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Flowing wells and municipal water supplies in the southern portion of the southern peninsula of Michigan

A large amount of data on water supplies was collected by the writer in the course of glacial investigations made under the direction of Prof. T. C. Chamberlin in the last five years in the Southern Peninsula of Michigan. These investigations resulted in a partial acquaintance with conditions in about 200 separate flowing-well districts and brought out matters of such exceptional importance that arrangements were made to extend them by examining each of the flowing-well districts in the State sufficiently to determine its essential characteristics, present state of development, and probable capacity for future development. It was arranged also that the quality of various classes of waters, both surface and underground, as well as water supplies of the cities and villages, should be given attention. As the mineral waters of the State had already been discussed in some detail by the State geologist, Dr. A. C. Lane, in Water-Supply Paper No. 31 of the United States Geological Survey, it was deemed unnecessary to prepare another report on that subject, but arrangements were made with Doctor Lane for embodying in this report the large amount of material which had accumulated at his office relative to other classes of water supply, and also for furnishing reports on certain counties in which special investigations had been carried on by the State survey. The results of all these studies, so far as they apply to the southern counties (see fig. 1), are embodied in the present report; the remainder will appear in a companion report on the middle and northern counties of the Southern Peninsula of Michigan.

Michigan

Flowing wells and municipal water supplies in the middle and northern portions of the southern peninsula of Michigan

A large amount of data on water supplies was collected by the writer in the course of glacial investigations made under the direction of Prof. T. C. Chamberlin in the last five years in the Southern Peninsula of Michigan. These investigations resulted in a partial acquaintance with conditions in about 200 separate flowing-well districts and brought out matters of such exceptional importance that arrangements were made to extend them by examining each of the flowing-well districts in the State sufficiently to determine its essential characteristics, present state of development, and probable capacity for future development. It was arranged also that the quality of various classes of water, both surface and underground, as well as water supplies of, cities and villages, should be given attention. As the mineral waters of the State had already been discussed in some detail by the State geologist, Dr. A. C. Lane, in Water-Supply Paper No. 31 of the United States Geological Survey, it was deemed unnecessary to prepare another report on that subject, but arrangements were made with Doctor Lane for embodying in this report the large amount of material which had accumulated at his office relative to other classes of water supply, and also for furnishing reports on certain counties in which special investigations had been carried on by the State survey. The results of all these studies, so far as they apply to the middle- and northern counties (see fig. 1, on next page), are embodied in the present report; the remainder appears in a companion report on the southern counties of the Southern Peninsula of Michigan.

Michigan

Land use statistics for West Virginia, Part I

The West Virginia Geological and Economic Survey and the United States Geological Survey have completed a cooperative program to provide land-use and land-cover maps and data for the State. This program begins to satisfy a longstanding need for a consistent level of detail, standardization in categorization, and scale of compilation for land-use and land-cover maps and data. The statistical information contained in this Bulletin provides land-use acreage tabulations for the first 20 counties that have been completed. Statistics are being compiled for the remaining counties and will be published shortly. This information has been derived from the recently completed Land-Use Map of West Virginia (on open file at the West Virginia Geological and Economic Survey - Environmental Section). In addition to land-use acreage, we have also included land-use percent. All statistics throughout this Bulletin are in the same format for ease of comparison.

West Virginia

Report of committee on glaciers, April 1939

The Committee on Glaciers at present is constituted as follows: Harry Fielding Reid—Professor‐Emeritus of Geology, Johns Hopkins University (former member of the International Glacier Commission), 608 Cathedral Street, Baltimore, Maryland William H. Hobbs—Professor‐Emeritus of Geology, University of Michigan (until recently Vice‐ President of the International Glacier Commission, at present associate member), Ann Arbor, Michigan J. E. Church—Professor of Classics, University of Nevada (President of the International Commission of Snow, and Chairman of the Committee on Snow of the Section of Hydrology, American Geophysical Union), Reno, Nevada Colonel Lawrence Martin—Chief of the Division of Maps, Library of Congress, Washington, D. C. Wm. Osgood Field, Jr.—Explorer, 18 West Twelfth Street, New York, N.Y. Earl A. Trager—Chief of the Naturalist Division, National Park Service, Washington, D. C. Glenn L. Parker—District Engineer, Water Resources Branch, United States Geological Survey, 406 Federal Building, Tacoma, Washington Oliver Kehrlein—Chairman, Committee on Glacier Studies, Sierra Club, 1050 Mills Tower, San Francisco, California Kenneth N. Phillips—Associate Hydraulic Engineer, Water Resources Branch, United States Geological Survey, Chairman, Research Committee of the Mazamas, 606 Post‐Office Building, Portland, Oregon William S. Cooper—Professor of Botany, University of Minnesota, Minneapolis, Minnesota Gerald FitzGerald, Senior Topographic Engineer, Alaska Branch, United States Geological Survey, Washington, D.C. Laurence M. Gould, Professor of Geology, Carleton College, Northfield, Minnesota François E. Matthes, Chairman , Senior Geologist, Section of Glacial Geology, United States Geological Survey (titular member of the International Glacier Commission), Washington, D.C. In 1938, as in previous years, the Committee devoted its energies primarily to the collecting of data on the variations in length and volume of American glaciers, it being felt that the maintenance of a continuous record of these variations is of prime importance, not only to hydrology and glaciology, but, as has become increasingly evident recently, also to climatology, geomorphology, geography, ecology, history, and archaeology. As the time available for the work of the Committee is limited and does not permit covering the entire field of glaciology, it seems best to devote it before all else to this line of research which yields results of value to so many different sciences. Besides, the gathering of data on glacier‐oscillations is not a one‐man job that can be taken up or dropped at convenience from time to time, but is an organized and far‐flung enterprise whose success depends upon the faithful cooperation of many volunteer workers located in different parts of the country. Such an enterprise, once launched, must be kept running or it will disintegrate and the precious enthusiasm of the field‐workers will be lost.

Eos, Transactions, American Geophysical Union

Ground-water investigations in Utah in 1960 and ground-water reports published by the U.S. Geological Survey or the Utah State Engineer prior to 1960

Listed below and shown on the map are projects in the ground-water program being conducted cooperatively by the U.S. Geological Survey and the Utah State Engineer. Project UT-5 is conducted from a field office in Cedar City, project UT-17 from a field office in Richfield, project UT-26 from a field office in Fillmore, and all other projects are operated from the Geological Survey offices in Salt Lake City.

Utah

Investigations of the fluctuations of the ground‐water table in Pennsylvania

Hydraulic engineers are interested in ground ‐ water as a source of water supply and also as it affects stream‐flow. The stream‐flow is especially valuable at low stages and it is at the low stages that it is most closely related to the ground ‐ water conditions. For several years the Pennsylvania Topographic and Geologic Survey and the United States Geological Survey have cooperated in making a comprehensive study of the ground ‐ water resources of Pennsylvania , but no adequate records of ground ‐ water levels have in the past been obtained. Recently, however, a project for obtaining systematic records in Pennsylvania has been started. ©1932. American Geophysical Union.

Pennsylvania

Crustal thickness and the VP/VS ratio within the Arabia Plate from P-wave receiver functions at 154 broadband seismic stations

As part of a joint Saudi Geological Survey (SGS) and United States Geological Survey project, we analyzed P-wave receiver functions from seismic stations covering most of the Kingdom of Saudi Arabia to map the thickness of the crust across the Arabia Plate. We present an update of crustal thickness estimates and fill in gaps for the western Arabian Shield and the rifted margin at the Red Sea (the coastal plain), as well as the eastern Arabian Platform. We applied a conventional H-k stacking algorithm and included careful attention to stacking weights, two forms of sedimentary corrections for stations located on the Arabian Platform, and additional processing for noisy stations. We obtained useful results at 154 stations from 898 teleseismic events over a 2-year period from 1995–1997 (for non-SGS stations) and a 6-year period from 2008–2014 (for SGS stations). Average crustal thickness (that is, depth to the Mohorovičić discontinuity [Moho] below the surface) beneath the Red Sea coastal plain (the rift margin) is 29 kilometers (km), beneath the volcanic fields (known in Arabic as harra [plural] or harrat [singular]) is 35 km, beneath the Arabian Shield (excluding harrats) is 37 km, and beneath the Arabian Platform is 38 km. Crustal thinning appears not to extend east of the rift escarpment, suggesting uniform extension that is no broader at depth than at the surface. In contrast to some previous interpretations that the Arabian Platform crust is thicker than that of the Arabian Shield, we find no statistically significant difference between their whole crustal thicknesses. However, the average sub-sedimentary crustal thickness (that is, the crystalline crust) for stations on the Arabian Platform is 34 km, 3 km thinner than the crust of the Arabian Shield. Individual station P-wave (pressure) velocity and S-wave (shear) velocity ratios (VP/VS) are highly variable for the Arabia Plate, ranging from 1.60 to 1.97 and averaging 1.75, with a standard deviation of 0.07. There are no statistically significant differences between VP/VS ratios of the different geologic regions of Saudi Arabia. Similar VP/ VS ratios, coupled with similar crustal thicknesses for harrats and the Arabian Shield, indicate that Cenozoic magmatism has contributed negligibly to crustal growth.

Open-File Report

Ground-water areas and well logs, Central Sevier Valley, Utah

Between September 1959 and June 1960 the United States Geological Survey and the Utah State Engineer, with financial assistance from Garfield, Millard, Piute, Sanpete, and Sevier Counties and from local water-users' associations, cooperated in an investigation to determine the structural framework of the central Sevier Valley and to evaluate the valley's ground-water potential. An important aspect of the study was the drilling of 22 test holes under private contract. These data and other data collected during the course of the larger ground-water investigation of which the test drilling was a part will be evaluated in a report on the geology and ground-water resources of the central Sevier Valley. The present report has been prepared to make available the logs of the test holes and to describe in general terms the availability of ground water in the different areas of the valley. The test holes were located to determine the subsurface geology of the valley, but of principal interest for this report is the water-bearing materials that were penetrated by the test holes. Ten of the holes penetrated materials capable of yielding sufficient water for irrigation; 10 holes penetrated water-yielding materials that could supply water for domestic or stock use; 2 holes were unsuccessful as water prospects but supplied geologic information. Generally, the water in the test holes was of good quality for stock, domestic, or irrigation use, except in test holes 1, 2, 4, 5, 16, 17, and 19 where water from some beds was highly mineralized. Water from the upper water-bearing bed in test holes 1, 2, 4, 5 and 16 and from the 6 upper water-bearing beds in test hole 19 was high in sodium chloride and sodium sulphate and would be unpalatable to humans and stock. The upper water in test hole 17 would be palatable to stock accustomed to brackish water, but the water from below 78 feet is too saline for any use. The central Sevier Valley has been divided into arbitrary ground-water areas that are based in part on topographic and geologic boundaries. The test holes are described by areas downstream from south to north, and the logs of table 1 are arranged from south to north.

Utah

Hydrogeology and groundwater geochemistry of till confining units and confined aquifers in glacial deposits near Litchfield, Cromwell, Akeley, and Olivia, Minnesota, 2014–18

Confined (or buried) aquifers of glacial origin overlain by till confining units provide drinking water to hundreds of thousands of Minnesota residents. The sustainability of these groundwater resources is not well understood because hydraulic properties of till that control vertical groundwater fluxes (leakage) to underlying aquifers are largely unknown. The U.S. Geological Survey, Iowa State University, Minnesota Geological Survey, and Minnesota Department of Health investigated hydraulic properties and groundwater flow through till confining units using field studies and heuristic MODFLOW simulations. Till confining units in the following late-Wisconsinan stratigraphic units (with locations in parentheses) were characterized: Des Moines lobe till of the New Ulm Formation (Litchfield, Minnesota), Superior lobe till of the Cromwell and Aitkin Formations (Cromwell, Minn.), and Wadena lobe till of the Hewitt Formation (hydrogeology field camp [HFC] near Akeley, Minn.). Pre-Illinoian till of the Good Thunder formation (Olivia, Minn.) was also characterized. Hydraulic and geochemical field data were collected from sediment cores and a series of five piezometer nests. Each nest consisted of five to eight piezometers screened at short vertical intervals in hydrostratigraphic units including (if present) surficial aquifers, till confining units, confined/buried aquifers, and underlying bedrock. Till hydraulic conductivity was estimated from slug tests (horizontal [ K h ]) and constant-rate aquifer tests in the confined aquifer (vertical [ K v ]). Travel times through the till were evaluated with Darcy’s law and stable isotope concentrations. A series of heuristic MODFLOW simulations were used to evaluate groundwater fluxes through till across the range of till hydraulic properties and pumping rates observed at the field sites. The field data demonstrated variability in hydraulic properties between and within till stratigraphic units horizontally and vertically. The variability in hydraulic properties within and between sites resulted in substantial differences in groundwater flux through till. A conceptual understanding that emerges from the vertical till profiles is that they are not homogeneous hydrostratigraphic units with uniform properties; rather, each vertical sequence is a heterogeneous mixture of glacial sediment with differing abilities to transmit water. Till thicknesses varied from 60 to 166 feet, and till textures ranged from a sandy loam (Hewitt Formation, HFC site) to a silt loam/clay loam (Good Thunder formation, Olivia site). Till Kh varied by one to three orders of magnitude within each piezometer nest. Four piezometer nests had downward hydraulic gradients ranging from 0.04 to 0.56, and one nest had a slight upward hydraulic gradient of 0.02. The Cromwell, HFC, and Litchfield 1 sites were examples of “leaky” tills with high Kv (0.001 to 1.1 feet per day [ft/d]) and geometric mean Kh (0.03 to 0.07 ft/d) and extensive vertical hydraulic connectivity between the confined aquifer and the overlying till. Estimated groundwater travel times through these sites ranged from 1 to 81 years, and two of these sites had tritium throughout their till profiles. The tills at the other two sites, Olivia and Litchfield 2, were effective confining units that had low Kv (0.001 to 0.0005 ft/d) and geometric mean Kh (0.0002 to 0.004 ft/d). The till piezometers at these sites had no drawdown response to short-term (up to 10 hours for Olivia and up to 5 days for Litchfield) high-capacity pumping from the confined aquifer. Estimated groundwater travel times through the tills at these sites ranged from 165 to nearly 1,800 years, and tritium was only detected in the upper one-third of these till profiles. Across all sites, the till vertical anisotropy (ratio of K h to K v ) ranged by four orders of magnitude from 0.05 at the Cromwell nest to 70 at the Litchfield 1 nest. Stable isotopes of oxygen and hydrogen indicate that groundwater throughout all five till profiles is younger than the last glacial advance into Minnesota at about 11,000 years ago. The heuristic modeling demonstrated that, for understanding sustainability of groundwater pumping from confined aquifers, knowledge of till hydraulic properties is just as important as knowledge of aquifer hydraulic properties. Substantial differences in groundwater fluxes into and through till were observed across hydrogeologic settings representative of the field sites. Over long periods of time (hundreds of years), pumping-induced hydraulic gradients are established in confined aquifer systems and, even in low hydraulic conductivity tills, these pumping-induced hydraulic gradients increase leakage into and through till compared to ambient conditions. In conclusion, groundwater flowing vertically downward through till confining units (leakage) replenishes water pumped from confined aquifers. Till hydraulic properties, such as those presented in this report, provide important information that can be used to quantify leakage rates through till. Till hydraulic properties are variable over short distances and profoundly affect leakage rates, demonstrating the importance of site-specific till hydraulic data for evaluating the sustainability of groundwater withdrawals from confined aquifers.

Minnesota

Plans for a sensitivity analysis of bridge-scour computations

Plans for an analysis of the sensitivity of Level 2 bridge-scour computations are described. Cross-section data from 15 bridge sites in Texas are modified to reflect four levels of field effort ranging from no field surveys to complete surveys. Data from United States Geological Survey (USGS) topographic maps will be used to supplement incomplete field surveys. The cross sections are used to compute the water-surface profile through each bridge for several T-year recurrence-interval design discharges. The effect of determining the downstream energy grade-line slope from topographic maps is investigated by systematically varying the starting slope of each profile. The water-surface profile analyses are then used to compute potential scour resulting from each of the design discharges. The planned results will be presented in the form of exceedance-probability versus scour-depth plots with the maximum and minimum scour depths at each T-year discharge presented as error bars.

Conference Paper

Status and needs for seismic instrumentation of structures along the Hayward fault

The inventory of structures in heavily urbanized communities within the greater San Francisco (SF) Bay area that will experience strong ground motions from the rupture of the Hayward Fault includes a variety of types of recent and older structures built with a variety of materials and to different code standards. Those who remember the effects of the 1989 Loma Prieta earthquake on structures in the San Francisco Bay area also remember the collapse of one upper-deck segment of the Bay Bridge that halted transportation for approximately five weeks. In order to understand how these structures respond to earthquake motions and to improve building practices to resist these strong motions it is imperative that owners of these structures as well as governmental organizations acquire shaking response data from instrumented (or yet to be instrumented structures) during the forecast events. Within California, such data are acquired mainly by California Geological Survey and the United States Geological Survey. A small number of private owners contribute to this effort. The inventory of existing instrumented structures is much less than 0.1% of the total, and thus statistically it is not sufficient. For example, some of the existing important regular or lifeline structures are not instrumented(e.g. Bart Trans-Bay Tunnel, many segments of the Bart elevated structures in the proximity of the Hayward Fault, the yet to be completed eastern part of San Francisco Bay Bridge, Hetch-Hetchy pipeline system crossing the Hayward Fault)even though attempts and proposals have been developed to do so in the past. This paper presents a critical assessment of the status quo and the future needs for instrumentation of structures in the greater SF Bay area that includes the Hayward Fault. There are many new attempts and successes in instrumentation of structures in this region. Two successful examples are provided here, but more needs to be done. The paper does not present new research results; hence, it should be considered to be a “tutorial” paper.

California

Ground-water areas and well logs, central Sevier Valley, Utah

Between September 1959 and June 1960 the United States Geological Survey and the Utah State Engineer, with financial assistance from Garfield, Millard, Piute, Sanpete, and Sevier Counties and from local water-users’ associations, cooperated in an investigation to determine the structural framework of the central Sevier Valley and to evaluate the valley’s ground-water potential. An important aspect of the study was the drilling of 22 test holes under private contract. These data and other data collected during the course of the larger ground-water investigation of which the test drilling was a part will be evaluated in a report on the geology and ground-water resources of the central Sevier Valley. The present report has been prepared to make available the logs of test holes and to describe in general terms the availability of ground water in the different areas of the valley.

Utah

Status of three-dimensional geological mapping and modeling activities in the U.S. Geological Survey

The U.S. Geological Survey (USGS), created in 1879, is the national geological survey for the United States and the sole science agency within its cabinet-level bureau, the Department of the Interior. The USGS has a broad mission, including: serving the Nation by providing reliable scientific information to describe and understand the Earth; minimize loss of life and property from natural disasters; manage water, biological, energy, and mineral resources; and enhance and protect quality of life. USGS scientific activities are organized around major topics, or Mission Areas, aligned with distinct science themes; three-dimensional (3-D) modelling typically supports research and project work within a specific Mission Area. The vastness, diversity, and complexity of the geological landscape of the United States has resulted in the creation of 3-D geological framework models that are local or regional in scale; a National-scale 3-D model is only beginning to evolve. This paper summarizes 3-D geological modeling at the USGS and does not discuss 3-D modeling that is conducted by other Federal agencies, state geological surveys, academia, or industry within the U.S. This paper updates and expands upon a similar status report of USGS 3-D modeling activities of Jacobsen et al. (2011).

Report

Geologic and geophysical maps of the Stockton 30’ × 60’ quadrangle, California

This pamphlet and accompanying geologic and geophysical maps are the products of cooperative efforts by the California Geological Survey (CGS) and United States Geological Survey (USGS) to compile a comprehensive, digital representation of the bedrock geology, Quaternary surficial deposits, and potential-field anomalies within the boundaries of the Stockton 30’ × 60’ quadrangle. The Stockton 30’ × 60’ quadrangle covers approximately 4,890 km 2 of Contra Costa, Alameda, San Joaquin, and Stanislaus Counties, California. From the rugged hillsides of the northern Diablo Range in the west to the San Joaquin Valley in the east, the map extends roughly 88 km across growing suburban communities of the eastern San Francisco Bay Area and Livermore Valley, grass-covered ranchlands along eastern slopes of the Diablo Range, and into the low farmlands of the San Joaquin Valley and Sacramento-San Joaquin River Delta (Figure 1). The elevation ranges from near sea level in the Delta to 1,173 meters on Mt. Diablo, the most prominent peak of the San Francisco Bay region.

California

Stream measurement work: Chapter 8 in Seventeenth biennial report of the State Engineer to the governor of Utah: 1929-1930

General stream measurement work looking toward a comprehensive inventory of the water resources of the state has been continued during the biennium by the United States Geological Survey under the usual cooperative agreement with the State Engineer. Since 1909 Utah in company with many other states has made regular legislative appropriations for the purpose of assisting and hastening the determination of the water supply of the United States by the Geographical Survey. Because of the comparatively small Federal appropriations the scope of this wok in the individual states has been largely influenced by the amount of the state cooperation. The funds contributed by each state have all been expended within that state and matched as far as possible by funds of the Geographical Survey. Up to the present, however, the Federal funds have been insufficient to match the state contributions beyond a very limited amount and in many localities the large amount of work done has been made possible only by correspondingly large unmatched state appropriations. During this period the regular stream gaging work in Utah has been practically limited to that possible with approximately ten thousand dollars annually divided about equally between the state and Geological Survey with the government’s share including the cost at Washington of general supervision, and the review, editing, and publication of the records. This has been the maximum amount that it has been possible to allot any one state to meet state cooperation.

Utah

Ground-water data collected in the Missouri River basin units in Kansas during 1953

Ground-water studies in the Missouri River basin were begun by the United States Geological Survey during the fall of 1945 as a part of a program for the development of the resources of the basin by the United States Bureau of Reclamation and other Federal Agencies. The studies of the ground-water resources in the part of Kansas that lies within the Missouri River basin have been coordinated with the cooperative program of ground water studies which were already being made in Kansas by the U. S. Geological Survey, the State Geological Survey of Kansas, the Division of Sanitation of the Kansas State Board of Health, and the Division of Water Resources of the Kansas State Board of Agriculture. Areas in which ground-water data have been and are being collected are the following: Almena unit in Norton and Phillips Counties; Bostwick unit in Jewell, Republic, and Cloud Counties; Cedar Bluff unit in Ellis, Rush, and Trego Counties; Glen Elder unit in Mitchell County; Kanopolis unit in Ellsworth, McPherson, and Saline Counties; Kirwin unit in Phillips, Smiths and Osborne Counties; St. Francis unit in Cheyenne County; Webster unit in Osborne County; and Wilson unit in Lincoln County. (See fig. 1.) Data relating to the Ladder Creek project in Greeley, Gove, Lane, Logan, Scott, Wallace, and Wichita Counties will be published later in a separate report.

Kansas

Digital Mapping Techniques '11–12 workshop proceedings

The Digital Mapping Techniques '11 (DMT'11) workshop was hosted by Virginia Division of Geology and Mineral Resources and The College of William & Mary, and coordinated by the National Geologic Map Database project. Conducted May 22-25 on the campus of The College of William & Mary, in Williamsburg, Virginia, it was attended by 77 technical experts from 30 agencies, universities, and private companies, including representatives from 19 State geological surveys (see "DMT'11 Presentations and Attendees" in these Proceedings). The Digital Mapping Techniques '12 (DMT'12) workshop was hosted by the Illinois State Geological Survey and coordinated by the National Geologic Map Database project. Conducted May 20-23 on the campus of The University of Illinois, in Champaign, Illinois, it was attended by 73 technical experts from 34 agencies, universities, and private companies, including representatives from 25 State geological surveys (see "DMT'12 Presentations and Attendees" in these Proceedings). At these meetings, oral and poster presentations and special discussion sessions emphasized: (1) methods for creating and publishing map products (here, "publishing" includes Web-based release); (2) field data capture software and techniques, including the use of LiDAR; (3) digital cartographic techniques; (4) migration of digital maps into ArcGIS Geodatabase formats; (5) analytical GIS techniques; and (6) continued development of the National Geologic Map Database.

Open-File Report

A multiagency and multijurisdictional approach to mapping the glacial deposits of the Great Lakes region in three dimensions

The Great Lakes Geologic Mapping Coalition (GLGMC), consisting of state geological surveys from all eight Great Lakes states, the Ontario Geological Survey, and the U.S. Geological Survey, was conceived out of a societal need for unbiased and scientifically defensible geologic information on the shallow subsurface, particularly the delineation, interpretation, and viability of groundwater resources. Only a small percentage (<10%) of the region had been mapped in the subsurface, and there was recognition that no single agency had the financial, intellectual, or physical resources to conduct such a massive geologic mapping effort at a detailed scale over a wide jurisdiction. The GLGMC provides a strategy for generating financial and stakeholder support for three-dimensional (3-D) geologic mapping, pooling of physical and personnel resources, and sharing of mapping and technological expertise to characterize the thick cover of glacial sediments. Since its inception in 1997, the GLGMC partners have conducted detailed surficial and 3-D geologic mapping within all jurisdictions, and concurrent significant scientific advancements have been made to increase understanding of the history and framework of geologic processes. More importantly, scientific information has been provided to public policymakers in understandable formats, emphasis has been placed on training early-career scientists in new mapping techniques and emerging technologies, and a successful model has been developed of state/provincial and federal collaboration focused on geologic mapping, as evidenced by this program's unprecedented and long-term successful experiment of 10 geological surveys working together to address common issues.

GSA Special Papers