Illtyd Formation

Illtyd Formation
Stratigraphic range: Cambrian
Type Formation
Underlies Slats Creek Fm
Location
Region Yukon
Country Canada

The Illtyd Formation is an up to 1000-m thick geologic formation in Yukon. It preserves fossils dating back to the Dyerian subdivision of the Cambrian period, which spans the Stage 3 / Stage 4 boundary; it's considered to belong to the mid-upper Bonnia-ollenellus trilobite Zone. Top of the unit corresponds, more or less, to the top of Stage 4.[1][2] These fossils include Lower Cambrian trilobites'.[3]

The type section is in the Wernecke Mtns; it corps out also in and to the S/SW of the Rochardson Moutnars . IT possibly corresponds to the Sekwi Fm in the Macxkenzie mtns.[4]

Lowermost of the Palaeozic units west of the Richardson Mtns, angular unconformity at base, overlying various Precambrian units. Silty limestones and massive dolostones. In places rhythmically bedded. Colour: Tan, brownish grey muds; sanier layers orange. Upper layers include oolites and oncolites. Trace fossils include burrows and 'worm trails'. In some places unit is massively faulted and altered / weathered, approaching marble grade metamorphism near faults. [5]

See also

References

  1. ↑
  2. ↑ http://escholarship.org/uc/item/8fq03184
  3. ↑ Lower Cambrian trilobites from the Illtyd formation, Wernecke mountains, Yukon territory WH Fritz - 1991 - Ottawa
  4. ↑
  5. ↑ http://ftp.geogratis.gc.ca/pub/nrcan_rncan/publications/ess_sst/210/210998/bu_538.pdf Geol Soc Can Bull 538 ... Lower Palasozoic strat of Northern Yukon Territory and noerthweaester district of mackenzine DW Morrow 1999 And other contributors. ISBN = 0-660-17808-7 http://ftp.geogratis.gc.ca/pub/nrcan_rncan/publications/ess_sst/210/210998/bu_538.pdf


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