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1. New Field Research at Galili, Afar State, Ethiopia

   Simpson, S.W. ; Quade, J. ; Said, H. ( January 2017 , American journal of physical anthropology)

   The paleoanthropological research potential of the sediments surrounding Mt. Galili in the Afar State of Ethiopia was first established by Y. Haile-Selassie in the late 1990s. Subsequently, a team led by H. Seidler conducted a series of field campaigns through 2010. Together, these projects discovered a number of valuable fossils, including hominins, that verified the importance of the area and provided a biochronological and geochronological framework for the sediments that span the ca. 2.5 Ma to >4.5 Ma period. Field research of the Mt. Galili Formation was reinitiated by our team in 2016. We conducted a short 13-day field survey of the area with the goals of collecting additional paleontological, geological, and archeological materials to better understand the biotic context during this period and provide additional age constraints on the deposits. Much of the survey focused on sediments on the middle Pliocene-aged Shabeley Laag Member with short surveys of the older Dhidinley and Lasdanan Mbrs. Altogether, a diverse array of terrestrial non-hominin (especially monkeys, suids, proboscideans, and bovids) and hominin fauna were collected. As noted by previous workers, the sediments are dominated by fluvial and lacustrine deposits with numerous intercalated air-fall tuffs and intrusive basalts. A number of geological specimens were collected and exported and await radiometric dating and tephrostratigraphic correlation analysis. Here, we will present preliminary results from the 2016 field survey. 

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2. A preliminary reconstruction of the paleoecological context of Galili, Ethiopia using bovid dental metrics.

   Slotter, A. ; Simpson, S.W. ( April 2018 , American journal of physical anthropology)

   Paleoanthropological and geological field research at Galili, Afar Regional State, Ethiopia was reinitiated in 2016. The site has been established as encompassing sediments ranging between 2.5-4.5± Ma and includes early Australopithecus and perhaps Ardipithecus . While preliminary paleoenvironmental analyses have suggested open woodland to bushland-wood - land and shrubland, we present here additional evidence of the diet and functional anatomy of the Early Pliocene bovids from Galili. Fossil bovids have been recognized as a crucial tool in understanding ancient environments and serve as an important ecological indicator. Establishing the habitats of Galili is important for both understanding the environment in which the fauna, including hominins, resided and providing comparison to other contemporaneous sites. Taxonomic identification and metric analyses were performed on bovid teeth (n=93) from the 3.9-4.4 Ma Shabeley Laag and Dhidinley members to reconstruct the paleoenvironment. The sample was dominated by Reduncini, a riparian-associated tribe, and Tragelaphini, a browsing-associated tribe. Hypsodonty index was calculated for each tribe and results suggest the most abundant bovid taxa trend towards the brachydont category. Only three tribes: Alcelaphini, Antilopini, and Hippotragini fell within the mesodont category, and no tribes had hypso - dont indices. Mesowear analysis of the sample indicated high occlusal relief and rounded cusp shapes were most common. Taken together, our results indicate a trend in bovid diet towards mixed feeding and browsing at Galili. We thank Prof. H Seidler and his team for allowing access to the fossils they collected. 

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3. A preliminary reconstruction of the paleoecological context of Galili, Ethiopia using bovid dental metrics

   Slotter, A. ; Simpson, S. W. ( January 2018 , American journal of physical anthropology)

   Paleoanthropological and geological field research at Galili, Afar Regional State, Ethiopia was reinitiated in 2016. The site has been established as encompassing sediments ranging between 2.5-4.5± Ma and includes early Australopithecus and perhaps Ardipithecus. While preliminary paleoenvironmental analyses have suggested open woodland to bushland-woodland and shrubland, we present here additional evidence of the diet and functional anatomy of the Early Pliocene bovids from Galili. Fossil bovids have been recognized as a crucial tool in understanding ancient environments and serve as an important ecological indicator. Establishing the habitats of Galili is important for both understanding the environment in which the fauna, including hominins, resided and providing comparison to other contemporaneous sites. Taxonomic identification and metric analyses were performed on bovid teeth (n=93) from the 3.9-4.4 Ma Shabeley Laag and Dhidinley members to reconstruct the paleoenvironment. The sample was dominated by Reduncini, a riparian-associated tribe, and Tragelaphini, a browsing-associated tribe. Hypsodonty index was calculated for each tribe and results suggest the most abundant bovid taxa trend towards the brachydont category. Only three tribes: Alcelaphini, Antilopini, and Hippotragini fell within the mesodont category, and no tribes had hypsodont indices. Mesowear analysis of the sample indicated high occlusal relief and rounded cusp shapes were most common. Taken together, our results indicate a trend in bovid diet towards mixed feeding and browsing at Galili. 

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4. A preliminary reconstruction of the paleocological context of Galili, Ethiopia using bovid dental metrics.

   Slotter, A. ; Simpson, S. W. ( January 2018 , American journal of physical anthropology)

   Paleoanthropological and geological field research at Galili, Afar Regional State, Ethiopia was reinitiated in 2016. The site has been established as encompassing sediments ranging between 2.5-4.5± Ma and includes early Australopithecus and perhaps Ardipithecus. While preliminary paleoenvironmental analyses have suggested open woodland to bushland-woodland and shrubland, we present here additional evidence of the diet and functional anatomy of the Early Pliocene bovids from Galili. Fossil bovids have been recognized as a crucial tool in understanding ancient environments and serve as an important ecological indicator. Establishing the habitats of Galili is important for both understanding the environment in which the fauna, including hominins, resided and providing comparison to other contemporaneous sites. Taxonomic identification and metric analyses were performed on bovid teeth (n=93) from the 3.9-4.4 Ma Shabeley Laag and Dhidinley members to reconstruct the paleoenvironment. The sample was dominated by Reduncini, a riparian-associated tribe, and Tragelaphini, a browsing-associated tribe. Hypsodonty index was calculated for each tribe and results suggest the most abundant bovid taxa trend towards the brachydont category. Only three tribes: Alcelaphini, Antilopini, and Hippotragini fell within the mesodont category, and no tribes had hypsodont indices. Mesowear analysis of the sample indicated high occlusal relief and rounded cusp shapes were most common. Taken together, our results indicate a trend in bovid diet towards mixed feeding and browsing at Galili. 

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5. QUANTIFYING LANDSCAPE CHANGE AT VERMONT’S LARGEST LANDSLIDE USING TIME-LAPSE SPATIAL DIFFERENCING OF 3D SURFACE MODELS FROM DRONE AND FIELD SURVEY DATA, WATERBURY, VERMONT

   https://doi.org/10.1130/abs/2023SE-385477  

   Klepeis, Keith ; Kim, Jonathan ; Juozelskis, Siga ; Springston, George ; Myrick, Emma ( March 2023 , Geological Society of America Abstracts with Programs)

   On May 31, 2019, a landslide near Waterbury in central Vermont removed >200,000 m3 of glacial lake deposits from a hillside in the Mt. Mansfield State Forest and transported the material across Cotton Brook, creating a dam near its toe. In the months following the slide, the brook breached the toe, removing ≥54, 000 m3 of sediment and transporting it ~1.3 km downstream into the Waterbury reservoir where it formed a large sedimentary delta. The delta grew 243% by Fall, 2020 until it began to erode into the reservoir in 2021. A collaborative team from the Vermont Geological Survey, the Vermont Agency of Transportation, Norwich University, and the University of Vermont team began a yearly monitoring of these events in 2019 using field-based mapping of bedrock and surficial geology, photogrammetry using annual drone surveys, and two LiDAR data sets. The first LiDAR data set was collected in 2014 prior to the slide by the Vermont Center for Geographic Information and the second after the slide in 2021 by the U.S. Army Corp of Engineers. Time-lapse spatial differencing allowed us to (1) quantify changes in surface topography over time, (2) calculate sediment budgets from source (landslide) to sink (delta), and (3) determine how mechanisms of mass wasting changed over time. Through this study we have also documented the following: (a) a second slip event in 2020 that removed ~25, 000 m3 of additional material from the hillside and contributed to growth of the Waterbury reservoir delta, (b) bedrock basins defined by the intersection of bedrock foliation and orthogonal fracture sets that appear to control slip location and geometry, (c) bedrock structures that influence the subsurface hydrology of the slip, which is expressed by oxidized groundwater seeps and a preferential deepening of rills into gullies on one side, and (d) how horizontal variations in the type and thickness of glacial lake sediments influenced mass-wasting mechanisms, including catastrophic failure of the hillside, the slumping of landslide sidewalls, the formation of crescent-shaped earth fractures, channeling around slumps, and the removal of material in deepening gullies. This study shows how a large landslide evolves from a major failure phase through later erosional and colluvial adjustments and supplies sediment at an episodic rate to the surface water system. 

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