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Brandon L. Graham

Publications and source records attributed to Brandon L. Graham.

5 recordsLinked to original sources
USGS2026

Hydrogeology and water quality of the unconsolidated aquifer system in the lower Fall Creek valley, Tompkins County, New York

The U.S. Geological Survey, in cooperation with Tompkins County and the Town of Dryden, conducted a hydrogeologic investigation of the lower Fall Creek unconsolidated aquifer system in Tompkins County, New York. This study is part of an ongoing effort to characterize major valley-fill aquifers in the region to support sustainable groundwater management. The lower Fall Creek valley, encompassing the Village of Freeville, the unincorporated communities of Etna, and the hamlets of McLean and Varna, has experienced moderate development and relies heavily on groundwater for residential, agricultural, and commercial use. The study area spans approximately 51 square miles along the boundary of the Allegheny Plateau and North Rim of the Allegheny Plateau physiographic provinces. The aquifer system, composed primarily of glacially derived sand and gravel deposits, includes both unconfined and confined aquifer units. For the approximately 2,300 people who live over the aquifers, groundwater is the sole source of drinking water. In some areas, such as the Village of Freeville, artesian conditions exist, with potentiometric heads exceeding 25 feet above land surface. This report describes the hydrogeologic framework, aquifer distribution, groundwater-flow dynamics, and water quality of the lower Fall Creek aquifer system. Groundwater is generally hard and contains elevated concentrations of redox-sensitive constituents, such as iron and manganese relative to U.S. Environmental Protection Agency secondary maximum contaminant levels. Arsenic was not detected above the U.S. Environmental Protection Agency maximum contaminant level during this study but remains a regional concern due to past detections in the study area and nearby aquifers. The findings provide data for local planners and resource managers to use in understanding and protecting this water resource.

New York↗
USGS2026

Hydrogeology and water quality of the unconsolidated aquifer system in the Lower Fall Creek Valley, Tompkins County, New York

The U.S. Geological Survey, in cooperation with Tompkins County and the Town of Dryden, conducted a hydrogeologic investigation of the lower Fall Creek unconsolidated aquifer system in Tompkins County, New York. This study is part of an ongoing effort to characterize major valley-fill aquifers in the region to support sustainable groundwater management. The lower Fall Creek valley, encompassing the Village of Freeville, the unincorporated communities of Etna, and the hamlets of McLean and Varna, has experienced moderate development and relies heavily on groundwater for residential, agricultural, and commercial use. The study area spans approximately 51 square miles along the boundary of the Allegheny Plateau and North Rim of the Allegheny Plateau physiographic provinces. The aquifer system, composed primarily of glacially derived sand and gravel deposits, includes both unconfined and confined aquifer units. For the approximately 2,300 people who live over the aquifers, groundwater is the sole source of drinking water. In some areas, such as the Village of Freeville, artesian conditions exist, with potentiometric heads exceeding 25 feet above land surface. This report describes the hydrogeologic framework, aquifer distribution, groundwater-flow dynamics, and water quality of the lower Fall Creek aquifer system. Groundwater is generally hard and contains elevated concentrations of redox-sensitive constituents, such as iron and manganese relative to U.S. Environmental Protection Agency secondary maximum contaminant levels. Arsenic was not detected above the U.S. Environmental Protection Agency maximum contaminant level during this study but remains a regional concern due to past detections in the study area and nearby aquifers. The findings provide data for local planners and resource managers to use in understanding and protecting this water resource.

EarthArXiv↗
USGS2026

The Great Lakes Geologic Mapping Coalition—Working collaboratively to understand the geology of the Great Lakes Region

Introduction The Great Lakes Geologic Mapping Coalition (GLGMC), commonly referred to as the “Coalition,” is a partnership between the U.S. Geological Survey (USGS), the U.S. States of Illinois, Indiana, Michigan, Minnesota, New York, Ohio, Pennsylvania, and Wisconsin and the Canadian province of Ontario. The member States receive funding for geologic mapping work from the USGS National Cooperative Geologic Mapping Program (NCGMP), whereas Ontario participates as a nonfunded partner. The mission of the GLGMC is to produce three-dimensional (3D) geologic maps that depict unconsolidated sediments and near-surface bedrock in the Great Lakes region of North America. Geologic maps are the basis of most earth science investigations and help support resource exploration (energy, minerals, groundwater), natural hazard mitigation, infrastructure development, and land-use planning, all of which can be used to advance economic development and strengthen national security in the Great Lakes region. During the last few million years, the Great Lakes region has experienced repeated glacial advances and retreats, leaving behind extensive sediments, abundant natural resources, and widespread effects on the underlying bedrock geology (Swezey and others, 2022). Linked by shared histories of past glaciations, industrial agriculture, and legacy automotive, coal, steel, and manufacturing industries, the GLGMC member States collaborate to improve the understanding of the 3D distribution of the sediments overlying the region’s bedrock (fig. 1). Developing a comprehensive subsurface 3D framework of this glaciated terrain can provide earth science data to policymakers at all levels. These insights facilitate informed decisions on the exploration, use, and protection of vital resources, such as critical minerals, industrial materials, and aquifers, thereby supporting economic prosperity and the well-being of the citizens of this region. Since its inception in 1998, the Coalition has completed more than 100 geologic mapping projects across the Great Lakes region. Each project aims to deliver geologic maps, 3D datasets, and other information that improves understanding of the geology of the Great Lakes region, with an emphasis on economic and water resources. Key deliverables include 3D geologic maps and models typically portraying sediment thickness, often derived from top-of-bedrock and borehole data. These products are developed through a combination of fieldwork, subsurface modeling, and the collection and analysis of rock and sediment cores. To support Coalition goals, member States collaborate with scientists working on related STATEMAP, EDMAP, and FEDMAP projects. Coalition scientists also engage with Tribal Nations in the Great Lakes region to ensure that Tribal interests pertaining to Coalition work are addressed. Through this collaboration, the Coalition unites the efforts of State, Federal, and Tribal Nation stakeholders to advance geologic data production and enhance understanding of the geologic resources of the Great Lakes region.

Illinois, Indiana, Michigan, Minnesota, New York, ↗
USGS2025

East Greenland Ice Sheet retreat history from Scoresby Sund and Storstrømmen Glacier during the last deglaciation

The lack of geological constraints on past ice-sheet change in marine-based sectors of the Greenland Ice Sheet (GrIS) following the Last Glacial Maximum limits our ability to assess (1) the drivers of ice-sheet change, and (2) the performance of ice-sheet models that are benchmarked against the paleo-record of GrIS change. Here, we provide new in situ 10 Be surface exposure chronologies of ice-sheet margin retreat from the outer Scoresby Sund and Storstrømmen Glacier regions in eastern and northeastern Greenland, respectively. Ice retreated from Rathbone Island, east of Scoresby Sund, by ∼ 14.1 ka, recording some of the earliest documentations of terrestrial deglaciation in Greenland. The mouth of Scoresby Sund deglaciated by ∼ 13.2 ka, and retreated at an average rate of ∼ 43 m yr −1 between 13.2 and 9.7 ka. Storstrømmen Glacier retreated from the outer coast to within ∼ 3 km of the modern ice margin between ∼ 12.7 and 8.6 ka at an average rate of ∼ 28 m yr −1 . Retreat then slowed or reached a stillstand as ice retreated ∼ 3 km between ∼ 8.6 ka to the modern ice margin at ∼ 8.0 ka. These retreat rates are consistent with late glacial and Holocene estimates for marine-terminating outlet glaciers across East Greenland, and comparable to modern retreat rates observed at the largest ice streams in northeastern, and northwestern Greenland.

Scoresby Sund, Storstrømmen Glacier↗