) Site 4 in the M2, grain no. M2-003. (e) Site 5 in the M3, grain no. M3-018. (f) Site 6 in the Ry1, grain no. Ry1-022. (g) Site 7 in the Ry2, grain no. Ry2-037. (h) Site 8 in the Ry3, grain no. Ry3-021. Scale bars are 50 μm. Ages indicate 238U– 206Pb ages in Ma.

The U–Pb zircon dating analyses carried out using a laser ablation–inductively coupled plasma mass spectrometer (LA–ICP–MS) at Nagoya University of Japan. The ICP–MS part is Agilent 7700x (Agilent Technologies), and the LA part is NWR213 (Electro Scientific Industries). Nancy zircon 91500 [19] was utilized for normalization of NIST SRM 610, and the latter was used as the external standard for age determinations. Analyses were carried out with an ablation pit size of 25 μm, energy density of 11.7 J/cm2 and pulse repetition rate of 10 Hz. Detailed descriptions of the LA–ICP–MS analysis are provided by Orihashi et al. [20] and Kouchi et al. [21].

In order to obtain accurate age data, we deleted the missed shot spot that is indicative of an anomalous value. In addition, based on the judgment of discordance showed by the many previous studies (for example, see Refs. [2224]), the U–Pb zircon ages with discordances of >10% were rejected in data interpretation in this paper. Age calculations were performed using Isoplot/Ex 4.15 [25]. All ages indicate the 238U–206Pb ages, and uncertainties are given at the 2σ level.

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5. Zircon U–Pb ages

Analyses were carried out on more than 160 spots in each sample. Results are shown in histograms and probability density plots (Figures 7 and 8). The probability density plots show the cumulative Gaussian probability curve for a collection of single-valued data and errors [25]. All data are shown in the Appendix.

Figure 7.

Histogram and probability density plot of Site 1 to Site 4. Left side and right side diagrams show all data and 0–400 Ma data, respectively.

Figure 8.

Histogram and probability density plot of Site 5 to Site 8. Left side and right side diagrams show all data and 0–400 Ma data, respectively.

Site 1 (sample no. 150503-06): 200 spots on 200 zircon grains were analysed, and 142 spots (discordances of <10%) were selected for statistical interpretations. The zircon U–Pb ages consist mainly of two age groups; ca. 90–320 Ma (66%) and ca. 1500–2600 Ma (31%). The youngest age is 98.8 ± 2.5 Ma, and the highest peak age on the probability density plot is at ca. 190 Ma. The zircons that yield ages of ca. 1500–2600 Ma are rounded and they show distinct cores and rims in the CL images (Figure 6a). The other zircons are euhedral and exhibit clear oscillatory zoning.

Site 2 (sample no. 151014-02): 200 spots on 200 zircon grains were analysed, and 140 spots (discordances of <10%) were selected for statistical interpretations. The zircon U–Pb ages consist mainly of two age groups: ca. 100–310 Ma (62%) and ca. 1500–2500 Ma (36%). The youngest age is 100.1 ± 2.8 Ma and the highest peak age on the probability density plot is at ca. 178 Ma. The zircons that yield ages of ca. 1500–2500 Ma are rounded and they show distinct cores and rims in the CL images (Figure 6b). The other zircons are euhedral and show clear oscillatory zoning.

Site 3 (sample no. 160705-06): 180 spots on 180 zircon grains were analysed, and 86 spots (discordances of <10%) were selected for statistical interpretations. The zircon U–Pb ages consist mainly of one age group at ca. 80–140 Ma (91%). The youngest age is 85.6 ± 3.4 Ma and the highest peak age on the probability density plot is at ca. 100 Ma. Most of the zircons are euhedral and display clear oscillatory zoning (Figure 6c).

Site 4 (sample no. 160705-02): 180 spots on 180 zircon grains were analysed, and 78 spots (discordances of <10%) were selected for statistical interpretations. The zircon U–Pb ages consist mainly of one age group at ca. 70–130 Ma (88%). The youngest age is 75 ± 2.9 Ma and the highest peak age on the probability density plot is at ca. 98 Ma. Most of the zircons are euhedral and exhibit clear oscillatory zoning (Figure 6d).

Site 5 (sample no.160705-01): 180 spots on 174 zircon grains were analysed, and 119 spots (discordances of <10%) were selected for statistical interpretations. The zircon U–Pb ages consist mainly of three age groups at ca. 70–110 Ma (7%), ca. 160–240 Ma (17%), and ca. 1300–2600 Ma (74%). The youngest age is 77.3 ± 2.1 Ma and the highest peak age on the probability density plot is at ca. 184 Ma. The zircons that yield ages of ca. 1300–2600 Ma are rounded and show cores and rims (Figure 6e). The other zircons are euhedral and display clear oscillatory zoning.

Site 6 (sample no.160704-05): 180 spots on 180 zircon grains were analysed, and 42 spots (discordances of <10%) were selected for statistical interpretations. The zircon U–Pb ages consist mainly of one age group at ca. 60–120 Ma (79%). The youngest age is 62.9 ± 5.7 Ma and the highest peak age on the probability density plot is at ca. 86 Ma. Most of the zircons are euhedral and indicate show clear oscillatory zoning (Figure 6f).

Site 7 (sample no. 160704-04): 180 spots on 180 zircon grains were analysed, and 58 spots (discordances of <10%) were selected for statistical interpretations. The zircon U–Pb ages consist mainly of one age group at ca. 60–120 Ma (78%). The youngest age is 62 ± 8.4 Ma and the highest peak age on the probability density plot is at ca. 67 Ma. Most of the zircons are euhedral and exhibit clear oscillatory zoning (Figure 6g).

Site 8 (sample no. 160704-03): 180 spots on 180 zircon grains were analysed, and 43 spots (discordances of <10%) were selected for statistical interpretations. The zircon U–Pb ages consist mainly of one age group at ca. 60–120 Ma (72%). The youngest age is 62.7 ± 2.1 Ma and the highest peak age on the probability density plot is at ca. 84 Ma. Most of the zircons are euhedral and display clear oscillatory zoning (Figure 6h).

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6. Relationship between detrital zircon U–Pb age and radiolarian fossil age

In this paper, we have not used the youngest single age but the youngest peak age in comparing detrital zircon U–Pb ages with radiolarian fossil ages because it is possible that the zircon U–Pb ages indicate younger than the crystallization age as a result of lead loss [26]. We applied the ‘mixture modelling’ proposed by Sambridge and Compston [27] to determine the youngest peak age. The ‘mixture modelling’ is in common usage in estimating the youngest peak age (for example, see Refs. [2830]). The results indicate that the youngest peak ages are 100.8 ± 1.7 Ma (fraction = 0.09) at Site 1 (Yu1), 100.2 ± 2.9 Ma (fraction = 0.13) at Site 2 (Yu2), 88.0 ± 1.1 Ma (fraction = 0.13) at Site 3 (M1), 82.2 ± 1.1 Ma (fraction = 0.15) at Site 4 (M2), 78.3 ± 1.7 Ma (fraction = 0.37) at Site 5 (M3), 69.9 ± 1.5 Ma (fraction = 0.12) at Site 6 (Ry1), 66.9 ± 1.1 Ma (fraction = 0.27) at Site 7 Ry2) and 67.8 ± 0.78 Ma (fraction = 0.26) at Site 8 (Ry3).

Radiolarian fossils indicate Albian to Cenomanian ages for Yu1 and Yu2 [9, 11], Turonian to Coniacian ages for M1 [9, 11], Santonian to early Campanian ages for M2 and M3 [9], late Campanian to middle Maastrichtian ages for Ry1 (Figure 9; [10, 13, 14, 16, 17]). In Ry2 and Ry3, the radiolarian fossils indicate a late Campanian age [15]; however, a previous study point out the possibility that Ry2 and Ry3 contain radiolarian fossils of middle Maastrichtian age [12].

Figure 9.

Summary of age distribution of U–Pb zircon ages and radiolarian ages. See text for the radiolarian ages of the each unit.

Detrital zircon U–Pb ages are in good agreement with depositional ages inferred from radiolarian fossils (Figure 9). In addition, the youngest peak ages become younger as tectono-structurally downwards; this trend is clearer in the U–Pb ages than in the radiolarian ages. In general, the detrital zircon U–Pb ages do not directly indicate the depositional age, because the ages indicate their crystallization ages. However, igneous activity occurred continuously during the late Cretaceous along the Eastern Asian continental margin where the proto-Japan arc was situated (for example, see Refs. [3133]). In addition, it is reported that the sandstone compositions of the Cretaceous Shimanto accretionary complex provide evidence for the igneous activity (for example, see Refs. [18, 34, 35]). Most of detrital zircons of Cretaceous age from this study exhibit clear oscillatory zonings. Such zoning reflects crystal growth in a magma chamber, and the zoning is commonly altered to other structure such as core–rim textures and homogeneous textures as the result of metamorphism-induced recrystallization and hydrothermal alteration [36]. Therefore, these detrital Cretaceous zircons in this study are of igneous origin. Thus, it is considered that newly crystallized zircons were continuously supplied by constant igneous activity during the late Cretaceous period, which led to the concordance between the depositional age and zircon age.

From above, we can conclude that detrital zircon U–Pb ages can provide remarkably useful information for determining of the depositional age in the Cretaceous Shimanto accretionary complex.

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7. Conclusions

Detrital zircons from sandstone in the Cretaceous Shimanto accretionary complex were subjected to U–Pb dating. The youngest peak ages in the samples from tectono-structurally upwards to downwards were 100.8 ± 1.7 Ma, 100.2 ± 2.9 Ma, 88.0 ± 1.1 Ma, 82.2 ± 1.1 Ma, 78.3 ± 1.7 Ma, 69.9 ± 1.5 Ma, 66.9 ± 1.1 Ma and 67.8 ± 0.78 Ma. These youngest peak ages are in good agreement with the depositional ages inferred from radiolarian fossils. In addition, the youngest peak ages become younger as tectono-structurally downwards. This trend is clearer in the U–Pb age data than in the radiolarian age data and is typical of an accretionary complex. Therefore, U–Pb dating of detrital zircons in sandstone is an effective way to determine the depositional age of strata in the Cretaceous Shimanto accretionary complex.

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Acknowledgments

This study was partially supported by a grant from the Fukada Geological Institute (Fukada Grant-in-Aid, 2015). Constructive review comments by Y. Itoh greatly improved the manuscript.

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Grain No.206Pb/238U207Pb/235U238U–206Pb age (Ma)235U–207Pb age (Ma)Th/UGrain No.206Pb/238U207Pb/235U238U–206Pb age (Ma)235U–207Pb age (Ma)Th/U
Site 1 (Sample 150503-06) in Yanase Unit (Yu1) of Yukawa ComplexYu1-0860.02259 ± 0.000440.1524 ± 0.0095144.0 ± 2.8144.0 ± 9.01.46
Yu1-0010.29308 ± 0.006754.5101 ± 0.15051656.9 ± 38.21732.8 ± 57.80.22Yu1-0870.35608 ± 0.005885.6450 ± 0.17251963.6 ± 32.41922.9 ± 58.70.43
Yu1-0020.34581 ± 0.008935.2821 ± 0.24851914.6 ± 49.51865.9 ± 87.81.32Yu1-0880.03080 ± 0.000700.2042 ± 0.0170195.6 ± 4.4188.6 ± 15.70.52
Yu1-0030.30564 ± 0.006924.7023 ± 0.14461719.2 ± 38.91767.6 ± 54.30.24Yu1-0890.03006 ± 0.000540.2074 ± 0.0101190.9 ± 3.4191.4 ± 9.30.22
Yu1-0040.03773 ± 0.000950.2675 ± 0.0163238.8 ± 6.0240.7 ± 14.70.55Yu1-0900.04459 ± 0.001270.3274 ± 0.0171281.2 ± 8.0287.6 ± 15.00.55
Yu1-0050.01834 ± 0.000530.1319 ± 0.0119117.2 ± 3.4125.8 ± 11.30.37Yu1-0910.40599 ± 0.011168.2032 ± 0.28642196.6 ± 60.42253.6 ± 78.71.06
Yu1-0060.37125 ± 0.008406.5750 ± 0.19932035.3 ± 46.12055.9 ± 62.30.10Yu1-0920.33660 ± 0.010085.2328 ± 0.27331870.3 ± 56.01857.9 ± 97.00.78
Yu1-0070.04174 ± 0.001120.3220 ± 0.0224263.6 ± 7.1283.5 ± 19.70.38Yu1-0930.01801 ± 0.000570.1327 ± 0.0111115.1 ± 3.7126.5 ± 10.61.23
Yu1-0080.03643 ± 0.000940.2475 ± 0.0143230.7 ± 6.0224.6 ± 13.00.78Yu1-0940.04283 ± 0.001280.3119 ± 0.0206270.3 ± 8.1275.7 ± 18.20.70
Yu1-0090.01851 ± 0.000670.1359 ± 0.0178118.2 ± 4.3129.4 ± 16.90.43Yu1-0950.02943 ± 0.005320.2034 ± 0.0387187.0 ± 33.8188.0 ± 35.80.40
Yu1-0100.35598 ± 0.008835.5068 ± 0.23131963.1 ± 48.71901.6 ± 79.90.17Yu1-0960.15109 ± 0.027291.6411 ± 0.3016907.1 ± 163.9986.1 ± 181.20.25
Yu1-0110.03426 ± 0.001170.2247 ± 0.0274217.2 ± 7.4205.8 ± 25.10.65Yu1-0970.02644 ± 0.004780.1850 ± 0.0350168.2 ± 30.4172.3 ± 32.60.21
Yu1-0120.31714 ± 0.008714.9983 ± 0.27121775.8 ± 48.81819.0 ± 98.70.63Yu1-0980.02783 ± 0.005040.2003 ± 0.0383176.9 ± 32.0185.4 ± 35.40.91
Yu1-0130.03570 ± 0.001200.2509 ± 0.0286226.1 ± 7.6227.3 ± 25.90.29Yu1-0990.03132 ± 0.005670.2146 ± 0.0408198.8 ± 36.0197.4 ± 37.60.39
Yu1-0140.01836 ± 0.002580.1258 ± 0.0272117.3 ± 16.5120.3 ± 26.00.51Yu1-1000.02617 ± 0.004740.1800 ± 0.0347166.5 ± 30.1168.0 ± 32.40.57
Yu1-0150.33863 ± 0.047015.4033 ± 1.00761880.1 ± 261.01885.3 ± 351.60.27Yu1-1010.05890 ± 0.010650.4458 ± 0.0830368.9 ± 66.7374.3 ± 69.70.55
Yu1-0160.04315 ± 0.006020.3141 ± 0.0619272.3 ± 38.0277.3 ± 54.60.36Yu1-1020.02856 ± 0.000920.1962 ± 0.0110181.5 ± 5.8181.9 ± 10.20.33
Yu1-0170.28236 ± 0.039214.4232 ± 0.82561603.2 ± 222.61716.6 ± 320.40.13Yu1-1030.32550 ± 0.010245.6463 ± 0.24001816.6 ± 57.21923.1 ± 81.70.14
Yu1-0180.46045 ± 0.0640410.6060 ± 1.99252441.5 ± 339.62489.1 ± 467.60.40Yu1-1040.36460 ± 0.011445.6560 ± 0.23812003.9 ± 62.91924.6 ± 81.00.21
Yu1-0190.29075 ± 0.040404.6481 ± 0.87101645.3 ± 228.61757.9 ± 329.40.30Yu1-1050.01937 ± 0.000750.1425 ± 0.0162123.7 ± 4.8135.2 ± 15.30.89
Yu1-0200.03105 ± 0.004350.2244 ± 0.0468197.1 ± 27.6205.6 ± 42.90.48Yu1-1060.02620 ± 0.000830.1786 ± 0.0091166.7 ± 5.3166.8 ± 8.50.79
Yu1-0210.02130 ± 0.000550.1329 ± 0.0094135.8 ± 3.5126.7 ± 8.90.82Yu1-1070.41387 ± 0.009217.7769 ± 0.25512232.6 ± 49.72205.5 ± 72.40.71
Yu1-0220.03934 ± 0.001170.2624 ± 0.0263248.7 ± 7.4236.6 ± 23.80.42Yu1-1080.02493 ± 0.000600.1770 ± 0.0093158.7 ± 3.8165.5 ± 8.70.42
Yu1-0230.28086 ± 0.006484.2625 ± 0.14591595.7 ± 36.81686.1 ± 57.70.61Yu1-1090.02608 ± 0.000760.1816 ± 0.0156166.0 ± 4.8169.4 ± 14.50.71
Yu1-0240.32488 ± 0.007325.1435 ± 0.15351813.5 ± 40.81843.3 ± 55.00.14Yu1-1100.04332 ± 0.001240.3020 ± 0.0248273.4 ± 7.8268.0 ± 22.01.64
Yu1-0250.01912 ± 0.000560.1386 ± 0.0131122.1 ± 3.6131.8 ± 12.50.55Yu1-1110.01928 ± 0.000540.1380 ± 0.0103123.1 ± 3.4131.2 ± 9.80.84
Yu1-0260.34328 ± 0.007756.8643 ± 0.20421902.4 ± 42.92094.0 ± 62.30.30Yu1-1120.48029 ± 0.0129010.6520 ± 0.33902528.5 ± 67.92493.2 ± 79.40.71
Yu1-0270.02191 ± 0.000480.1451 ± 0.0123139.7 ± 3.0137.6 ± 11.70.65Yu1-1130.40824 ± 0.010888.6211 ± 0.26642206.9 ± 58.82298.7 ± 71.00.15
Yu1-0280.14017 ± 0.002621.3545 ± 0.0770845.6 ± 15.8869.5 ± 49.40.26Yu1-1140.02075 ± 0.000670.1535 ± 0.0138132.4 ± 4.3145.0 ± 13.00.53
Yu1-0290.04021 ± 0.000620.2900 ± 0.0117254.1 ± 3.9258.5 ± 10.40.81Yu1-1150.40300 ± 0.011057.2154 ± 0.25652182.8 ± 59.82138.3 ± 76.00.72
Yu1-0300.03881 ± 0.000630.2780 ± 0.0131245.4 ± 4.0249.0 ± 11.80.70Yu1-1160.04410 ± 0.001570.3287 ± 0.0262278.2 ± 9.9288.5 ± 23.00.47
Yu1-0310.03343 ± 0.000640.2430 ± 0.0161212.0 ± 4.1220.9 ± 14.60.43Yu1-1170.02962 ± 0.000790.2079 ± 0.0121188.2 ± 5.0191.8 ± 11.20.24
Yu1-0320.03529 ± 0.001030.2489 ± 0.0303223.6 ± 6.5225.7 ± 27.50.44Yu1-1180.02726 ± 0.000790.1952 ± 0.0127173.4 ± 5.0181.0 ± 11.70.34
Yu1-0330.04460 ± 0.001090.3061 ± 0.0266281.3 ± 6.9271.1 ± 23.50.46Yu1-1190.03759 ± 0.001420.2654 ± 0.0227237.9 ± 9.0239.0 ± 20.41.30
Yu1-0340.04953 ± 0.001690.3975 ± 0.0542311.6 ± 10.6339.9 ± 46.40.40Yu1-1200.29430 ± 0.006474.4864 ± 0.14741663.0 ± 36.51728.4 ± 56.80.11
Yu1-0350.01817 ± 0.000560.1126 ± 0.0150116.1 ± 3.6108.4 ± 14.40.47Yu1-1210.01976 ± 0.000980.1302 ± 0.0138126.2 ± 6.3124.3 ± 13.10.45
Yu1-0360.04902 ± 0.001070.3934 ± 0.0257308.5 ± 6.7336.8 ± 22.00.24Yu1-1220.45026 ± 0.020779.0129 ± 0.48662396.4 ± 110.52339.2 ± 126.30.46
Yu1-0370.03767 ± 0.000920.2814 ± 0.0235238.4 ± 5.8251.8 ± 21.10.63Yu1-1230.36066 ± 0.016605.8082 ± 0.31141985.3 ± 91.41947.6 ± 104.40.18
Yu1-0380.33022 ± 0.012755.8938 ± 0.34281839.5 ± 71.01960.3 ± 114.00.12Yu1-1240.04334 ± 0.001330.3122 ± 0.0254273.5 ± 8.4275.9 ± 22.40.67
Yu1-0390.29209 ± 0.019664.6595 ± 0.45781651.9 ± 111.21759.9 ± 172.90.42Yu1-1250.38653 ± 0.010406.0288 ± 0.26742106.7 ± 56.71979.9 ± 87.80.20
Yu1-0400.03799 ± 0.000810.2703 ± 0.0138240.3 ± 5.1242.9 ± 12.40.82Yu1-1260.37922 ± 0.010926.0652 ± 0.33302072.6 ± 59.71985.2 ± 109.00.67
Yu1-0410.41540 ± 0.008437.6183 ± 0.26212239.6 ± 45.52186.9 ± 75.20.53Yu1-1270.30472 ± 0.008174.9258 ± 0.21571714.7 ± 46.01806.6 ± 79.10.19
Yu1-0420.02020 ± 0.000530.1384 ± 0.0120128.9 ± 3.4131.6 ± 11.40.55Yu1-1280.02287 ± 0.000870.1675 ± 0.0223145.8 ± 5.6157.2 ± 21.00.77
Yu1-0430.33439 ± 0.006825.8951 ± 0.20731859.6 ± 37.91960.4 ± 68.90.85Yu1-1290.44038 ± 0.011899.4131 ± 0.41752352.3 ± 63.52379.0 ± 105.50.81
Yu1-0440.35117 ± 0.006905.4899 ± 0.17161940.2 ± 38.11898.9 ± 59.40.39Yu1-1300.03684 ± 0.001110.2702 ± 0.0210233.2 ± 7.0242.8 ± 18.90.54
Yu1-0450.03749 ± 0.001240.2875 ± 0.0353237.3 ± 7.9256.6 ± 31.50.53Yu1-1310.03704 ± 0.000560.2709 ± 0.0139234.4 ± 3.6243.4 ± 12.51.21
Yu1-0460.02987 ± 0.001280.2137 ± 0.0140189.8 ± 8.1196.7 ± 12.90.16Yu1-1320.03232 ± 0.000510.2238 ± 0.0124205.1 ± 3.2205.1 ± 11.40.47
Yu1-0470.03435 ± 0.001470.2399 ± 0.0162217.7 ± 9.3218.3 ± 14.70.51Yu1-1330.02941 ± 0.000450.2089 ± 0.0110186.9 ± 2.9192.7 ± 10.10.25
Yu1-0480.02971 ± 0.001300.2194 ± 0.0174188.7 ± 8.3201.4 ± 15.90.26Yu1-1340.01604 ± 0.000360.1128 ± 0.0105102.6 ± 2.3108.5 ± 10.11.39
Yu1-0490.03771 ± 0.001640.2595 ± 0.0197238.6 ± 10.4234.2 ± 17.80.62Yu1-1350.36392 ± 0.004395.7826 ± 0.13542000.7 ± 24.11943.7 ± 45.50.21
Yu1-0500.02956 ± 0.001490.2023 ± 0.0291187.8 ± 9.5187.0 ± 26.90.49Yu1-1360.02008 ± 0.000580.1388 ± 0.0177128.2 ± 3.7132.0 ± 16.91.32
Yu1-0510.02731 ± 0.000520.1961 ± 0.0115173.7 ± 3.3181.8 ± 10.60.72Yu1-1370.02618 ± 0.000340.1794 ± 0.0069166.6 ± 2.2167.5 ± 6.40.36
Yu1-0520.02997 ± 0.000750.2045 ± 0.0196190.4 ± 4.8188.9 ± 18.10.53Yu1-1380.33782 ± 0.011195.1525 ± 0.31541876.2 ± 62.21844.7 ± 112.90.21
Yu1-0530.33314 ± 0.005265.3443 ± 0.14031853.6 ± 29.31875.9 ± 49.20.25Yu1-1390.04484 ± 0.001610.3597 ± 0.0313282.7 ± 10.1312.0 ± 27.10.60
Yu1-0540.01974 ± 0.000580.1343 ± 0.0160126.0 ± 3.7127.9 ± 15.30.85Yu1-1400.03036 ± 0.001110.2023 ± 0.0200192.8 ± 7.1187.1 ± 18.50.28
Yu1-0550.03344 ± 0.000850.2207 ± 0.0219212.0 ± 5.4202.5 ± 20.10.57Yu1-1410.02922 ± 0.000990.1980 ± 0.0146185.7 ± 6.3183.4 ± 13.50.31
Yu1-0560.33998 ± 0.005575.3254 ± 0.15531886.6 ± 30.91872.9 ± 54.60.24Yu1-1420.03201 ± 0.001280.2190 ± 0.0273203.1 ± 8.1201.1 ± 25.10.31
Yu1-0570.02363 ± 0.000830.1679 ± 0.0189150.6 ± 5.3157.6 ± 17.81.57Site 2 (Sample 151014-02) in Kitamata Unit (Yu2) of Yukawa Complex
Yu1-0580.04092 ± 0.001250.2635 ± 0.0216258.5 ± 7.9237.5 ± 19.50.72Yu2-0010.33832 ± 0.005905.2966 ± 0.15201878.6 ± 32.81868.3 ± 53.60.20
Yu1-0590.03644 ± 0.001050.2855 ± 0.0171230.7 ± 6.6255.0 ± 15.30.40Yu2-0020.35570 ± 0.006205.5867 ± 0.15981961.7 ± 34.21914.0 ± 54.70.57
Yu1-0600.36254 ± 0.009675.7486 ± 0.18971994.2 ± 53.21938.6 ± 64.00.34Yu2-0030.03432 ± 0.000820.2325 ± 0.0194217.5 ± 5.2212.2 ± 17.70.34
Yu1-0610.03201 ± 0.001110.2158 ± 0.0247203.1 ± 7.1198.4 ± 22.70.84Yu2-0040.03113 ± 0.000820.2276 ± 0.0218197.6 ± 5.2208.2 ± 19.90.39
Yu1-0620.02243 ± 0.000820.1583 ± 0.0197143.0 ± 5.2149.3 ± 18.61.35Yu2-0050.03666 ± 0.000780.2574 ± 0.0164232.1 ± 5.0232.5 ± 14.80.30
Yu1-0630.02852 ± 0.000610.2017 ± 0.0109181.3 ± 3.9186.5 ± 10.10.37Yu2-0060.03179 ± 0.000910.2020 ± 0.0231201.7 ± 5.8186.8 ± 21.40.91
Yu1-0640.01544 ± 0.000380.1101 ± 0.008798.8 ± 2.5106.0 ± 8.41.55Yu2-0070.01798 ± 0.000420.1218 ± 0.0096114.8 ± 2.7116.7 ± 9.20.39
Yu1-0650.02914 ± 0.000590.2053 ± 0.0090185.2 ± 3.8189.6 ± 8.30.40Yu2-0080.30263 ± 0.005644.6860 ± 0.15881704.3 ± 31.81764.7 ± 59.80.54
Yu1-0660.03651 ± 0.000890.2677 ± 0.0200231.2 ± 5.6240.9 ± 18.00.63Yu2-0090.02842 ± 0.000580.1942 ± 0.0112180.6 ± 3.7180.2 ± 10.40.18
Yu1-0670.01792 ± 0.000560.1253 ± 0.0147114.5 ± 3.6119.9 ± 14.10.90Yu2-0100.03316 ± 0.000930.2142 ± 0.0235210.3 ± 5.9197.0 ± 21.60.60
Yu1-0680.03020 ± 0.000660.2118 ± 0.0122191.8 ± 4.2195.1 ± 11.20.41Yu2-0110.32489 ± 0.005765.0978 ± 0.14881813.6 ± 32.11835.7 ± 53.60.16
Yu1-0690.02882 ± 0.000860.2142 ± 0.0165183.1 ± 5.4197.1 ± 15.20.44Yu2-0120.39869 ± 0.007438.1638 ± 0.26402163.0 ± 40.32249.3 ± 72.70.59
Yu1-0700.02803 ± 0.000760.1966 ± 0.0107178.2 ± 4.9182.2 ± 9.90.12Yu2-0130.02781 ± 0.000570.1894 ± 0.0109176.8 ± 3.6176.1 ± 10.10.11
Yu1-0710.34981 ± 0.009076.6285 ± 0.23771933.7 ± 50.22063.1 ± 74.00.17Yu2-0140.03043 ± 0.000840.2118 ± 0.0217193.2 ± 5.3195.0 ± 20.00.39
Yu1-0720.03185 ± 0.000910.2468 ± 0.0164202.1 ± 5.8223.9 ± 14.90.64Yu2-0150.03922 ± 0.001600.2920 ± 0.0329248.0 ± 10.1260.1 ± 29.30.62
Yu1-0730.35782 ± 0.009455.6855 ± 0.22381971.8 ± 52.11929.1 ± 75.90.36Yu2-0160.34878 ± 0.011906.6032 ± 0.29861928.8 ± 65.82059.7 ± 93.10.41
Yu1-0740.03027 ± 0.000840.2128 ± 0.0129192.2 ± 5.4195.9 ± 11.90.19Yu2-0170.35085 ± 0.011946.5776 ± 0.29441938.7 ± 66.02056.3 ± 92.00.34
Yu1-0750.33721 ± 0.008855.9032 ± 0.22391873.2 ± 49.21961.6 ± 74.40.47Yu2-0180.02964 ± 0.001050.1987 ± 0.0131188.3 ± 6.7184.0 ± 12.10.20
Yu1-0760.03619 ± 0.001100.2845 ± 0.0241229.2 ± 7.0254.3 ± 21.50.56Yu2-0190.02811 ± 0.001060.1926 ± 0.0171178.7 ± 6.7178.8 ± 15.90.46
Yu1-0770.02847 ± 0.000780.1858 ± 0.0120180.9 ± 5.0173.0 ± 11.10.24Yu2-0200.03045 ± 0.000880.1953 ± 0.0234193.4 ± 5.6181.1 ± 21.70.80
Yu1-0780.05002 ± 0.001650.3717 ± 0.0387314.6 ± 10.4320.9 ± 33.40.42Yu2-0210.33004 ± 0.005915.1093 ± 0.18581838.6 ± 32.91837.6 ± 66.80.19
Yu1-0790.32841 ± 0.008345.0641 ± 0.20091830.7 ± 46.51830.0 ± 72.60.14Yu2-0220.01857 ± 0.000390.1307 ± 0.0085118.6 ± 2.5124.7 ± 8.10.76
Yu1-0800.02611 ± 0.000710.1719 ± 0.0106166.2 ± 4.5161.1 ± 9.90.27Yu2-0230.03348 ± 0.000960.2360 ± 0.0269212.3 ± 6.1215.1 ± 24.50.85
Yu1-0810.02959 ± 0.000830.2063 ± 0.0145188.0 ± 5.3190.5 ± 13.30.59Yu2-0240.30775 ± 0.006994.7734 ± 0.16551729.6 ± 39.31780.2 ± 61.70.15
Yu1-0820.02760 ± 0.000570.1854 ± 0.0128175.5 ± 3.6172.7 ± 11.90.58Yu2-0250.34762 ± 0.009035.5670 ± 0.29481923.2 ± 49.91910.9 ± 101.21.02
Yu1-0830.35905 ± 0.005806.9546 ± 0.19541977.7 ± 32.02105.6 ± 59.20.15Yu2-0260.39270 ± 0.009307.3412 ± 0.29092135.3 ± 50.62153.8 ± 85.30.28
Yu1-0840.04527 ± 0.000860.3571 ± 0.0191285.4 ± 5.4310.1 ± 16.60.68Yu2-0270.02803 ± 0.000720.1874 ± 0.0130178.2 ± 4.6174.4 ± 12.10.20
Yu1-0850.07313 ± 0.001590.5711 ± 0.0411455.0 ± 9.9458.7 ± 33.00.68Yu2-0280.08018 ± 0.002210.5913 ± 0.0481497.2 ± 13.7471.7 ± 38.30.76

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Grain No.206Pb/238U207Pb/235U238U–206Pb age (Ma)235U–207Pb age (Ma)Th/UGrain No.206Pb/238U207Pb/235U238U–206Pb age (Ma)235U–207Pb age (Ma)Th/U
Yu2-0290.02707 ± 0.000720.2032 ± 0.0151172.2 ± 4.6187.9 ± 14.00.40Yu2-1150.33730 ± 0.007095.2624 ± 0.19371873.7 ± 39.41862.7 ± 68.60.36
Yu2-0300.02598 ± 0.000710.1866 ± 0.0149165.3 ± 4.5173.7 ± 13.90.64Yu2-1160.03074 ± 0.000570.2235 ± 0.0100195.2 ± 3.6204.8 ± 9.20.39
Yu2-0310.03135 ± 0.000870.2396 ± 0.0193199.0 ± 5.5218.1 ± 17.60.58Yu2-1170.02859 ± 0.000560.1962 ± 0.0107181.7 ± 3.6181.9 ± 9.90.54
Yu2-0320.34609 ± 0.006305.4136 ± 0.16101915.9 ± 34.91886.9 ± 56.10.09Yu2-1180.02263 ± 0.000580.1416 ± 0.0139144.2 ± 3.7134.5 ± 13.21.25
Yu2-0330.02281 ± 0.000660.1722 ± 0.0185145.4 ± 4.2161.3 ± 17.30.80Yu2-1190.02817 ± 0.000550.1920 ± 0.0102179.1 ± 3.5178.3 ± 9.50.22
Yu2-0340.03945 ± 0.000960.2761 ± 0.0225249.4 ± 6.0247.5 ± 20.20.38Yu2-1200.44076 ± 0.007829.2948 ± 0.24902354.1 ± 41.82367.4 ± 63.40.41
Yu2-0350.02933 ± 0.000640.1961 ± 0.0127186.4 ± 4.0181.8 ± 11.80.38Yu2-1210.05568 ± 0.001640.4115 ± 0.0460349.3 ± 10.3349.9 ± 39.10.47
Yu2-0360.44876 ± 0.008399.8060 ± 0.30822389.7 ± 44.72416.6 ± 76.00.74Yu2-1220.44581 ± 0.007929.7228 ± 0.22742376.6 ± 42.22408.8 ± 56.32.01
Yu2-0370.03227 ± 0.000700.2225 ± 0.0143204.7 ± 4.4204.0 ± 13.10.50Yu2-1230.03261 ± 0.000720.2525 ± 0.0739206.9 ± 4.5228.6 ± 66.90.81
Yu2-0380.01707 ± 0.000370.1116 ± 0.0074109.1 ± 2.4107.4 ± 7.10.79Yu2-1240.39375 ± 0.007456.9113 ± 0.22522140.2 ± 40.52100.0 ± 68.40.17
Yu2-0390.30182 ± 0.005784.7164 ± 0.17421700.3 ± 32.51770.1 ± 65.40.16Yu2-1250.34194 ± 0.008565.2821 ± 0.19631896.0 ± 47.51865.9 ± 69.30.93
Yu2-0400.31219 ± 0.006324.8866 ± 0.20771751.5 ± 35.41799.9 ± 76.50.61Yu2-1260.02890 ± 0.000750.2057 ± 0.0108183.6 ± 4.8190.0 ± 10.00.34
Yu2-0410.34474 ± 0.008595.6217 ± 0.35041909.4 ± 47.61919.4 ± 119.61.37Yu2-1270.03037 ± 0.000800.2107 ± 0.0122192.9 ± 5.1194.1 ± 11.20.60
Yu2-0420.27325 ± 0.005434.2696 ± 0.17441557.3 ± 31.01687.5 ± 68.90.66Yu2-1280.01636 ± 0.000460.1065 ± 0.0082104.6 ± 2.9102.7 ± 7.90.72
Yu2-0430.39994 ± 0.008008.0902 ± 0.32502168.8 ± 43.42241.1 ± 90.01.31Yu2-1290.03593 ± 0.001020.2394 ± 0.0186227.5 ± 6.5217.9 ± 16.90.69
Yu2-0440.02641 ± 0.000720.1787 ± 0.0187168.0 ± 4.6166.9 ± 17.50.54Yu2-1300.03702 ± 0.000730.2573 ± 0.0155234.3 ± 4.6232.5 ± 14.00.45
Yu2-0450.03908 ± 0.000930.2979 ± 0.0233247.1 ± 5.9264.8 ± 20.70.24Yu2-1310.02595 ± 0.000580.1789 ± 0.0145165.2 ± 3.7167.1 ± 13.60.35
Yu2-0460.02794 ± 0.000560.1864 ± 0.0105177.6 ± 3.6173.6 ± 9.80.20Yu2-1320.02711 ± 0.000580.1890 ± 0.0138172.4 ± 3.7175.8 ± 12.90.61
Yu2-0470.02973 ± 0.000570.2126 ± 0.0099188.8 ± 3.6195.7 ± 9.10.31Yu2-1330.01659 ± 0.000430.1211 ± 0.0122106.1 ± 2.7116.0 ± 11.70.39
Yu2-0480.30971 ± 0.005464.7676 ± 0.13201739.3 ± 30.61779.1 ± 49.30.42Yu2-1340.03081 ± 0.000940.2306 ± 0.0308195.6 ± 6.0210.7 ± 28.10.49
Yu2-0490.30912 ± 0.005464.8220 ± 0.13451736.4 ± 30.71788.7 ± 49.90.17Yu2-1350.01711 ± 0.000450.1138 ± 0.0093109.4 ± 2.9109.4 ± 9.00.41
Yu2-0500.03933 ± 0.001450.2908 ± 0.0169248.7 ± 9.2259.2 ± 15.10.74Yu2-1360.01566 ± 0.000440.1106 ± 0.0100100.1 ± 2.8106.5 ± 9.70.37
Yu2-0510.30009 ± 0.010894.6834 ± 0.22191691.8 ± 61.41764.2 ± 83.60.12Yu2-1370.02376 ± 0.000610.1585 ± 0.0124151.4 ± 3.9149.4 ± 11.70.36
Yu2-0520.02328 ± 0.000900.1589 ± 0.0129148.3 ± 5.8149.7 ± 12.21.52Yu2-1380.02929 ± 0.000700.2223 ± 0.0132186.1 ± 4.4203.8 ± 12.10.19
Yu2-0530.34617 ± 0.012575.4714 ± 0.26051916.3 ± 69.61896.1 ± 90.30.65Yu2-1390.03119 ± 0.000740.2229 ± 0.0132198.0 ± 4.7204.4 ± 12.10.40
Yu2-0540.32788 ± 0.011875.2129 ± 0.24391828.1 ± 66.21854.7 ± 86.80.11Yu2-1400.03850 ± 0.001150.2541 ± 0.0272243.5 ± 7.3229.9 ± 24.60.10
Yu2-0550.03070 ± 0.001230.2291 ± 0.0208194.9 ± 7.8209.5 ± 19.00.57Site 3 (Sample 160705-06) in Chikai Unit (M1) of Miyama Complex
Yu2-0560.03823 ± 0.001130.2984 ± 0.0335241.9 ± 7.1265.2 ± 29.81.19M1-0010.01528 ± 0.000680.1127 ± 0.016397.8 ± 4.4108.4 ± 15.70.50
Yu2-0570.35667 ± 0.006885.7215 ± 0.27711966.4 ± 37.91934.5 ± 93.70.39M1-0020.01605 ± 0.000680.1162 ± 0.0153102.7 ± 4.4111.6 ± 14.70.45
Yu2-0580.02911 ± 0.000600.1904 ± 0.0121185.0 ± 3.8176.9 ± 11.20.33M1-0030.01457 ± 0.000620.1042 ± 0.013893.2 ± 4.0100.7 ± 13.30.96
Yu2-0590.39177 ± 0.007426.7510 ± 0.31662131.0 ± 40.32079.3 ± 97.50.25M1-0040.01337 ± 0.000540.0970 ± 0.010885.6 ± 3.494.0 ± 10.50.50
Yu2-0600.38692 ± 0.007276.7445 ± 0.31252108.5 ± 39.62078.4 ± 96.30.20M1-0050.01512 ± 0.000640.1065 ± 0.013696.7 ± 4.1102.7 ± 13.10.40
Yu2-0610.04515 ± 0.001200.3293 ± 0.0324284.7 ± 7.6289.0 ± 28.40.65M1-0060.01854 ± 0.000690.1256 ± 0.0096118.4 ± 4.4120.1 ± 9.20.25
Yu2-0620.03751 ± 0.000950.2706 ± 0.0248237.4 ± 6.0243.2 ± 22.30.68M1-0070.01505 ± 0.000670.1097 ± 0.014696.3 ± 4.3105.7 ± 14.10.44
Yu2-0630.35662 ± 0.011485.6792 ± 0.26011966.1 ± 63.31928.1 ± 88.30.36M1-0080.01472 ± 0.000660.1057 ± 0.014794.2 ± 4.2102.0 ± 14.20.61
Yu2-0640.01673 ± 0.000670.1218 ± 0.0147107.0 ± 4.3116.7 ± 14.10.25M1-0090.01400 ± 0.000630.0870 ± 0.013089.6 ± 4.084.7 ± 12.60.58
Yu2-0650.02961 ± 0.000530.2053 ± 0.0115188.1 ± 3.4189.6 ± 10.60.21M1-0100.01486 ± 0.000600.0996 ± 0.014195.1 ± 3.996.4 ± 13.70.42
Yu2-0660.03410 ± 0.000640.2298 ± 0.0144216.1 ± 4.1210.0 ± 13.10.41M1-0110.01554 ± 0.000600.0992 ± 0.013099.4 ± 3.896.1 ± 12.50.49
Yu2-0670.35519 ± 0.005835.5668 ± 0.20501959.3 ± 32.11910.9 ± 70.40.36M1-0120.01573 ± 0.000610.1008 ± 0.0132100.6 ± 3.997.5 ± 12.70.83
Yu2-0680.31045 ± 0.005015.4161 ± 0.19271742.9 ± 28.11887.3 ± 67.20.14M1-0130.01406 ± 0.000600.0875 ± 0.014190.0 ± 3.985.1 ± 13.70.55
Yu2-0690.30484 ± 0.005844.9608 ± 0.13951715.3 ± 32.91812.6 ± 51.00.39M1-0140.01668 ± 0.000500.1135 ± 0.0107106.6 ± 3.2109.1 ± 10.30.34
Yu2-0700.03304 ± 0.000770.2387 ± 0.0167209.5 ± 4.9217.3 ± 15.20.75M1-0150.04354 ± 0.001300.3058 ± 0.0291274.7 ± 8.2270.9 ± 25.70.91
Yu2-0710.28792 ± 0.005624.3254 ± 0.13441631.1 ± 31.91698.2 ± 52.80.93M1-0160.05879 ± 0.001820.4456 ± 0.0441368.3 ± 11.4374.2 ± 37.00.72
Yu2-0720.02802 ± 0.000650.1938 ± 0.0137178.1 ± 4.1179.8 ± 12.80.32M1-0170.01503 ± 0.000420.1015 ± 0.008496.1 ± 2.798.1 ± 8.10.29
Yu2-0730.02954 ± 0.000600.2093 ± 0.0099187.6 ± 3.8192.9 ± 9.10.40M1-0180.01674 ± 0.000830.1120 ± 0.0199107.0 ± 5.3107.8 ± 19.20.47
Yu2-0740.04916 ± 0.001270.3650 ± 0.0296309.4 ± 8.0315.9 ± 25.70.68M1-0190.01680 ± 0.000750.1124 ± 0.0163107.4 ± 4.8108.2 ± 15.70.56
Yu2-0750.38176 ± 0.008126.0917 ± 0.23392084.5 ± 44.31989.0 ± 76.40.34M1-0200.01422 ± 0.000580.0914 ± 0.010791.0 ± 3.788.8 ± 10.40.70
Yu2-0760.33106 ± 0.006885.0870 ± 0.18291843.5 ± 38.31833.9 ± 65.90.30M1-0210.01605 ± 0.000790.0990 ± 0.0176102.6 ± 5.095.9 ± 17.10.53
Yu2-0770.02569 ± 0.000600.1703 ± 0.0114163.5 ± 3.8159.7 ± 10.70.53M1-0220.01376 ± 0.000620.0937 ± 0.013388.1 ± 3.991.0 ± 12.90.55
Yu2-0780.03186 ± 0.001080.2241 ± 0.0303202.2 ± 6.9205.3 ± 27.70.70M1-0230.01612 ± 0.000680.1043 ± 0.0131103.1 ± 4.3100.8 ± 12.70.32
Yu2-0790.35789 ± 0.007405.6833 ± 0.19971972.2 ± 40.81928.8 ± 67.80.36M1-0240.01588 ± 0.000740.0984 ± 0.0185101.6 ± 4.795.3 ± 18.00.47
Yu2-0800.02532 ± 0.000540.1745 ± 0.0083161.2 ± 3.4163.3 ± 7.80.70M1-0250.35579 ± 0.010265.7542 ± 0.25611962.2 ± 56.61939.5 ± 86.30.31
Yu2-0810.03225 ± 0.001000.2416 ± 0.0245204.6 ± 6.3219.7 ± 22.30.75M1-0260.04741 ± 0.002380.3672 ± 0.0699298.6 ± 15.0317.6 ± 60.40.32
Yu2-0820.02796 ± 0.000690.1935 ± 0.0115177.7 ± 4.4179.6 ± 10.70.24M1-0270.01367 ± 0.000510.0952 ± 0.011687.5 ± 3.392.3 ± 11.20.78
Yu2-0830.02793 ± 0.000690.1866 ± 0.0113177.6 ± 4.4173.7 ± 10.50.55M1-0280.01493 ± 0.000740.0903 ± 0.018995.5 ± 4.787.8 ± 18.40.88
Yu2-0840.02743 ± 0.000710.1972 ± 0.0134174.4 ± 4.5182.8 ± 12.50.47M1-0290.01507 ± 0.000640.1000 ± 0.015796.4 ± 4.196.7 ± 15.20.70
Yu2-0850.03023 ± 0.001030.1985 ± 0.0595192.0 ± 6.5183.9 ± 55.10.85M1-0300.01461 ± 0.000600.1018 ± 0.014893.5 ± 3.898.5 ± 14.30.73
Yu2-0860.04627 ± 0.001440.3125 ± 0.0712291.6 ± 9.1276.1 ± 62.90.71M1-0310.01648 ± 0.000810.1134 ± 0.0171105.4 ± 5.2109.0 ± 16.50.51
Yu2-0870.35058 ± 0.007055.9553 ± 0.15681937.3 ± 38.91969.3 ± 51.90.19M1-0320.01451 ± 0.000710.1010 ± 0.015092.9 ± 4.697.7 ± 14.50.58
Yu2-0880.32438 ± 0.006695.0844 ± 0.15731811.1 ± 37.31833.4 ± 56.70.38M1-0330.01597 ± 0.000860.1084 ± 0.0198102.1 ± 5.5104.5 ± 19.10.38
Yu2-0890.31279 ± 0.006444.8634 ± 0.14921754.4 ± 36.11795.9 ± 55.10.28M1-0340.01503 ± 0.000650.0998 ± 0.010396.1 ± 4.196.6 ± 10.00.42
Yu2-0900.37777 ± 0.007527.0900 ± 0.17342065.9 ± 41.12122.7 ± 51.90.41M1-0350.01432 ± 0.000710.0956 ± 0.015391.6 ± 4.692.7 ± 14.91.02
Yu2-0910.03764 ± 0.000950.2643 ± 0.0298238.2 ± 6.0238.1 ± 26.90.64M1-0360.01681 ± 0.000730.1188 ± 0.0123107.5 ± 4.6114.0 ± 11.80.39
Yu2-0920.02742 ± 0.000500.1945 ± 0.0115174.4 ± 3.2180.5 ± 10.70.41M1-0370.01671 ± 0.000790.1084 ± 0.0151106.9 ± 5.0104.5 ± 14.60.64
Yu2-0930.28256 ± 0.004804.4734 ± 0.14851604.3 ± 27.31726.0 ± 57.30.32M1-0380.01441 ± 0.000520.1021 ± 0.013092.2 ± 3.398.7 ± 12.60.83
Yu2-0940.03651 ± 0.000790.2808 ± 0.0269231.2 ± 5.0251.3 ± 24.10.77M1-0390.01794 ± 0.000680.1090 ± 0.0158114.6 ± 4.3105.0 ± 15.20.34
Yu2-0950.47224 ± 0.0075011.3142 ± 0.29122493.4 ± 39.62549.3 ± 65.60.55M1-0400.01518 ± 0.000640.1022 ± 0.016797.1 ± 4.198.8 ± 16.20.57
Yu2-0960.03953 ± 0.000810.2800 ± 0.0246249.9 ± 5.1250.7 ± 22.00.82M1-0410.01594 ± 0.000740.1161 ± 0.0212101.9 ± 4.7111.5 ± 20.40.69
Yu2-0970.02792 ± 0.000740.1864 ± 0.0133177.5 ± 4.7173.6 ± 12.40.38M1-0420.01482 ± 0.000580.1037 ± 0.014594.8 ± 3.7100.1 ± 14.00.47
Yu2-0980.04652 ± 0.001240.3448 ± 0.0240293.1 ± 7.8300.8 ± 20.90.33M1-0430.01729 ± 0.000370.1155 ± 0.0088110.5 ± 2.4111.0 ± 8.40.28
Yu2-0990.03378 ± 0.000910.2571 ± 0.0181214.2 ± 5.8232.3 ± 16.40.67M1-0440.01640 ± 0.000480.1156 ± 0.0138104.9 ± 3.1111.1 ± 13.30.75
Yu2-1000.33284 ± 0.007785.1492 ± 0.18561852.1 ± 43.31844.2 ± 66.50.40M1-0450.02058 ± 0.000510.1400 ± 0.0133131.3 ± 3.2133.1 ± 12.60.24
Yu2-1010.26696 ± 0.006274.1236 ± 0.15201525.3 ± 35.91658.9 ± 61.20.35M1-0460.01339 ± 0.000310.0928 ± 0.007985.8 ± 2.090.1 ± 7.70.52
Yu2-1020.35245 ± 0.008475.4469 ± 0.21911946.3 ± 46.81892.2 ± 76.10.31M1-0470.04340 ± 0.001330.2916 ± 0.0267273.9 ± 8.4259.8 ± 23.80.44
Yu2-1030.02911 ± 0.000580.2069 ± 0.0143185.0 ± 3.7191.0 ± 13.20.17M1-0480.01450 ± 0.000570.0956 ± 0.014592.8 ± 3.792.7 ± 14.10.68
Yu2-1040.04057 ± 0.000900.2868 ± 0.0237256.4 ± 5.7256.0 ± 21.20.74M1-0490.01918 ± 0.000710.1406 ± 0.0184122.5 ± 4.6133.6 ± 17.50.39
Yu2-1050.02726 ± 0.000480.1807 ± 0.0102173.4 ± 3.1168.7 ± 9.50.49M1-0500.01590 ± 0.000630.1132 ± 0.0167101.7 ± 4.0108.9 ± 16.10.53
Yu2-1060.04062 ± 0.001130.2842 ± 0.0327256.7 ± 7.2253.9 ± 29.20.32M1-0510.01541 ± 0.000500.1096 ± 0.011298.6 ± 3.2105.6 ± 10.80.74
Yu2-1070.39297 ± 0.005598.6158 ± 0.20252136.6 ± 30.42298.1 ± 54.00.16M1-0520.01589 ± 0.000470.1152 ± 0.0094101.6 ± 3.0110.7 ± 9.10.39
Yu2-1080.03068 ± 0.000630.2249 ± 0.0162194.8 ± 4.0206.0 ± 14.80.28M1-0530.01580 ± 0.000560.1078 ± 0.0156101.1 ± 3.6103.9 ± 15.00.49
Yu2-1090.03265 ± 0.000870.2174 ± 0.0239207.1 ± 5.5199.7 ± 22.00.20M1-0540.03423 ± 0.001010.2325 ± 0.0256217.0 ± 6.4212.2 ± 23.30.40
Yu2-1100.32934 ± 0.006635.1880 ± 0.16231835.2 ± 36.91850.6 ± 57.90.12M1-0550.01704 ± 0.000570.1243 ± 0.0161108.9 ± 3.7119.0 ± 15.40.28
Yu2-1110.37595 ± 0.007775.8510 ± 0.20302057.3 ± 42.51953.9 ± 67.80.37M1-0560.01728 ± 0.000760.1130 ± 0.0216110.4 ± 4.8108.7 ± 20.80.48
Yu2-1120.02800 ± 0.000630.1950 ± 0.0111178.0 ± 4.0180.9 ± 10.30.40M1-0570.01556 ± 0.000830.1014 ± 0.024499.5 ± 5.398.0 ± 23.60.59
Yu2-1130.04555 ± 0.001340.3024 ± 0.0326287.1 ± 8.4268.2 ± 28.90.69M1-0580.01577 ± 0.000430.0992 ± 0.0110100.9 ± 2.796.0 ± 10.70.29
Yu2-1140.03858 ± 0.000970.2926 ± 0.0219244.0 ± 6.1260.6 ± 19.50.12M1-0590.01564 ± 0.000510.0991 ± 0.0139100.0 ± 3.295.9 ± 13.50.70

Grain No.206Pb/238U207Pb/235U238U–206Pb age (Ma)235U–207Pb age (Ma)Th/UGrain No.206Pb/238U207Pb/235U238U–206Pb age (Ma)235U–207Pb age (Ma)Th/U
M1-0600.01614 ± 0.000620.1054 ± 0.0181103.2 ± 4.0101.7 ± 17.40.74M2-0590.01816 ± 0.000780.1139 ± 0.0158116.0 ± 5.0109.5 ± 15.20.56
M1-0610.01477 ± 0.000510.0957 ± 0.014494.5 ± 3.392.8 ± 13.90.84M2-0600.01481 ± 0.000620.1093 ± 0.013394.8 ± 3.9105.3 ± 12.80.36
M1-0620.01528 ± 0.000530.1009 ± 0.014297.8 ± 3.497.6 ± 13.70.70M2-0610.04857 ± 0.002210.3552 ± 0.0521305.7 ± 13.9308.6 ± 45.30.31
M1-0630.01783 ± 0.000610.1186 ± 0.0162113.9 ± 3.9113.8 ± 15.50.32M2-0620.01883 ± 0.000660.1221 ± 0.0161120.3 ± 4.2116.9 ± 15.40.41
M1-0640.01550 ± 0.000650.1107 ± 0.019499.1 ± 4.2106.6 ± 18.70.50M2-0630.01665 ± 0.000490.1124 ± 0.0105106.5 ± 3.1108.1 ± 10.10.38
M1-0650.01562 ± 0.000510.1152 ± 0.014399.9 ± 3.3110.7 ± 13.80.41M2-0640.01611 ± 0.000640.0987 ± 0.0163103.0 ± 4.195.6 ± 15.80.52
M1-0660.01399 ± 0.000350.0970 ± 0.007689.6 ± 2.294.0 ± 7.40.46M2-0650.03960 ± 0.001470.2868 ± 0.0392250.3 ± 9.3256.0 ± 35.00.72
M1-0670.01580 ± 0.000420.1120 ± 0.0103101.1 ± 2.7107.8 ± 9.90.28M2-0660.01632 ± 0.000540.1093 ± 0.0129104.4 ± 3.5105.3 ± 12.50.53
M1-0680.01511 ± 0.000380.0971 ± 0.008096.7 ± 2.494.1 ± 7.80.88M2-0670.01412 ± 0.000590.0873 ± 0.011090.4 ± 3.885.0 ± 10.70.55
M1-0690.01458 ± 0.000510.1032 ± 0.013693.3 ± 3.399.7 ± 13.20.47M2-0680.01603 ± 0.000670.1142 ± 0.0141102.5 ± 4.3109.8 ± 13.50.27
M1-0700.01556 ± 0.000620.0950 ± 0.016399.6 ± 4.092.2 ± 15.80.46M2-0690.01575 ± 0.000700.1070 ± 0.0124100.7 ± 4.5103.2 ± 12.00.63
M1-0710.01631 ± 0.000640.1193 ± 0.0185104.3 ± 4.1114.5 ± 17.80.48M2-0700.04096 ± 0.002110.2765 ± 0.0472258.8 ± 13.3247.8 ± 42.30.73
M1-0720.01700 ± 0.000700.1138 ± 0.0196108.7 ± 4.5109.4 ± 18.80.67M2-0710.01293 ± 0.000560.0850 ± 0.009482.8 ± 3.682.8 ± 9.10.49
M1-0730.01532 ± 0.000490.1060 ± 0.012498.0 ± 3.2102.3 ± 11.90.39M2-0720.01539 ± 0.000790.1034 ± 0.017998.5 ± 5.199.9 ± 17.30.38
M1-0740.01751 ± 0.000510.1202 ± 0.0119111.9 ± 3.3115.3 ± 11.40.23M2-0730.01686 ± 0.000750.1158 ± 0.0134107.8 ± 4.8111.3 ± 12.90.60
M1-0750.04256 ± 0.001870.3201 ± 0.0614268.7 ± 11.8282.0 ± 54.10.50M2-0740.01598 ± 0.000840.1102 ± 0.0196102.2 ± 5.4106.1 ± 18.90.46
M1-0760.01655 ± 0.000440.1190 ± 0.0136105.8 ± 2.8114.2 ± 13.00.75M2-0750.01455 ± 0.000510.1057 ± 0.013893.1 ± 3.2102.0 ± 13.30.65
M1-0770.01563 ± 0.000470.1055 ± 0.0142100.0 ± 3.0101.8 ± 13.70.66M2-0760.01504 ± 0.000650.1070 ± 0.019196.2 ± 4.2103.2 ± 18.40.79
M1-0780.01784 ± 0.000520.1138 ± 0.0152114.0 ± 3.3109.4 ± 14.70.47M2-0770.01365 ± 0.000520.0873 ± 0.013687.4 ± 3.384.9 ± 13.31.00
M1-0790.01652 ± 0.000410.1187 ± 0.0124105.6 ± 2.6113.9 ± 11.90.35M2-0780.01698 ± 0.000600.1112 ± 0.0154108.5 ± 3.8107.1 ± 14.80.33
M1-0800.01382 ± 0.000430.1011 ± 0.013588.5 ± 2.797.8 ± 13.10.56Site 5 (Sample 160705-01) in Hattomaki Unit (M3) of Miyama Complex
M1-0810.01453 ± 0.000450.0897 ± 0.009393.0 ± 2.987.2 ± 9.00.39M3-0010.05850 ± 0.007290.4754 ± 0.1341366.5 ± 45.7394.9 ± 111.40.92
M1-0820.01468 ± 0.000610.0966 ± 0.016093.9 ± 3.993.7 ± 15.50.76M3-0020.24019 ± 0.009983.5519 ± 0.22261387.7 ± 57.61538.8 ± 96.40.47
M1-0830.01424 ± 0.000460.0996 ± 0.010791.2 ± 3.096.4 ± 10.30.74M3-0030.33403 ± 0.013415.8980 ± 0.31951857.9 ± 74.61960.9 ± 106.20.35
M1-0840.03231 ± 0.000890.2323 ± 0.0161205.0 ± 5.6212.1 ± 14.70.54M3-0040.43957 ± 0.017879.5363 ± 0.52762348.7 ± 95.52391.0 ± 132.30.89
M1-0850.01482 ± 0.000550.0912 ± 0.013094.9 ± 3.588.6 ± 12.70.57M3-0050.48244 ± 0.0193711.2839 ± 0.49462537.9 ± 101.92546.8 ± 111.60.45
M1-0860.01370 ± 0.000390.0953 ± 0.007387.7 ± 2.592.5 ± 7.10.61M3-0060.03281 ± 0.001840.2115 ± 0.0305208.1 ± 11.7194.8 ± 28.10.84
Site 4 (Sample 160705-02) in Gomadanzan Unit (M2) of Miyama ComplexM3-0070.30011 ± 0.007064.6679 ± 0.16021691.9 ± 39.81761.4 ± 60.50.22
M2-0010.01512 ± 0.000550.0922 ± 0.014296.7 ± 3.589.6 ± 13.80.56M3-0080.02922 ± 0.000820.1880 ± 0.0159185.7 ± 5.2174.9 ± 14.80.39
M2-0020.04319 ± 0.001960.2801 ± 0.0544272.6 ± 12.4250.8 ± 48.70.42M3-0090.41899 ± 0.010698.5583 ± 0.35392255.9 ± 57.52292.1 ± 94.80.24
M2-0030.01287 ± 0.000330.0869 ± 0.006882.4 ± 2.184.6 ± 6.70.39M3-0100.44011 ± 0.010468.1774 ± 0.28022351.1 ± 55.92250.8 ± 77.10.26
M2-0040.04466 ± 0.001730.2934 ± 0.0436281.6 ± 10.9261.3 ± 38.80.51M3-0110.33916 ± 0.008885.1873 ± 0.24931882.6 ± 49.31850.5 ± 88.90.81
M2-0050.01645 ± 0.000610.1174 ± 0.0161105.2 ± 3.9112.7 ± 15.40.35M3-0120.56269 ± 0.0204013.7939 ± 1.13892877.7 ± 104.32735.6 ± 225.90.58
M2-0060.01394 ± 0.000650.0932 ± 0.018189.3 ± 4.290.5 ± 17.50.59M3-0130.43205 ± 0.015889.3971 ± 0.79602314.9 ± 85.12377.5 ± 201.40.67
M2-0070.01506 ± 0.000860.0910 ± 0.016896.3 ± 5.588.4 ± 16.30.51M3-0140.34000 ± 0.012315.5575 ± 0.46711886.7 ± 68.31909.5 ± 160.50.30
M2-0080.01654 ± 0.000820.1066 ± 0.0238105.7 ± 5.2102.9 ± 23.00.79M3-0150.34359 ± 0.012455.4157 ± 0.45631903.9 ± 69.01887.3 ± 159.00.14
M2-0090.01523 ± 0.000390.0963 ± 0.008097.4 ± 2.593.4 ± 7.80.33M3-0160.32813 ± 0.011855.6375 ± 0.47061829.3 ± 66.11921.8 ± 160.40.51
M2-0100.01836 ± 0.000470.1168 ± 0.0097117.3 ± 3.0112.2 ± 9.30.29M3-0170.01212 ± 0.000590.0839 ± 0.014777.6 ± 3.881.8 ± 14.30.42
M2-0110.01342 ± 0.000360.0858 ± 0.007885.9 ± 2.383.6 ± 7.60.32M3-0180.45878 ± 0.0170410.9825 ± 0.93862434.2 ± 90.42521.6 ± 215.50.56
M2-0120.01419 ± 0.000470.0948 ± 0.012390.8 ± 3.092.0 ± 12.00.53M3-0190.34373 ± 0.012666.1176 ± 0.52691904.6 ± 70.21992.7 ± 171.60.15
M2-0130.01515 ± 0.000430.1041 ± 0.010397.0 ± 2.7100.6 ± 10.00.31M3-0200.44305 ± 0.015888.8143 ± 0.72122364.3 ± 84.72318.9 ± 189.70.40
M2-0140.01669 ± 0.000530.1140 ± 0.0135106.7 ± 3.4109.6 ± 13.00.60M3-0210.38735 ± 0.008617.1727 ± 0.25222110.5 ± 46.92133.0 ± 75.00.14
M2-0150.01443 ± 0.000660.0874 ± 0.017492.3 ± 4.285.1 ± 16.90.47M3-0220.02723 ± 0.000830.2026 ± 0.0212173.2 ± 5.3187.4 ± 19.60.53
M2-0160.01537 ± 0.000460.1075 ± 0.009798.3 ± 2.9103.7 ± 9.30.35M3-0230.44212 ± 0.0110610.0244 ± 0.46562360.1 ± 59.02436.9 ± 113.20.45
M2-0170.01666 ± 0.000500.1137 ± 0.0104106.5 ± 3.2109.3 ± 10.00.29M3-0240.31680 ± 0.006915.0013 ± 0.16661774.1 ± 38.71819.5 ± 60.60.20
M2-0180.01608 ± 0.000550.1074 ± 0.0132102.9 ± 3.5103.6 ± 12.70.30M3-0250.32397 ± 0.007085.6488 ± 0.18721809.1 ± 39.51923.5 ± 63.80.12
M2-0190.01440 ± 0.000450.1040 ± 0.008992.2 ± 2.9100.4 ± 8.60.32M3-0260.33157 ± 0.007215.6222 ± 0.18351846.0 ± 40.11919.4 ± 62.60.30
M2-0200.01676 ± 0.000710.1231 ± 0.0179107.1 ± 4.5117.9 ± 17.20.57M3-0270.31506 ± 0.009975.0267 ± 0.24491765.6 ± 55.91823.8 ± 88.90.38
M2-0210.01749 ± 0.000690.1130 ± 0.0146111.8 ± 4.4108.7 ± 14.00.38M3-0280.35280 ± 0.011405.6616 ± 0.29911948.0 ± 63.01925.5 ± 101.70.31
M2-0220.01507 ± 0.000570.1074 ± 0.011796.4 ± 3.6103.6 ± 11.30.33M3-0290.30026 ± 0.009664.7000 ± 0.24521692.6 ± 54.51767.2 ± 92.20.60
M2-0230.01289 ± 0.000430.0881 ± 0.006282.6 ± 2.885.7 ± 6.00.28M3-0300.39751 ± 0.012788.6305 ± 0.43362157.6 ± 69.42299.7 ± 115.50.51
M2-0240.01580 ± 0.000570.1023 ± 0.0100101.0 ± 3.698.9 ± 9.70.36M3-0310.29785 ± 0.009684.8453 ± 0.26091680.6 ± 54.61792.7 ± 96.50.31
M2-0250.01943 ± 0.000520.1320 ± 0.0148124.0 ± 3.3125.9 ± 14.10.45M3-0320.31148 ± 0.009914.8101 ± 0.24011748.0 ± 55.61786.6 ± 89.20.24
M2-0260.45382 ± 0.008459.6216 ± 0.56032412.2 ± 44.92399.2 ± 139.70.28M3-0330.27492 ± 0.008644.4461 ± 0.20921565.7 ± 49.21720.9 ± 81.00.10
M2-0270.01682 ± 0.000430.1182 ± 0.0124107.5 ± 2.8113.4 ± 11.90.37M3-0340.31298 ± 0.004154.8704 ± 0.15681755.3 ± 23.31797.1 ± 57.90.18
M2-0280.01303 ± 0.000420.0847 ± 0.011983.4 ± 2.782.5 ± 11.60.44M3-0350.29957 ± 0.004244.8954 ± 0.17221689.2 ± 23.91801.4 ± 63.30.13
M2-0290.01429 ± 0.000500.0912 ± 0.014491.5 ± 3.288.6 ± 14.00.92M3-0360.31724 ± 0.005434.9510 ± 0.22281776.2 ± 30.41810.9 ± 81.50.35
M2-0300.01565 ± 0.000500.1055 ± 0.0145100.1 ± 3.2101.8 ± 14.00.47M3-0370.32048 ± 0.004625.0713 ± 0.18271792.1 ± 25.81831.2 ± 66.00.13
M2-0310.01623 ± 0.000490.1079 ± 0.0140103.8 ± 3.1104.1 ± 13.50.51M3-0380.30604 ± 0.004954.8184 ± 0.20181721.2 ± 27.81788.1 ± 74.90.12
M2-0320.01468 ± 0.000720.0885 ± 0.016093.9 ± 4.686.1 ± 15.60.56M3-0390.34634 ± 0.005565.7967 ± 0.18211917.1 ± 30.81945.8 ± 61.10.41
M2-0330.01541 ± 0.000660.1054 ± 0.013798.6 ± 4.2101.7 ± 13.20.74M3-0400.03477 ± 0.000680.2394 ± 0.0172220.3 ± 4.3217.9 ± 15.70.58
M2-0340.01249 ± 0.000670.0753 ± 0.015880.0 ± 4.373.7 ± 15.51.50M3-0410.42758 ± 0.007958.7703 ± 0.37582294.8 ± 42.72314.3 ± 99.20.64
M2-0350.01171 ± 0.000460.0850 ± 0.008575.0 ± 2.982.8 ± 8.31.17M3-0420.04292 ± 0.000840.3018 ± 0.0175270.9 ± 5.3267.8 ± 15.50.31
M2-0360.01409 ± 0.000500.0924 ± 0.013090.2 ± 3.289.7 ± 12.60.77M3-0430.01543 ± 0.000560.1129 ± 0.017298.7 ± 3.6108.6 ± 16.50.32
M2-0370.01651 ± 0.000450.1223 ± 0.0104105.6 ± 2.8117.2 ± 10.00.39M3-0440.45494 ± 0.008269.8946 ± 0.41032417.2 ± 43.92424.9 ± 100.61.32
M2-0380.01730 ± 0.000760.1203 ± 0.0222110.6 ± 4.9115.4 ± 21.30.48M3-0450.29874 ± 0.005264.8806 ± 0.19881685.1 ± 29.71798.9 ± 73.30.15
M2-0390.01692 ± 0.000570.1053 ± 0.0142108.1 ± 3.6101.6 ± 13.70.40M3-0460.02860 ± 0.001370.2062 ± 0.0225181.8 ± 8.7190.3 ± 20.80.48
M2-0400.04208 ± 0.001240.3021 ± 0.0308265.7 ± 7.8268.0 ± 27.40.44M3-0470.38733 ± 0.017587.8829 ± 0.57142110.5 ± 95.82217.7 ± 160.70.71
M2-0410.01446 ± 0.000660.0903 ± 0.018292.6 ± 4.287.8 ± 17.70.55M3-0480.36623 ± 0.016407.1120 ± 0.49512011.6 ± 90.12125.5 ± 148.00.34
M2-0420.01532 ± 0.000460.1080 ± 0.011598.0 ± 2.9104.2 ± 11.10.27M3-0490.31207 ± 0.013824.8847 ± 0.33071750.9 ± 77.61799.6 ± 121.80.32
M2-0430.01441 ± 0.000790.0959 ± 0.022292.2 ± 5.093.0 ± 21.50.52M3-0500.32301 ± 0.009815.1919 ± 0.23931804.4 ± 54.81851.2 ± 85.30.12
M2-0440.01567 ± 0.000640.1094 ± 0.0167100.3 ± 4.1105.4 ± 16.10.39M3-0510.30477 ± 0.009904.6026 ± 0.27441714.9 ± 55.71749.7 ± 104.30.31
M2-0450.01434 ± 0.000520.0871 ± 0.011391.8 ± 3.384.8 ± 11.00.47M3-0520.03053 ± 0.001250.2168 ± 0.0303193.9 ± 7.9199.2 ± 27.80.59
M2-0460.01546 ± 0.000470.1050 ± 0.008998.9 ± 3.0101.4 ± 8.60.31M3-0530.01582 ± 0.000660.1058 ± 0.0156101.2 ± 4.2102.1 ± 15.10.37
M2-0470.01498 ± 0.000540.0960 ± 0.012295.9 ± 3.493.0 ± 11.80.50M3-0540.29973 ± 0.008944.6933 ± 0.19901690.0 ± 50.41766.0 ± 74.90.13
M2-0480.01279 ± 0.000450.0914 ± 0.009981.9 ± 2.988.8 ± 9.72.02M3-0550.29581 ± 0.009544.6026 ± 0.26651670.5 ± 53.91749.7 ± 101.30.76
M2-0490.01367 ± 0.000500.0976 ± 0.012787.5 ± 3.294.6 ± 12.30.59M3-0560.40681 ± 0.011247.5780 ± 0.30692200.3 ± 60.82182.2 ± 88.40.50
M2-0500.01415 ± 0.000440.1004 ± 0.009290.6 ± 2.897.2 ± 8.90.60M3-0570.37011 ± 0.009917.6708 ± 0.26552029.9 ± 54.32193.1 ± 75.90.36
M2-0510.03984 ± 0.001210.2941 ± 0.0255251.9 ± 7.7261.8 ± 22.70.53M3-0580.40937 ± 0.011478.6387 ± 0.35992212.0 ± 62.02300.6 ± 95.80.36
M2-0520.01488 ± 0.000630.0896 ± 0.015995.2 ± 4.187.1 ± 15.50.43M3-0590.02851 ± 0.000910.2096 ± 0.0189181.2 ± 5.8193.2 ± 17.40.23
M2-0530.39156 ± 0.010327.4980 ± 0.33982130.1 ± 56.22172.7 ± 98.50.29M3-0600.30442 ± 0.008274.9979 ± 0.19311713.2 ± 46.51818.9 ± 70.30.10
M2-0540.01326 ± 0.000770.0896 ± 0.025084.9 ± 4.987.1 ± 24.40.31M3-0610.02895 ± 0.001550.2070 ± 0.0452183.9 ± 9.8191.0 ± 41.71.07
M2-0550.01356 ± 0.000570.0867 ± 0.007586.8 ± 3.784.4 ± 7.30.55M3-0620.32053 ± 0.009154.9799 ± 0.23921792.3 ± 51.21815.8 ± 87.20.47
M2-0560.01234 ± 0.000650.0844 ± 0.014679.0 ± 4.282.2 ± 14.31.18M3-0630.02883 ± 0.000870.2162 ± 0.0165183.2 ± 5.5198.8 ± 15.20.36
M2-0570.01554 ± 0.000580.1080 ± 0.009999.4 ± 3.7104.1 ± 9.50.27M3-0640.43490 ± 0.011889.1731 ± 0.52702327.8 ± 63.62355.3 ± 135.30.95
M2-0580.01422 ± 0.000530.0996 ± 0.008991.1 ± 3.496.4 ± 8.60.34M3-0650.36458 ± 0.008196.5059 ± 0.24842003.8 ± 45.02046.6 ± 78.10.55

Grain No.206Pb/238U207Pb/235U238U–206Pb age (Ma)235U–207Pb age (Ma)Th/UGrain No.206Pb/238U207Pb/235U238U–206Pb age (Ma)235U–207Pb age (Ma)Th/U
M3-0660.44954 ± 0.009769.7085 ± 0.32502393.2 ± 52.02407.4 ± 80.60.22Ry1-0320.01637 ± 0.000430.1131 ± 0.0086104.7 ± 2.7108.8 ± 8.30.38
M3-0670.02680 ± 0.000700.1844 ± 0.0147170.5 ± 4.5171.8 ± 13.70.32Ry1-0330.01476 ± 0.000440.1080 ± 0.010794.5 ± 2.8104.1 ± 10.30.67
M3-0680.27836 ± 0.007394.3495 ± 0.26101583.1 ± 42.01702.7 ± 102.20.29Ry1-0340.01354 ± 0.000590.0956 ± 0.016386.7 ± 3.892.7 ± 15.81.82
M3-0690.30093 ± 0.007114.6220 ± 0.21141695.9 ± 40.11753.2 ± 80.20.11Ry1-0350.01480 ± 0.000430.1039 ± 0.010094.7 ± 2.8100.4 ± 9.70.39
M3-0700.37189 ± 0.008315.9032 ± 0.22562038.3 ± 45.51961.6 ± 75.00.44Ry1-0360.01440 ± 0.000520.0929 ± 0.013492.2 ± 3.390.2 ± 13.00.61
M3-0710.27481 ± 0.007484.2010 ± 0.18921565.2 ± 42.61674.2 ± 75.40.44Ry1-0370.01287 ± 0.000390.0874 ± 0.009082.5 ± 2.585.0 ± 8.80.55
M3-0720.01279 ± 0.000580.0859 ± 0.016081.9 ± 3.783.7 ± 15.60.65Ry1-0380.01293 ± 0.001200.0828 ± 0.014082.8 ± 7.780.8 ± 13.70.54
M3-0730.03551 ± 0.001600.2404 ± 0.0436225.0 ± 10.1218.8 ± 39.70.50Ry1-0390.00981 ± 0.000890.0648 ± 0.009162.9 ± 5.763.8 ± 9.00.54
M3-0740.34292 ± 0.009405.5050 ± 0.25151900.7 ± 52.11901.3 ± 86.90.13Ry1-0400.01336 ± 0.001240.0953 ± 0.016385.5 ± 8.092.5 ± 15.81.12
M3-0750.24853 ± 0.006973.7852 ± 0.19021430.9 ± 40.11589.6 ± 79.90.49Ry1-0410.01319 ± 0.000390.0948 ± 0.011684.4 ± 2.592.0 ± 11.30.61
M3-0760.31811 ± 0.008794.9171 ± 0.23301780.5 ± 49.21805.1 ± 85.50.39Ry1-0420.01312 ± 0.000630.0898 ± 0.020184.0 ± 4.087.3 ± 19.60.75
M3-0770.02889 ± 0.001350.2111 ± 0.0193183.6 ± 8.6194.5 ± 17.80.12Site 7 (Sample 160704-04) in Komatagawa Unit (Ry2) of Ryujin Complex
M3-0780.41717 ± 0.018588.9603 ± 0.53552247.6 ± 100.12333.9 ± 139.50.57Ry2-0010.01056 ± 0.000580.0658 ± 0.017467.7 ± 3.764.7 ± 17.10.52
M3-0790.39475 ± 0.017577.3516 ± 0.44062144.8 ± 95.52155.0 ± 129.20.49Ry2-0020.01024 ± 0.000640.0703 ± 0.020465.7 ± 4.169.0 ± 20.00.74
M3-0800.27689 ± 0.012434.4336 ± 0.28051575.7 ± 70.81718.6 ± 108.70.61Ry2-0030.01430 ± 0.000320.0973 ± 0.007291.6 ± 2.094.3 ± 7.00.81
M3-0810.40293 ± 0.017978.0274 ± 0.48462182.5 ± 97.42234.0 ± 134.90.35Ry2-0040.01205 ± 0.000510.0820 ± 0.015477.2 ± 3.380.0 ± 15.00.59
M3-0820.34039 ± 0.007965.1557 ± 0.25141888.5 ± 44.21845.3 ± 90.00.34Ry2-0050.01312 ± 0.000480.0961 ± 0.014584.0 ± 3.193.2 ± 14.00.69
M3-0830.02869 ± 0.000910.2033 ± 0.0238182.3 ± 5.8187.9 ± 22.01.04Ry2-0060.35260 ± 0.007595.4637 ± 0.25511947.0 ± 41.91894.8 ± 88.50.18
M3-0840.30129 ± 0.006354.7291 ± 0.16931697.7 ± 35.81772.3 ± 63.50.37Ry2-0070.01029 ± 0.000520.0676 ± 0.014366.0 ± 3.366.4 ± 14.10.62
M3-0850.39364 ± 0.014557.5405 ± 0.40932139.7 ± 79.12177.7 ± 118.20.32Ry2-0080.01731 ± 0.000550.1248 ± 0.0110110.6 ± 3.5119.4 ± 10.50.44
M3-0860.37331 ± 0.013826.1409 ± 0.33772045.0 ± 75.71996.0 ± 109.80.18Ry2-0090.01217 ± 0.000480.0823 ± 0.010678.0 ± 3.180.3 ± 10.30.51
M3-0870.31720 ± 0.012105.1176 ± 0.31961776.1 ± 67.81839.0 ± 114.80.74Ry2-0100.01024 ± 0.000540.0712 ± 0.015165.7 ± 3.569.9 ± 14.80.48
M3-0880.29584 ± 0.011134.6848 ± 0.27741670.6 ± 62.81764.5 ± 104.50.72Ry2-0110.01551 ± 0.000580.0988 ± 0.011199.2 ± 3.795.6 ± 10.80.35
M3-0890.30734 ± 0.011864.8209 ± 0.31541727.6 ± 66.71788.5 ± 117.00.93Ry2-0120.01100 ± 0.000580.0656 ± 0.015270.5 ± 3.764.5 ± 14.90.82
M3-0900.28392 ± 0.010974.5500 ± 0.29781611.1 ± 62.21740.1 ± 113.90.45Ry2-0130.03942 ± 0.004400.2833 ± 0.0457249.2 ± 27.8253.3 ± 40.90.44
M3-0910.01459 ± 0.000720.0889 ± 0.015493.4 ± 4.686.4 ± 15.00.47Ry2-0140.01025 ± 0.001200.0627 ± 0.014765.8 ± 7.761.7 ± 14.50.61
M3-0920.02902 ± 0.000570.2068 ± 0.0135184.4 ± 3.6190.8 ± 12.40.47Ry2-0150.01190 ± 0.001420.0749 ± 0.019776.2 ± 9.173.3 ± 19.30.76
M3-0930.31623 ± 0.004994.9435 ± 0.14151771.3 ± 28.01809.7 ± 51.80.34Ry2-0160.00967 ± 0.001310.0637 ± 0.017862.0 ± 8.462.7 ± 17.50.93
M3-0940.35706 ± 0.005495.8265 ± 0.15321968.2 ± 30.31950.3 ± 51.30.45Ry2-0170.01902 ± 0.000470.1293 ± 0.0092121.5 ± 3.0123.5 ± 8.80.44
M3-0950.27993 ± 0.004334.2977 ± 0.10071591.0 ± 24.61692.9 ± 39.70.27Ry2-0180.01036 ± 0.001140.0742 ± 0.017266.4 ± 7.372.6 ± 16.80.64
M3-0960.40651 ± 0.013778.3635 ± 0.41542198.9 ± 74.52271.2 ± 112.80.37Ry2-0190.01307 ± 0.001150.0945 ± 0.018483.7 ± 7.391.7 ± 17.90.54
M3-0970.25072 ± 0.008543.7948 ± 0.19791442.2 ± 49.21591.6 ± 83.00.25Ry2-0200.01441 ± 0.001130.0973 ± 0.017992.2 ± 7.294.3 ± 17.30.38
M3-0980.31836 ± 0.011435.3902 ± 0.32541781.7 ± 64.01883.2 ± 113.70.22Ry2-0210.01159 ± 0.000460.0799 ± 0.011374.3 ± 2.978.1 ± 11.10.62
M3-0990.34825 ± 0.011895.6094 ± 0.29151926.2 ± 65.81917.5 ± 99.60.27Ry2-0220.01050 ± 0.000490.0626 ± 0.012367.3 ± 3.161.6 ± 12.10.74
M3-1000.02659 ± 0.001150.1756 ± 0.0231169.2 ± 7.3164.3 ± 21.60.91Ry2-0230.01454 ± 0.000580.1005 ± 0.014593.1 ± 3.797.3 ± 14.00.66
M3-1010.31664 ± 0.010775.0037 ± 0.25741773.3 ± 60.31819.9 ± 93.60.31Ry2-0240.33110 ± 0.009305.4844 ± 0.21611843.7 ± 51.81898.1 ± 74.80.37
M3-1020.01405 ± 0.000550.0982 ± 0.010290.0 ± 3.595.1 ± 9.90.41Ry2-0250.01285 ± 0.000670.0939 ± 0.018682.3 ± 4.391.2 ± 18.10.56
M3-1030.29647 ± 0.005214.7116 ± 0.12991673.8 ± 29.41769.2 ± 48.80.17Ry2-0260.01718 ± 0.001190.1056 ± 0.0312109.8 ± 7.6101.9 ± 30.10.39
M3-1040.48278 ± 0.0089611.4133 ± 0.36202539.4 ± 47.12557.4 ± 81.11.16Ry2-0270.03886 ± 0.001510.2803 ± 0.0361245.8 ± 9.5250.9 ± 32.30.79
M3-1050.45489 ± 0.0084910.3393 ± 0.33772417.0 ± 45.12465.5 ± 80.51.04Ry2-0280.01669 ± 0.000530.1073 ± 0.0091106.7 ± 3.4103.5 ± 8.80.44
M3-1060.34227 ± 0.006146.8732 ± 0.19941897.6 ± 34.02095.1 ± 60.80.12Ry2-0290.01353 ± 0.000530.0895 ± 0.012386.6 ± 3.487.0 ± 11.90.44
M3-1070.37280 ± 0.006747.1919 ± 0.21652042.6 ± 36.92135.4 ± 64.30.14Ry2-0300.01623 ± 0.000510.1066 ± 0.0089103.8 ± 3.3102.9 ± 8.50.58
M3-1080.39657 ± 0.007218.7743 ± 0.26262153.2 ± 39.12314.7 ± 69.30.57Ry2-0310.01217 ± 0.000450.0759 ± 0.009878.0 ± 2.974.2 ± 9.60.61
M3-1090.46478 ± 0.0077610.1766 ± 0.29582460.6 ± 41.12450.9 ± 71.20.79Ry2-0320.01210 ± 0.000480.0753 ± 0.011277.6 ± 3.173.7 ± 10.91.10
M3-1100.39449 ± 0.006457.0356 ± 0.20122143.6 ± 35.02115.9 ± 60.50.46Ry2-0330.01035 ± 0.000410.0700 ± 0.010266.4 ± 2.668.7 ± 10.00.96
M3-1110.02597 ± 0.000520.1965 ± 0.0123165.2 ± 3.3182.2 ± 11.40.51Ry2-0340.01453 ± 0.000670.0958 ± 0.019293.0 ± 4.392.9 ± 18.60.43
M3-1120.30986 ± 0.004864.9552 ± 0.12651740.0 ± 27.31811.6 ± 46.30.28Ry2-0350.01150 ± 0.000470.0805 ± 0.013673.7 ± 3.078.6 ± 13.30.76
M3-1130.03669 ± 0.001190.2772 ± 0.0371232.3 ± 7.5248.4 ± 33.30.51Ry2-0360.41908 ± 0.009638.0401 ± 0.33812256.3 ± 51.82235.5 ± 94.00.26
M3-1140.02673 ± 0.000610.2000 ± 0.0161170.0 ± 3.9185.1 ± 14.90.57Ry2-0370.01049 ± 0.000480.0667 ± 0.013767.3 ± 3.165.6 ± 13.51.20
M3-1150.01207 ± 0.000340.0874 ± 0.009777.3 ± 2.185.1 ± 9.50.98Ry2-0380.01497 ± 0.000460.0921 ± 0.010495.8 ± 2.989.5 ± 10.10.77
M3-1160.44019 ± 0.008879.4339 ± 0.39102351.5 ± 47.42381.1 ± 98.70.72Ry2-0390.01335 ± 0.000320.0909 ± 0.008285.5 ± 2.088.4 ± 8.00.26
M3-1170.02934 ± 0.000710.2106 ± 0.0172186.4 ± 4.5194.1 ± 15.90.76Ry2-0400.01286 ± 0.000450.0913 ± 0.021582.3 ± 2.988.7 ± 20.90.82
M3-1180.01595 ± 0.000390.1125 ± 0.0096102.0 ± 2.5108.2 ± 9.20.51Ry2-0410.01185 ± 0.000350.0728 ± 0.012375.9 ± 2.271.3 ± 12.10.53
M3-1190.02722 ± 0.000580.2023 ± 0.0129173.1 ± 3.7187.0 ± 11.90.43Ry2-0420.35483 ± 0.007466.1989 ± 0.30381957.6 ± 41.22004.2 ± 98.20.29
Site 6 (Sample 160704-05) in Sohgawa Unit (Ry1) of Ryujin ComplexRy2-0430.01398 ± 0.001140.0879 ± 0.021089.5 ± 7.385.5 ± 20.40.81
Ry1-0010.01688 ± 0.000680.1121 ± 0.0225107.9 ± 4.3107.9 ± 21.60.56Ry2-0440.01530 ± 0.000640.0959 ± 0.015297.9 ± 4.192.9 ± 14.70.80
Ry1-0020.01499 ± 0.000770.0939 ± 0.022695.9 ± 4.991.1 ± 21.90.68Ry2-0450.01051 ± 0.000440.0686 ± 0.010767.4 ± 2.867.4 ± 10.50.87
Ry1-0030.01331 ± 0.000470.0964 ± 0.013485.2 ± 3.093.4 ± 13.00.59Ry2-0460.39638 ± 0.011017.8925 ± 0.27772152.4 ± 59.82218.7 ± 78.10.11
Ry1-0040.04290 ± 0.001470.3194 ± 0.0417270.8 ± 9.3281.4 ± 36.80.59Ry2-0470.01545 ± 0.000440.0990 ± 0.013298.9 ± 2.895.9 ± 12.80.25
Ry1-0050.06143 ± 0.001550.4831 ± 0.0372384.3 ± 9.7400.2 ± 30.80.82Ry2-0480.40526 ± 0.005687.9106 ± 0.25422193.2 ± 30.72220.8 ± 71.40.65
Ry1-0060.01350 ± 0.000450.0974 ± 0.015886.5 ± 2.994.4 ± 15.30.61Ry2-0490.02567 ± 0.000430.1825 ± 0.0113163.4 ± 2.8170.2 ± 10.60.41
Ry1-0070.01817 ± 0.000590.1213 ± 0.0157116.1 ± 3.8116.3 ± 15.00.47Ry2-0500.01587 ± 0.000480.1110 ± 0.0150101.5 ± 3.1106.9 ± 14.50.40
Ry1-0080.01728 ± 0.000500.1235 ± 0.0102110.4 ± 3.2118.2 ± 9.80.38Ry2-0510.01343 ± 0.000280.0885 ± 0.007686.0 ± 1.886.1 ± 7.40.54
Ry1-0090.01557 ± 0.000500.1133 ± 0.015299.6 ± 3.2109.0 ± 14.60.49Ry2-0520.04000 ± 0.001020.2721 ± 0.0254252.8 ± 6.5244.4 ± 22.80.41
Ry1-0100.01404 ± 0.000600.1014 ± 0.019189.9 ± 3.998.1 ± 18.40.69Ry2-0530.01286 ± 0.000380.0909 ± 0.011082.4 ± 2.488.4 ± 10.70.91
Ry1-0110.01258 ± 0.000550.0772 ± 0.016180.6 ± 3.675.5 ± 15.70.54Ry2-0540.35297 ± 0.006905.7242 ± 0.20421948.8 ± 38.11935.0 ± 69.00.56
Ry1-0120.35684 ± 0.005885.5728 ± 0.25251967.2 ± 32.41911.8 ± 86.60.22Ry2-0550.01380 ± 0.000500.0944 ± 0.014888.3 ± 3.291.6 ± 14.30.55
Ry1-0130.01472 ± 0.000280.0999 ± 0.006994.2 ± 1.896.7 ± 6.70.97Ry2-0560.01180 ± 0.000260.0774 ± 0.006075.6 ± 1.775.7 ± 5.90.41
Ry1-0140.01769 ± 0.000410.1214 ± 0.0110113.1 ± 2.6116.3 ± 10.60.58Ry2-0570.01594 ± 0.000380.1019 ± 0.0091102.0 ± 2.498.5 ± 8.80.29
Ry1-0150.01539 ± 0.000430.0997 ± 0.013298.5 ± 2.896.5 ± 12.80.44Ry2-0580.28300 ± 0.006004.4133 ± 0.22321606.4 ± 34.11714.8 ± 86.70.52
Ry1-0160.01704 ± 0.000570.1116 ± 0.0076108.9 ± 3.7107.4 ± 7.40.46Site 8 (Sample 160704-03) in Yunohara Unit (Ry3) of Ryujin Complex
Ry1-0170.39488 ± 0.012717.1334 ± 0.29582145.4 ± 69.02128.1 ± 88.30.35Ry3-0010.32395 ± 0.014905.1223 ± 0.34771809.0 ± 83.21839.7 ± 124.90.19
Ry1-0180.01345 ± 0.000610.0806 ± 0.015986.2 ± 3.978.7 ± 15.60.57Ry3-0020.35419 ± 0.016765.9175 ± 0.41211954.6 ± 92.51963.7 ± 136.70.14
Ry1-0190.40363 ± 0.007976.8531 ± 0.32262185.7 ± 43.12092.5 ± 98.50.18Ry3-0030.01150 ± 0.000330.0752 ± 0.007073.7 ± 2.173.7 ± 6.80.42
Ry1-0200.01017 ± 0.000420.0610 ± 0.011265.2 ± 2.760.1 ± 11.10.99Ry3-0040.01349 ± 0.000520.0894 ± 0.014186.4 ± 3.386.9 ± 13.70.69
Ry1-0210.01240 ± 0.000360.0786 ± 0.008979.5 ± 2.376.8 ± 8.70.83Ry3-0050.32864 ± 0.008515.2744 ± 0.25191831.8 ± 47.41864.7 ± 89.10.35
Ry1-0220.01124 ± 0.000330.0777 ± 0.008872.1 ± 2.176.0 ± 8.61.28Ry3-0060.01104 ± 0.000400.0736 ± 0.009770.8 ± 2.672.1 ± 9.50.58
Ry1-0230.01557 ± 0.000340.1065 ± 0.007499.6 ± 2.2102.8 ± 7.20.28Ry3-0070.01700 ± 0.000460.1243 ± 0.0079108.6 ± 2.9119.0 ± 7.50.37
Ry1-0240.03569 ± 0.000900.2687 ± 0.0192226.1 ± 5.7241.7 ± 17.30.30Ry3-0080.01077 ± 0.000330.0678 ± 0.006569.1 ± 2.166.6 ± 6.40.55
Ry1-0250.34481 ± 0.008495.5609 ± 0.30041909.8 ± 47.01910.0 ± 103.20.87Ry3-0090.01718 ± 0.000600.1235 ± 0.0149109.8 ± 3.8118.2 ± 14.20.37
Ry1-0260.01163 ± 0.000520.0795 ± 0.015174.5 ± 3.377.7 ± 14.70.55Ry3-0100.01251 ± 0.000430.0812 ± 0.009980.1 ± 2.779.3 ± 9.70.32
Ry1-0270.01514 ± 0.000620.1113 ± 0.018296.9 ± 4.0107.2 ± 17.50.69Ry3-0110.01318 ± 0.000490.0821 ± 0.010584.4 ± 3.280.1 ± 10.20.63
Ry1-0280.04386 ± 0.001360.2904 ± 0.0324276.7 ± 8.6258.9 ± 28.90.46Ry3-0120.01276 ± 0.000510.0864 ± 0.012381.7 ± 3.384.1 ± 12.00.28
Ry1-0290.01323 ± 0.000600.0908 ± 0.017384.7 ± 3.888.2 ± 16.90.48Ry3-0130.35532 ± 0.010165.8872 ± 0.24741959.9 ± 56.01959.3 ± 82.30.32
Ry1-0300.34661 ± 0.007895.6171 ± 0.22041918.4 ± 43.71918.7 ± 75.30.25Ry3-0140.01230 ± 0.000400.0813 ± 0.006878.8 ± 2.579.4 ± 6.70.36
Ry1-0310.01358 ± 0.000360.0987 ± 0.010186.9 ± 2.395.6 ± 9.80.63Ry3-0150.01626 ± 0.000570.1144 ± 0.0114104.0 ± 3.7109.9 ± 10.90.36

Grain No.206Pb/238U207Pb/235U238U–206Pb age (Ma)235U–207Pb age (Ma)Th/UGrain No.206Pb/238U207Pb/235U238U–206Pb age (Ma)235U–207Pb age (Ma)Th/U
Ry3-0160.01320 ± 0.000570.0801 ± 0.010584.5 ± 3.678.2 ± 10.20.43Ry3-0300.01264 ± 0.000300.0856 ± 0.009681.0 ± 1.983.4 ± 9.40.62
Ry3-0170.03781 ± 0.001130.2906 ± 0.0200239.2 ± 7.1259.0 ± 17.80.60Ry3-0310.15669 ± 0.004671.7004 ± 0.1571938.4 ± 28.01008.7 ± 93.21.35
Ry3-0180.01577 ± 0.000830.0995 ± 0.0228100.9 ± 5.396.3 ± 22.10.74Ry3-0320.01299 ± 0.001490.0850 ± 0.019683.2 ± 9.682.8 ± 19.10.49
Ry3-0190.00998 ± 0.000230.0671 ± 0.005364.0 ± 1.565.9 ± 5.30.43Ry3-0330.26867 ± 0.005234.2498 ± 0.14771534.0 ± 29.91683.6 ± 58.50.26
Ry3-0200.01294 ± 0.000440.0941 ± 0.012682.9 ± 2.891.3 ± 12.30.57Ry3-0340.01264 ± 0.000730.0816 ± 0.011281.0 ± 4.779.6 ± 11.00.56
Ry3-0210.01070 ± 0.000460.0715 ± 0.011268.6 ± 3.070.1 ± 11.01.04Ry3-0350.01129 ± 0.000490.0765 ± 0.008372.4 ± 3.174.8 ± 8.10.34
Ry3-0220.01778 ± 0.000840.1218 ± 0.0138113.6 ± 5.4116.7 ± 13.20.31Ry3-0360.32362 ± 0.005705.1530 ± 0.13711807.4 ± 31.81844.8 ± 49.10.10
Ry3-0230.31903 ± 0.009115.2675 ± 0.22671785.0 ± 51.01863.5 ± 80.20.19Ry3-0370.01240 ± 0.000390.0790 ± 0.008679.5 ± 2.577.2 ± 8.40.51
Ry3-0240.29031 ± 0.008384.7035 ± 0.21011643.1 ± 47.41767.8 ± 79.00.41Ry3-0380.02713 ± 0.000850.2053 ± 0.0207172.6 ± 5.4189.6 ± 19.10.18
Ry3-0250.01553 ± 0.000780.1050 ± 0.010199.4 ± 5.0101.4 ± 9.80.29Ry3-0390.00978 ± 0.000330.0673 ± 0.008462.7 ± 2.166.1 ± 8.31.51
Ry3-0260.01314 ± 0.000360.0896 ± 0.005484.1 ± 2.387.1 ± 5.30.36Ry3-0400.01301 ± 0.000420.0828 ± 0.009883.3 ± 2.780.8 ± 9.60.84
Ry3-0270.01554 ± 0.000330.0998 ± 0.010199.4 ± 2.196.6 ± 9.80.56Ry3-0410.01274 ± 0.000420.0882 ± 0.010181.6 ± 2.785.9 ± 9.80.48
Ry3-0280.35079 ± 0.003855.8962 ± 0.26971938.4 ± 21.21960.6 ± 89.70.25Ry3-0420.01322 ± 0.000580.0892 ± 0.016584.7 ± 3.786.8 ± 16.10.66
Ry3-0290.01510 ± 0.000360.0995 ± 0.011496.6 ± 2.396.3 ± 11.00.75Ry3-0430.01090 ± 0.000410.0784 ± 0.011069.9 ± 2.676.7 ± 10.81.25

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Written By

Tetsuya Tokiwa, Makoto Takeuchi, Yusuke Shimura, Kazuho Shobu, Akari Ota, Koshi Yamamoto and Hiroshi Mori

Submitted: June 29th, 2016 Reviewed: February 20th, 2017 Published: June 21st, 2017