Missoula floods
E95487
The Missoula floods were a series of cataclysmic Ice Age glacial outburst floods that repeatedly swept across the Pacific Northwest, dramatically reshaping the landscape of what is now Washington, Oregon, Idaho, and Montana.
All labels observed (7)
| Label | Occurrences |
|---|---|
| Missoula Floods | 5 |
| Spokane Floods | 2 |
| Bretz floods | 1 |
| Ice Age floods | 1 |
| Missoula Flood | 1 |
| Missoula floods canonical | 1 |
| catastrophic Pleistocene flooding (Bonneville Flood) | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T802029 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Missoula floods Context triple: [Columbia Plateau, erodedBy, Missoula floods]
-
A.
Peshtigo Fire
The Peshtigo Fire was a catastrophic 1871 forest fire in Wisconsin that remains the deadliest wildfire in United States history.
-
B.
Avalanche
Avalanche is the codename for Operation Avalanche, the Allied invasion of mainland Italy during World War II that began with the Salerno landings in September 1943.
-
C.
Black Saturday
Black Saturday is the Christian observance between Good Friday and Easter Sunday that commemorates Jesus Christ’s body lying in the tomb and his followers’ mourning and waiting.
-
D.
Nevada Fall
Nevada Fall is a prominent and picturesque waterfall on the Merced River in Yosemite National Park, known for its powerful drop and dramatic granite surroundings.
-
E.
Great Midwest Fires of 1871
The Great Midwest Fires of 1871 were a series of devastating wildfires across several Midwestern U.S. states, including the infamous Peshtigo Fire, that caused massive destruction and loss of life in early October 1871.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Missoula floods Target entity description: The Missoula floods were a series of cataclysmic Ice Age glacial outburst floods that repeatedly swept across the Pacific Northwest, dramatically reshaping the landscape of what is now Washington, Oregon, Idaho, and Montana.
-
A.
Peshtigo Fire
The Peshtigo Fire was a catastrophic 1871 forest fire in Wisconsin that remains the deadliest wildfire in United States history.
-
B.
Avalanche
Avalanche is the codename for Operation Avalanche, the Allied invasion of mainland Italy during World War II that began with the Salerno landings in September 1943.
-
C.
Black Saturday
Black Saturday is the Christian observance between Good Friday and Easter Sunday that commemorates Jesus Christ’s body lying in the tomb and his followers’ mourning and waiting.
-
D.
Nevada Fall
Nevada Fall is a prominent and picturesque waterfall on the Merced River in Yosemite National Park, known for its powerful drop and dramatic granite surroundings.
-
E.
Great Midwest Fires of 1871
The Great Midwest Fires of 1871 were a series of devastating wildfires across several Midwestern U.S. states, including the infamous Peshtigo Fire, that caused massive destruction and loss of life in early October 1871.
- F. None of above. chosen
Statements (50)
| Predicate | Object |
|---|---|
| instanceOf |
cataclysmic flood event
ⓘ
glacial lake outburst flood ⓘ paleoflood ⓘ |
| alsoKnownAs |
Missoula floods
ⓘ
surface form:
Bretz floods
Missoula floods ⓘ
surface form:
Missoula Flood
Missoula floods ⓘ
surface form:
Spokane Floods
|
| associatedWith |
Cordilleran Ice Sheet
ⓘ
Glacial Lake Columbia ⓘ Lake Lewis ⓘ |
| cause |
failure of the ice dam of Glacial Lake Missoula
ⓘ
repeated ice-dam collapses on the Clark Fork River ⓘ |
| created |
coulees
ⓘ
dry falls ⓘ giant current ripples ⓘ hanging valleys ⓘ large gravel bars ⓘ pothole cataracts ⓘ |
| deposited |
erratic boulders transported on icebergs
ⓘ
thick layers of silt in the Willamette Valley ⓘ |
| endTime | approximately 13,000 years ago ⓘ |
| evidenceFoundIn |
Columbia River Gorge National Scenic Area
ⓘ
surface form:
Columbia River Gorge
eastern Washington ⓘ northern Idaho ⓘ western Montana ⓘ |
| hasOrigin |
Clark Fork River and Bitterroot River
ⓘ
surface form:
Clark Fork River valley
Lake Missoula basin ⓘ
surface form:
Glacial Lake Missoula
|
| influenced |
regional drainage patterns of the Columbia River system
ⓘ
soil distribution in eastern Washington and Oregon ⓘ |
| maximumDischarge | on the order of 10 million cubic meters per second ⓘ |
| maximumLakeDepth | over 600 meters at the ice dam ⓘ |
| maximumLakeVolume | approximately 2,100 cubic kilometers ⓘ |
| partOf |
Cenozoic glaciations
ⓘ
surface form:
Quaternary glacial history of North America
|
| recognizedAs | one of the largest known freshwater floods on Earth ⓘ |
| recurrence |
dozens of separate flood events
ⓘ
possibly more than 40 major floods ⓘ |
| reshaped |
Channeled Scablands
ⓘ
Columbia River Gorge National Scenic Area ⓘ
surface form:
Columbia River Gorge
Snake River Plain features ⓘ Spokane River ⓘ
surface form:
Spokane River valley
Willamette Valley ⓘ |
| startTime | approximately 18,000 years ago ⓘ |
| studiedBy | J Harlen Bretz ⓘ |
| timePeriod |
Wisconsin glaciation
ⓘ
surface form:
Late Wisconsin glaciation
Pleistocene epoch ⓘ |
| tookPlaceIn |
Idaho
ⓘ
Montana ⓘ Oregon ⓘ Pacific Northwest ⓘ United States of America ⓘ
surface form:
United States
Washington ⓘ
surface form:
Washington (state)
|
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Missoula floods Description of subject: The Missoula floods were a series of cataclysmic Ice Age glacial outburst floods that repeatedly swept across the Pacific Northwest, dramatically reshaping the landscape of what is now Washington, Oregon, Idaho, and Montana.
Referenced by (12)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Missoula Floods
this entity surface form:
Missoula Flood
this entity surface form:
Spokane Floods
this entity surface form:
Bretz floods
this entity surface form:
Missoula Floods
this entity surface form:
Ice Age floods
this entity surface form:
Spokane Floods
this entity surface form:
catastrophic Pleistocene flooding (Bonneville Flood)
this entity surface form:
Missoula Floods
this entity surface form:
Missoula Floods
this entity surface form:
Missoula Floods