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At least 1,207 records · Page 67Linked to original sources
USGS1980

New evidence for the age of the Quantico Formation of Virginia

A new fossil locality within the Quantico Formation of the Virginia Piedmont in Dale City, Virginia, about 40 km south of Washington, D.C., has yielded crinoids and a cephalopod that re-establishes an age younger than Cambrian for this formation. On the basis of regional considerations and the work of investigators in the early 1900s, an Ordovician age for the Quantico seems likely. Also, the Dale City pluton is not intrusive into the Quantico but is unconformable beneath it. Hence, the 560-m.y. zircon age for the Dale City pluton is no longer inconsistent with the temporal and stratigraphic relationships established for the stratigraphic units in the area. © 1980 Geological Society of America.

Virginia↗
USGS2014

Evaluation of the behavior and movement of adult summer steelhead in the lower Cowlitz River, Washington, following collection and release, 2013-2014

Summer steelhead ( Oncorhynchus mykiss ) produced by a hatchery on the lower Cowlitz River, Washington, support a popular sport fishery during June–September each year. Many of these fish return to the Cowlitz Salmon Hatchery and are held until they are spawned in December. In the past, fishery managers have released some of the steelhead that return to the hatchery at downstream release sites (hereafter referred to as “recycled steelhead”) to increase angling opportunity. The recycling of summer steelhead is a potential use of hatchery fish that can benefit anglers in the lower Cowlitz River, provided these fish are harvested or return to the hatchery. However, recycled steelhead that are not removed from the river could compete against or spawn with wild winter steelhead, which would be a negative consequence of recycling. The Washington Department of Fish and Wildlife (WDFW) conducted an evaluation during 1998 and recycled 632 summer steelhead. They determined that 55 percent of the recycled steelhead returned to the hatchery and 15 percent of the fish were harvested by anglers. The remaining 30 percent of recycled fish were not known to have been removed from the river. Recycling has not occurred in recent years because definitive studies have not been conducted to determine the fate of the fish that remain in the lower Cowlitz River after being recycled. The U.S. Geological Survey and WDFW conducted a 2-year study during 2012–2014 to quantify recycled steelhead that (1) returned to the hatchery, (2) were captured by anglers, or (3) remained in the river. All recycled steelhead were marked with a Floy ® tag and opercle punch, and 20 percent of the recycled fish were radio-tagged to determine post-release behavior and movement patterns, and to describe locations of tagged fish that remained in the river during the spawning period. During 2012–2013, we recycled 549 steelhead and determined that 50 percent of the fish returned to the hatchery, 18 percent of the fish were harvested by anglers, and 32 percent of the fish were not known to have been removed from the river. During October–December 2012, only 9 percent of the radio-tagged steelhead remained in the lower Cowlitz River and none of these fish entered tributaries monitored by fixed-telemetry sites. The second year of the evaluation was conducted during 2013–2014. A total of 502 steelhead were recycled during June–August and releases were conducted weekly with group sizes that ranged from 30 to 76 fish. Results from 2013–2014 were similar to results from 2012–2013. Fifty percent (251 fish) of the recycled steelhead returned to the hatchery, 20 percent (100 fish) were harvested by anglers, and 30 percent (151 fish) were unaccounted for. The median elapsed time from release to hatchery return was 13 days, and the median elapsed time from release to capture by an angler was 11 days. The percentage of unaccounted-for steelhead in the general population was moderately high (30 percent), but detection records of radio-tagged fish suggest that few recycled steelhead were present in the lower Cowlitz River during the spawning period. A total of 109 steelhead were radio-tagged during 2013–2014, and most of these fish (88 percent) moved upstream following release and entered the Trout Hatchery–Salmon Hatchery reach (river miles 44–51). The median elapsed time from release to reach entry was 4.6 days (range of 0.5–65.5 days). After fish entered this reach, they spent a considerable amount of time near the Cowlitz Trout Hatchery (median residence time of 16.7 hours) or Cowlitz Salmon Hatchery (median residence time of 146.3 hours), or they moved back and forth between these two sites. Thirty radio-tagged steelhead made at least two trips between the sites and some fish made as many as seven trips. Detection records showed that 61 percent (66 fish) of the radio-tagged fish returned to the hatchery reach and 21 percent (23 fish) of the fish were captured by anglers. The remaining 18 percent (20 fish) of the radio-tagged fish had various fates. One fish (less than 1 percent) left the Cowlitz River and nine fish (8 percent) died, were harvested, or spit their transmitter near boat launches in the river. The remaining 10 fish (9 percent) had the potential to interact with winter steelhead. Four tagged steelhead (4 percent) entered lower Cowlitz River tributaries (two fish in the Toutle River; two fish in Salmon Creek) during October and November, and five tagged fish (5 percent) were last detected in the lower Cowlitz River in October. One fish (less than 1 percent) was never detected after being released. We measured the diameter of opercle punches in recycled steelhead to determine the temporal effectiveness of these marks. A total of 116 opercle punches were measured—36 were measured at the time of tagging and 80 were measured when fish returned to the hatchery. Opercle punches remained open for less than 1 month. None of the fish that returned to the hatchery more than 30 days after release had opercle punches that were open. All recycled steelhead were marked with a Floy ® tag and opercle punch. However, if a steelhead lost its Floy ® tag and was captured by an angler, or returned to the hatchery more than 30 days after being recycled, it likely would not have been accurately identified as having been recycled because of regrowth of the opercle punch. During 2013–2014, at least 70 percent of the recycled steelhead were removed from the lower Cowlitz River by anglers, returned to the hatchery, or left the river. Radiotelemetry data indicated that a maximum of 9 percent of the radio-tagged fish remained in the lower Cowlitz River during the spawning period and only 4 percent of the radio-tagged fish entered tributaries where wild steelhead are known to spawn. These results are consistent with findings from previous studies. Overall, results from these studies suggest that about one-third of the recycled steelhead were not known to have been removed from the river. However, the radiotelemetry data indicated that only about 10 percent of the recycled steelhead were present in the lower Cowlitz River during late autumn and early winter, and few of those fish (0 in 2012–2013 and 4 in 2013–2014) entered tributaries where winter steelhead spawn. These results have management implications in the lower Cowlitz River where the risks and rewards of steelhead recycling will be weighed to determine the future of the recycling program.

Washinton↗
USGS2024

Special topic—Eruption plumes and clouds

Introduction Explosive eruptions create plumes of volcanic ash and gas that can rise more than 30,000 feet (9.1 kilometers [km]) above sea level within minutes of eruption onset. The resulting clouds disperse under prevailing winds and may cause hazardous conditions hundreds to thousands of kilometers from the volcano, including in international airspace. Rapid detection and characterization of explosive activity is vital to mitigate the wide-ranging effects of volcanic ash. Ashfall thicknesses as small as a millimeter or so on the ground can affect infrastructure, agriculture, and air quality, requiring extensive clean-up procedures (Schuster, 1981; Warrick and others, 1981, U.S. Geological Survey, 2022). Volcanic clouds also pose substantial threats to aircraft. Since 1953, 88 encounters between airplanes and ash clouds have been documented worldwide (International Civil Aviation Organization, 2015, appendix F), resulting in aircraft damage and, in 9 cases, engine failure (Guffanti and others, 2010). In 1982, two large passenger planes suffered complete engine failure owing to eruptions in Indonesia (Global Volcanism Program, 1982) and a similar incident occurred over Alaska in 1989 (Casadevall, 1994). In all three cases, they were able to restart some engine capability and land safely once they emerged from the ash clouds, although with substantial damage (Guffanti and others, 2010). The clear threat to aviation has led to establishment of nine Volcanic Ash Advisory Centers (VAAC) around the world to monitor and rapidly disseminate information about volcanic eruptions to the aviation community. U.S. Geological Survey (USGS) volcano observatories issue the Volcano Observatory Notice for Aviation that informs of preeruptive unrest or eruptive activity. When ash-producing eruptions do occur, volcano observatories work closely with their regional VAAC to ensure consistency and accuracy in eruption onset time, cloud altitude, ash production, and duration as reported in Volcanic Ash Advisories. Explosive volcanism in the United States and Commonwealth of the Northern Mariana Islands prompts 50–100 such advisories in any given year (table J1). This collaborative effort is greatly aided by USGS detection and monitoring of eruption clouds to ensure a timely and coordinated response. To support these efforts to provide guidance on ash transport and fallout, the USGS developed the Ash3d volcanic ash dispersion model ( https://vsc-ash.wr.usgs.gov/ash3d-gui ) (Schwaiger and others, 2012). Automated simulations are run daily by the USGS for volcanoes that are in elevated states of unrest, and in response mode when eruptions occur. During eruptions, the model output is provided to local National Weather Service Weather Forecast Offices to guide them in the issuance of their information products (such as special weather statements, ashfall advisories, or ashfall warnings), as well as to State and local governments and the public. Characterization of the eruption source is needed to estimate the parameters used to initialize the Ash3d model, and by the Anchorage and Washington VAACs to initialize other dispersion models that inform forecasts for the airborne volcanic cloud. The source parameters that can be provided by observation during an eruption include eruption start time, eruption cloud height over time, and eruption duration. Other, nonobservable source parameters, such as mass eruption rate and grain-size distribution, are based on empirical correlations and study of historical deposits. The goal is to provide a time series of cloud heights, mass eruption rates, and particle-size distributions that accurately reflects current conditions. When feasible, the USGS also provides guidance on the nature of ongoing eruptions and forecasts future activity using petrologic monitoring of collected tephra samples. The aims of providing accurate observable parameters are achieved through analysis of (1) near-real-time meteorological satellite data, (2) ground-based cameras (see of Flinders, A.F., Lowenstern, J.B., Coombs, M.L., and Poland, M.P., eds., Recommended capabilities and instrumentation for volcano monitoring in the United States: U.S. Geological Survey Scientific Investigations Report 2024–5062–G, 11 p., https://doi.org/10.3133/sir20245062g.">chapter G , this volume; Orr and others, 2024), (3) weather radar, (4) volcanic lightning detection, and (5) ground-based ash sensors and sampling. Explosive eruptions can be detected by a variety of geophysical monitoring, including infrasound (see of Flinders, A.F., Lowenstern, J.B., Coombs, M.L., and Poland, M.P., eds., Recommended capabilities and instrumentation for volcano monitoring in the United States: U.S. Geological Survey Scientific Investigations Report 2024–5062–C, 11 p., https://doi.org/10.3133/sir20245062c.">chapter C , this volume; Lyons and others, 2024) and seismicity (see of Flinders, A.F., Lowenstern, J.B., Coombs, M.L., and Poland, M.P., eds., Recommended capabilities and instrumentation for volcano monitoring in the United States: U.S. Geological Survey Scientific Investigations Report 2024–5062–B, 9 p., https://doi.org/10.3133/sir20245062b.">chapter B , this volume; Thelen and others, 2024). However, those methods cannot quantify the altitude, ash content, and dispersal dynamics of resulting volcanic clouds. Ideally, all available sources of monitoring data are synthesized to develop a coherent understanding of eruptive activity. The guidance summarized here provides a framework for characterizing volcanic clouds in the atmosphere and tracking the evolution of explosive eruption dynamics.

Scientific Investigations Report↗
USGS1985

Suitability of nonwelded pyroclastic-flow deposits for studies of magnetic secular variation: A test based on deposits emplaced at Mount St. Helens, Washington, in 1980

Paleomagnetic directions obtained from nonwelded pyroclastic-flow deposits that were emplaced at Mount St. Helens, Washington, in 1980 have a precision and accuracy similar to data obtainable from lava flows. It is concluded that nonwelded pyroclastic-flow deposits, like lava flows, are suitable for studies of magnetic secular variation. Although clast rotations apparently caused an “inclination error” in the paleomagnetic directions, the error is a few degrees at most.

Washington↗
USGS1974

Yachats Basalt: An upper Eocene differentiated volcanic sequence in the Oregon Coast Range

The name Yadials Basalt is proposed for a sequence of largely subacrial basalt flows and breccias and associated dikes of late Eocene age that arc exposed along the central Oregon coast. These volcanic rocks, which have a maximum thickness of 750 m, are underlain by marine siltstonc of late Eocene age and overlain by marine siltstone and basaltic sandstone, also of late Eocene age. The siltstone contains a foraminiferal fauna indicative of a moderately deepwatcr marine environment, indicating that local uplift preceded the extrusion of the flows and local subsidence followed. The Yachats Basalt varies widely in composition. Although the bulk of the extrusive rocks and dikes arc basalt, some grade in composition to basaltic andcsite and andcsite; a few dikes are rhyodacitic. Most of the rocks arc porphyritic with phcnocrysts of labradorite and less commonly augite and olivine. Typical flow rock contains 50 percent SiO 2 and are characterized by high alumina, alkali, titania, and phosphate content. The wide range in composition and porphyritic character of the Yachats Basalt and the abundance of multiple dikes suggest that the magma that produced these rocks was differentiated in the upper crust before extrusion. The Yachats Basalt, and correlative upper Eocene volcanic rocks in western Oregon and Washington, lie along a generally north-trending belt. The predominance of normal faulting in western Oregon and Washington and on the adjacent continental shelf during post mid-late Eocene time suggests that the volcanics were extruded along a zone of tensional rifting. They do not appear to be related to conventional plate models for continental margins that arc characterized by deep trenches flanked by island arcs.

Oregon↗
USGS2009

Groundwater/surface-water interactions in the Tunk, Bonaparte, Antoine, and Tonasket Creek Subbasins, Okanogan River Basin, North-Central Washington, 2008

An investigation into groundwater/surface-water interactions in four tributary subbasins of the Okanogan River determined that streamflows and shallow groundwater levels beneath the streams varied seasonally and by location. Streamflows measured in June 2008 indicated net losses of streamflow along 10 of 17 reaches, and hydraulic gradients measured between streams and shallow groundwater indicated potential recharge of surface water to groundwater at 11 of 21 measurement sites. In September 2008, net losses of streamflow were indicated along 9 of 17 reaches, and potential recharge of surface water to groundwater was indicated at 18 of 21 measurement sites. The greatest losses of streamflow occurred near the confluences with the Okanogan River, likely due to the presence of thick layers of unconsolidated deposits in the flood plain of the Okanogan River. Based on available geologic information compiled from drillers' logs, a surficial geologic map, and streamflow records, the extensive and thick deposits of unconsolidated material in the Tunk and Bonaparte Creek subbasins are factors in sustaining the almost perennial streamflow in those creeks. The less extensive and generally thinner unconsolidated deposits in the Tonasket and Antoine subbasins are contributing factors to the occasional extended periods of zero flow (a dry stream channel) in those creeks. Even though groundwater withdrawals would affect streamflows, relatively low precipitation in the area, along with limited groundwater storage capacity and the presence of permeable, unconsolidated deposits underlying the stream channels, would likely lead to loss of surface water to the groundwater system without any withdrawals.

Scientific Investigations Report↗
USGS1995

Radiocarbon evidence for extensive plate-boundary rupture about 300 years ago at the Cascadia subduction zone

The Cascadia subduction zone, a region of converging tectonic plates along the Pacific coast of North America, has a geological history of very large plate-boundary earthquakes1,2, but no such earthquakes have struck this region since Euro-American settlement about 150 years ago. Geophysical estimates of the moment magnitudes (Mw) of the largest such earthquakes range from 8 (ref. 3).to 91/2 (ref. 4). Radiocarbon dating of earthquake-killed vegetation can set upper bounds on earthquake size by constraining the length of plate boundary that ruptured in individual earthquakes. Such dating has shown that the most recent rupture, or series of ruptures, extended at least 55 km along the Washington coast within a period of a few decades about 300 years ago5. Here we report 85 new 14C ages, which suggest that this most recent rupture (or series) extended at least 900 km between southern British Columbia and northern California. By comparing the 14C ages with written records of the past 150 years, we conclude that a single magnitude 9 earthquake, or a series of lesser earthquakes, ruptured most of the length of the Cascadia subduction zone between the late 1600s and early 1800s, and probably in the early 1700s.

California, Oregon, Washington↗
USGS2010

Wind River water restoration, Annual report November 2008 to October 2009.

This report summarizes work completed by U.S. Geological Survey’s Columbia River Research Laboratory (USGS-CRRL) in the Wind River subbasin during the period November 2008 through October 2009 under Bonneville Power Administration (BPA) contract 41038. Long term research in the Wind River has focused on assessments of steelhead/rainbow trout Oncorhynchus mykiss populations, interactions with introduced populations of spring Chinook salmon O. tshawytscha and brook trout Salvelinus fontinalis, and influences of habitat variables on fish productivity. During this period, we collected water temperature data to characterize variation within and among tributaries and mainstem sections in the Trout Creek watershed, and assisted Washington Department of Fish and Wildlife with smolt trapping and tagging of smolt and parr steelhead with passive integrated transponder (PIT) tags. We also continued to maintain and test efficacy of a passive integrated transponder tag interrogation system (PTIS) in Trout Creek for assessing the adult steelhead runsize. We continued to maintain and download PTIS setups in the fish ladder at Hemlock Dam. These PTISs contributed information on movement and rearing of steelhead parr and smolts. A statement of work (SOW) was submitted to BPA in October 2009 that outlined work to be performed by USGS-CRRL. The SOW was organized by work elements, with each describing a research task. This report summarizes the progress completed under each work element.

Report↗
USGS2013

Use of surrogate technologies to estimate suspended sediment in the Clearwater River, Idaho, and Snake River, Washington, 2008-10

Elevated levels of fluvial sediment can reduce the biological productivity of aquatic systems, impair freshwater quality, decrease reservoir storage capacity, and decrease the capacity of hydraulic structures. The need to measure fluvial sediment has led to the development of sediment surrogate technologies, particularly in locations where streamflow alone is not a good estimator of sediment load because of regulated flow, load hysteresis, episodic sediment sources, and non-equilibrium sediment transport. An effective surrogate technology is low maintenance and sturdy over a range of hydrologic conditions, and measured variables can be modeled to estimate suspended-sediment concentration (SSC), load, and duration of elevated levels on a real-time basis. Among the most promising techniques is the measurement of acoustic backscatter strength using acoustic Doppler velocity meters (ADVMs) deployed in rivers. The U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, Walla Walla District, evaluated the use of acoustic backscatter, turbidity, laser diffraction, and streamflow as surrogates for estimating real-time SSC and loads in the Clearwater and Snake Rivers, which adjoin in Lewiston, Idaho, and flow into Lower Granite Reservoir. The study was conducted from May 2008 to September 2010 and is part of the U.S. Army Corps of Engineers Lower Snake River Programmatic Sediment Management Plan to identify and manage sediment sources in basins draining into lower Snake River reservoirs. Commercially available acoustic instruments have shown great promise in sediment surrogate studies because they require little maintenance and measure profiles of the surrogate parameter across a sampling volume rather than at a single point. The strength of acoustic backscatter theoretically increases as more particles are suspended in the water to reflect the acoustic pulse emitted by the ADVM. ADVMs of different frequencies (0.5, 1.5, and 3 Megahertz) were tested to target various sediment grain sizes. Laser diffraction and turbidity also were tested as surrogate technologies. Models between SSC and surrogate variables were developed using ordinary least-squares regression. Acoustic backscatter using the high frequency ADVM at each site was the best predictor of sediment, explaining 93 and 92 percent of the variability in SSC and matching sediment sample data within +8.6 and +10 percent, on average, at the Clearwater River and Snake River study sites, respectively. Additional surrogate models were developed to estimate sand and fines fractions of suspended sediment based on acoustic backscatter. Acoustic backscatter generally appears to be a better estimator of suspended sediment concentration and load over short (storm event and monthly) and long (annual) time scales than transport curves derived solely from the regression of conventional sediment measurements and streamflow. Changing grain sizes, the presence of organic matter, and aggregation of sediments in the river likely introduce some variability in the model between acoustic backscatter and SSC.

Idaho;Washington↗
USGS2017

Control of landslide volume and hazard by glacial stratigraphic architecture, Northwest Washington state, USA

Landslide volumes span many orders of magnitude, but large-volume slides tend to travel farther and consequently can pose a greater hazard. In northwest Washington State, USA, a landscape abounding with landslides big and small, the recent occurrence of the large-volume and tragically deadly State Route 530 (Oso) landslide is a stark reminder of the hazards associated with glacial terraces lining valleys of the western Cascade Range. What controls the differences in location and size of these slope failures? Here, we examine the control on landslide volume and failure style by terrace sedimentary architecture. We analyze lidar topographic data in three nearby valleys and find significant variation in landslide deposit volumes, morphology, and relative mobility in each valley. Geologic data show that each site differs in the thickness and position of outwash, tills, and glaciolacustrine clays. Combining a three-dimensional limit-equilibrium slope-stability analysis (Scoops3D) with simulations of variably saturated groundwater flow (VS2Dt), we show that landslide volumes are highly sensitive both to the distribution of material strength as well as the location of perched water tables. Modeled landslides match observed failure sizes and depths in all valleys when the effects of variably saturated groundwater flow are included. The position and thickness of low-strength strata act as first-order controls on landslide volume, with peak volumes for stratigraphic geometries similar to that of the valley containing the Oso landslide. Knowledge of feedbacks between lithology and hydrology is therefore critical to assess the landslide hazard and evolution of landscapes composed of stratigraphically layered units.

Washington↗
USGS2000

Is seawater intrusion affecting ground water on Lopez Island, Washington?

Lopez Island lies among the San Juan Islands, an archipelago in the coastal waters of Washington State, just offshore of Seattle and of Vancouver, British Columbia. Its scenic views and relatively little precipitation have made it one of Washington's premier places to live and play. So its population has been burgeoning, and its interior and shorelines have been under development. The Island's main freshwater source is ground water. Local surface water cannot be developed to meet increasing needs for freshwater because the Island lacks lakes and continuously flowing streams. But Islanders are concerned that pumping more ground water will affect its availability and quality. Because many wells are near the shores and the recharge rates to the aquifers are low, there is a great potential for seawater intrusion. In 1997, the U.S. Geological Survey (USGS), in cooperation with the San Juan County Conservation District, studied the possibilities of seawater intrusion on the Island and found that 46 percent of 185 freshwater samples had chloride concentrations indicating seawater intrusion.

Washington↗
USGS2008

The critical role of volcano monitoring in risk reduction

Data from volcano-monitoring studies constitute the only scientifically valid basis for short-term forecasts of a future eruption, or of possible changes during an ongoing eruption. Thus, in any effective hazards-mitigation program, a basic strategy in reducing volcano risk is the initiation or augmentation of volcano monitoring at historically active volcanoes and also at geologically young, but presently dormant, volcanoes with potential for reactivation. Beginning with the 1980s, substantial progress in volcano-monitoring techniques and networks - ground-based as well space-based - has been achieved. Although some geochemical monitoring techniques (e.g., remote measurement of volcanic gas emissions) are being increasingly applied and show considerable promise, seismic and geodetic methods to date remain the techniques of choice and are the most widely used. Availability of comprehensive volcano-monitoring data was a decisive factor in the successful scientific and governmental responses to the reawakening of Mount St. Helens (Washington, USA) in 1980 and, more recently, to the powerful explosive eruptions at Mount Pinatubo (Luzon, Philippines) in 1991. However, even with the ever-improving state-ofthe-art in volcano monitoring and predictive capability, the Mount St. Helens and Pinatubo case histories unfortunately still represent the exceptions, rather than the rule, in successfully forecasting the most likely outcome of volcano unrest.

Advances in Geosciences↗
USGS2007

Hydrogeologic characterization of the Brazos River Alluvium Aquifer, Bosque County to Fort Bend County, Texas

Introduction The Brazos River alluvium aquifer underlies the Brazos River in Texas from Bosque County to Fort Bend County. The aquifer, one of 21 minor aquifers in the State, supplies water for irrigation, domestic, stock, and commercial use. The Brazos River alluvium aquifer likely will become more important in the future as demand for water increases statewide. A thorough understanding of the hydrogeology of the alluvium aquifer will be the foundation for future studies in the area. During October 2006-April 2007, the U.S. Geological Survey, in cooperation with the Texas Water Development Board, conducted a study to delineate the altitude of the top, altitude of the base, and thickness of the Brazos River alluvium aquifer, and to compile and summarize available hydraulic property (specific capacity, transmissivity, and hydraulic conductivity) data. A digital elevation model was used as the altitude of the top of the aquifer. The altitude of the base of the aquifer was generated using data from wells. The study area encompasses the Brazos River alluvium aquifer in parts of Bosque, Hill, McLennan, Falls, Robertson, Milam, Brazos, Burleson, Grimes, Washington, Waller, Austin, and Fort Bend Counties and a 1.5-mile-wide lateral buffer adjacent to the aquifer. The results of this study will be used by the Texas Water Development Board for input into a ground-water availability model.

Scientific Investigations Map↗
USGS2007

Map and data for Quaternary faults and fault systems on the Island of Hawai'i

Introduction This report and digitally prepared, GIS-based map is one of a series of similar products covering individual states or regions of United States that show the locations, ages, and activity rates of major earthquake-related features such as faults and fault-related folds. It is part of a continuing the effort to compile a comprehensive Quaternary fault and fold map and database for the United States, which is supported by the U.S. Geological Survey's (USGS) Earthquake Hazards Program. Guidelines for the compilation of the Quaternary fault and fold maps for the United States were published by Haller and others (1993) at the onset of this project. This compilation of Quaternary surface faulting and folding in Hawai`i is one of several similar state and regional compilations that were planned for the United States. Reports published to date include West Texas (Collins and others, 1996), New Mexico (Machette and others, 1998), Arizona (Pearthree, 1998), Colorado (Widmann and others, 1998), Montana (Stickney and others, 2000), Idaho (Haller and others, 2005), and Washington (Lidke and others, 2003). Reports for other states such as California and Alaska are still in preparation. The primary intention of this compilation is to aid in seismic-hazard evaluations. The report contains detailed information on the location and style of faulting, the time of most recent movement, and assigns each feature to a slip-rate category (as a proxy for fault activity). It also contains the name and affiliation of the compiler, date of compilation, geographic and other paleoseismologic parameters, as well as an extensive set of references for each feature. The map (plate 1) shows faults, volcanic rift zones, and lineaments that show evidence of Quaternary surface movement related to faulting, including data on the time of most recent movement, sense of movement, slip rate, and continuity of surface expression. This compilation is presented as a digitally prepared map product and catalog of data, both in Adobe Acrobat PDF format. The senior authors (Eric C. Cannon and Roland Burgmann) compiled the fault data as part of ongoing studies of active faulting on the Island of Hawai`i. The USGS is responsible for organizing and integrating the State or regional products under their National Seismic Hazard Mapping project, including the coordination and oversight of contributions from individuals and groups (Michael N. Machette and Anthony J. Crone), database design and management (Kathleen M. Haller), and digitization and analysis of map data (Richard L. Dart). After being released an Open-File Report, the data in this report will be available online at http://earthquake.usgs.gov/regional/qfaults/, the USGS Quaternary Fault and Fold Database of the United States.

Hawaii↗
USGS1994

Hydrogeology, simulation of regional ground-water flow, and saltwater intrusion, Potomac-Raritan-Magothy Aquifer System, Northern Coastal Plain of New Jersey

The Potomac-Raritan-Magothy aquifer system in Middlesex and Monmouth Counties in the northern Coastal Plain of New Jersey consists primarily of unconsolidated Cretaceous sediments, which are divided into the upper and middle aquifers and confining units. These units, which strike northeastsouthwest along the Fall Line, dip and thicken to the southeast. The upper aquifer consists primarily of the Old Bridge Sand Member of the Magothy Formation, which is composed of coarse-grained sands, localized thin clay beds, and younger surficial sands and gravels in and near the outcrop. Transmissivity ranges from 1,760 to 19,400 ft 2 /d (feet squared per day) and tends to be higher in updip areas. Estimated withdrawals from the upper aquifer in the northern Coastal Plain were approximately 42 Mgal/d (million gallons per day) in 1986. Cones of depression whose centers range from 36 to 42 ft (feet) below sea level have developed as a result of these withdrawals. The upper aquifer is confined throughout most of the northern New Jersey Coastal Plain by clays and silts of the Cretaceous Woodbury Clay and Merchantville Formation and younger sediments of the Magothy Formation. This confining unit generally is greater than 200 ft thick. The simulated vertical hydraulic conductivity for the confining unit ranges from 8.4 x 10 -5 to 5.6 x 10 -3 feet per day; interpreted vertical hydraulic conductivities generally are lower except in southwestern Middlesex County, where the vertical hydraulic conductivities of the confining unit are higher. The middle aquifer consists primarily of the Farrington Sand Member of the Cretaceous Raritan Formation and surficial Holocene and Miocene sands and gravels in its outcrop area. It also can include the uppermost sands of the Cretaceous Potomac Group in parts of Monmouth County. The middle aquifer is composed of fine to coarse sand that contains some lignite and pyrite, and, locally, some clay beds. It pinches out in the northern part of Sayreville Township, near Raritan River. The transmissivity of the aquifer ranges from 2,140 to 13,800 ft 2/ d and tends to decrease in the northern part of the northern Coastal Plain of New Jersey where the aquifer thins. A poorly permeable confining unit composed mostly of clays and silts of the Woodbridge Clay Member of the Raritan Formation overlies the aquifer in most of this area. The confining unit generally is greater than 100 ft thick, although it thins and is sandy in the southwestern part of Middlesex County, where a good hydraulic connection exists between the middle and upper aquifers. Estimated withdrawals from the middle aquifer in the northern Coastal Plain were about 22 Mgal/d in 1986. These withdrawals have caused cones of depression whose centers range from 77 to 93 ft below sea level. A finite-difference, quasi-three-dimensional ground-water flow model was developed to simulate ground-water flow in the aquifer system. The confined and unconfined areas of the upper and middle aquifers were modeled as separate layers. The model was calibrated primarily by adjusting vertical hydraulic conductivity in the confining units and horizontal hydraulic conductivity in the aquifers, then matching simulated and measured groundwater levels for the period 1896-1986 and simulated and interpreted potentiometric surfaces under predevelopment conditions and in 1984. For the predevelopment period, the total flow into and out of the upper and middle aquifers is 35 and 21 Mgal/d, respectively. Recharge to the aquifer system is from direct recharge in the unconfined areas and from vertical leakage through overlying confining units. The main recharge areas are the topographically high areas in southwestern Middlesex County for both aquifers, in the eastern Sayreville area for the upper aquifer, and north of the Raritan River for the middle aquifer. Most ground water discharges to low-lying regional surface-water drains (streams), which flow into the South River. For 1984 transient conditions, the total ground-water flow into and out of the upper and middle aquifers is 61 and 34 Mgal/d, respectively. The largest amount of recharge is from direct recharge in the unconfined areas, but some recharge also is derived from vertical leakage through the Merchantville-Woodbury confining unit, captured ground-water discharge to streams, and induced inflow at artificial-recharge facilities. Regional flow is from recharge areas toward major cones of depression. Sensitivity analysis showed that the model was useful for representing flow in the system, especially in the confined-aquifer areas. Model representation of lateral and vertical boundary conditions was judged acceptable. Simulation results were less sensitive to changes in aquifer properties in the unconfined areas of the aquifers and to changes in storage in the confining units. Sensitivity analysis and calibration of hydraulic parameters and conditions showed that the distribution of hydraulic head was sensitive to changes in horizontal hydraulic conductivity in the aquifers, vertical hydraulic conductivity in the confining units, magnitudes of ground-water withdrawals, and initial hydraulic head in aquifer outcrop areas. Two scenarios were simulated to determine the effects of ground-water withdrawals from 1986 through 2019. For the scenario in which ground-water withdrawals increase to about 69 Mgal/d in the upper aquifer and 37 Mgal/d in the middle aquifer, centers of cones of depression are as deep as 100 ft below sea level in the upper aquifer and 170 ft below sea level in the middle aquifer. For this scenario, most of the additional water comes from captured surface-water discharge, induced cross-formational flow from overlying aquifers, and increases in induced flow from artificial-recharge areas. Induced flow from Raritan Bay also increases. For the scenario in which ground water withdrawals are reduced to 42.5 Mgal/d in the upper aquifer and 15 Mgal/d in the middle aquifer, water levels recover to above sea level nearly everywhere. In each aquifer, ground-water discharge to streams increases and induced flow through the confining units and from the overlying sediments decreases, and discharge of ground water to Raritan Bay in the upper aquifer exceeds the induced recharge from Raritan Bay. Reversal of ground-water gradients has caused saltwater intrusion in the two aquifers. Chloride concentrations in water from the upper aquifer in Keyport and Union Beach Boroughs were as high as 2,100 mg/L (milligrams per liter) in 1986. The intrusion has not increased significantly since well fields in the area were closed in the late 1970's. Elevated chloride concentrations also were measured in Keanesburg Borough in 1986. In both of these areas, saltwater has entered the upper aquifer from the Bay because of movement of the freshwater-saltwater interface in response to increasing ground-water withdrawals. Chloride concentrations in well-water samples from the middle aquifer were as high as 6,000 mg/L in Sayreville Borough in 1987; concentrations in samples from drive-point wells from the same aquifer near the Washington Canal, the main source of saltwater, were as high as 7,100 mg/L. The migration of the saltwater front at about 470 feet per year to the southeast is influenced mainly by a thinning of the middle aquifer, which constrains flow, and by the locations of regional cones of depression caused by groundwater withdrawals.

New Jersey↗
USGS2024

Special topic—Rapid-response instrumentation

Introduction Based on the reports of Ewert and others (2005, 2018) and Moran and others (2008), most U.S. volcanoes are currently under-monitored and are likely to remain so until the goals of the National Volcano Early Warning System are fulfilled. In addition, volcanoes determined to have low to moderate threat levels (Ewert and others 2005, 2018) could awaken suddenly and, as a result, may need to have instrumentation installed rapidly. For these reasons, equipment caches would ideally be readily available for rapid response in the event of unrest at under-monitored volcanoes or during a volcanic crisis. Given that volcanoes in Alaska and Hawai‘i are frequently active, it is likely that several U.S. volcanoes could experience unrest simultaneously, as happened in 2018, 2019, and 2020, when unrest or eruptions occurred at Great Sitkin Volcano, Alaska; Mauna Loa, Hawai‘i; Mount Cleveland, Alaska; Semisopochnoi Island, Alaska; Shishaldin Volcano, Alaska; Mount Veniaminof, Alaska, as well as the most destructive documented eruption of Kīlauea, Hawai‘i. Therefore, we recommend that sufficient numbers of seismometers, infrasound sensors, Global Navigation Satellite System (GNSS) receivers, remote cameras, gas-monitoring instruments, and airborne and ground-based remote-sensing systems be made available and placed in a state of readiness at each observatory with the capability of bringing a level-2 monitoring network to near level-4 readiness. These rapid-response caches would ideally include sufficient equipment to provide real-time data telemetry, including satellite telemetry, where available, applicable, and appropriate. Rapid-response caches would be maintained in a state of readiness so that instruments can be deployed within several hours to days. Although the primary focus of the caches would be to enable rapid increases to a volcano observatory’s real-time monitoring capabilities, not all scenarios of volcanic unrest are conducive to rapid deployment of real-time data telemetry. Non-telemetered, campaign instruments, particularly seismometers and GNSS stations, can also be deployed to aid in detection of early signs of volcanic unrest given the data can be recovered in a timely fashion. Given the geographic separation of the U.S. Geological Survey Volcano Science Center’s (VSC) four volcano observatory offices, the logistical difficulties in shipping equipment rapidly between them in response to unrest, the possible scenario that a volcano could reawaken with just hours or days of precursory unrest, and the difference in operating environments (for example, tropical Hawai‘i compared to subarctic Alaska), we recommend three rapid-response instrument caches—for Hawai‘i, Alaska, and the lower 48 States. For the lower 48 States, a single cache shared among the Cascades Volcano Observatory, Yellowstone Volcano Observatory, and the California Volcano Observatory could be warehoused in California or Washington. Although these rapid-response caches would be located at one of the observatories, they would ideally be owned and maintained by VSC, and together form a flexible VSC-wide instrument pool. To maintain continuity of monitoring capabilities, this rapid-response cache could also serve to replace instruments destroyed during an on-going eruption. However, to retain eruption-response readiness, we recommend instruments in the rapid-response cache not be permanently reallocated to an observatory’s monitoring network unless they are replaced.

Scientific Investigations Report↗
USGS1996

Surface-water hydrology and runoff simulations for three basins in Pierce County, Washington

The surface-water hydrology in Clear, Clarks, and Clover Creek Basins in central Pierce County, Washington, is described with a conceptual model of the runoff processes and then simulated with the Hydrological Simulation Program-FORTRAN (HSPF), a continuous, deterministic hydrologic model. The study area is currently undergoing a rapid conversion of rural, undeveloped land to urban and suburban land that often changes the flow characteristics of the streams that drain these lands. The complex interactions of land cover, climate, soils, topography, channel characteristics, and ground- water flow patterns determine the surface-water hydrology of the study area and require a complex numerical model to assess the impact of urbanization on streamflows. The U.S. Geological Survey completed this investigation in cooperation with the Storm Drainage and Surface Water Management Utility within the Pierce County Department of Public Works to describe the important rainfall-runoff processes within the study area and to develop a simulation model to be used as a tool to predict changes in runoff characteristics resulting from changes in land use. The conceptual model, a qualitative representation of the study basins, links the physical characteristics to the runoff process of the study basins. The model incorporates 11 generalizations identified by the investigation, eight of which describe runoff from hillslopes, and three that account for the effects of channel characteristics and ground-water flow patterns on runoff. Stream discharge was measured at 28 sites and precipitation was measured at six sites for 3 years in two overlapping phases during the period of October 1989 through September 1992 to calibrate and validate the simulation model. Comparison of rainfall data from October 1989 through September 1992 shows the data-collection period beginning with 2 wet water years followed by the relatively dry 1992 water year. Runoff was simulated with two basin models-the Clover Creek Basin model and the Clear-Clarks Basin model-by incorporating the generalizations of the conceptual model into the construction of two HSPF numerical models. Initially, the process-related parameters for runoff from glacial-till hillslopes were calibrated with numerical models for three catchment sites and one headwater basin where streamflows were continuously measured and little or no influence from ground water, channel storage, or channel losses affected runoff. At one of the catchments soil moisture was monitored and compared with simulated soil moisture. The values for these parameters were used in the basin models. Basin models were calibrated to the first year of observed streamflow data by adjusting other parameters in the numerical model that simulated channel losses, simulated channel storage in a few of the reaches in the headwaters and in the floodplain of the main stem of Clover Creek, and simulated volume and outflow of the ground-water reservoir representing the regional ground-water aquifers. The models were run for a second year without any adjustments, and simulated results were compared with observed results as a measure of validation of the models. The investigation showed the importance of defining the ground-water flow boundaries and demonstrated a simple method of simulating the influence of the regional ground-water aquifer on streamflows. In the Clover Creek Basin model, ground-water flow boundaries were used to define subbasins containing mostly glacial outwash soils and not containing any surface drainage channels. In the Clear-Clarks Basin model, ground-water flow boundaries outlined a recharge area outside the surface-water boundaries of the basin that was incorporated into the model in order to provide sufficient water to balance simulated ground-water outflows to the creeks. A simulated ground-water reservoir used to represent regional ground-water flow processes successfully provided the proper water balance of inflows and outfl

Washington↗
USGS1983

Mudflow hazards along the Toutle and Cowlitz Rivers from a hypothetical failure of Spirit Lake blockage

The debris avalanche accompanying the May 18, 1980, eruption of Mount St. Helens, in southwestern Washington, buried the former outlet of Spirit Lake, located 5 miles north of the volcano, to a depth ranging to 500 feet. Since that time, Spirit Lake has had no natural outlet and its lake level and contents have increased significantly. Erosion at the crest of the debris dam on the surface of the blockage and recent studies of theblockage stratigraphy and soil properties showing that the effective crest elevation is lower than the surface crest have led to concern that the lake may someday breach through or spill over the top of the blockage. A study was made by the U.S. Geological Survey to determine the extent of inundation that might result downstream in the Toutle and Cowlitz Rivers if a hypothetical breach should occur and generate a mudflow flood of catastrophic proportions. A hypothetical breach of Spirit Lake produced a hypothetical mudflow hydrograph with a peak discharge of 2.65 million cu ft/s and a sediment concentration of 65 percent by volume at Camp Baker on the North Fork Toutle River. Elevations determined by the hydraulic routing of the mudflow were used to prepare inundation maps, indicating depths of inundation to be about 60 feet at Castle Rock and Lexington; 30-40 feet at Toutle, Toutle Lake at Silver Lake, Kelson, and Longview; and 15-20 feet at Toledo. Travel times for the peak elevation were estimated to be about 15 hours to Kid Valley on the North Fork Toutle River, 21 hours to Castle Rock, 22 hours to Toledo, and 23 hours to Kelso and Longview on the Cowlitz River. (USGS)

Water-Resources Investigations Report↗