A high-precision U–Pb age constraint on the Rhynie Chert Konservat-Lagerstätte: time scale and other implications S.F. Parry S.R. Noble Q.G. Crowley C.H. Wellman 10.6084/m9.figshare.3452846 https://geolsoc.figshare.com/articles/journal_contribution/A_high-precision_U_Pb_age_constraint_on_the_Rhynie_Chert_Konservat-Lagerst_tte_time_scale_and_other_implications/3452846 <p>An isotope dilution thermal ionization mass spectrometry U–Pb zircon age of 411.5 ± 1.3 Ma obtained from an andesitic lava occurring within the Lower Devonian Rhynie Outlier (Aberdeenshire, NE Scotland) effectively dates the Rhynie Chert Konservat-Lagerstätte. Biostratigraphical constraints on the Rhynie Chert-bearing succession indicate that this age lies within the interval early (but not earliest) Pragian–(?)earliest Emsian. Accordingly, the Pragian–Emsian boundary must post-date or closely approximate to 411.5 ± 1.3 Ma, while the Lochkovian–Pragian boundary must predate 411.5 ± 1.3 Ma. Integration of this new high-precision age with an improved temporal framework for late Caledonian intrusive activity in NE Scotland suggests that the Rhynie hot-spring system (the ‘parental' hydrothermal system to the Rhynie cherts) was unrelated to any ‘Newer Granite' intrusion. Rhynie was instead powered by a basaltic andesite magma whose generation and ascent were directly linked to the transcurrent fault movements responsible for the formation of the Rhynie basin. </p> 2016-06-21 10:21:43 1.3 Devonian Rhynie Outlier Ma transcurrent fault movements NE Scotland basaltic andesite magma 411.5 Geology