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This paper explores paleoenvironmental and paleoecological information that may be obtained from small‐mammal assemblages recovered at central Alaska archaeological sites dated to the terminal Pleistocene and early Holocene (14,500–8,000 cal B.P.). Small‐mammal remains in these open‐air sites are primarily related to deposition by natural death causes and as such provide information on site paleoenvironments and landscape heterogeneity. Their presence within archaeological occupations likely relates to anthropogenic disturbance and features that would have favored burrow construction. The co‐occurrence of small‐mammal remains and archaeological occupations provides a chronological framework of presence in the locality for most recorded small‐mammal species. Small‐mammal remains document faunal turnover between Pleistocene and Holocene communities. The near‐contemporaneity of species that strongly differ in their ecological requirements suggest that the terminal Pleistocene and early Holocene in central Alaska was a period of dynamic change that may have been characterized by patchy vegetation distribution, rather than the climax communities seen today. In addition to the biogeographical value of small‐mammal remains the paleoenvironmental information that they provide help to characterize the ecology of early human settlers in the region and the processes behind human dispersal in Beringia and the Americas at the end of the Ice Age. [ABSTRACT FROM AUTHOR]

We present evidence of land‐level change resulting from the 2016 Mw 7.6 Chiloé earthquake from tidal wetlands along the southern coastline of Isla de Chiloé, Chile, to test criteria for the detection of low‐level, <0.1 m, coseismic land‐level change. In order to record coseismic land‐level change in tidal wetland sediments, both the creation and preservation thresholds must be exceeded. High‐resolution diatom analyses of sediment blocks at two tidal marshes reveal that the 2016 earthquake exceeded the creation threshold and a statistically significant change in diatom assemblage is recorded. In contrast, the preservation threshold was not exceeded and the record of coseismic land‐level motion is not preserved at any location visited. After nine months, interseismic and coseismic changes are statistically indistinguishable. The most sensitive part of the tidal wetland is not consistent between research locations, possibly as a result of changes in sedimentation after the earthquake. We compare records of change from great earthquakes in Alaska with the record from the Chiloé earthquake to explore the detection limit. We propose that coastal palaeoseismological records are highly likely to underestimate the frequency of major (Mw 7–8) earthquakes, with important implications for recurrence intervals and assessment of future seismic hazards. [ABSTRACT FROM AUTHOR]

The middle Tanana Valley of central Alaska contains a well‐preserved record of human occupation and paleoenvironmental change since the Late Glacial period (c. 16,000 cal yr BP) and is a critical region for understanding human dispersal into the Americas. Micromorphology analysis of soils and sediments from six archaeological sites yields valuable information about soil formation processes and landscape evolution during the Late Glacial and into the Holocene. At the macroscale, site stratigraphies are very similar, and thin organic‐rich layers (locally known as "stringers") are commonly interpreted as buried soils. However, at the microscale, these layers exhibit significant differences in the degree of bioturbation, organic matter humification, and boundary abruptness, indicating that pedogenesis was not the sole process at every site. In this way, our microscale analysis addresses issues of equifinality related to site formation interpretations, a persistent problem with subarctic and high‐latitude stratigraphy. Additionally, this study reveals a certain level of landform and landscape instability within a broader trend of regional increases in pedogenesis and vegetation coverage, adding to the existing model of heterogeneity across this subarctic landscape. Here we demonstrate the utility of micromorphology to test field interpretations and improve models of Late Glacial landscape evolution in high‐latitude contexts. [ABSTRACT FROM AUTHOR]

This study presents geomorphological, paleoenvironmental, and archaeological data from the upland upper Susitna River basin in the central Alaska Range. The goal of this study is to establish the landscape history and record of human use of the study area and test regional land‐use models. The results indicate that the upper Susitna was first occupied in the early Holocene at least 2,000 years after the end of full‐glacial conditions and 1,000 years after evidence of landscape recovery. Early Holocene land‐use consisted of short‐term task‐specific camps occupied by highly mobile groups on logistical forays. Upland land use intensified in the middle and late Holocene after modern vegetation patterns were established; during this time hunter‐gatherers occupied both residential and task‐specific camps in the study area in a logistical land‐use system. These results support a shift in land use in the early Holocene to include upland landscapes and intensification of upland landscape use in the late–middle Holocene. A shift in residential base camp location in the late Holocene may be tied to changing subsistence activities. There is evidence for a hiatus in human occupation following Holocene tephra fall, but it is unclear whether this was related to tephra deposition or broader climate instability. [ABSTRACT FROM AUTHOR]