Field Guides/Sudbury/Geology & Discovery
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Best WindowMay through October for above-ground geology stops; Dynamic Earth and Going Underground operate year-round
Variantscave-tour-sightseeing
RegionSudbury, Ontario

Geology & Discovery.

The Sudbury Basin is the second-largest confirmed meteorite impact structure on Earth — a ~1.85-billion-year-old crater whose original diameter is estimated at 200–260 km, eroded today to a ~60 × 30 km elliptical basin whose rim runs through the City of Greater Sudbury. The Sudbury Igneous Complex around the rim hosts one of the world's most productive nickel-copper-platinum-group ore bodies, mined commercially since 1883.

Geology & Discovery in Sudbury
01 — What to know

The brief.

Dynamic Earth's Going Underground tour at the Big Nickel site is the canonical interpretive descent — roughly seven storeys into a former Inco demonstration drift. The above-ground geology — Sudbury Igneous Complex norite and granophyre, footwall breccias, Onaping Formation impact debris, and shatter-cone outcrops — is interpreted at Dynamic Earth and on outdoor signage at A.Y.

Jackson Lookout / Onaping Falls and along basin-rim drives. The regreening program (1978–present) restored ~3,400 ha of smelter-barren landscape; the program received a UN Local Government Honours Award in 1992 and is widely cited in restoration ecology.

Mine-experience tours are operated by Dynamic Earth and require timed entry. Sudbury Basin geology runs year-round; the surface lookout points read best May through October.

02 — Locations

5. places.

  1. 01

    Sudbury Basin / Sudbury Igneous Complex

    The rim runs through Greater Sudbury; outcrops and lookouts around the basin.

  2. 02

    Dynamic Earth — Going Underground

    Mine-tour descent into a former Inco demonstration drift at the Big Nickel site.

  3. 03

    Big Nickel surface plaza

    Outdoor geology and mining interpretation at the Dynamic Earth site.

  4. 04

    A.Y. Jackson Lookout / Onaping Falls

    Surface exposure of Sudbury Basin geology along the Onaping River, ~50 km northwest of downtown.

  5. 05

    Regreening corridors

    Liming-and-seeding restoration sites visible across the basin, particularly along Hwy 17 west and the Hwy 144 corridor.

03 — Conditions

Today's read.

Air Quality
22
eu-aqi · low
UV Index
0.7
scale 0–11
Humidity
75%
relative
Visibility
21.9 km
clear
Temp
+1.8°
H 11° · L -2°
Sun
05:53 / 20:47
14h 54m daylight
A+
Prime conditions for geology & discovery

Cold but firm — winter-ready conditions · light winds · clean air.

More from Sudbury

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