Mummy Cave

Although it is referred to as a "cave", Mummy Cave is actually a broad, shallow alcove in a vertical cliff. It owes its depth to its overall size and the stability of the parent rock. The alcove's roof is about above the river, with the rock floor of the alcove at about above the river. By the time it was discovered, the alcove had been almost entirely filled with alluvium. The cliff is composed of Tertiary period volcanic ash mixed with larger rock fragments of volcanic origin. The cave fill has accumulated for at least 10,000 years and appears to have originated from nearby debris fans formed where weathered material has flowed down channels in neighboring cliffs. Apart from the depth and consistent nature of the alluvium, Mummy Cave is also characterized by extreme dryness. The pointed shape of the cliff above prevents rain and meltwater from percolating through the rock to the cave, and there are no vertical joints in the rock above. ==Archeological investigation==

The investigation of Mummy Cave was led by Robert Edgar from 1963 to 1965. The alcove was marked out into a grid, with a permanent reference mark for elevation marked on the wall. Initial investigation focused on establishing stratigraphy. Once the layers of alluvium in the cave floor were established, the excavation proceeded layer by layer. The excavations terraced the cave floor into levels, following the established reference grid. Digging was done with hand trowels in the artifact-bearing layers while layers devoid of artifacts were excavated with shovels. Spoils were disposed of down the embankment. The site had previously been disturbed by relic hunters, who had dug a deep pit in what turned out to be the most productive zone of the excavation. The relic hunters appear to have stopped when they encountered a rock cairn that covered what proved to be a human burial site. By the end of 1963 a portion of the site had been excavated to a depth of and shored with timbers, while the upper three cultural zones (layers 36–38) were removed across the site. During the 1964 season layers 29–35 were removed and some zones were excavated much more deeply. In 1965 layers 24–28 were removed from the central area of the alcove. By this time it was clear that excavation would proceed for the full depth of the site, and that the disposal of a considerable quantity of excavated debris would need to be addressed. A bulldozer was brought in to remove sections of fill beyond the drip line of the shelter. The 1966 season was directed by Wilfred M. Husted. Results of the Mummy Cave investigations were published in Science in 1968. ==Results==

The excavation of Mummy Cave yielded a nearly continuous succession of artifacts, which span a period of over 9000 years. The artifacts were disposed in a manner that permitted dating in both relative terms through stratigraphy, as well as through radiocarbon dating to establish an absolute scale. This continuum has proved to be invaluable in relating and dating other excavations in the Rocky Mountain region. In particular, the stone projectile points found at Mummy Cave have been used to set the standard for classifying stone arrowheads and spear heads in the region. This transition coincided with the climatic shift to the Altithermal. The wide range of artifacts discovered at the site has caused Mummy Cave to be seen as a highly significant site for the study of Rocky Mountain archeology. The cave's significance was recognized by the National Park Service with its placement on the National Register of Historic Places in 1981. == See also ==