About Esker Associates, LLC
Esker Associates, LLC (Esker) is a consulting firm that helps its clients solve pressing environmental and water resources problems. Esker was established as a consulting firm in 2022 by principal scientist Adam N. Johnson.
Adam received a B.A. in geology from Macalester College and a M.S. in hydrogeology from the University of Montana. He has about 20 years of diversified professional experience as a hydrogeologist and environmental scientist. As a consulting scientist since 2006, Adam specializes in assessment and remediation of contaminated properties, Brownfields sites, and water resources projects. He works frequently with American Indian and Alaska Native organizations and tribal consortia on a variety of projects.
Adam has worked in the mining, energy, government, industrial-commercial, oil and gas, and water resources sectors. Geographic areas of experience include Mexico, South America, and most of the western United States. He has authored or co-authored peer-reviewed journal articles, government documents, and numerous technical reports.
Prior to consulting, he worked for several federal agencies, including the U.S. Geological Survey, the National Park Service, and the U.S. Forest Service.
What Is An Esker?
Eskers are elongated serpentine ridges of sediment that represent beds of meltwater stream channels that flowed through ice tunnels within or beneath glaciers. The streams carried and accumulated large volumes of sand and gravel and deposited their loads as horizontal layers. When the glaciers eventually retreated, the sediment support systems were removed and the layers collapsed. Most eskers are narrow with rounded crests, and their steep sides are consistent with the collapse of sedimentary layers. Eskers can be up to several miles in length and rise more than 100 feet above the surrounding terrain. In general, their compass orientations reflect the direction of flow of the former parent glaciers. Chevron symbols are used to denote their presence on geologic maps.
Source: Federal Geographic Data Committee – Digital Cartographic Standard for Geologic Map Symbolization
Esker extending into Salmon Lake, Seeley-Swan Valley, Montana. The lake is visible on both sides of the image.