Wizard Island: The Volcanic Cinder Cone in Crater Lake
Wizard Island** is a **perfectly formed volcanic cinder cone** rising **763 ft (233 m) above Crater Lake's surface** (summit elevation 6,933 ft / 2,113 m) in **Crater Lake National Park, Oregon**. It is the **most prominent post-caldera feature** within the caldera of **Mount Mazama**, which collapsed ~7,700 years ago (VEI 7 eruption).
Formation: A Volcano Within a Volcano
- Mazama Climactic Eruption (~5677 BCE): **50–70 km³ magma erupted.** Magma chamber roof collapsed → **6×8 km caldera**.
- Post-Caldera Activity (within centuries): **Residual magma** erupted through **ring fractures** on caldera floor.
- Wizard Island Construction: **Strombolian/Hawaiian eruptions** from a **central vent** built the **cinder cone** (loose scoria, bombs, spatter). **Lava flows** (basaltic andesite) spilled from base, forming **Skell Channel** (submerged lava tube/flow) and **Wizard Island lava flow** (submerged, ~1.5 km²). **Final eruptions** created the **summit crater (90m wide, 20m deep)**. Activity ceased ~**7,200 years ago**.
- Lake Filling: **Precipitation/snowmelt** filled caldera over ~700 years (no inlet/outlet). Wizard Island emerged as an island.
Key Features
- Summit Crater: **~300 ft (90 m) diameter, ~60 ft (20 m) deep.** Accessible via trail.
- Composition: **Basaltic andesite** (53–57% SiO₂). **Cinders (scoria): vesicular, oxidized (red-brown).** Lava flows: **blocky, aa texture.**
- Vegetation: **Sparse.** **Whitebark pine (Pinus albicaulis), mountain hemlock, wildflowers (penstemon, lupine, paintbrush)** on wind-blown soil pockets. **No trees on summit cinders.**
- Klamath Name: **Llao** (kla-LAH) = "Rock" or "Chief of the Below World." **Llao Rock** (caldera rim) named for same deity. **Skell** = Chief of Above World. Myth: **Llao & Skell battle** = Mazama eruption.
Access & Experience
- Boat Tours (Summer only): **Crater Lake Hospitality** runs **Shuttle Boats** from **Cleatwood Cove** (1.1 mi hike down 700 ft / 213 m switchback trail). **3-hour stop on Wizard Island** (standard tour) or **6-hour (Wizard Island Summit Tour).**
- Hiking on Island:
- Wizard Island Summit Trail (2.2 mi RT, 760 ft gain): From dock → summit crater rim → **360° caldera views.** Strenuous.
- Fumarole Bay Trail (1.4 mi RT): Easy. Lakeshore, geothermal vents (cold).
- Swimming: **Allowed from boat dock** (only legal swimming in Crater Lake). **Water: 55–60°F (13–16°C).** Cold shock risk.
- Fishing: **Allowed (no license)** from shore/boat. **Kokanee salmon, Rainbow trout** (introduced 1888–1941).
- Camping: **Prohibited.** Day use only.
Scientific Value
- Natural Laboratory: **Closed basin, known age, simple hydrology.** Studies: **caldera formation, post-caldera volcanism, lake physics/chemistry/biology, climate record (sediment cores), hydrothermal systems.**
- Monitoring: **USGS Cascades Volcano Observatory.** Seismic, deformation, gas, lake temp/level. **Dormant, not extinct.**
Wizard Island is **geology exposed**—a **textbook cinder cone** in a **pristine caldera lake**, accessible for science and wonder alike.
Wanderlust World