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USGS1948

The volcano letter: A weekly news leaflet of the Hawaiian Volcano Research Association - 1948

The Volcano Letter was an informal publication issued at irregular intervals by the Hawaiian Volcano Observatory (HVO) during the years 1925 to 1955. Individual issues contain information on volcanic activity, volcano research, and volcano monitoring in Hawaii. Information on volcanic activity at other locations is also occasionally included. The Volcano Letter was published by HVO through multiple changes in administration, including the Hawaiian Volcano Research Association (1925 to 1932), the U.S. Geological Survey (1932 to 1935), the Department of the Interior (1935 to 1938), and the University of Hawai‘i (1938 to 1955). Issues 1-262 were published weekly from January 1, 1925, to January 2, 1930, and consisted of a single page of text. Issues 263-384, also published weekly, from January 9, 1930, to May 5, 1932, were generally longer—four pages— and provided more detail on volcanic activity, including photographs, maps, and plots. Weekly issues 385-387, published May 12-26, 1932, were a single page of text due to budget reductions brought on by the Great Depression. Budget restrictions reduced the publishing frequency to monthly for issues 388-428, covering the period of June 1932 to October 1935; these issues were generally shorter, 1-2 pages, and sometimes featured figures. From November 1935 to July 1938, issues 429-461 remained monthly but increased in length (generally eight pages) and featured figures frequently. Issues 462-530, published over the period of August 1938 to December 1955, varied in length from 2-15 pages, but were published quarterly, rather than monthly. Six of the Volcano Letters are misnumbered: Jan. 21, 1926 number is 55 though it should 56 July 29, 1926 number is 82 though it should be 83 Feb. 16, 1928 number is 161 though it should be 164 May 31, 1928 number is 197 though it should be 179 Nov. 29, 1928 number is 204 though it should be 205

Hawaii↗
USGS1949

The volcano letter: A weekly news leaflet of the Hawaiian Volcano Research Association - 1949

The Volcano Letter was an informal publication issued at irregular intervals by the Hawaiian Volcano Observatory (HVO) during the years 1925 to 1955. Individual issues contain information on volcanic activity, volcano research, and volcano monitoring in Hawaii. Information on volcanic activity at other locations is also occasionally included. The Volcano Letter was published by HVO through multiple changes in administration, including the Hawaiian Volcano Research Association (1925 to 1932), the U.S. Geological Survey (1932 to 1935), the Department of the Interior (1935 to 1938), and the University of Hawai‘i (1938 to 1955). Issues 1-262 were published weekly from January 1, 1925, to January 2, 1930, and consisted of a single page of text. Issues 263-384, also published weekly, from January 9, 1930, to May 5, 1932, were generally longer—four pages— and provided more detail on volcanic activity, including photographs, maps, and plots. Weekly issues 385-387, published May 12-26, 1932, were a single page of text due to budget reductions brought on by the Great Depression. Budget restrictions reduced the publishing frequency to monthly for issues 388-428, covering the period of June 1932 to October 1935; these issues were generally shorter, 1-2 pages, and sometimes featured figures. From November 1935 to July 1938, issues 429-461 remained monthly but increased in length (generally eight pages) and featured figures frequently. Issues 462-530, published over the period of August 1938 to December 1955, varied in length from 2-15 pages, but were published quarterly, rather than monthly. Six of the Volcano Letters are misnumbered: Jan. 21, 1926 number is 55 though it should 56 July 29, 1926 number is 82 though it should be 83 Feb. 16, 1928 number is 161 though it should be 164 May 31, 1928 number is 197 though it should be 179 Nov. 29, 1928 number is 204 though it should be 205

Hawaii↗
USGS1950

The volcano letter: A weekly news leaflet of the Hawaiian Volcano Research Association - 1950

The Volcano Letter was an informal publication issued at irregular intervals by the Hawaiian Volcano Observatory (HVO) during the years 1925 to 1955. Individual issues contain information on volcanic activity, volcano research, and volcano monitoring in Hawaii. Information on volcanic activity at other locations is also occasionally included. The Volcano Letter was published by HVO through multiple changes in administration, including the Hawaiian Volcano Research Association (1925 to 1932), the U.S. Geological Survey (1932 to 1935), the Department of the Interior (1935 to 1938), and the University of Hawai‘i (1938 to 1955). Issues 1-262 were published weekly from January 1, 1925, to January 2, 1930, and consisted of a single page of text. Issues 263-384, also published weekly, from January 9, 1930, to May 5, 1932, were generally longer—four pages— and provided more detail on volcanic activity, including photographs, maps, and plots. Weekly issues 385-387, published May 12-26, 1932, were a single page of text due to budget reductions brought on by the Great Depression. Budget restrictions reduced the publishing frequency to monthly for issues 388-428, covering the period of June 1932 to October 1935; these issues were generally shorter, 1-2 pages, and sometimes featured figures. From November 1935 to July 1938, issues 429-461 remained monthly but increased in length (generally eight pages) and featured figures frequently. Issues 462-530, published over the period of August 1938 to December 1955, varied in length from 2-15 pages, but were published quarterly, rather than monthly. Six of the Volcano Letters are misnumbered: Jan. 21, 1926 number is 55 though it should 56 July 29, 1926 number is 82 though it should be 83 Feb. 16, 1928 number is 161 though it should be 164 May 31, 1928 number is 197 though it should be 179 Nov. 29, 1928 number is 204 though it should be 205

Hawaii↗
USGS1951

The volcano letter: A weekly news leaflet of the Hawaiian Volcano Research Association - 1951

The Volcano Letter was an informal publication issued at irregular intervals by the Hawaiian Volcano Observatory (HVO) during the years 1925 to 1955. Individual issues contain information on volcanic activity, volcano research, and volcano monitoring in Hawaii. Information on volcanic activity at other locations is also occasionally included. The Volcano Letter was published by HVO through multiple changes in administration, including the Hawaiian Volcano Research Association (1925 to 1932), the U.S. Geological Survey (1932 to 1935), the Department of the Interior (1935 to 1938), and the University of Hawai‘i (1938 to 1955). Issues 1-262 were published weekly from January 1, 1925, to January 2, 1930, and consisted of a single page of text. Issues 263-384, also published weekly, from January 9, 1930, to May 5, 1932, were generally longer—four pages— and provided more detail on volcanic activity, including photographs, maps, and plots. Weekly issues 385-387, published May 12-26, 1932, were a single page of text due to budget reductions brought on by the Great Depression. Budget restrictions reduced the publishing frequency to monthly for issues 388-428, covering the period of June 1932 to October 1935; these issues were generally shorter, 1-2 pages, and sometimes featured figures. From November 1935 to July 1938, issues 429-461 remained monthly but increased in length (generally eight pages) and featured figures frequently. Issues 462-530, published over the period of August 1938 to December 1955, varied in length from 2-15 pages, but were published quarterly, rather than monthly. Six of the Volcano Letters are misnumbered: Jan. 21, 1926 number is 55 though it should 56 July 29, 1926 number is 82 though it should be 83 Feb. 16, 1928 number is 161 though it should be 164 May 31, 1928 number is 197 though it should be 179 Nov. 29, 1928 number is 204 though it should be 205

Hawaii↗
USGS1952

The volcano letter: A weekly news leaflet of the Hawaiian Volcano Research Association - 1952

The Volcano Letter was an informal publication issued at irregular intervals by the Hawaiian Volcano Observatory (HVO) during the years 1925 to 1955. Individual issues contain information on volcanic activity, volcano research, and volcano monitoring in Hawaii. Information on volcanic activity at other locations is also occasionally included. The Volcano Letter was published by HVO through multiple changes in administration, including the Hawaiian Volcano Research Association (1925 to 1932), the U.S. Geological Survey (1932 to 1935), the Department of the Interior (1935 to 1938), and the University of Hawai‘i (1938 to 1955). Issues 1-262 were published weekly from January 1, 1925, to January 2, 1930, and consisted of a single page of text. Issues 263-384, also published weekly, from January 9, 1930, to May 5, 1932, were generally longer—four pages— and provided more detail on volcanic activity, including photographs, maps, and plots. Weekly issues 385-387, published May 12-26, 1932, were a single page of text due to budget reductions brought on by the Great Depression. Budget restrictions reduced the publishing frequency to monthly for issues 388-428, covering the period of June 1932 to October 1935; these issues were generally shorter, 1-2 pages, and sometimes featured figures. From November 1935 to July 1938, issues 429-461 remained monthly but increased in length (generally eight pages) and featured figures frequently. Issues 462-530, published over the period of August 1938 to December 1955, varied in length from 2-15 pages, but were published quarterly, rather than monthly. Six of the Volcano Letters are misnumbered: Jan. 21, 1926 number is 55 though it should 56 July 29, 1926 number is 82 though it should be 83 Feb. 16, 1928 number is 161 though it should be 164 May 31, 1928 number is 197 though it should be 179 Nov. 29, 1928 number is 204 though it should be 205

Hawaii↗
USGS1953

The volcano letter: A weekly news leaflet of the Hawaiian Volcano Research Association - 1953

The Volcano Letter was an informal publication issued at irregular intervals by the Hawaiian Volcano Observatory (HVO) during the years 1925 to 1955. Individual issues contain information on volcanic activity, volcano research, and volcano monitoring in Hawaii. Information on volcanic activity at other locations is also occasionally included. The Volcano Letter was published by HVO through multiple changes in administration, including the Hawaiian Volcano Research Association (1925 to 1932), the U.S. Geological Survey (1932 to 1935), the Department of the Interior (1935 to 1938), and the University of Hawai‘i (1938 to 1955). Issues 1-262 were published weekly from January 1, 1925, to January 2, 1930, and consisted of a single page of text. Issues 263-384, also published weekly, from January 9, 1930, to May 5, 1932, were generally longer—four pages— and provided more detail on volcanic activity, including photographs, maps, and plots. Weekly issues 385-387, published May 12-26, 1932, were a single page of text due to budget reductions brought on by the Great Depression. Budget restrictions reduced the publishing frequency to monthly for issues 388-428, covering the period of June 1932 to October 1935; these issues were generally shorter, 1-2 pages, and sometimes featured figures. From November 1935 to July 1938, issues 429-461 remained monthly but increased in length (generally eight pages) and featured figures frequently. Issues 462-530, published over the period of August 1938 to December 1955, varied in length from 2-15 pages, but were published quarterly, rather than monthly. Six of the Volcano Letters are misnumbered: Jan. 21, 1926 number is 55 though it should 56 July 29, 1926 number is 82 though it should be 83 Feb. 16, 1928 number is 161 though it should be 164 May 31, 1928 number is 197 though it should be 179 Nov. 29, 1928 number is 204 though it should be 205

Hawaii↗
USGS1954

The volcano letter: A weekly news leaflet of the Hawaiian Volcano Research Association - 1954

The Volcano Letter was an informal publication issued at irregular intervals by the Hawaiian Volcano Observatory (HVO) during the years 1925 to 1955. Individual issues contain information on volcanic activity, volcano research, and volcano monitoring in Hawaii. Information on volcanic activity at other locations is also occasionally included. The Volcano Letter was published by HVO through multiple changes in administration, including the Hawaiian Volcano Research Association (1925 to 1932), the U.S. Geological Survey (1932 to 1935), the Department of the Interior (1935 to 1938), and the University of Hawai‘i (1938 to 1955). Issues 1-262 were published weekly from January 1, 1925, to January 2, 1930, and consisted of a single page of text. Issues 263-384, also published weekly, from January 9, 1930, to May 5, 1932, were generally longer—four pages— and provided more detail on volcanic activity, including photographs, maps, and plots. Weekly issues 385-387, published May 12-26, 1932, were a single page of text due to budget reductions brought on by the Great Depression. Budget restrictions reduced the publishing frequency to monthly for issues 388-428, covering the period of June 1932 to October 1935; these issues were generally shorter, 1-2 pages, and sometimes featured figures. From November 1935 to July 1938, issues 429-461 remained monthly but increased in length (generally eight pages) and featured figures frequently. Issues 462-530, published over the period of August 1938 to December 1955, varied in length from 2-15 pages, but were published quarterly, rather than monthly. Six of the Volcano Letters are misnumbered: Jan. 21, 1926 number is 55 though it should 56 July 29, 1926 number is 82 though it should be 83 Feb. 16, 1928 number is 161 though it should be 164 May 31, 1928 number is 197 though it should be 179 Nov. 29, 1928 number is 204 though it should be 205

Hawaii↗
USGS1955

The volcano letter: A weekly news leaflet of the Hawaiian Volcano Research Association - 1955

The Volcano Letter was an informal publication issued at irregular intervals by the Hawaiian Volcano Observatory (HVO) during the years 1925 to 1955. Individual issues contain information on volcanic activity, volcano research, and volcano monitoring in Hawaii. Information on volcanic activity at other locations is also occasionally included. The Volcano Letter was published by HVO through multiple changes in administration, including the Hawaiian Volcano Research Association (1925 to 1932), the U.S. Geological Survey (1932 to 1935), the Department of the Interior (1935 to 1938), and the University of Hawai‘i (1938 to 1955). Issues 1-262 were published weekly from January 1, 1925, to January 2, 1930, and consisted of a single page of text. Issues 263-384, also published weekly, from January 9, 1930, to May 5, 1932, were generally longer—four pages— and provided more detail on volcanic activity, including photographs, maps, and plots. Weekly issues 385-387, published May 12-26, 1932, were a single page of text due to budget reductions brought on by the Great Depression. Budget restrictions reduced the publishing frequency to monthly for issues 388-428, covering the period of June 1932 to October 1935; these issues were generally shorter, 1-2 pages, and sometimes featured figures. From November 1935 to July 1938, issues 429-461 remained monthly but increased in length (generally eight pages) and featured figures frequently. Issues 462-530, published over the period of August 1938 to December 1955, varied in length from 2-15 pages, but were published quarterly, rather than monthly. Six of the Volcano Letters are misnumbered: Jan. 21, 1926 number is 55 though it should 56 July 29, 1926 number is 82 though it should be 83 Feb. 16, 1928 number is 161 though it should be 164 May 31, 1928 number is 197 though it should be 179 Nov. 29, 1928 number is 204 though it should be 205

Hawaii↗
USGS2010

Reducing Uncertainty in the Distribution of Hydrogeologic Units within Volcanic Composite Units of Pahute Mesa Using High-Resolution 3-D Resistivity Methods, Nevada Test Site, Nevada

The U.S. Department of Energy (DOE) and the National Nuclear Security Administration (NNSA) at their Nevada Site Office (NSO) are addressing groundwater contamination resulting from historical underground nuclear testing through the Environmental Management program and, in particular, the Underground Test Area (UGTA) project. From 1951 to 1992, 828 underground nuclear tests were conducted at the Nevada Test Site (NTS) northwest of Las Vegas (DOE UGTA, 2003). Most of these tests were conducted hundreds of feet above the groundwater table; however, more than 200 of the tests were near, or within, the water table. This underground testing was limited to specific areas of the NTS including Pahute Mesa, Rainier Mesa/Shoshone Mountain, Frenchman Flat, and Yucca Flat. Volcanic composite units make up much of the area within the Pahute Mesa Corrective Action Unit (CAU) at the NTS, Nevada. The extent of many of these volcanic composite units extends throughout and south of the primary areas of past underground testing at Pahute and Rainier Mesas. As situated, these units likely influence the rate and direction of groundwater flow and radionuclide transport. Currently, these units are poorly resolved in terms of their hydrologic properties introducing large uncertainties into current CAU-scale flow and transport models. In 2007, the U.S. Geological Survey (USGS), in cooperation with DOE and NNSA-NSO acquired three-dimensional (3-D) tensor magnetotelluric data at the NTS in Area 20 of Pahute Mesa CAU. A total of 20 magnetotelluric recording stations were established at about 600-m spacing on a 3-D array and were tied to ER20-6 well and other nearby well control (fig. 1). The purpose of this survey was to determine if closely spaced 3-D resistivity measurements can be used to characterize the distribution of shallow (600- to 1,500-m-depth range) devitrified rhyolite lava-flow aquifers (LFA) and zeolitic tuff confining units (TCU) in areas of limited drill hole control on Pahute Mesa within the Calico Hills zeolitic volcanic composite unit (VCU), an important hydrostratigraphic unit in Area 20. The resistivity response was evaluated and compared with existing well data and hydrogeologic unit tops from the current Pahute Mesa framework model. In 2008, the USGS processed and inverted the magnetotelluric data into a 3-D resistivity model. We interpreted nine depth slices and four west-east profile cross sections of the 3-D resistivity inversion model. This report documents the geologic interpretation of the 3-D resistivity model. Expectations are that spatial variations in the electrical properties of the Calico Hills zeolitic VCU can be detected and mapped with 3-D resistivity, and that these changes correlate to differences in rock permeability. With regard to LFA and TCU, electrical resistivity and permeability are typically related. Tuff confining units will typically have low electrical resistivity and low permeability, whereas LFA will have higher electrical resistivity and zones of higher fracture-related permeability. If expectations are shown to be correct, the method can be utilized by the UGTA scientists to refine the hydrostratigraphic unit (HSU) framework in an effort to more accurately predict radionuclide transport away from test areas on Pahute and Rainier Mesas.

Nevada↗
USGS1992

Crystalline Silica Primer

Crystalline silica is the scientific name for a group of minerals composed of silicon and oxygen. The term crystalline refers to the fact that the oxygen and silicon atoms are arranged in a threedimensional repeating pattern. This group of minerals has shaped human history since the beginning of civilization. From the sand used for making glass to the piezoelectric quartz crystals used in advanced communication systems, crystalline silica has been a part of our technological development. Crystalline silica's pervasiveness in our technology is matched only by its abundance in nature. It's found in samples from every geologic era and from every location around the globe. Scientists have known for decades that prolonged and excessive exposure to crystalline silica dust in mining environments can cause silicosis, a noncancerous lung disease. During the 1980's, studies were conducted that suggested that crystalline silica also was a carcinogen. As a result of these findings, crystalline silica has been regulated under the Occupational Safety and Health Administration's (OSHA) Hazard Communication Standard (HCS). Under HCS, OSHAregulated businesses that use materials containing 0.1% or more crystalline silica must follow Federal guidelines concerning hazard communication and worker training. Although the HCS does not require that samples be analyzed for crystalline silica, mineral suppliers or OSHAregulated businesses may choose to do so if they wish to show that they are exempt from the requirements of HCS. Because crystalline silica is an extremely common mineral and the HCS will affect many mineral commodities, it is important then, that there be as clear an understanding as possible of what is and what is not crystalline silica, and where it is found and used, and how it is qualitatively and quantitatively identified. This primer is an attempt to accomplish this in as nontechnical a manner as possible. This primer will examine crystalline silica. Part I will describe, in nonscientific terms, what crystalline silica is and how we come in contact with it. Part II will discuss the regulatory decisions that have created new interest in this ancient and widespread substance and will present a nontechnical overview of the techniques used to measure crystalline silica. Because this primer is meant to be a starting point for anyone interested in learning more about crystalline silica, a list of selected readings and other resources is included. The detailed glossary, which defines many terms that are beyond the scope of this publication, is designed to help the reader move from this presentation to a more technical one, the inevitable next step.

Special Publication↗
USGS2008

Geologic map of the Fredonia 30' x 60' quadrangle, Mohave and Coconino counties, northern Arizona

This geologic map is the result of a cooperative effort of the U.S. Geological Survey, the National Park Service, the U.S. Forest Service, and the Bureau of Land Management (BLM) and the Kaibab-Paiute Tribe to provide a regional geologic database for resource management officials of all government and agencies, city municipalities, private enterprises, and individuals of this part of the Arizona Strip. The Arizona Strip is part of northwestern Arizona north of the Colorado River and bounded by the States of Nevada and Utah. Field work on the Kaibab-Paiute Indian Reservation was conducted from 2002 to 2005 with permission from the Kaibab-Paiute Tribal Government of that administration and permission was granted to publish a geologic map of 4 quadrangles online (Billingsley and others, 2004). The Kaibab-Paiute Tribal government of 2006 to 2008 requested that all geologic information within the Kaibab-Paiute Indian Reservation not be published as part of the Fredonia 30' x 60' quadrangle (this publication). For further information, contact the Kaibab-Paiute Tribal government at HC 65 Box 2, Fredonia, Arizona, 86022, telephone # (928) 643-7245. Visitors to the Kaibab-Paiute Indian Reservation are required to obtain a permit and permission for access from the Tribal Offices at the junction of State Highway 389 and the paved road leading to Pipe Spring National Monument. The Fredonia 30' x 60' quadrangle encompasses approximately 5,018 km2 (1,960 mi2) within Mohave and Coconino Counties, northern Arizona and is bounded by longitude 112 deg to 113 deg W., and latitude 36 deg 30' to 37 deg N. The map area lies within the southern Colorado Plateaus geologic province (herein Colorado Plateau). The map area is locally subdivided into seven physiographic parts: the Grand Canyon (Kanab Canyon and its tributaries), Kanab Plateau, Uinkaret Plateau, Kaibab Plateau, Paria Plateau, House Rock Valley, and Moccasin Mountains as defined by Billingsley and others, 1997, (fig. 1). Elevations range from 2,737 m (8,980 ft) just west of State Highway 67 on the Kaibab Plateau, southeast corner of the map area to about 927 m (3,040 ft) in Kanab Canyon, south-central edge of the map area.

Arizona↗
USGS2009

Land-cover change in the central irregular plains, 1973-2000

Spearheaded by the Geographic Analysis and Monitoring Program of the U.S. Geological Survey (USGS) in collaboration with the U.S. Environmental Protection Agency (EPA) and the National Aeronautics and Space Administration (NASA), the Land Cover Trends is a research project focused on understanding the rates, trends, causes, and consequences of contemporary United States land-use and land-cover change. Using the EPA Level III ecoregions as the geographic framework, scientists process geospatial data collected between 1973 and 2000 to characterize ecosystem responses to land-use changes. The 27-year study period was divided into five temporal periods: 1973-1980, 1980-1986, 1986-1992, 1992-2000 and 1973-2000. General land-cover classes for these periods were interpreted from Landsat Multispectral Scanner, Thematic Mapper, and Enhanced Thematic Mapper Plus imagery to categorize land-cover change and evaluate using a modified Anderson Land Use Land Cover Classification System for image interpretation. The rates of land-cover change are estimated using a stratified, random sampling of 10-kilometer (km) by 10-km blocks allocated within each ecoregion. For each sample block, satellite images are used to interpret land-cover change. Additionally, historical aerial photographs from similar timeframes and other ancillary data such as census statistics and published literature are used. The sample block data are then incorporated into statistical analyses to generate an overall change matrix for the ecoregion. These change statistics are applicable for different levels of scale, including total change for the individual sample blocks and change estimates for the entire ecoregion. The results illustrate that there is no single profile of land-cover change but instead point to geographic variability that results from land uses within ecoregions continuously adapting to various factors including environmental, technological, and socioeconomic.

Open-File Report↗
USGS2021

Storms and floods of July 30, 2016, and May 27, 2018, in Ellicott City, Howard County, Maryland

Introduction On July 30, 2016, and May 27, 2018, the downtown area of Ellicott City, Maryland (fig. 1), was severely flooded by intense, short-duration rainfall that resulted in loss of life; significant damage to buildings, roads, infrastructure; and hundreds of vehicles washed away. Precipitation from the 2016 event totaled 6.60 inches in 3 hours (National Oceanic and Atmospheric Administration, 2016). Precipitation from the 2018 storm totaled 6.56 inches in 3 hours (National Oceanic and Atmospheric Administration, 2018). In the aftermath of both storms, personnel from the U.S. Geological Survey (USGS) performed indirect discharge measurements to determine peak flow on the three streams that drain through the downtown area of Ellicott City and empty into the Patapsco River. High-water marks were flagged on selected reaches of three streams, Hudson Branch (station 01589017), Tiber Branch (station 01589019), and New Cut Branch (station 01589021) (fig. 2). Peak flows were computed using flow-through-culvert techniques with road overflow for Hudson Branch and slope-area techniques for Tiber Branch and New Cut Branch. This fact sheet describes the basin characteristics, hydrologic characteristics, and flood history of the Ellicott City, Maryland, area. The storms and flood characteristics for July 30, 2016, and May 27, 2018, are described. Peak discharges computed from the indirect discharge measurements for Hudson Branch, Tiber Branch, and New Cut Branch are presented for the storms and floods of July 30, 2016, and May 27, 2018. To provide historical perspective on these floods in Ellicott City, results from the indirect discharge measurement computations were compared to peak flows from 75 USGS streamgages and 6 miscellaneous sites in Maryland and Delaware that resulted from intense storms in August and September 1971 (Carpenter, 1974). The findings indicate that although the Ellicott City storms and floods from July 30, 2016, and May 27, 2018, are considered very rare in terms of their probability of occurrence, other storms have occurred in the Maryland and Delaware regions in the past that have produced comparable runoff characteristics relative to drainage-area magnitude.

Maryland↗
USGS2020

Ecological forecasting—21st century science for 21st century management

Natural resource managers are coping with rapid changes in both environmental conditions and ecosystems. Enabled by recent advances in data collection and assimilation, short-term ecological forecasting may be a powerful tool to help resource managers anticipate impending near-term changes in ecosystem conditions or dynamics. Managers may use the information in forecasts to minimize the adverse effects of ecological stressors and optimize the effectiveness of management actions. To explore the potential for ecological forecasting to enhance natural resource management, the U.S. Geological Survey (USGS) convened a workshop titled "Building Capacity for Applied Short-Term Ecological Forecasting" on May 29—31, 2019, with participants from several Federal agencies, including the Bureau of Land Management, the U.S. Fish and Wildlife Service, the National Park Service, and the National Oceanic and Atmospheric Administration as well as all mission areas within the USGS. Participants broadly agreed that short-term ecological forecasting—on the order of days to years into the future—has tremendous potential to improve the quality and timeliness of information available to guide resource management decisions. Participants considered how ecological forecasting could directly affect their agency missions and specified numerous critical tools for addressing natural resource management concerns in the 21st century that could be enhanced by ecological forecasting. Given this breadth of possible applications for forecast products, participants developed a repeatable framework for evaluating potential value of a forecast product for enhancing resource management. Applying that process to a large list of forecast ideas that were developed in a brainstorming session, participants identified a small set of promising forecast products that illustrate the value of ecological forecasting for informing resource management. Workshop outcomes also include insights about important likely obstacles and next steps. In particular, reliable production and delivery of operational ecological forecasts will require a sustained commitment by research agencies, in partnership with resource management agencies, to maintain and improve forecasting tools and capabilities.

Open-File Report↗
USGS1996

Reconnaissance of hydrologic monitoring sites and preliminary monitoring plan for the Vale, Oregon, geothermal area

The Bonneville Power Administration is working with private industry to develop a geothermal demonstration project in the Known Geothermal Resources Area (KGRA) near Vale, Oregon. Hydrologic monitoring in the area is planned in order to evaluate any impacts from the proposed development. The hydrology in and around the Vale KGRA is not well known. Additionally, little is known about the targeted geothermal reservoir and the nature of its connection to the shallow ground-water system. Given this uncertainty, a variety of features were selected to ensure adequate monitoring coverage. Wells and springs in and around the geothermal area were evaluated, and 19 were selected as potential monitoring sites. In selecting wells and springs for monitoring, particular emphasis was placed on those with a known or probable connection with the geothermal system because they would most likely be the first to show any effects from development. The selected features include thermal wells in the hot-spring area near the town of Vale and a hot spring south of the KGRA. Several warm wells (70 to 90 degrees Fahrenheit) near the KGRA were also selected because it is likely that the water produced from these wells includes a component of geothermal water. In order to identify any effects of development, it is necessary to have an understanding of natural and man-caused variations and trends prior to development. A quarterly measurement schedule is proposed to help characterize these variations and trends. It is anticipated that the proposed monitoring plan will be modified as exploration and development proceed and more is learned about the geothermal system.

Oregon↗
USGS2014

Sea-floor geology in northwestern Block Island Sound, Rhode Island

Multibeam-echosounder and sidescan-sonar data, collected by the National Oceanic and Atmospheric Administration in a 69-square-kilometer area of northwestern Block Island Sound, are used with sediment samples, and still and video photography of the sea floor, collected by the U.S. Geological Survey at 43 stations within this area, to interpret the sea-floor features and sedimentary environments. Features on the sea floor include boulders, sand waves, scour depressions, modern marine sediments, and trawl marks. Boulders, which are often several meters wide, are found in patches in the shallower depths and tend to be overgrown with sessile flora and fauna. They are lag deposits of winnowed glacial drift, and reflect high-energy environments characterized by processes associated with erosion and nondeposition. Sand waves and megaripples tend to have crests that either trend parallel to shore with 20- to 50-meter (m) wavelengths or trend perpendicular to shore with several-hundred-meter wavelengths. The sand waves reflect sediment transport directions perpendicular to shore by waves, and parallel to shore by tidal or wind-driven currents, respectively. Scour depressions, which are about 0.5 m lower than the surrounding sea floor, have floors of gravel and coarser sand than bounding modern marine sediments. These scour depressions, which are conspicuous in the sidescan-sonar data because of their more highly reflective coarser sediment floors, are likely formed by storm-generated, seaward-flowing currents and maintained by the turbulence in bottom currents caused by their coarse sediments. Areas of the sea floor with modern marine sediments tend to be relatively flat to current-rippled and sandy.

Rhode Island↗
USGS1983

Alternate data sources for soil surveys on rangeland

Soil information is an essential theme in a digital information base for land management and resource monitoring, but public land management agencies seldom have detailed soil maps available for all of the area under their administration. Most of these agencies conduct soil surveys on a scheduled basis, but escalating costs and declining budgets are reducing the number of surveys that can be scheduled. Digital elevation and satellite spectral data are available or are obtainable for all areas in the continental United States and may be used as an aid to produce soils data. A study was conducted in the Grass Creek Resource Area in north-central Wyoming to assess the utility of incorporating digital elevation and Landsat data into an information base for soil survey and to evaluate the usefulness of these data as an input to an order-three soil survey. Slope-interval maps were produced from digital elevation data and topographic maps of three 7.5-minute quadrangle areas. These slope-interval maps were then overlaid on orthophotoquadrangles and used to produce photo-interpreted physiographic maps. These physiographic maps were digitized into a data base and used with Landsat multispectral scanner data to produce tabular summaries that describe each map polygon in terms of physiographic unit, slope, aspect, elevation, area, and spectral values. A good relationship was found between the physiographic units and soil mapping units defined during a conventional soil survey, and between the Landsat spectral categories and existing vegetation communities. Field evaluations confirmed the feasibility of using this approach for producing physiographic maps as an aid for mapping soils and range sites. The project is a cooperative investigation of the Earth Resources Observation Systems Data Center of the U.S. Geological Survey, the Soil Conservation Service, and the Bureau of Land Management.

Open-File Report↗
USGS2007

Geologic Map of the Sif Mons Quadrangle (V-31), Venus

The Magellan spacecraft orbited Venus from August 10, 1990, until it plunged into the Venusian atmosphere on October 12, 1994. Magellan Mission objectives included (1) improving the knowledge of the geological processes, surface properties, and geologic history of Venus by analysis of surface radar characteristics, topography, and morphology and (2) improving the knowledge of the geophysics of Venus by analysis of Venusian gravity. The Sif Mons quadrangle of Venus includes lat 0? to 25? N. and long 330? to 0? E.; it covers an area of about 8.10 x 106 km2 (fig. 1). The data used to construct the geologic map were from the National Aeronautics and Space Administration (NASA) Magellan Mission. The area is also covered by Arecibo images, which were also consulted (Campbell and Campbell, 1990; Campbell and others, 1989). Data from the Soviet Venera orbiters do not cover this area. All of the SAR products were employed for geologic mapping. C1-MIDRs were used for general recognition of units and structures; F-MIDRs and F-MAPs were used for more specific examination of surface characteristics and structures. Where the highest resolution was required or some image processing was necessary to solve a particular mapping problem, the images were examined using the digital data on CD-ROMs. In cycle 1, the SAR incidence angles for images obtained for the Sif Mons quadrangle ranged from 44? to 46?; in cycle 3, they were between 25? and 26?. We use the term 'high backscatter' of a material unit to imply a rough surface texture at the wavelength scale used by Magellan SAR. Conversely, 'low backscatter' implies a smooth surface. In addition, altimetric, radiometric, and rms slope data were superposed on SAR images. Figure 2 shows altimetry data; figure 3 shows images of ancillary data for the quadrangle; and figure 4 shows backscatter coefficient for selected units. The interpretation of these data was discussed by Ford and others (1989, 1993). For corrected backscatter and numerical ancillary data see tables 1 and 2; these data allow comparison with units at different latitudes on the planet, where the visual appearance may differ because of a different incidence angle. Synthetic stereo images, produced by overlaying SAR images and altimetric data, were of great value in interpreting structures and stratigraphic relations.

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