Human Occupation at the Lake
When did humans first arrive at the lake, either the ancient lake or modern day Lake Minchumina to utilize its resources is one of the main questions to be addressed with this study. Those lands within Denali National Park and Preserve and the immediate region have a high potential for archaeological resources as demonstrated by the well known late Pleistocene/early Holocene sites at Dry Creek (Powers et al. 1983), Carlo Creek (Bowers 1978, 1980), Bull River II (Wygal 2009), and now Teklanika West (Coffman and Potter 2011). This project is designed to identify, map, and radiocarbon date geomorphic features associated with ancestral Lake Minchumina Denali National Park Alaska
Understanding the geomorphology of the area will be vital to locating and assess archaeological resources associated with the ancient lake. Identify landforms on the landscape that would have provided optimal landuse to prehistoric hunter-gatherers will be selected and investigated. Sampling ancient beaches from both an archaeological and geological perspective will also provide insight into understanding the landscape and landuse patterns among hunter-gatherers. Future research would need to be performed at individual sites to understand more site-specific questions.
Understanding how and when the ancient lake formed and conversely, how and when it began to drain is an important question for this project, but also important to understanding the natural history of the area as well. Understanding the formation and draining properties interlinks with the human objectives. There is a distinct possibility that the lake may have already been drained by the late Pleistocene/early Holocene and humans never laid sight on the ancient lake and avoided the area all together. Therefore, dating the different beach ridges will be key in understanding the age of the lake, but also assist in locating beaches/landforms that may have archaeological sites associated with them. Dating these beaches will in effect be developing a chronology for the lake. Once this chronology for the lake has been developed, beach ridges may be used as an alternative to dating the retreat of the lake and human occupation of the lake. By understanding where and on what beach an archaeological site lies on, we may be able to better gauge the age of these archaeological sites in addition to incorporating both radiometric and artifact typology.
In addition to dating the age of the lake, considerable attention will be given to understanding how and why the lake formed and subsequently drained. One current hypothesis is that sand dunes either at the north or south or at both ends of lake acted as a natural damming agent ultimately forming the lake. Consequently, what were the agents that prompted the lake to drain? Geomorphology work will address these objectives.
In determining the formation of the lake, mapping the geomorphological features associated with the lake will be important. Mapping and sampling the ancient beaches of the lake will act as a means to understand the recession and sediment matrix of these beaches. Analyzing these sediments will assist in identify the origin and composition of these (i.e. beach gravels, loess deposits, glacial outwash etc…) sediments and their dispositional histories.
Lastly, in looking at the sediment composition, diatom analyses will also be used to assist in understanding the past climate, the ancient lake’s extent, and possibly the draining event of the lake. Diatoms are both an effective proxy for climate change due to their sensitivity to a variety of ecological conditions and have been used to indicate past flooding events (Wiklund et al. 2010). Past changes in climate can be inferred from changes in species abundance within a sediment core, as the ecological requirements are well known for a number of ‘indicator’ species. These species are indicative of several variables, including lake level and nutrient availability. These variables are dependent upon a combination of primary factors (including precipitation, solar output, and wind strength) and secondary factors (including upwelling and erosion).
