Laberge Group Ammonite Zones and Stratigraphy in Southern Yukon

New ammonite collections from the Lower to Middle Jurassic Laberge Group in the Whitehorse area are assigned to nine ammonite zones or assemblages. The data, published by the Government of Yukon, shows the group contains nearly all zones from Upper Sinemurian to Lower Bajocian stages, with some gaps in Hettangian and Lower Sinemurian. Deposition of conglomerates and fine-grained clastics is analyzed across the Takhini and Fish Lake areas.

Use Cases

• Establish ammonite-based chronostratigraphy based on the nine assigned zones or assemblages.
• Analyze depositional patterns of conglomerates and fine-grained clastics across different geographic areas.
• Correlate regional stratigraphy using guide ammonites illustrated in the dataset.
• Study the temporal distribution of specific ammonite taxa like Fontanelliceras and Canavaria.
• Model relative sea-level changes during the Early Jurassic based on conglomerate deposition events.

Strengths

• Data is structured around nine ammonite zones or assemblages, providing a clear stratigraphic framework.
• Geographic coverage is specified for the Whitehorse map area (105D), Takhini area, and Fish Lake area.
• Temporal coverage spans specific Jurassic stages from Upper Sinemurian to Lower Bajocian.
• Includes illustrated guide ammonites for taxonomic reference.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• The presence of Hettangian and Lower Sinemurian stages is not adequately confirmed.

Provenance

Source

Government of Yukon

Collection Method

New ammonite collections supplemented by other published and critically revised data.

Time Range

Lower to Middle Jurassic (Hettangian? to Bajocian stages)

Freshness

Last updated 2026-04-17 16:12:01.455627; freshness should be verified.

Geography

Laberge Group, Whitehorse Map Area (105D), Southern Yukon, including Takhini and Fish Lake areas.