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Water resources data, Pennsylvania, water year 2000. Volume 2. Susquehanna and Potomac River Basins

Introduction The Water Resources Division of the U.S. Geological Survey, in cooperation with State, municipal, and Federal agencies, collects a large amount of data pertaining to the water resources of Pennsylvania each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, these data are published annually in this report series entitled "Water Resources Data - Pennsylvania, Volumes 1, 2, and 3." Volume 1 contains data for the Delaware River Basin; Volume 2, the Susquehanna and Potomac River Basins; and Volume 3, the Ohio and St. Lawrence River Basins. This report, Volume 2, contains: (1) discharge records for 83 continuous-record streamflow-gaging stations, 16 partial-record stations, and 24 special study and miscellaneous streamflow sites; (2) elevation and contents records for 12 lakes and reservoirs; (3) water-quality records for 11 streamflow gaging stations and 70 partial-record and project stations; and (4) water-level records for 30 ground-water network observation wells and water-quality analyses of ground water from 8 wells; and (5) water-quality analyses at 60 special study ground-water wells. Additional water data collected at various sites not involved in the systematic data-collection program may also be presented. Publications similar to this report are published annually by the Geological Survey for all States. For the purpose of archiving, these official reports have an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as "U.S. Geological Survey Water-Data Report PA-00-2." These water-data reports, beginning with the 1971 water year, are for sale as paper copy or microfiche by the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161. The annual series of Water Data Reports for Pennsylvania began with the 1961 water-year report and contained only data relating to quantities of surface water. With the 1964 water year, a companion report (part 2) was introduced that contained only data relating to water quality. Beginning with the 1975 water year the report was changed to three volumes (by river basin), with each volume containing data on quantities of surface water, quality of surface and ground water, and ground-water levels. Prior to the introduction of this series and for several years concurrent with it, water-resources data for Pennsylvania were published in U.S. Geological Survey Water-Supply Papers. Data on stream discharge and stage, and on lake or reservoir contents and stage, through September 1960, were published annually under the title "Surface-Water Supply of the United States," which was released in numbered parts as determined by natural drainage basins. For the 1961-70 water years, these data were published in two 5-year reports. Data prior to 1961 are included in two reports: "Compilation of Records of Surface Waters of the United States through 1950," and "Compilation of Records of Surface Waters of the United States, October 1950 to September 1960." Data for Pennsylvania are published in Parts 1, 3, and 4. Data on chemical quality, temperature, and suspended sediment for the 1941-70 water years were published annually under the title "Quality of Surface Waters of the United States," and ground-water levels for the 1935-74 water years were published annually under the title "Ground-Water Levels in the United States." The above mentioned Water-Supply Papers may be consulted in the libraries of the principal cities of the United States and may be purchased from the U.S. Geological Survey, Information Services, Box 25286, Denver, CO 80225. Information for ordering specific reports may be obtained from the Pennsylvania District Office at the address on the back of the title page or by phoning the Scientific and Technical Products Section at (717) 730-6940. Information on the availability of unpublished data or statistical analyses may be obtained from the District Information Specialist by telephone at (717) 730-6916 or by FAX at (717) 730-6997.

Water Data Report

Water resources data, Pennsylvania, water year 2000. Volume 3. Ohio and St. Lawrence River Basins

Introduction The Water Resources Division of the U.S. Geological Survey, in cooperation with State, municipal, and Federal agencies, collects a large amount of data pertaining to the water resources of Pennsylvania each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, these data are published annually in this report series entitled "Water Resources Data - Pennsylvania, Volumes 1, 2, and 3." Volume 1 contains data for the Delaware River Basin; Volume 2, the Susquehanna and Potomac River Basins; and Volume 3, the Ohio and St. Lawrence River Basins. This report, Volume 3, contains: (1) discharge records for 58 continuous-record streamflow-gaging stations, 5 partial-record stations, and 12 special study and miscellaneous streamflow sites; (2) elevation and contents records for 11 lakes and reservoirs; (3) water-quality records for 1 streamflow gaging station and 8 ungaged streamsites; and (4) water-level records for 15 ground-water network observation wells and. Additional water data collected at various sites not involved in the systematic data-collection program may also be presented. Publications similar to this report are published annually by the Geological Survey for all States. For the purpose of archiving, these official reports have an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as "U.S. Geological Survey Water-Data Report PA-00-3." These water-data reports, beginning with the 1971 water year, are for sale as paper copy or microfiche by the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161. The annual series of Water Data Reports for Pennsylvania began with the 1961 water-year report and contained only data relating to quantities of surface water. With the 1964 water year, a companion report (part 2) was introduced that contained only data relating to water quality. Beginning with the 1975 water year the report was changed to three volumes (by river basin), with each volume containing data on quantities of surface water, quality of surface and ground water, and ground-water levels. Prior to the introduction of this series and for several years concurrent with it, water-resources data for Pennsylvania were published in U.S. Geological Survey Water-Supply Papers. Data on stream discharge and stage, and on lake or reservoir contents and stage, through September 1960, were published annually under the title "Surface-Water Supply of the United States," which was released in numbered parts as determined by natural drainage basins. For the 1961-70 water years, these data were published in two 5-year reports. Data prior to 1961 are included in two reports: "Compilation of Records of Surface Waters of the United States through 1950," and "Compilation of Records of Surface Waters of the United States, October 1950 to September 1960." Data for Pennsylvania are published in Parts 1, 3, and 4. Data on chemical quality, temperature, and suspended sediment for the 1941-70 water years were published annually under the title "Quality of Surface Waters of the United States," and ground-water levels for the 1935-74 water years were published annually under the title "Ground-Water Levels in the United States." The above mentioned Water-Supply Papers may be consulted in the libraries of the principal cities of the United States and may be purchased from the U.S. Geological Survey, Information Services, Box 25286, Denver, CO 80225. Information for ordering specific reports may be obtained from the Pennsylvania District Office at the address on the back of the title page or by phoning the Scientific and Technical Products Section at (717) 730-6940. Information on the availability of unpublished data or statistical analyses may be obtained from the District Information Specialist by telephone at (717) 730-6916 or by FAX at (717) 730-6997.

Water Data Report

Water Resources Data, Pennsylvania, Water Year 2001, Volume 2. Susquehanna and Potomac River Basins

Introduction The Water Resources Division of the U.S. Geological Survey, in cooperation with State, municipal, and Federal agencies, collects a large amount of data pertaining to the water resources of Pennsylvania each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, these data are published annually in this report series entitled "Water Resources Data - Pennsylvania, Volumes 1, 2, and 3." Volume 1 contains data for the Delaware River Basin; Volume 2, the Susquehanna and Potomac River Basins; and Volume 3, the Ohio and St. Lawrence River Basins. This report, Volume 2, contains: (1) discharge records for 83 continuous-record streamflow-gaging stations, 15 partial-record stations, and 24 special study and miscellaneous streamflow sites; (2) elevation and contents records for 12 lakes and reservoirs; (3) water-quality records for 9 streamflow gaging stations and 73 partial-record and project stations; and (4) water-level records for 36 ground-water network observation wells and water-quality analyses of ground water from 8 wells; (5) water-quality analyses at 123 special study ground-water wells; and, (6) miscellaneous water-level measurements at 80 special study ground-water wells. Additional water data collected at various sites not involved in the systematic data-collection program may also be presented. Publications similar to this report are published annually by the Geological Survey for all States. For the purpose of archiving, these official reports have an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as "U.S. Geological Survey Water-Data Report PA-01-2." These water-data reports, beginning with the 1971 water year, are for sale as paper copy or microfiche by the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161. The annual series of Water Data Reports for Pennsylvania began with the 1961 water-year report and contained only data relating to quantities of surface water. With the 1964 water year, a companion report (part 2) was introduced that contained only data relating to water quality. Beginning with the 1975 water year the report was changed to three volumes (by river basin), with each volume containing data on quantities of surface water, quality of surface and ground water, and ground-water levels. Prior to the introduction of this series and for several years concurrent with it, water-resources data for Pennsylvania were published in U.S. Geological Survey Water-Supply Papers. Data on stream discharge and stage, and on lake or reservoir contents and stage, through September 1960, were published annually under the title "Surface-Water Supply of the United States," which was released in numbered parts as determined by natural drainage basins. For the 1961-70 water years, these data were published in two 5-year reports. Data prior to 1961 are included in two reports: "Compilation of Records of Surface Waters of the United States through 1950," and "Compilation of Records of Surface Waters of the United States, October 1950 to September 1960." Data for Pennsylvania are published in Parts 1, 3, and 4. Data on chemical quality, temperature, and suspended sediment for the 1941-70 water years were published annually under the title "Quality of Surface Waters of the United States," and ground-water levels for the 1935-74 water years were published annually under the title "Ground-Water Levels in the United States." The above mentioned Water-Supply Papers may be consulted in the libraries of the principal cities of the United States and may be purchased from the U.S. Geological Survey, Information Services, Box 25286, Denver, CO 80225. Information for ordering specific reports may be obtained from the Pennsylvania District Office at the address on the back of the title page or by phoning the Scientific and Technical Products Section at (717) 730-6940. Information on the availability of unpublished data or statistical analyses may be obtained from the District Information Specialist by telephone at (717) 730-6916 or by FAX at (717) 730-6997.

Water Data Report

Sensitivity of water resources in the Delaware River basin to climate variability and change

Because of the greenhouse effect, projected increases in atmospheric carbon dioxide levels might cause global warming, which in turn could result in changes in precipitation patterns and evapotranspiration and in increases in sea level. This report describes the greenhouse effect; discusses the problems and uncertainties associated with the detection, prediction, and effects of climate change; and presents the results of sensitivity analyses of how climate change might affect water resources in the Delaware River basin. Sensitivity analyses suggest that potentially serious shortfalls of certain water resources in the basin could result if some scenarios for climate change come true . The results of model simulations of the basin streamflow demonstrate the difficulty in distinguishing the effects that climate change versus natural climate variability have on streamflow and water supply . The future direction of basin changes in most water resources, furthermore, cannot be precisely determined because of uncertainty in current projections of regional temperature and precipitation . This large uncertainty indicates that, for resource planning, information defining the sensitivities of water resources to a range of climate change is most relevant . The sensitivity analyses could be useful in developing contingency plans for evaluating and responding to changes, should they occur.

Water Supply Paper

The role of paleoecology in restoration and resource management—The past as a guide to future decision-making: Review and example from the Greater Everglades Ecosystem, U.S.A

Resource managers around the world are challenged to develop feasible plans for sustainable conservation and/or restoration of the lands, waters, and wildlife they administer—a challenge made greater by anticipated climate change and associated effects over the next century. Increasingly, paleoecologic and geologic archives are being used to extend the period of record of observed data and provide information on centennial to millennial scale responses to long-term drivers of ecosystem change. The development of paleoecology from an emerging field investigating past environments to a highly relevant applied science is reviewed and general examples of the application of paleoecologic research to resource management questions in diverse habitats and regions are provided. Specific examples of the application of paleoecologic research to the restoration of the Greater Everglades Ecosystem of south Florida (U.S.A) are presented. Conducting valuable scientific research that would benefit resource management decisions, however, is not enough. Scientists and resource managers need to be engaged in collaborative discussions from the beginning of the research process to ensure that management questions are being addressed and that the science reaches the people who will benefit from the information. Paleoecology and related disciplines provide an understanding of how ecosystems and individual species function and change over time in response to both natural and anthropogenic drivers. Information on pre-anthropogenic baseline conditions is provided by paleoecologic research, but it is the detection of long-term trends and cycles that allow resource managers to set realistic goals and targets by moving away from the fixed-point baseline concept to one of dynamic landscapes that anticipates and incorporates an expectation of change into decision-making.

Florida

A novel method for conducting a geoenvironmental assessment of undiscovered ISR-amenable uranium Resources: Proof-of-concept in the Texas Coastal Plain

A geoenvironmental assessment methodology was developed to estimate waste quantities and disturbances that could be associated with the extraction of undiscovered uranium resources and identify areas on the landscape where uranium and other constituents of potential concern (COPCs) that may co-occur with uranium deposits in this region are likely to persist, if introduced into the environment. Prior to this work, a method was lacking to quantitively assess the environmental aspects associated with potential development of undiscovered uranium resources at a scale of a uranium resource assessment. The mining method of in situ recovery (ISR) was historically used to extract uranium from deposits in the Goliad Sand of the Texas Coastal Plain. For this reason, the study’s methodology projected the following types of wastes and disturbances commonly associated with ISR based on historical ISR mining records: the mine area, affected aquifer volume, mine pore volume, water pumped and disposed during uranium extraction and restoration, and radon emissions. Within the tract permissive for the occurrence of undiscovered uranium resources, maps and statistics of factors were derived that indicate the potential contaminant pathways. The percentage of days meeting the criteria for air stagnation indicate the potential for radon accumulation; the geochemical mobility of COPCs in groundwater in combination with effective recharge indicates the potential for infiltration of surface-derived COPCs; the geochemical mobility of COPCs in groundwater combined with hydraulic conductivity indicates the propensity for transmitting fluids away from contaminated or mined aquifers; and finally, geochemical mobility of COPCs in surface water combined with the factor for climatic erosivity (R factor) indicates the potential for COPCs to persist in surface waters due to runoff. This work resulted in a new methodology that can be applied to any undiscovered mineral resource to better understand possible wastes and disturbances associated with extraction and identify areas on the landscape where COPCs are likely to persist.

Texas

Natural resource management confronts the growing scale and severity of ecosystem responses to drought and wildfire

Intensification of drought and wildfire associated with climate change has triggered widespread ecosystem stress and transformation. Natural resource managers are on the frontline of these changes, yet their perspectives on whether management actions match the scale and align with the severity of ecosystem responses to improve outcomes are not well understood. To provide new insight, a new conceptual framework that linked scale and severity was tested by conducting interviews and surveys of staff associated with natural resource management on the Colorado Plateau in the southwestern United States (U.S.), which contains the highest concentration of public lands in the contiguous U.S. Results indicate that drought was experienced more frequently than wildfire, and both stressors were happening at large scales and moderate to abrupt timeframes with a high degree of impact to ecosystems. Ecosystem responses were perceived to increase in severity under future climate change with limited capacity to recover, and a majority of resource managers expressed that they had low control to shape these trajectories. Although management strategies to address drought and wildfire were well recognized, adaptation-specific actions remained unclear or had limited financial and staffing resources to support implementation. Additional effort could help close a growing misalignment between management actions and natural resource responses, including effective science communication, refined information tailored to meet adaptation goals at management-relevant spatiotemporal scales, and opportunities for adaptive management that can proactively address intensification of drought and wildfire.

Ecology and Society

Historical changes in the major fish resources of the Great Lakes

My purpose here is to review historic changes in the major fish resources of the five Great Lakes, and to identify the cause or causes for those changes. In some instances it will be clear that intensive fishing was the primary cause of change; in other instances it will be nearly as clear that predation by the sea lamprey played a significant if not dominant role in change; and in still others it will be clear (or at least circumstantial) that exotic species other than the sea lamprey have been implicated. The exotics that have invaded or been accidentally or purposefully released into the Great Lakes system have not only adversely affected indigenous fishes, but some have developed into new and valuable resources. However, when it comes to degradation of water quality and of critical habitat, the linkages to changes in fish populations are neither clear-cut nor quantifiable — their impacts were generally far more subtle and difficult to detect, but not necessarily of less importance. Inasmuch as a comprehensive review of all changes in fishery resources, water quality, and habitat conditions in the Great Lakes would be encyclopedic, I confine discussion here to prime examples related to the most historically important fish resources. One of the values of the approach used in this manuscript is the collation in a single-source document of the conclusions reached by many scientists on reasons for changes in the fish resources across the Great Lakes basin.

Book chapter

Prioritizing High-Temperature Geothermal Resources in Utah

The Utah Geological Survey and the Utah Energy Office recently released geothermal resource information for Utah as a "digital atlas." We are now expanding this project to include economic analyses of selected geothermal sites and previously unavailable resource information. The enhancements to the digital atlas will include new resource, demographic, regulatory, economic, and other information to allow analyses of economic factors for comparing and ranking geothermal resource sites in Utah for potential electric power development. New resource information includes temperature gradient and fluid chemistry data, which was previously proprietary. Economic analyses are based upon a project evaluation model to assess capital and operating expenses for a variety of geothermal powerplant configuration scenarios. A review of legal and institutional issues regarding geothermal development coupled with water development will also be included.

Conference Paper

The United Nations framework classification for fossil energy and mineral reserves and resources 2009

Effective resource management in a globalizing economy requires accurate assessments of fossil energy and minerals resources. The recoverable quantities must be described and categorized in a manner that is consistent with scientific and social/economic information describing the economy as well as with the information describing the projects to recover them. A number of different standards have evolved over time in response to various professional needs Under a mandate given by the United Nations Economic and Social Council, the United Nations Economic Commission for Europe (UNECE) has cooperated with Governments, regulatory agencies, industry, international organizations, and professional organizations (including Committee for Mineral Reserves International Reporting Standards (CRIRSCO), the Society of Petroleum Engineers (SPE), the American Association of Petroleum Geologists (AAPG), and the Society of Petroleum Evaluation Engineers (SPEE)), as well as with outstanding experts, to define a global classification for extractive activities (including oil, gas, heavy oil and bitumen extraction) that reflects the principal concerns of existing petroleum and mineral classifications. The United Nations Framework Classification for Fossil Energy and Mineral Reserves and Resources-2009 (UNFC-2009) aims to serve the following four principal needs: 1. The needs in international energy and mineral studies to formulate robust and long-sighted policies. 2. The needs of governments in managing their resources accordingly, allowing market prices to be transferred to the wellhead with as little loss as possible. 3. The industries' needs for information while deploying technology, management and finance to secure energy supplies and capture value efficiently within the established frameworks to serve its host countries, shareholders and stakeholders. 4. The financial community's need for information to allocate capital appropriately, providing reduced costs and improved long-sightedness through the application of lower risk-compensated discount factors. The projects are categorised with respect to economic and social viability, project feasibility and maturity and uncertainty with respect to the quantities addressed. The categorisation of projects rather than of accumulations provides coherence with other critical management information such as production, cash flows, value and demand for various input factors. This key aspect of UNFC-2009 reflects the critical relationship between the quantities that can be recovered economically and the recovery processes (projects) that must be implemented to achieve those recoveries. It facilitates the recognition of potential wastage of resources through flaring or inefficient recovery processes and therefore also the potential for improvement. Copyright 2011, Society of Petroleum Engineers.

Conference Paper

Geology and sequence stratigraphy of undiscovered oil and gas resources in conventional and continuous petroleum systems in the Upper Cretaceous Eagle Ford Group and related strata, U.S. Gulf Coast Region

The U.S. Geological Survey (USGS) recently assessed the technically recoverable undiscovered oil and gas onshore and in State waters of the Gulf Coast region of the United States. The USGS defined three assessment units (AUs) with potential undiscovered conventional and continuous oil and gas resources in Upper Cretaceous (Cenomanian to Turonian) strata of the Eagle Ford Group and correlative rocks. The assessment is based on geologic elements of a total petroleum system, including hydrocarbon source rocks (source rock maturation, hydrocarbon generation and migration), reservoir rocks (sequence stratigraphy and petrophysical properties), and traps (formation, timing, and seals). Conventional oil and gas undiscovered resources are in updip sandstone reservoirs in the Upper Cretaceous Tuscaloosa and Woodbine Formations (or Groups) in Louisiana and Texas, respectively, whereas continuous oil and continuous gas undiscovered resources reside in the middip and downdip Upper Cretaceous Eagle Ford Shale in Texas and the Tuscaloosa marine shale in Louisiana. Conventional resources in the Tuscaloosa and Woodbine are included in the Eagle Ford Updip Sandstone Oil and Gas AU, in an area where the Eagle Ford Shale and Tuscaloosa marine shale display vitrinite reflectance (Ro) values less than 0.6%. The continuous Eagle Ford Shale Oil AU lies generally south of the conventional AU, is primarily updip of the Lower Cretaceous shelf edge, and is defined by thermal maturity values within shales of the Eagle Ford and Tuscaloosa that range from 0.6 to 1.2% Ro. Similarly, the Eagle Ford Shale Gas AU is defined downdip of the shelf edge where source rocks have Ro values greater than 1.2%. For undiscovered oil and gas resources, the USGS assessed means of: 1) 141 million barrels of oil (MMBO), 502 billion cubic feet of natural gas (BCFG), and 4 million barrels of natural gas liquids (MMBNGL) in the Eagle Ford Updip Sandstone Oil and Gas AU; 2) 853 MMBO, 1707 BCFG, and 34 MMBNGL in the Eagle Ford Shale Oil AU; and 3) 50,219 BCFG and 2009 MMBNGL in the Eagle Ford Shale Gas AU.

Louisiana;Texas

Landscape ecology: a concept for protecting park resources

The Southwest Region has been supporting Resource Basic Inventory (RBI) efforts to establish baseline data for comparisons with long-term monitoring results to be conducted in the future. This “pulse taking” is a part of the Servicewide initiative being fostered so that resource managers, scientists, and park managers will be able to track the health of park resources by determining changes and trends. The RBI work is being linked with the development of Geographic Information Systems (GIS) at Bandelier, Big Thicket, Big Bend, Padre Island, and Guadalupe Mountains. Many of the parks in the southwest Region have only partially completed RBIs. This informational shortcoming is a pervasive threat to the parks because without detailed knowledge of the parks’ respective resources the Service cannot protect them adequately. To overcome this deficiency, the SWRO’s Division of Natural Resources Management and Science has fostered at Bandelier a pilot research effort, which started in FY ’87 and utilizes a landscape ecology paradigm. This concept links the RBI, GIS, and research activities in a park to present an overall picture of the park in its regional ecosystem setting. The flowchart diagrams this project’s concept. The results have been encouraging. A final report was recently completed (Allen 1989). This concept may now be applied to other Southwest Region parks.

Park Science

Recent geophysical and geological research in Antarctica related to the assessment of petroleum resources and potential environmental hazards to their development

During the 6-year negotiation of and adoption of the Convention on the Regulation of Antarctic Mineral Resources Activities on June 2, 1988, various countries have increased their attention to the possibility of exploitation of Antarctica's petroleum resources, which are covered by this treaty. However, there are no known petroleum resources in Antarctica, and scientific information is lacking to adequately assess any undiscovered resources or the possible environmental hazards to their development. Scientific research carried out in Antarctica since the International Geophysical Year (1957-1958) has provided a great deal of information on the geological framework of this ice-covered continent and its margin and has found general indications of the types of hazards that must be considered. Antarctica covers a vast area, and likely supergiant oil fields of the type to be exploited would be tiny (e.g., a few tens of kilometers across) in comparison. Any petroleum resources located in Antarctica will be found by applying the knowledge, techniques, and experience gained developing oil fields in other parts of the world and would, therefore, be other examples of general cases; in contrast, the Antarctic environment and its associated hazards must be considered unique.

Book chapter

Spring resource phenology and timing of songbird migration across the Gulf of Mexico

Migratory songbirds are advancing their arrival to breeding areas in response to climatic warming at temperate latitudes. Less is understood about the impacts of climate changes outside the breeding period. Every spring, millions of migrating songbirds that overwinter in the Caribbean and Central and South America stop to rest and refuel in the first available habitats after crossing the Gulf of Mexico. We used capture data from a long-term banding station (20 years: 1993 to 2012) located on the northern coast of the Gulf to assess the passage timing of 17 species making northward migrations into eastern North America. We further assessed spring resource phenology as measured by normalized difference vegetation index (NDVI) on nonbreeding ranges and en route. We tested the hypotheses that spring passage timing has advanced during the past two decades and that annual variability in passage timing into eastern North America is related to spring resource phenology on stationary nonbreeding ranges and during passage south of the Gulf. Further, we assessed whether annual variability in resource phenology south of the Gulf was a good indicator of the conditions that migrants encountered upon first landfall in eastern North America. We found no trend in migration timing for species that migrate from South America and annual variability in their passage timing was unrelated to environmental conditions in nonbreeding ranges or en route. Species that migrate from Central America and the Caribbean delayed arrival by 2 to 3 days over the 20-year period and arrived later during years when conditions were dryer in nonbreeding ranges and passage areas south of the Gulf. Further, year to year variability in spring resource phenology in nonbreeding ranges and passage areas south of the Gulf were not good indicators of resource phenology upon arrival in eastern North America. Therefore, despite the fact that many migrant species have been arriving increasingly earlier to breeding grounds, the passage timing of 17 species into eastern North America has either not changed or is slightly later, due to drying spring conditions in Central America and the Caribbean. Our results suggest that Nearctic–Neotropical migratory birds adjust the rate of migration primarily within eastern North America and, in light of warmer temperatures in the temperate zone and earlier arrival timing to breeding ranges, species that overwinter in Central America and the Caribbean may be increasing the speed of migration within eastern North America.

Studies in Avian Biology

Ground-water resources in the tri-state region adjacent to the Lower Delaware River

The purpose of this report is to appraise and evaluate the groundwater resources of a tri-state region adjacent to the lower Delaware River that is centered around Philadelphia, Pa., and Camden, N. J., and includes Wilmington, Del., and Trenton, N.J. Specifically, the region includes New Castle County, Del.; Burlington, Camden, Gloucester, Mercer, and Salem Counties in New Jersey; and Bucks, Chester, Delaware, Montgomery, and Philadelphia Counties in Pennsylvania. The peculiar advantages of ground water, such as its availability in many places without the necessity for expensive pipelines and its relatively uniform temperature and quality, make it an especially valuable resource in an industrial area. Large, readily available supplies of good, fresh water have contributed substantially to the recent rapid industrial growth of the lower Delaware River basin and will be vital to its continued prosperity. The major part of these supplies is drawn from the streams passing through the region, but very large quantities of ground water also are used. The region is divided almost equally by the Fall Line, which extends in a southwesterly direction along the general course of the Delaware River from Trenton, N.J., to Wilmington, Del., and beyond. Northwest of the Fall Line is a region of consolidated rocks in which ground water occurs mainly in cracks, crevices, and openings created or enlarged by weathering. The capacity of the various geologic formations to yield water depends largely upon the degree to which they have been fractured and weathered. The yield of individual wells in this part of the region is generally small to moderate and not readily predictable. Ground water in this part of the region is generally low in dissolved minerals and suitable for many uses without treatment. Southeast of the Fall Line lie the unconsolidated rocks of the Coastal Plain. Ground water occurs in these rocks largely in the pore spaces between the individual mineral grains. The major formations and the principal aquifers are rather uniform in their water-bearing characteristics over large areas. The yield of individual wells is moderate to very large and may be predicted with a reasonable degree of assurance. Sufficient quantities of ground water are available in most places for all ordinary purposes. The chemical quality of the ground water from the Coastal Plain aquifers is generally acceptable for most uses, but objectionable quantities of iron or other minerals are found in some places, and some waters have a low pH and are corrosive. More than 40 distinct geologic formations occur in the region. They range in age from Precambrian to Recent. Nearly all will yield some water to wells. However, only about a dozen yield water freely enough to be considered major aquifers. Of these, the sands of the Raritan and Magothy formations have been developed most intensively, and the Cohansey sand appears to have the greatest capacity for additional development. The present withdrawal of ground water in the region is estimated to average more than 200 mgd, of which more than half is drawn from the aquifers in the Raritan and Magothy formations. It is estimated that additional supplies of ground water, aggregating more than 1 billion gallons a day, can be developed within the region. Furthermore, substantial additional quantities can be developed outside the region for use within it if the need should ever arise. Induced recharge from the Delaware River supplies a substantial portion of the total water drawn from the Raritan and Magothy formations. In some areas, the quality of the water from these aquifers is approaching that of the river. Increased withdrawals of water from wells along the river will tend to increase induced recharge. Thus, the maintenance of a good quality of water in the river, which is desirable for many other reasons, is imperative if the quality of the ground-water supply is to be maintained. The proposed deepening of the Delaware River channel from Philadelphia to Trenton will greatly increase the opportunity for the interchange of water between the river and the adjacent aquifers. Whether this will be beneficial or detrimental to the ground-water supplies will depend upon the quality of the water in that reach of the river. If an acceptable quality of river water is maintained, the groundwater resources of the region will be augmented. If salt water from the ocean or excessive contamination from other sources should render the river water undesirable as a source of recharge, actual and potential ground-water supplies aggregating about 250 mgd would be endangered. The danger of salt-water encroachment into the aquifers normally yielding fresh water may limit the optimum yield of some of the most important aquifers in the region. Encroachment may come either from salt water in the surface-water bodies of the region or from parts of the aquifers, normally containing salt water. The protection of ground-water supplies against salt-water encroachment can be maintained only by constant vigilance, careful distribution of the pumping from the aquifers, regular sampling of outpost wells in exposed localities, and adjustment of rates of pumping in the light of changing conditions. The maximum beneficial utilization of the ground-water resources cannot be accomplished in haphazard fashion. It must be planned and controlled on the basis of sound, current information about the hydrology of the various aquifers. Continued and, in some areas, intensified investigations of the ground-water resources of the region should form the basis for such planning and control.

New Jersey, Pennsylvania, Delaware

Potential shale-oil resources of a stratigraphic sequence above the Mahogany Zone, Green River Formation, Piceance Creek Basin, Colorado

In the southern part of the Piceance Creek basin the upper part of the Green River Formation above the Mahogany zone contains beds of rich oil shale which may be economically recoverable by a surface-mining operation. Four units within this sequence were evaluated for thickness, distribution, oil yield, and potential shale-oil resources. In the area appraised, total estimated resources of 128.5 billion bbl of oil are contained within the sequence. It is thickest in T. 3 S., R. 96 W., where 354 feet of oil shale yields an average of 14 gal of oil per ton, with a total resource of 9.0 billion bbl. It is richest in T. 5 S., R. 96 W., where 250 feet of oil shale yields an average of 19 gal of oil per ton, with a total resource of 6.5 billion bbl. Resources are tabulated for four units of the sequence.

Colorado, Utah, Wyoming

The water resources of southeast Iowa

Water is vital in the lives of the people and the economy of any area. In order to utilize this natural resource in the most efficient and beneficial manner, a basic knowledge and understanding of its sources and the occurrence and potential of each source must be gained. To provide this knowledge, the Water Resources Division of the U.S. Geological Survey in cooperation with the Iowa Geological Survey compiled this atlas describing the water resources available for development in an 11-county area in southeast Iowa. The report contains information on the availability, quality, and utilization of water from all known sources and the future demands upon the water resources in southeast Iowa. The information is presented to aid water users and other persons searching for and evaluating sources of water in a particular place, and planners and water managers who must consider water resources on a regional basis.

Iowa

Water resources of east-central Iowa

Water is vital in the lives of the people and the economy of any area. To utilize this natural resource in the most efficient and beneficial manner, a basic knowledge and understanding of its sources and the occurrence and potential of each source must be gained. To provide this knowledge, the Water Resources Division of the U.S. Geological Survey in cooperation with the Iowa Geological Survey compiled this atlas describing the water resources available for development in an 12-county area in east-central Iowa. The report contains information on the availability, quality, and utilization of water from all known sources and the future demands upon the water resources in east-central Iowa. The information is presented to aid water users and other persons searching for and evaluating sources of water in a particular place, and planners and water managers who must consider water resources on a regional basis.

Iowa