Massacre Rocks
Basic information
Sample name: Massacre Rocks
Sample aka: IMNH 85002
Reference: H. G. McDonald. 1998. The Massacre Rocks local fauna from the Pleistocene of southeastern Idaho. Idaho Museum of Natural History Occasional Paper 36:156-172 [ER 4183]
Geography
Country: United States
State: Idaho
County: Power
Coordinate: 42.68° N, -112.97° W
Latlng basis: stated in text
Scale: quarry
Time interval: Late Pleistocene
Zone: Rancholabrean
Max Ma: 0.126
Min Ma: 0.072
Age basis: OSL
Geography comments: "Sec. 32 T8S, R30E" at an elevation of "approximately 1311.5 m"
thought to be Rancholabrean and roughly equivalent in age to the Late Pleistocene American Falls fauna, providing an upper age limit of 0.126 Ma
underlies the Cedar Butte Basalt, "which is potassium-argon dated to 72, 000 ± 14, 000 years B.P."
thought to be Rancholabrean and roughly equivalent in age to the Late Pleistocene American Falls fauna, providing an upper age limit of 0.126 Ma
underlies the Cedar Butte Basalt, "which is potassium-argon dated to 72, 000 ± 14, 000 years B.P."
Environment
Lithology: conglomerate
Taphonomic context: fluvial deposit
Habitat comments: a "paleochannel" represented by "unconsolidated... bedded gravel deposits... secondary features such as subaqueous dunes were exposed in the back wall of the trench" and "water depth was about 1 m"
Methods
Life forms: carnivores, ungulates, other large mammals
Sampling methods: quarry
Sample size: 141 specimens
Years: 1985
Days: 3
Museum: Idaho Museum of Natural History
Net or trap nights: 0
Basal area status: not applicable
Sampling comments: "found during construction of Interstate 86" and a "test trench" was excavated "from 28 February to 2 March, 1985"
fragments of "shell" were also found
fragments of "shell" were also found
Metadata
Sample no: 4647
Contributor no: John Alroy
Enterer: John Alroy
Created: 2025-01-09 05:04:10
Modified: 2025-01-09 05:04:10
Abundance distribution
Each square represents a species. Square sizes are proportional to counts. Values are logged.
Statistics
11 species
4 singletons
total count 141
geometric series index: 22.7
Fisher's α: 2.79
geometric series k: 0.6539
Hurlbert's PIE: 0.6839
Shannon's H: 1.4914
Good's u: 0.9719
Register
| †Megalonyx jeffersonii (Jefferson's ground sloth) | 2 | |
| †Paramylodon harlani (ground sloth) | 2 | |
| plus 2 Xenartha indet. | ||
| Canis latrans (coyote) | 1 | 12.0 kg |
| †Smilodon fatalis (saber-toothed cat) | 1 | |
| Mammuthus sp. | 1 | |
| cf. | ||
| †Mammut cf. americanum (American mastodon) | 1 | |
| plus 9 Proboscidea indet. | ||
| Equus sp. | 23 | |
| †Camelops hesternus (camel) | 70 | |
| Odocoileus sp. | 2 | |
| †Bison latifrons (bison) | 25 | |
| †Bison cf. antiquus (bison) | 13 | |
| plus 7 Bison sp. | ||