GSA Data Repository 2018006 New U/Pb Dates Reveal a Paleogene Origin of the Modern SE Asia Biodiversity 'Hotspot' Linnemann, U. 1,* , Su, T. 2, , Kunzmann, L. 1 , Spicer, R.A. 3,4 , Ding, W.-N 2,5 , Spicer, T.E.V. 4 , Zieger, J. 1 , Hofmann, M. 1 , Moraweck, K. 1 , Gärtner, A. 1 , Gerdes, A. 6 , Marko, L. 6 , Zhang, S.- T. 7 , Li, S.-F. 2 , Tang, H. 2,4 , Huang, J. 2,4 , Mulch, A. 6,8 , Mosbrugger, V. 9 , Zhou, Z.-K. 2 Methods (U-Th-Pb isotopes, Hf isotopes, geochemistry, plant fossils) Zircon concentrates were separated from 1 kg samples at the Senckenberg Naturhistorische Sammlungen Dresden (Museum für Mineralogie und Geologie) by crushing (jaw crusher), sieving, heavy mineral separation by heavy liquid (LST), and by making use of a magnetic separator. Final selection of the zircon grains for U-Pb dating was achieved by hand-picking under a binocular microscope. Zircon grains of all grain sizes and morphological types were selected, mounted in resin blocks and polished to half their thickness. Concerning stratigraphic ages, the stratigraphic time scale of Ogg et al. (2016) has been used. Zircons were analyzed for U, Th, and Pb isotopes by LA-SF ICP-MS techniques at the Museum für Mineralogie und Geologie (GeoPlasma Lab, Senckenberg Naturhistorische Sammlungen Dresden), using a Thermo-Scientific Element 2 XR sector field ICP-MS coupled to a New Wave UP-193 Excimer Laser System. A teardrop-shaped, low volume laser cell was used to enable sequential sampling of heterogeneous grains (e.g., growth zones) during time resolved data acquisition. Each analysis consisted of approximately 15 s background acquisition followed by 30 s data acquisition, using a laser spot-size of 25 and 35
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GSA Data Repository 2018006 - Geological Society of Americaµm, respectively. A common-Pb correction based on the interference- and background-corrected 204Pb signal and a model Pb
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GSA Data Repository 2018006 New U/Pb Dates Reveal a Paleogene Origin of the Modern SE Asia Biodiversity
Figure DR 11. Geochemical data of samples LS1-3 in different discrimination plots. Top:
SiO2-Na2O+K2O diagram (Peacock, 1931). Bottom: Log Y - Log Nb diagram (Pearce et al.,
1984) (WPG-within-plate granite, VAG + syn COLG-volcanic arc and syn-collision granites,
ORG - oceanic ridge granite).
Figure DR 12. Geochemical data of samples LS1-3 in different discrimination plots. Top:
Rare Earth Elements normalized against the C1 condrite (normalizing factors from
(McDonough and Sun, 1995). Bottom: Spider diagram showing a plot of different trace and
Rare Earth Elements against the C1 condrite (normalizing factors from (McDonough and Sun,
1995).
Supplementary Table DR1: LA-SF-ICP-MS U-Pb-Th data of magmatic zircon from tuff samples LS1, LS2, and LS3, Luhe site, Yunnan, China, Xiaolongtan Formation, Lühe Basin, coordinates: 25.141627 °N, 101.373840 °E, 1890 m amsl. Recommended ages in the range of concordance of 90-110%
207Pba Ub Pbb Thb 206Pbc 206Pbc 2 207Pbc
2 207Pbc 2 rhod 206Pb 2 207Pb 2
Number (cps) (ppm) (ppm) U 204Pb 238U % 235U % 206Pb % 238U (Ma) 235U (Ma) conc %
a within-run background-corrected mean 207Pb signal in counts per second b U and Pb content and Th/U ratio were calculated relative to GJ-1 and are accurate to approximately 10%. c corrected for background, mass bias, laser induced U-Pb fractionation and common Pb (if detectable, see analytical method) using Stacey & Kramers (1975) model Pb composition. 207Pb/235U calculated using 207Pb/206Pb/(238U/206Pb × 1/137.88). Errors are propagated by quadratic addition of within-run errors (2SE) and the reproducibility of GJ-1 (2SD). d Rho is the error correlation defined as err206Pb/238U/err207Pb/235
Supplementary Table DR2: LA-MC-ICP-MS Lu-Hf data of detrital zircon from samples LS1, LS2, and LS3, n = 13, tuff layers, Luhe site, Yunnan, China, Xiaolongtan Formation, Lühe Basin, coordinates: 25.141627 °N, 101.373840 °E, 1890 m amsl.
176Yb/177Hf a ±2 176Lu/177Hf a ±2 178Hf/177Hf 180Hf/177Hf SigHf b 176Hf/177Hf ±2c 176Hf/177Hf(t)
Quoted uncertainties (absolute) relate to the last quoted figure. The effect of the inter-element fractionation on the Lu/Hf was estimated to be about 6 % or less based on analyses of the GJ-1 zircon. Accuracy and reproducibilty was checked by repeated analyses (n = 4) of reference zircon GJ-1). (a) 176Yb/177Hf = (176Yb/173Yb)true x (173Yb/177Hf)meas x (M173(Yb)/M177(Hf))
isotope. The 176Lu/177Hf were calculated in a similar way by using the 175Lu/177Hf and (Yb). (b) Mean Hf signal in volt. (c) Uncertainties are quadratic additions of the within-run precision and the daily reproducibility of the 40ppb-JMC475 solution. Uncertainties for the JMC475 quoted at 2SD (2 standard deviation). (d) Initial 176Hf/177Hf and Hf calculated using the apparent Pb-Pb age determined by LA-ICP-MS dating (see column f), and the CHUR parameters: 176Lu/177Hf = 0.0336, and 176Hf/177Hf = 0.282785 (Bouvier et al., 2008). (e) Two stage model age in billion years using the measured 176Lu/177Hf of each spot (first stage = age of zircon), a value of 0.0113 for the average continental crust (second stage), and the depleted mantle (DM) 176Lu/177Hf and 176Hf/177Hf of 0.0384 and 0.283165, respectively (Chauvel et al., 2008) (f) U-Pb and Pb-Pb ages determined by LA-SF-ICP-MS. If the zircon age is younger than 1Ga, the 206Pb-238U age is preferred. The 207Pb-206Pb is used in the case the zircon age is older than 1 Ga.
Supplementary Table DR3: Major and trace elements including REE of volcanic ash samples LS1, LS2, and LS3, Lühe Basin, Yunnan, China, coordinates: 25.141627 °N, 101.373840 °E, 1890 m amsl. Major Elements (%) (anhydrous) LS1 LS2 LS3 SiO2 63.59 63.26 62.05 Al2O3 18.46 20.48 20.04 Fe2O3tot 2.97 2.08 6.20 FeOtot 2.67 1.87 5.97 MnO 0.009 0.009 0.012 MgO 0.66 1.0 1.17 CaO 1.86 1.22 1.04 Na2O 3.77 2.57 2.32 K2O 5.43 4.53 4.32 TiO2 0.64 0.89 0.81 P2O5 2.61 3.02 2.04 Trace Elements (ppm) Cr 150 120 110 Ni 70 70 30 Zn 50 150 70 Rb 136 137 117 Sr 6741 6450 5079 Y 45 46 44 Nb 16 22 15 Cs 2 6 7 Ba 10040 9236 6416 Ta 1 1 1 Pb 57 97 24 Th 42 49 40 U 8 10 6 Rare Earth Elements (ppm) La 226 246 453 Ce 478 513 981 Pr 51 54 91 Nd 196 195 318 Sm 29 30 44 Eu 7.5 7.1 10.1 Gd 21 21 29 Tb 2.3 2.5 3.1 Dy 11 12 13 Ho 1.6 1.8 1.8 Er 3.8 4.4 4.2 Tm 0.44 0.53 0.48 Yb 2.2 2.9 2.6 Lu 0.26 0.35 0.33
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