Geochronology Standards

Unfortunately, we are no longer able to provide the range of standards that we offered previously, due to travel restrictions across the globe that have resulted in a lack of access to original rock material for processing. As of June 2021, we only have small amounts (<5 kg) of Fish Canyon Tuff, FC1 (Duluth –zircon), and FC5 (Duluth – apatite) left to be processed. As soon as possible we will attempt to restock our supplies in the hope that we might start providing further options during late 2021 or early 2022.

As of June 10, 2021:
red = plenty available.
blue = small amount available – maximum 250mg order.
black = not available.

Mount Dromedary (apatite, titanite, and zircon)
Mount McClure (apatite, titanite, and zircon)
Fish Canyon Tuff (apatite, titanite, and zircon)
Duluth Complex (apatite and zircon)
Durango (apatite only)
Tardree Rhyolite (zircon only)

Please contact Paul about standard availability and ordering.

Academic Labs
0.25 grams (~60 mounts): $350.00 per aliquot $175.00 per second mineral
0.50 grams (~120 mounts): $650.00 per aliquot $325.00 per second mineral
1.00 grams (~240 mounts): $1,200.00 per aliquot $600.00 per second mineral

Commercial Labs
0.25 grams (~60 mounts): $500.00 per aliquot $250.00 per second mineral
0.50 grams (~120 mounts): $900.00 per aliquot $450.00 per second mineral
1.00 grams (~240 mounts): $1,700.00 per aliquot $850.00 per second mineral

Standard Standard Age (±2s) Reference
MD Mount Dromedary 99.12 ± 0.14 Ma Renne et al., 1998
MM Mount McClure 523.51 ± 1.47 Ma Schoene and Bowring, 2006
IF Fish Canyon Tuff 28.201 ± 0.012 Ma Lanphere et al., 2001; Kuiper et al., 2008
TEM2* Temora2, Middledale gabbroic diorite 416.78 ± 0.33 Ma Black et al., 2004
Dur Durango 31.44 ± 0.018 Ma McDowell et al. 2005
FC1 Duluth complex 1099.0 ± 0.6 Ma Paces and Miller, 1993
TR Tardree Rhyolite 61.23 ± 0.11 Ma Dave Chew, personal communication

*GSS does not have access to standard material.

References Cited

Black, L.P., Kamo, S.L., Allen, C.M., Davis, D.W., Aleinikoff, J.N., Valley, J.W., Mundil, R., Campbell, I.H., Korsch, R.J., Williams, I.S., and Foudoulis, C. 2004. Improved 206 Pb/238 U microprobe geochronology by the monitoring of trace-element-related matrix effect; SHRIMP, ID-TIMS, ELA-ICP-MS and oxygen isotope documentation for a series of zircon standards. Chemical Geology, 205, p.15-140

Kuiper, K.F., Deino, A., Hilgen, P.J., Krijgsman, W., Renne, P.R., and Wijbrans, J.R., 2008. Synchronizing rock clocks of Earth history. Science, 320, p. 500-504.

Lanphere, M.A. and Baadsraard, H., 2001. Precise K-Ar, 40 Ar/39 Ar, Rb-Sr and U-Pb mineral ages from the 27.5 Ma Fish Canyon Tuff reference standard. Chemical Geology, 175, p. 653-671.

McDowell, F.W., McIntosh, W.C., and Farley, K.A., 2005. A precise 40Ar-39Ar reference age for the Durango apatite (U-Th)/He and fission trackdating standard. Chemical Geology, 214, p. 249-263

Paces, J.B. and Miller, J.D., 1993. Precise UPb ages of Duluth Complex and related mafic intrusions, northeastern Minnesota: Geochronological insights to physical, petrogenic, paleomagnetic, and tectonomagmatic processes associated with the 1.1 Ga Midcontinent Rift System. Journal of Geophysical Research, 98, no. B8, p. 13997-14013.

Renne, P.R., Swisher, C.C., Deino, A.L., Karner, D.B., Owens, T.L., and DePaolo, D.J., 1998. Intercalibration of standards, absolute ages and uncertainties in 40 Ar/39 Ar dating. Chemical Geology, 45, p. 117-152.

Schoene, B., and Bowring, S.A., 2006. U–Pb systematics of the McClure Mountain syenite: thermochronological constraints on the age of the 40Ar/39Ar standard MMhb. Contributions to Mineralogy and Petrology, 151, p. 615-630.