Fig 1.
Map of Canada (inset) and satellite image showing location of the Strathcona Fiord study area and measured section.
Fig 2.
Images of the Strathcona Fiord Fossil Forest and fossil vertebrate site P201088-2(NU).
(A) P201088-2(NU) is less than a meter stratigraphically above the coal containing the fossil forest; (B) and (C) show close-ups of petrified tree stumps in the fossil forest.
Fig 3.
Strathcona Fiord Section showing stratigraphic level of fossil vertebrate locality P2011088-2 (NU) and Strathcona Fiord Fossil Forest in the coal directly below it.
Sedimentology is described in the text.
Fig 4.
Tooth fragments from locality P201088-2(NU) at the Strathcona Fiord Fossil Forest site on central Ellesmere Island, Nunavut.
(A) NUFV 2092B. (B) NUFV 2092E.
Fig 5.
Orientation of the three traditional planes of section used to study mammalian tooth enamel microstructure from [18].
Fig 6.
SEM images of the tangential section of NUFV 2092E.
(A) Cross-section through prisms; the prism sheath is dark and looks like a trench around each prism because it has been etched away. (B) Close-up of prisms and interprismatic matrix which are comprised of fine, needle-like crystallites. P, prism.
Fig 7.
SEM image of enamel of NUFV 2092B in horizontal section.
(A) Three enamel zones are evident—a very thin Inner Zone of radial enamel (in some places), a thick Middle Zone comprised of elongate bodies of prisms, and a thin Outer Zone. (B) Higher magnification SEM image showing area outlined by white square in (A); elongate bodies (eb) are comprised of steeply-dipping or rising prisms, and are separated from one another by transitional zones (tz) made up of horizontal (or nearly so) prisms. Irregular-shaped grains on SEM images are an artifact of sample preparation process.
Fig 8.
Uncoated tangential section of NUFV 2092E under a light microscope (A) and higher magnification (B).
In both images, occlusal surface is towards the top and source of light is from the bottom. EDJ, Enamel-Dentine Junction; OES, outer enamel surface.
Fig 9.
SEM images of vertical section of outer zone of NUFV 2092B (A and B), and uncoated tangential sections of NUFV 2092B (C) and Yukon Government (YG) 514.12 (D), rhinocerotoid enamel from [26].
In (A) the region outlined by white square is magnified in (B). OES, outer enamel surface. (C) Magnified uncoated tangential section of NUFV 2092E under a light microscope, compared to (D) uncoated tangential section of YG514.12, enamel of a Miocene rhinocerotoid from the Yukon, Canada under a light microscope.