Formation · Cambrian
Wheeler Shale
Miaolingian unit, Utah
The Wheeler Shale of the House Range, Utah, is the world's most prolific trilobite locality: Elrathia kingii by the million, the larger Asaphiscus wheeleri, agnostids and the spiny Olenoides. Elrathia are cheap, genuine and abundant, but they are also enhanced: outlines are sometimes scribed, black paint or shoe polish applied to raise contrast, and cast-resin 'trilobites' glued onto real shale appear at shows. A fresh Wheeler trilobite is dark grey to black on light grey shale with a slightly convex, three-dimensional shell.
| Country | United States |
|---|---|
| Region | Utah |
| Age | Drumian, Miaolingian |
| Age range | ~507–500 Ma |
| Macrostrat rank | Fm· Macrostrat |
| Macrostrat age | 503–502 Ma· Macrostrat |
| PBDB collections | 59 collections, 319 occurrences· Paleobiology Database |
Collecting and legality
The House Range outcrops are BLM land where casual collecting of invertebrates for personal use is allowed (hand tools, reasonable amounts, no sale); the commercial Elrathia trade comes from private mining claims and pay-to-dig quarries such as U-Dig near Delta, whose finds you may keep and sell.
Lithology and setting
Grey calcareous shale and thin limestone deposited in the deep House Range Embayment; the fossiliferous zone is a few metres of dark, fissile shale.
Commonly recorded taxa (PBDB)
Genera most often recorded from this unit in the Paleobiology Database (first 200 occurrences): Peronopsis (21), Ptychagnostus (19), Triplagnostus (15), Elrathia (14), Itagnostus (13), Choia (7), Ptychoparella (7), Bolaspidella (5), Chancelloria (5), Olenoides (5), Brachyaspidion (4), Diagoniella (4), Gogia (4), Modocia (4), Pentagnostus (Meragnostus) (4).
Source: Paleobiology Database
Collecting rules
Elsewhere
- Macrostrat: 74382
- macrostratConcept: 11120
- PBDB: strata:Wheeler
- Wikidata: Q2566654
- Macrostrat stratigraphic name
- PBDB occurrences for this unit
- Wikipedia: Wheeler Shale
- Mindat: Wheeler Shale
Cite this article
Stratum Study. "Wheeler Shale" (Formation). Stratum Study pack 2026.09, as of 2026-09-19. https://stratum.black/study/formations/wheeler-shale. Accessed 2026-09-20.
@misc{stratum-wheeler-shale,
title = {Wheeler Shale},
author = {{Stratum Study}},
howpublished = {\url{https://stratum.black/study/formations/wheeler-shale}},
year = {2026},
note = {Formation article, Stratum Study pack 2026.09, as of 2026-09-19; sources: stratum, macrostrat, pbdb, wikidata, commons. Accessed 2026-09-20.}
} Citations carry the pack version and the article's as-of date so they resolve to the same text later. The facts themselves belong to the sources listed below; cite those for the science.