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USGS1924

The data of geochemistry

Upon the subject of geochemistry a vast literature exists, but it is widely scattered and portions of it are difficult of access. The general treatises, like the classical works of Bischof and of Koth, are not recent, and great masses of modern data are as yet uncorrelated. The American material alone is singularly rich, but most of it has been accumulated since Roth's treatise was published. The science of chemistry, moreover, has undergone great changes during the last 25 years, and many subjects now appear under new and generally unfamiliar aspects. The methods and principles of physical chemistry are being more and more applied to the solution of geochemical problems, 1 as is shown by the well-known researches of Van't Hoff upon the Stassfurt salts and the magmatic studies of Vogt, Doelter, and others. The great work in progress at the geophysical laboratory of the Carnegie Institution is another illustration of the change now taking place in geochemical investigation. To bring some of the data together, to formulate a few of the problems and to present certain general conclusions in their modern form are the purposes of this memoir. It is not an exhaustive monograph upon geochemistry, but rather a critical summary of what is now known, and a guide to the more important literature of the subject. If it does no more than to make existing data available to the reader, its preparation will be justified.

Bulletin↗

USGS1962

An interim report on Sacramento River Chinook disease: A virus-like disease of Chinook salmon

An annually recurring disease among chinook salmмом ( Oncorhynchus tahawytscha ) FINGERLINGs at the National Fish Hatchery at Coleman, California, was reported by Ross, Pelnar, and Rucker (1960). They presented results of experimental investigation of the disease which established that the etiologic agent was filterable, highly virulent, and resistant to antibiotics and some of the more common chemicals, and that it was apparently not transmitted in salmon product-used as food, as was shown for a virus disease of sockeye salmon ( O. merka ) by Guenther, watson, and Rucker (T559). Also, Ross and his co-workers (1960) indicated a relation between temperature and incidence of the disease, and speculated on the possibility of the agent's being a virus.

Progressive Fish-Culturist↗

USGS1973

Microbial degradation of the lamprey larvicide 3-trifluoromethyl-4-nitrophenol in sediment-water systems

The selective lampricide 3-trifluoromethyl-4-nitrophenol (TFM), maintained in the water at concentrations of 1 to 6 I?g/ml for several hours, kills larval sea lampreys (Petromyzon marinus) in tributaries of the Great Lakes. Because the fate of TFM in the environment is a matter of concern, the interactions of this chemical with river and lake sediments were studied in laboratory experiments. In mixtures of TFM, water, and sediment held in aquariums, the TFM decreased progressively and nearly or completely disappeared in 1 to 4 weeks; concentrations of the fluoride ion increased; and the systems became nontoxic for sea lamprey larvae and goldfish (Carassius auratus). If the reduction in TFM ceased before all of the chemical had disappeared, the process resumed when nutrient broth was added. Loss of TFM from the systems was prevented by the addition of an antiseptic (phenol) and by heat sterilization. Enrichment cultures of microorganisms isolated from stream and lake sediments degraded TFM in nutrient broths. I conclude that TFM is degraded by microorganisms that live in sediment-water systems.

Technical Report↗

USGS2017

Long-term flow-through column experiments and their relevance to natural granitoid weathering rates

Four pairs of fresh and partly-weathered granitoids, obtained from well-characterized watersheds—Merced River, CA, USA; Panola, GA, USA; Loch Vale, CO, USA, and Rio Icacos, Puerto Rico—were reacted in columns under ambient laboratory conditions for 13.8 yrs, the longest running experimental weathering study to date. Low total column mass losses (<1 wt. %), correlated with the absence of pitting or surface roughening of primary silicate grains. BET surface area (S BET ) increased, primarily due to Fe-oxyhydroxide precipitation. Surface areas returned to within factors of 2 to 3 of their original values after dithionite extraction. Miscible displacement experiments indicated homogeneous plug flow with negligible immobile water, commonly cited for column experiments. Fresh granitoid effluent solute concentrations initially declined rapidly, followed by much slower decreases over the next decade. Weathered granitoid effluent concentrations increased modestly over the same time period, indicating losses of natural Fe-oxide and/or clay coatings and the increased exposure of primary mineral surfaces. Corresponding (fresh and weathered) elemental effluent concentrations trended toward convergence during the last decade of reaction. NETPATH/PHREEQC code simulations indicated non-stoichiometric dissolution involving Ca release from disseminated calcite and excess K release from interlayer biotite. Effluent 87 Sr/ 85 Sr ratios reflected a progressive weathering sequence beginning and ending with 87 Sr/ 85 Sr values of plagioclase with an additional calcite input and a radiogenic biotite excursion proportional to the granitoid ages. Effluents became thermodynamically saturated with goethite and gibbsite, slightly under-saturated with kaolinite and strongly under-saturated with plagioclase, consistent with kinetically-limited weathering in which solutes such as Na varied with column flow rates. Effluent Na concentrations showed no clear trend with time during the last decade of reaction (fresh granitoids) or increased slowly with time (weathered granitoids). Analysis of cumulative Na release indicated that plagioclase dissolution achieved steady state in 3 of the 4 fresh granitoids during the last decade of reaction. Surface-area normalized plagioclase dissolution rates exhibited a narrow range (0.95 to 1.26 10 -13 moles m -2 s -1 ), in spite of significant stoichiometric differences (An 0.21 to An 0.50 ). Rates were an order of magnitude slower than previously reported in shorter duration experiments but generally 2 to 3 orders of magnitude faster than corresponding natural analogs. CrunchFlow simulations indicated that more than a hundredfold decrease in column flow rates would be required to produce near-saturation reaction affinities that would start to slow plagioclase weathering to real-world levels. Extending simulations to approximate long term weathering in naturally weathered profiles required additional decreases in the intrinsic plagioclase dissolution and kaolinite precipitation rates and relatively large decreases in the fluid flow rate, implying that exposure to reactive mineral surfaces is significantly limited in the natural environment compared to column experiments.

Geochimica et Cosmochimica Acta↗

USGS2010

The coefficient of friction of chrysotile gouge at seismogenic depths

We report new strength data for the serpentine mineral chrysotile at effective normal stresses, σ n between 40 and 200 MPa in the temperature range 25°-280°C. Overall, the coefficient of friction, μ (= shear stress/effective normal stress) of water-saturated chrysotile gouge increases both with increasing temperature and σ n , but the rates vary and the temperature-related increases begin at ~100°C. As a result, a frictional strength minimum (μ = 0.1) occurs at low σ n at about 100°C. Maximum strength (μ = 0.55) results from a combination of high normal stress and high temperature. The low-strength region is characterized by velocity strengthening and the high-strength region by velocity-weakening behavior. Thoroughly dried chrysotile has μ = 0.7 and is velocity-weakening. The frictional properties of chrysotile can be explained by its tendency to adsorb large amounts of water that acts as a lubricant during shear. The water is progressively driven off the fiber surfaces with increasing temperature and pressure, causing chrysotile to approach its dry strength. Depth profiles for a chrysotile-lined fault constructed from these data would pass through a strength minimum at ~3 km depth, where sliding should be stable. Below that depth, strength increases rapidly as does the tendency for unstable (seismic) slip. Such a trend would not have been predicted from the room-temperature data. These results therefore illustrate the potential hazards of extrapolating room-temperature friction data to predict fault zone behavior at depth. This depth profile for chrysotile is consistent with the pattern of slip on the Hayward fault, which creeps aseismically at shallow depths but which may be locked below 5 km depth.

International Geology Review↗

USGS2007

Strategic Plan for the North American Breeding Bird Survey: 2006-2010

Executive Summary The mission of the North American Breeding Bird Survey (BBS) is to provide scientifically credible measures of the status and trends of North American bird populations at continental and regional scales to inform biologically sound conservation and management actions. Determining population trends, relative abundance, and distributions of North American avifauna is critical for identifying conservation priorities, determining appropriate conservation actions, and evaluating those actions. The BBS program, jointly coordinated by the U.S. Geological Survey and Environment Canada’s Canadian Wildlife Service, provides the U.S. and Canadian Federal governments, state and provincial agencies, other conservation practitioners, and the general public with science-based avian population trend estimates and other information for regional and national species’ population assessments. Despite the demonstrated value of the BBS for furthering avian conservation across North America, its importance is often underappreciated, and it is underfunded compared with many other government-supported programs that report on status of the environment. Today, BBS resources, adjusted for inflation, are below the amount allocated in the 1970s and are still only sufficient to support two biologists. Yet the number of routes, participants, data, and data requests has quadrupled. Data and information management and delivery requirements and security concerns, non-existent in 1966, impose further demands on BBS resources. In addition, the Mexican expansion of the BBS offers new hope for a truly continental approach to avian conservation, but also brings additional challenges. Meeting the goals of this plan will take cooperation among myriad stakeholders; yet, even with collaboration, most objectives of this plan will be unattainable if BBS program support is not increased. The BBS developed this strategic plan to help set priorities and identify resources required for the program to continue to meet the evolving needs of the conservation community for information on bird population change. By setting clear goals, strategies, and measures of success, this plan provides a cohesive framework and vision for maintenance and development of the BBS. The plan identifies two major goals for the BBS, with a number of strategies and objectives to achieve these goals. Over the next 5 years, progress made in addressing each long-term goal and its associated 5-year strategies and objectives will gage the plan’s success. Specific actions, projected outcomes, and measures of success related to accomplishing these are outlined in Table 1, with a timeline in Table 2. The two main goals for the program, with a summary of the strategies to achieve them, are: Goal 1: Collect scientifically credible measures of the status and trends of North American bird populations at continental and regional scales. The North American Breeding Bird Survey will continue to support North American natural resource conservation through the collection of scientifically credible measures of the status and trends of continental bird populations. While doing this, the BBS will work to improve the science behind the program to better meet its mission and the changing needs of the avian conservation community. In partnership with collaborators, the BBS will address detection probability bias and habitat bias, improve analytical methods, and more fully assess and account for observer quality. Moreover, the BBS will improve the quality and breadth of avian population data through strategic increases in route density and the establishment of a Mexican BBS program. Goal 2: Ensure BBS data and analytical results are widely available and easily accessible for use by the avian conservation and management communities. At the heart of the BBS lies a four-million-record database containing more than 40 years of data on more than 600 bird species. These data are of no value if not well maintained, appropriately analyzed, and widely and easily accessible. The USGS has greatly improved data management and accessibility in recent years. Trend estimates were first made available via the Internet in the mid-1990s, followed closely by the raw data with baseline metadata and standard operating procedures. Nevertheless, numerous enhancements to data management and the usability of BBS results will greatly improve the ability of the BBS to serve avian conservation goals. The BBS needs to ensure that BBS data and results presented on the web site use the best data-management practices and statistical methods, with adequate documentation for users to understand them and any differences between different trend estimates. Moreover, the BBS needs to increase communication with BBS partners and stakeholders to ensure that it continues to meet the avian population status and trends needs of the conservation community and to encourage the development of new products. Working with collaborators, the BBS will develop tools for integrating environmental parameters like habitat change into the analyses, and for integrating BBS data with other avian survey results. In addition, the BBS will continue to improve data and database management through the incorporation of additional data and data fields, such as georeferenced stop locations and more complete metadata for the raw data and results, thus enhancing the uses that can be made of the data.

Circular↗

USGS2007

Tectonics of the West Antarctic rift system: new light on the history and dynamics of distributed intracontinental extension

The West Antarctic rift system (WARS) is the product of multiple stages of intracontinental deformation from Jurassic to Present. The Cretaceous rifting phase accomplished >100 percent extension across the Ross Sea and central West Antarctica, and is widely perceived as a product of pure shear extension orthogonal to the Transantarctic Mountains that led to breakup and opening of the Southern Ocean between West Antarctica and New Zealand. New structural, petrological, and geochronological data from Marie Byrd Land reveal aspects of the kinematics, thermal history, and chronology of the Cretaceous intracontinental extension phase that cannot be readily explained by a single progressive event. Elevated temperatures in "Lachlan-type" crust caused extensive crustal melting and mid-crustal flow within a dextral transcurrent strain environment, leading to rapid extension and locally to exhumation and rapid cooling of a migmatite dome and detachment footwall structures. Peak metamorphism and onset of crustal flow that brought about WARS extension between 105 Ma and 90 Ma is kinematically, temporally, and spatially linked to the active convergent margin system of East Gondwana. West Antarctica-New Zealand breakup is distinguished as a separate event at 83-70 Ma, from the standpoint of kinematics and thermal evolution

Open-File Report↗

USGS2014

A field trip guidebook to the type localities of Marland Billings' 1935 Paleozoic bedrock stratigraphy near Littleton, New Hampshire

Marland Billings' classic paper published in 1937 in the Geological Society of America Bulletin established a succession of six stratigraphic units in rocks of low metamorphic grade near Littleton, New Hampshire. The two youngest units are fossiliferous in the area, with ages established at the time as “middle” Silurian and Early Devonian. Billings and students mapped the same stratigraphic section in adjacent areas of progressively higher regional metamorphic grade. This work laid the foundation upon which a major part of subsequent work in New England has been directly or indirectly built. This guidebook was written for a field trip held in March 2013 to visit roadcuts that are as close as possible in March to the type localities or areas of Billings’ six-fold stratigraphic succession. Ten stops are in rocks of chlorite grade of Acadian(?) metamorphism; the final stop visits amphibolite of the Ammonoosuc Volcanics. Fieldwork by the authors over the past 20 years confirms Billings’ broad conclusions.

New Hampshire↗

USGS1964

Sea water in coastal aquifers

Investigations in the coastal part of the Biscayne aquifer, a highly productive aquifer of limestone and sand in the Miami area, Florida, show that the salt-water front is dynamically stable as much as 8 miles seaward of the position computed according to the Ghyben-Herzberg principle. This discrepancy results, at least in part, from the fact that the salt water in the Biscayne aquifer is not static, as explanations of the dynamic balance commonly assume. Cross sections showing lines of equal fresh-water potential indicate that during periods of heavy recharge, the fresh-water head is high enough to cause the fresh water, the salt water, and the zone of diffusion between them to move seaward. When the fresh-water head is low, salt water in the lower part of the aquifer intrudes inland, but some of the diluted sea water in the zone of diffusion continues to flow seaward. Thus, salt water circulates inland from the floor of the sea through the lower part of the aquifer becoming progressively diluted with fresh water to a line along which there is no horizontal component of flow, after which it moves upward and returns to the sea. This cyclic flow is demonstrated by a flow net which is constructed by the use of horizontal gradients determined from the low-head equipotential diagram. The flow net shows that about seven-eights of the total discharge at the shoreline originates as fresh water in inland parts of the aquifer. The remaining one-eighth represents a return of sea water entering the aquifer through the floor of the sea.

Water Supply Paper↗

USGS1961

The use of merthiolate on green eggs of the Chinook salmon

MERTHIOLATE has been used as a disinfecting agent for green and eyed eggs of various species (Gee and Sarles 1942, Snieszko and Friddle 1948). The present report is a description of the effects of the chemical on green eggs of the chinook salmon ( Oncorhynchus tshawytscha ). The need for this study was indicated when a program of transporting green chinook eggs from various sources to the Coleman National Fish Hatchery at Anderson, California, was required as part of a disease study. There was no available information to indicate whether the salmon eggs would withstand the disinfecting routine shown by Snieszko and Friddle (1948) to be tolerated by trout eggs, or whether the fry and fingerlings from salmon eggs so treated would suffer high mortalities or be abnormal in appearance or activity.

Progressive Fish-Culturist↗

USGS1972

Physical, chemical, and biological aspects of the Duwamish River Estuary, King County, Washington, 1963-67

This report describes the significant results to 1967 of a comprehensive study that began in 1963 to evaluate what changes take place in an estuary as the loads .of raw and partially treated industrial and municipal wastes are replaced by effluent from a secondary treatment plant. The study area is the Duwamish River estuary, about 18.3 river kilometers long. At mean sea level the estuary has a water-surface area of about 1 square mile and a mean width of 440 feet. At the lowest and highest recorded tides, the volume of the estuary is about 205 and 592 million cubic feet, respectively. The estuary is well stratified (salt-wedge type) at fresh-water inflows greater than 1,000 cfs (cubic feet per second), but when inflow rates are less than 1,000 cfs the lower 5.6 kilometers of the estuary grades into the partly mixed type. The crosschannel salinity distribution is uniform for a given location and depth. Salinity migration is controlled by tides and fresh-water inflow. At fresh-water inflow rates greater than 1,000 cfs, water in the upper 8.4 kilometers of the estuary is always fresh regardless of tide. At inflow rates less than 600 cfs and tide heights greater than 10 feet; some salinity has been detected 16.1 kilometers above the mouth of the estuary. Studies using a fluorescent dye show that virtually no downward mixing into the salt wedge occurs; soluble pollutants introduced at the upper end of the estuary stay in the surface layer (5-15 ft thick). On the basis of dye studies when fresh-water inflow is less than 400 cfs, it is estimated that less than 10 percent of a pollutant will remain in the estuary a minimum of 7 days. Longitudinal dispersion coefficients for the surface layer have been determined to be on the order of 100-400 square feet per second. Four water-quality stations automatically monitor DO (dissolved oxygen), water temperature, pH, and specific conductance; at one station solar radiation also is measured. DO concentration in the surface layer decreases almost linearly in a downstream direction. Minimum DO concentration in the surface layer is usually greater than 4 rag/1 (milligrams per liter). The smallest DO values are consistently recorded in the bottom layer at the station 7.7 kilometers above the mouth; monthly means of less than 3 mg/1 of DO have occurred at this point. Manual sampling shows that the DO sag in the bottom layer oscillates between 7.7 and 10.4 kilometers above the mouth of the estuary. Multiple-regression analysis shows that the surface DO content can be estimated from the fresh-water inflow and water temperature. Tidal exchange and fresh-water inflow indirectly control the bottom DO content. Information available from previous studies failed to indicate a progressive decrease in DO content during the period 1949-56, but data from the present study suggest a slight general decrease in the annual minimum DO concentrations in both the upper and lower layers. Average nitrate concentration in fresh water at station 16.2 has increased progressively since 1964, by amounts greater than those which can be attributed to the Renton Treatment Plant, 4.3 kilometers upstream from station 16.2. The BOD (biochemical oxygen demand) in both surface and bottom layers is generally less than 4 rag/1 of oxygen, but values greater than 6 rag/1 have been measured during a period of phytoplankton bloom. Phytoplankton blooms can occur during periods of minimum tidal exchange and fresh-water inflows of less than 300 cfs if solar radiation and water temperature are optimum. Nutrients (nitrogen and phosphorus compounds) do not control the occurrence of a bloom, because sufficient quantities of these nutrients are always present. Nutrients in the treated effluent may increase the biomass of the bloom. Trace-element studies have not defined any role that these elements may play in algal growth. The inflowing fresh water contains principally calcium and bicarbonate and has a dissolved-solids content ra

Water Supply Paper↗

USGS2025

The 3D Elevation Program—Supporting the economy of Massachusetts

Introduction Massachusetts extends from the mountains of the Appalachian system in the west of the State to the sandy beaches and rocky shorelines of the Atlantic coast in the east. Inland topographic data support a wide range of important activities, including geologic mapping, transportation planning, forest and wildlife management, quantifying ecological services, water supply protection, commonwealth-wide infrastructure planning, local site planning, and flood-plain management. Nearshore bathymetry can be used to support coastal portions of the Commonwealth by addressing the combined threats of ocean warming, strong storm surge, and rising sea levels. The maintenance and (or) expansion of Massachusetts ports (for instance, Boston, New Bedford) and Cape Cod sediment management depends upon the accurate mapping of bathymetry and the frequent influx of sediment and redeposition. Critical applications that address the broad range of requirements depend on light detection and ranging (lidar) data that provide a highly detailed three-dimensional (3D) model of the Earth’s surface and aboveground features. The 3D Elevation Program (3DEP) is managed by the U.S. Geological Survey (USGS) in partnership with Federal, State, Tribal, U.S. territorial, and local agencies to acquire consistent lidar coverage at quality level 2 or better to meet the many needs of the Nation and Massachusetts. The status of available and in-progress 3DEP baseline lidar data in Massachusetts is shown in figure 1. 3DEP baseline lidar data include quality level 2 or better, 1-meter or better digital elevation models, and lidar point clouds, and must meet the Lidar Base Specification version 1.2 ( https://www.usgs.gov/3dep/lidarspec ) or newer requirements. The National Enhanced Elevation Assessment identified user requirements and conservatively estimated that availability of lidar data would result in at least $1.23 million in new benefits annually to Massachusetts. The top 10 Massachusetts business uses for 3D elevation data, which are based on the estimated annual conservative benefits of 3DEP, are shown in table 2.

Massachusetts↗

USGS1993

Water-resources investigations in Pennsylvania; programs and activities of the U.S. Geological Survey, 1993

Current activities of the Pennsylvania District of the USGS are described and include information on current projects, such as project objectives, approach, progress and plans, project location, cooperators, period of project, and project chief. Basic-data programs for surface water, ground water, and quality of water also are described. Also included is information on the basic mission and programs of the USGS; program funding and cooperation for fiscal year 1993; the USGS water- data program, National Water-Data Exchange, and National Water-Data Storage and Retrieval System; and Pennsylvania data-collection programs and hydrologic investigations. List of publications of the Pennsylvania District and maps published by the USGS, as well as information on how to obtain them, are included.

Open-File Report↗

USGS2015

Revised hydrogeologic framework of the Floridan aquifer system in Florida and parts of Georgia, Alabama, and South Carolina

The hydrogeologic framework for the Floridan aquifer system has been revised throughout its extent in Florida and parts of Georgia, Alabama, and South Carolina. The updated framework generally conforms to the original framework established by the U.S. Geological Survey in the 1980s, except for adjustments made to the internal boundaries of the Upper and Lower Floridan aquifers and the individual higher and contrasting lower permeability zones within these aquifers. The system behaves as one aquifer over much of its extent; although subdivided vertically into two aquifer units, the Upper and Lower Floridan aquifers. In the previous framework, discontinuous numbered middle confining units (MCUI–VII) were used to subdivide the system. In areas where less-permeable rocks do not occur within the middle part of the system, the system was previously considered one aquifer and named the Upper Floridan aquifer. In intervening years, more detailed data have been collected in local areas, resulting in some of the same lithostratigraphic units in the Floridan aquifer system being assigned to the Upper or Lower Floridan aquifer in different parts of the State of Florida. Additionally, some of the numbered middle confining units are found to have hydraulic properties within the same order of magnitude as the aquifers. A new term “composite unit” is introduced for lithostratigraphic units that cannot be defined as either a confining or aquifer unit over their entire extent. This naming convention is a departure from the previous framework, in that stratigraphy is used to consistently subdivide the aquifer system into upper and lower aquifers across the State of Florida. This lithostratigraphic mapping approach does not change the concept of flow within the system. The revised boundaries of the Floridan aquifer system were mapped by considering results from local studies and regional correlations of lithostratigraphic and hydrogeologic units or zones. Additional zones within the aquifers have been incorporated into the framework to allow finer delineation of permeability variations within the aquifer system. These additional zones can be used to progressively divide the system for assessing groundwater and surface-water interaction, saltwater intrusion, and offshore movement of groundwater at greater detail if necessary. The lateral extent of the updip boundary of the Floridan aquifer system is modified from previous work based on newer data and inclusion of parts of the updip clastic facies. The carbonate and clastic facies form a gradational sequence, generally characterized by limestone of successively younger units that extend progressively farther updip. Because of the gradational nature of the carbonate-clastic sequence, some of the updip clastic aquifers have been included in the Floridan aquifer system, the Southeastern Coastal Plain aquifer system, or both. Thus, the revised updip limit includes some of these clastic facies. Additionally, the updip limit of the most productive part of the Floridan aquifer system was revised and indicates the approximate updip limit of the carbonate facies. The extent and altitude of the freshwater-saltwater interface in the aquifer system has been mapped to define the freshwater part of the flow system.

Alabama, Florida, Georgia, South Carolina↗

USGS1915

Erosion and sedimentation in Chesapeake Bay around the mouth of Choptank River

With the unfolding of geologic knowledge during the last century the processes of denudation, transportation of sediments, and sedimentation have become better understood, and to some extent their relative effects in bringing about the present configuration of the earth's surface have been determined. The nature of these processes has been studied in many parts of the globe, but owing to the large size of the units affected and the slowness of the processes there has been little opportunity to collect quantitative data. Indeed, the data available are very largely conjectural, their degree of accuracy being only that of good guessing. However, with the advent of accurate topographic and hydrographic surveys, the first steps toward actual measurements of some of the many interesting surficial changes that are in progress have been taken, and it only remains for time and additional observations to afford opportunities for comparison. Resurveys, particularly by the United States Coast and Geodetic Survey, of parts of the eastern coast of the United States at different intervals have shown in many places marked changes of both shore line and sea bottom, as on Cape Cod, on Nantucket Island, and in Delaware Bay. Comparisons of this kind have so far been incidental to work in engineering and coast surveying, so that there has been little opportunity for the selection of localities particularly adapted to studies of erosion and sedimentation.

Maryland↗

USGS1979

Effects of urbanization on the magnitude and frequency of floods in northeastern Illinois

Changes in land use associated with urbanization have increased flood-peak discharges in northeastern Illinois by factors up to 3.2. Techniques are presented for estimating the magnitude and frequency of floods in the urban environment of northeastern Illinois, and for estimating probable changes in flood characteristics that may be expected to accompany progressive urbanization. Suggestions also are offered for estimating the effects of urbanization on flood characteristics in areas other than northeastern Illinois. Three variables, drainage area, channel slope, and percent imperviousness (an urbanization factor), are used to estimate flood magnitudes for frequencies ranging from 2 to 500 years. Multiple regression analyses were used to relate flood-discharge data to the above watershed characteristics for 103 gaged watersheds. These watersheds ranged in drainage area from 0.07 to 630 square miles, in channel slope from 1.1 to 115 feet per mile, and in imperviousness from 1 to 39 percent.

Illinois↗

USGS1876

Notes on the geology of northeastern New Mexico

In the region of the headwaters of the Canadian is embraced a territory which, for the completeness of its geological record and the interest of its concomitant topographical and scenic features, is not excelled perhaps by a similar extent of country in the West. It is bounded on the west by the Spanish range, which in this part of its course consists of a densely-wooded watershed-divide, 9,000 to 11,000 feet in altitude, from which at intervals lofty lateral spurs are thrown off, whose bald summits overtop by 1,000 to 2,000 feet the actual watershed, which latter extends in a general north-south direction. Near the Colorado line, the range is intersected by the Raton Mountains, a range of gladed hills extending eastward forty or fifty miles, and constituting, with the still easterly prolongation in the Chicorica Mesa, the northern limits of the district, which opens out to the southeastward into the great plain. Thus defined, the district comprises an area of about twenty-five hundred square miles. During the season of 1869, in the progress of his extended reconnaissance of the Rocky Mountains, Dr. Hayden visited this region, from whom we have authentic account of its general geological features, and their intimate relation to those prevailing in other and similar districts to the north and south. A few months' residence in this part of the country in 1874-'75* afforded the writer opportunity to become somewhat familiar with its geological features; and the purpose of the present communication is to present such facts as may tend to contribute something toward a similar knowledge of remote and perhaps hitherto rarely-visited localities, and their connection with already examined districts.

New Mexico↗

USGS2024

The 3D Elevation Program—Supporting the Kansas Economy

Introduction High-resolution elevation data for Kansas inform decision making to improve the State’s economy. Existing elevation data coverage is used to support State water planning initiatives, facilitate infrastructure management, and improve resilience to natural disasters. The expanding availability of current and more accurate elevation data helps better support natural resources conservation, agriculture and precision farming, flood risk management, water supply planning, infrastructure and construction management, and geologic resource assessment and hazard mitigation. Critical applications that meet the State’s management needs depend on light detection and ranging (lidar) data that provide a highly detailed three-dimensional (3D) model of the Earth’s surface and aboveground features. The 3D Elevation Program (3DEP) is managed by the U.S. Geological Survey (USGS) in partnership with Federal, State, Tribal, U.S. territorial, and local agencies to acquire consistent lidar coverage at quality level 2 or better to meet the many needs of the Nation and Kansas. The status of available and in-progress 3DEP baseline lidar data in Kansas is shown in figure 1. 3DEP baseline lidar data include quality level 2 or better, 1-meter or better digital elevation models, and lidar point clouds, and must meet the Lidar Base Specification version 1.2 ( https://www.usgs.gov/3dep/lidarspec ) or newer requirements. The National Enhanced Elevation Assessment identified user requirements and conservatively estimated that availability of lidar data would result in at least $14.41 million in new benefits annually to the State. The top nine Kansas business uses for 3D elevation data, which are based on the estimated annual conservative benefits of 3DEP, are shown in table 2.

Kansas↗