SEARCH · Geology Reports

Results for “Journal of Basin Research”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources

USGS2018

Biomonitoring using invasive species in a large Lake: Dreissena distribution maps hypoxic zones

Due to cultural eutrophication and global climate change, an exponential increase in the number and extent of hypoxic zones in marine and freshwater ecosystems has been observed in the last few decades. Hypoxia, or low dissolved oxygen (DO) concentrations, can produce strong negative ecological impacts and, therefore, is a management concern. We measured biomass and densities of Dreissena in Lake Erie, as well as bottom DO in 2014 using 19 high frequency data loggers distributed throughout the central basin to validate a three-dimensional hydrodynamic-ecological lake model. We found that a deep, offshore hypoxic zone was formed by early August, restricting the Dreissena population to shallow areas of the central basin. Deeper than 20 m, where bottom hypoxia routinely develops, only young of the year mussels were found in small numbers, indicating restricted recruitment and survival of young Dreissena . We suggest that monitoring Dreissena distribution can be an effective tool for mapping the extent and frequency of hypoxia in freshwater. In addition, our results suggest that an anticipated decrease in the spatial extent of hypoxia resulting from nutrient management has the potential to increase the spatial extent of profundal habitat in the central basin available for Dreissena expansion.

Lake Erie↗

USGS2005

Occurrence of Cyathocephalus truncatus (Cestoda) in fishes of the Great Lakes with emphasis on its occurrence in round gobies (Neogobius melanostomus) from Lake Huron

Cyathocephalus truncatus is a pathogenic cestode that is common in many Laurentian Great Lakes fish species, but the depth distribution of this cestode has not been studied. Cyathocephalus truncatus has been reported from 21 fish species and one hybrid representing seven orders and nine families in Lakes Superior, Michigan, Huron, and Ontario. We examined the intestinal contents of six species of fish collected in Michigan waters of Lake Huron, from DeTour to Harbor Beach, in 2001 to 2003 for the presence of this cestode species. Cyathocephalus truncatus was found in five native fish species and the exotic round goby. Prevalence (52%) and mean intensity (4.6 cestodes per infected fish) were highest in bloaters. This is the first reported occurrence of this cestode in round gobies from the Great Lakes. None of the gobies trawled from Lake Huron at depths of 27 to 46 m were infected, but prevalence and intensity of infection in round gobies increased significantly with depth from 55 to 73 m. Our diet study of round gobies indicated that they preyed heavily on amphipods ( Diporeia hoyi ) at depths of 55 to 73 m. Cyathocephalus truncatus was found in eight of 605 D. hoyi obtained by Ponar grab sampling. This suggests that C. truncatus eggs may be released from infected gobies and sink to deep basins with silt bottoms where D. hoyi occur.

Lake Huron↗

USGS2020

Magma intrusion and volatile ascent beneath Norris Geyser Basin, Yellowstone National Park

Recent activity has provided new insights into the causes of surface deformation in and around the Yellowstone Caldera, a topic that has been debated since the discovery of caldera floor uplift more than four decades ago. An episode of unusually rapid uplift (>15 cm/yr) centered near Norris Geyser Basin along the north caldera rim began in late 2013 and continued until a M w 4.9 earthquake on 30 March 2014; thereafter, uplift abruptly switched to subsidence. Uplift at rates of several centimeters per year resumed in 2016 and continued at least through the end of 2018. Modeling of Global Positioning System and interferometric synthetic aperture radar data suggests an evolving process of deep magma intrusion during 1996–2001 followed by volatile ascent and accumulation at shallow levels, perhaps as shallow as a few hundred meters depth. The depth of shallow volatile accumulation appears to have shallowed from the 2014 to the 2016 deformation episode, and frequent eruptions of Steamboat Geyser since March 2018 are likely a surface manifestation of this ongoing process. Hydrothermal explosion features are prominent in the Norris Geyser Basin area, and the apparent shallow nature of the volatile accumulation implies an increased risk of hydrothermal explosions.

Wyoming↗

USGS2012

Distribution of late Cenozoic volcanic vents in the Cascade Range: Volcanic arc segmentation and regional tectonic considerations

Spatial, temporal, and compositional distributions of approximately 4000 volcanic vents formed since 16 Ma in Washington, Oregon, northern California, and northwestern Nevada illustrate the evolution of volcanism related to subduction of the Juan de Fuca plate system and extension of the Basin and Range province. Vent data were obtained from published map compilations and include monogenetic and small polygenetic volcanoes in addition to major composite centers. On the basis of the distribution of 2821 vents formed since 5 Ma, the Cascade Range is divided into five segments, with vents of the High Lava Plains along the northern margin of the Basin and Range province in Oregon forming a sixth segment. Some aspects of the Cascade Range segmentation can be related to gross structural features of the subducting Juan de Fuca plate. The orientation of the volcanic front of segments one and two changes from NW in northern Washington to NE in southern Washington, paralleling the strike of the subducting Juan de Fuca plate. Segments one and two are separated by a 90-km volcanic gap between Mount Rainier and Glacier Peak that is landward of the portion of the subducting plate having the least average dip to a depth of 60 km. A narrow, N-S trending belt of predominantly andesitic vents in Oregon constitutes a third segment, which is landward of the seismically quiet portion of the subduction zone. The narrowness of this segment may indicate steep dip of the subducting plate beneath the Cascade arc in Oregon. Vents are sparse between segment four (containing the Mount Shasta and Medicine Lake centers) and segment five (containing Lassen Peak), where the Juan de Fuca and Gorda North plates are characterized by differing age, amounts of subcrustal seismicity, and probably geometry. From the relation between seismicity at depth of 60 km and the position of the volcanic front of vents formed since 5 Ma, transitions between subducting-plate segments of varying geometry likely occur near boundaries between independently defined volcanic segments in northern Oregon and northern California. In the Basin and Range province east of the Cascade arc, volcanism migrated into the region adjacent to the Cascade Range during the interval 5–10 Ma. Since 5 Ma, the impingement of the two provinces is characterized by cessation of basin-range volcanism in southern Oregon, continuation of basaltic volcanism in northeastern California where the impingement process may not yet be complete, and contraction of the area of mafic volcanism around Mount Shasta, Medicine Lake, and Lassen Peak. In central Oregon where the northern margin of basin-range volcanism (the High Lava Plains) intersects the Cascade arc, impingement of basin-range extensional volcanism approximately coincides in time and space with the development of the High Cascade graben between Three Sisters and Mount Jefferson.

Journal of Geophysical Research Solid Earth↗

USGS1975

Silurian and Devonian miogeosynclinal and transitional rocks of the Fish Creek Reservoir window, central Idaho

Documentation of Devonian continental-shelf shallow-water carbonate rocks in the core of the Fish Creek Reservoir window shifts the known westernmost limit of the Devonian miogeosyncline 50 km (30 mi) southwest across the structural grain from the well-known miogeosynclinal sequence in the Lost River Range. The miogeosynclinal carbonate sequence in the window has a minimum thickness of 450 m (1,500 ft). It comprises the upper Lower Devonian (Emsian) and lower Middle Devonian (Eifelian) Carey Dolomite (new), the upper Middle Devonian (Givetian) and Upper Devonian Jefferson Formation, and the Upper Devonian Picabo Formation (new). Conodont faunas precisely date the Carey. The Picabo Formation, composed of interbedded sandy dolomite-pebble conglomerate and dolomitic quartzose sandstone, is unlike any previously described formation of Late Devonian or Early Mississippian age in central Idaho. It resembles parts of the Stansbury, Beirdneau, Leatham, and Victoria Formations, which reflect areas of local Late Devonian uplift and erosion of older shelf rocks in northern Utah and southeastern Idaho. Transitional (continental-slope) rocks of the Roberts Mountains Formation representing reef and offreef facies are thrust over the Devonian shelf sequence within the Fish Creek Reservoir window. The Roberts Mountains Formation here is precisely dated as latest Silurian (Pridolian, eosteinhornensis Zone) through earliest Devonian (Lochkovian) by a sequence of conodont faunas. The easternmost known exposures of possible Devonian siliceous facies rocks assigned to the Milligen(?) Formation are present less than 4.8 km (3 mi) southwest of the shelf sequence. Structural relations and paleotectonic reconstructions suggest that they have a minimum eastward translation of 32 km (20 mi). The Devonian continent-ocean basin interface, along which the Antler orogenic belt developed at this latitude, probably was located near the east edge of the present Idaho batholith.

Idaho↗

USGS2016

Simulated impacts of climate change on phosphorus loading to Lake Michigan

Phosphorus (P) loading to the Great Lakes has caused various types of eutrophication problems. Future climatic changes may modify this loading because climatic models project changes in future meteorological conditions, especially for the key hydrologic driver — precipitation. Therefore, the goal of this study is to project how P loading may change from the range of projected climatic changes. To project the future response in P loading, the HydroSPARROW approach was developed that links results from two spatially explicit models, the SPAtially Referenced Regression on Watershed attributes (SPARROW) transport and fate watershed model and the water-quantity Precipitation Runoff Modeling System (PRMS). PRMS was used to project changes in streamflow throughout the Lake Michigan Basin using downscaled meteorological data from eight General Circulation Models (GCMs) subjected to three greenhouse gas emission scenarios. Downscaled GCMs project a + 2.1 to + 4.0 °C change in average-annual air temperature (+ 2.6 °C average) and a − 5.1% to + 16.7% change in total annual precipitation (+ 5.1% average) for this geographic area by the middle of this century (2045–2065) and larger changes by the end of the century. The climatic changes by mid-century are projected to result in a − 21.2% to + 8.9% change in total annual streamflow (− 1.8% average) and a − 29.6% to + 17.2% change in total annual P loading (− 3.1% average). Although the average projected changes in streamflow and P loading are relatively small for the entire basin, considerable variability exists spatially and among GCMs because of their variability in projected future precipitation.

Lake Michigan↗

USGS2017

Effects of tow transit on the efficacy of the Chicago Sanitary and Ship Canal Electric Dispersal Barrier System

In 2016, the U.S. Fish and Wildlife Service, U.S. Geological Survey, and U.S. Army Corps of Engineers undertook a field study in the Chicago Sanitary and Ship Canal near Romeoville, Illinois to determine the influence of tow transit on the efficacy of the Electric Dispersal Barrier System (EDBS) in preventing the passage of juvenile fish (total length < 100 millimeters (mm)). Dual-frequency identification sonar data showed that large schools of juvenile fish (mean school size of 120 fish; n = 19) moved upstream and crossed the electric field of an array in the EDBS concurrent with downstream-bound (downbound) loaded tows in 89.5% of trials. Smaller schools of juvenile fish (mean school size of 98 fish; n = 15) moved downstream and crossed the electric field of an array in the EDBS concurrent with upstream-bound (upbound) loaded tows in 73.3% of trials. Observed fish passages through the EDBS were always opposite to the direction of tow movement, and not associated with propeller wash. These schools were not observed to breach the EDBS in the absence of a tow and showed no signs of incapacitation in the barrier during tow passage. Loaded tows transiting the EDBS create a return current of water flowing between the tow and the canal wall that typically travels opposite the direction of tow movement, and cause a decrease in the voltage gradient of the barrier of up to 88%. Return currents and decreases in voltage gradients induced by tow passage likely contributed to the observed fish passage through the EDBS. The efficacy of the EDBS in preventing the passage of small, wild fish is compromised while tows are moving across the barrier system. In particular, downbound tows moving through the EDBS create a pathway for the upstream movement of small fish, and therefore may increase the risk of transfer of invasive fishes from the Mississippi River Basin to the Great Lakes Basin.

Illinois↗

USGS2011

Lunar mare deposits associated with the Orientale impact basin: New insights into mineralogy, history, mode of emplacement, and relation to Orientale Basin evolution from Moon Mineralogy Mapper (M3) data from Chandrayaan-1

Moon Mineralogy Mapper (M3) image and spectral reflectance data are combined to analyze mare basalt units in and adjacent to the Orientale multiring impact basin. Models are assessed for the relationships between basin formation and mare basalt emplacement. Mare basalt emplacement on the western nearside limb began prior to the Orientale event as evidenced by the presence of cryptomaria. The earliest post-Orientale-event mare basalt emplacement occurred in the center of the basin (Mare Orientale) and postdated the formation of the Orientale Basin by about 60-100 Ma. Over the next several hundred million years, basalt patches were emplaced first along the base of the Outer Rook ring (Lacus Veris) and then along the base of the Cordillera ring (Lacus Autumni), with some overlap in ages. The latest basalt patches are as young as some of the youngest basalt deposits on the lunar nearside. M3 data show several previously undetected mare patches on the southwestern margins of the basin interior. Regardless, the previously documented increase in mare abundance from the southwest toward the northeast is still prominent. We attribute this to crustal and lithospheric trends moving from the farside to the nearside, with correspondingly shallower density and thermal barriers to basaltic magma ascent and eruption toward the nearside. The wide range of model ages for Orientale mare deposits (3.70-1.66 Ga) mirrors the range of nearside mare ages, indicating that the small amount of mare fill in Orientale is not due to early cessation of mare emplacement but rather to limited volumes of extrusion for each phase during the entire period of nearside mare basalt volcanism. This suggests that nearside and farside source regions may be similar but that other factors, such as thermal and crustal thickness barriers to magma ascent and eruption, may be determining the abundance of surface deposits on the limbs and farside. The sequence, timing, and elevation of mare basalt deposits suggest that regional basin-related stresses exerted control on their distribution. Our analysis clearly shows that Orientale serves as an excellent example of the early stages of the filling of impact basins with mare basalt. Copyright ?? 2011 by the American Geophysical Union.

Journal of Geophysical Research E: Planets↗

USGS2019

Resurgence of cisco (Coregonus artedi) population levels in Lake Michigan

In recent decades, many factors that were linked with the decline of Great Lakes cisco ( Coregonus artedi ) populations have subsided. The goal of this study was to investigate where cisco exist in Lake Michigan and evaluate evidence for recovery including when, where, and to what extent it is occurring. We evaluated datasets from several independent monitoring efforts that did and did not target cisco. We also evaluated trends in commercial and recreational catches of cisco. Across these datasets, there was strong evidence of a sustained recovery of cisco stocks that began in Lake Michigan in the mid-2000s. Fall gill net surveys and commercial fisheries provided reasonable indications of a population recovery in the northeast by 2011. Further south, Ludington Pump Storage barrier net monitoring also recorded increasing numbers of cisco starting in 2011. Recreational harvest estimates were valuable in evaluating spatial distributions but were less valuable as an early signal of abundance shifts. Measures of the recreational harvest of cisco most notably increased in 2014. The highest catch rates and harvest occurred in Grand Traverse Bay and northern Lake Michigan as evidenced by recreational, commercial, and fall netting surveys. Observations of cisco are expanding and have increased in intensity along the eastern shore of Lake Michigan south to Muskegon in both fishery dependent and independent surveys. The similarity in trends from all data sources indicate that cisco abundance has increased, and their range within the basin continues to expand.

Michigan↗

USGS2002

Foraging locations of double-crested cormorants on western Lake Erie: Site characteristics and spatial associations with prey fish densities

Radio-tagged double-crested cormorants ( Phalacrocorax auritus ) nesting on Middle Island, Ontario and unmarked cormorants in the western basin of Lake Erie were monitored in 1999. Radio-tagged cormorants were located by aircraft and by boat along regular survey routes. In addition, foraging flocks of radio-tagged and unmarked cormorants were located during the boat surveys. Approximately 79% of foraging radio-tagged individuals, and approximately 65% of all foraging flocks were observed within 2.5 km of shore. These percentages were greater than expected, based on the percentage of the area of water within 2.5 km of shore. All size classes of flocks examined were found more frequently than expected on water ≤10 m deep. Trawling data collected annually from 1988 to 1999 during the month of August were used to determine the historical distributions of the four fish species found to comprise the majority of the diet of cormorants in the area. August corresponded to a period when there is maximal overlap in the diets of cormorants and walleye ( Stizostedion vitreum ) in the area and when the number of foraging cormorants in the area is large. Flocks of cormorants of all size classes examined were not found proportionately more in regions that contained higher than the historical median annual catches of any of the four prey species. These results, coupled with previous bioenergetics studies, suggest that the impact of cormorants on the fishery of the western basin of Lake Erie is localized with respect to depth and distance from shore.

Journal of Great Lakes Research↗

USGS2004

Contemporary tectonic deformation of the Basin and Range province, western United States: 10 years of observation with the Global Positioning System

[1] We have estimated patterns and rates of crustal movement across 800 km of the Basin and Range at ∼39° north latitude with Global Positioning System surveys in 1992, 1996, 1998, and 2002. The total rate of motion tangent to the small circle around the Pacific‐North America pole of rotation is 10.4 ± 1.0 mm/yr, and motion normal to this small circle is 3.9 ± 0.9 mm/yr compared to the east end of our network. On the Colorado Plateau the east end of our network moves by ∼1–2 mm/yr westerly with respect to North America. Transitions in strain rates delimit six major tectonic domains within the province. These deformation zones coincide with areas of modern seismicity and are, from east to west, (1) east‐west extension in the Wasatch Fault zone, (2) low rate east‐west extension centered near the Nevada‐Utah border, (3) low rate east‐west contraction between 114.7°W and 117.9°W, (4) extension normal to and strike‐slip motion across the N10°E striking Central Nevada Seismic Zone, (5) right lateral simple shear oriented N13°W inside the Walker Lane Belt, and (6) shear plus extension near the Sierra Nevada frontal faults. Concentration of shear and dilatational deformation across the three westernmost zones suggests that the Walker Lane Belt lithosphere is rheologically weak. However, we show that linear gradients in viscosity and gravitational potential energy can also effectively concentrate deformation. In the Basin and Range, gradients in gravitational potential are spatially anticorrelated with dilatational strain rates, consistent with the presence of horizontal variations in viscosity of the lithosphere.

Arizona, California, Nevada, Utah↗

USGS1978

Phosphorus in hydrothermal waters of Yellowstone National Park, Wyoming

Ninety-seven hot-spring and geyser samples (field acidified to pH<1.4 with HCl or HNO 3 ) from Yellowstone National Park, Wyo., were analyzed for PO 4 -P using reduced molybdenum-blue and the selective arsenate reducing agent, metabisulfite-thiosulfate. The PO 4 -P concentrations ranged from below detection limit (~1-73 micrograms per liter). Twenty-five springs had PO 4 -P concentrations exceeding 6.8 μ g/L; seven spring samples exceeded 20 μg/L. Elevated PO 4 -P contents were invariably associated with mixed springs, as evidenced by diluted chloride concentrations and, commonly, subboiling temperatures, low pH's, and elevated calcium concentrations. Alkaline high-chloride (>400 milligrams per liter) hydrothermal waters from Upper and Norris Geyser Basins had PO 4 -P concentrations below 2 μg/L and represent the low end of the range of PO 4 -P contents in natural waters.

Wyoming↗

USGS2026

Biological, environmental, and geomorphological factors influencing reach-specific survival of spring Chinook Salmon smolts upstream of the Columbia–Snake River hydrosystem

Objective Pacific salmon Oncorhynchus spp. are exhibiting catastrophic declines throughout much of the Pacific Northwest, and juvenile mortality contributions are disproportionately high. Many Pacific salmon smolt populations are exhibiting high natal stream mortality; however, detailed natal stream reach-specific survival knowledge is lacking. Our objectives were to estimate natal stream reach-specific survival and identify influential covariates for spring Chinook Salmon O. tshawytscha smolts. An additional objective was to evaluate (i.e., estimate postrestoration cumulative survival) a novel and strategic large-scale river restoration approach (i.e., stream confluence restoration) in two Pacific Northwest spring Chinook Salmon natal streams. Methods Using radiotelemetry techniques during March–June (2011–2017), we estimated natal stream reach-specific survival for spring Chinook Salmon smolts in Catherine Creek and the Grande Ronde River, northeast Oregon. We examined the interrelated influences of temporal, biological, environmental, and geomorphological covariates on the behavior, travel time, and reach-specific survival of spring Chinook Salmon smolts that were emigrating through two hydrologically altered natal streams in the interior Columbia River basin. For each natal stream smolt tag-group, Cormack–Jolly–Seber reach-specific survival estimates that were adjusted for premature tag failure (i.e., bias-corrected) were generated. Subsequently, smolt effects were estimated using reach-specific travel times and survival estimates coupled with individual time-varying covariates from radio-tagged smolts and occupied reaches using an existing predator–prey model (i.e., mean free-path length [ XT ] model). Complementary population-specific principal coordinate analyses (PCoAs) were conducted to facilitate visualization of multicovariate resemblances in ordination space. Last, we employed our best-fitting XT model to model cumulative changes in smolt survival that were associated with a large-scale stream channel restoration scenario (i.e., restoration of the historical Catherine Creek and Grande Ronde River confluence). Results In aggregate, Catherine Creek smolts exhibited high mortality throughout Catherine Creek but near-100% survival upon entering the Grande Ronde River. In contrast, Grande Ronde River smolts generally exhibited low mortality upstream from the Grande Ronde Valley and high mortality throughout the Grande Ronde Valley. Our best-fitting XT model indicated that smolt survival was positively correlated with discharge, body size, and current velocity but negatively correlated with avian predation. Natural-origin smolts from Catherine Creek displayed higher λ-values (i.e., distance between predator–prey encounters) than their significantly larger and faster emigrating hatchery conspecifics, indicating that hatchery smolts may be more susceptible to predation. Our population-specific PCoAs further revealed that novel water (i.e., unique water chemistry) and emigration rate were the strongest predictors of reach occupancy in multivariate ordination space. Under a stream restoration scenario of restoring the historical hydrological template (i.e., restored channel configuration), our best-fitting XT model predicted changes in population-specific cumulative survivals to the lower Grande Ronde Valley (Imbler, Oregon) ranging from −38.4% to 69.0% for Grande Ronde River and Catherine Creek spring Chinook Salmon smolts, respectively. Conclusions Our best-fitting XT model and PCoAs identified the relative importance of biological, environmental, and geomorphological factors to both natural- and hatchery-origin Chinook Salmon smolt survival in two neighboring interior natal streams in the Columbia River basin. Our research indicates that concurrent habitat restoration and fish management strategies, including focused attention on smolt-rearing nursery habitat restoration, piscivorous avian control plans, adaptive management strategies for hatchery smolt releases, and discharge and novel water regime restoration projects, may yield survival benefits to “in-basin” Chinook Salmon smolts. Our research can inform origin-type-specific Chinook Salmon smolt management, habitat restoration, and future research decisions throughout the upper Grande Ronde River subbasin and potentially the Pacific Northwest.

Oregon, Washington↗

USGS1983

Additions of nutrients and major ions by the atmosphere and tributaries to nearshore waters of northwestern Lake Huron

Nutrient additions by the atmosphere and six tributaries to nearshore waters of northwestern Lake Huron were measured at weekly intervals from August 1975 to July 1976. The atmosphere contributed 43% of the nitrogen (N) and 10% of the phosphorus (P) that was added during the year. The 1975–76 atmospheric loading rate of total N to this area (11 kg/ha/yr) was one of the highest found to date in the United States. N was conserved more efficiently than P in the tributary drainage basins. Of the N and P that fell annually on the watersheds under study, 2 to 37% of the N and 31 to 84% of the P was carried with runoff to the lake. From a basin where ditching and clear-cutting occurred, water, P, silica (SiO 2 ), N, and sodium were lost at higher rates than from five other basins. Most of the N in bulk atmospheric samples (23%) and tributary waters (56%) was dissolved organic N, a form of N not often measured.

Michigan↗

USGS2012

A review of the regional geophysics of the Arizona Transition Zone

A review of existing geophysical information and new data presented in this special section indicate that major changes in crustal properties between the Basin and Range and Colorado Plateau occur in, or directly adjacent to, the region defined as the Arizona Transition Zone. Although this region was designated on a physiographic basis, studies indicate that it is also the geophysical transition between adjoining provinces. The Transition Zone displays anomalous crustal and upper mantle seismic properties, shallow Curie isotherms, high heat flow, and steep down-to-the-plateau Bouguer gravity gradients. Seismic and gravity studies suggest that the change in crustal thickness, from thin crust in the Basin and Range to thick crust in the Colorado Plateau, may occur as a series of steps rather than a planar surface. Anomalous P wave velocities, high heat flow, shallow Curie isotherms, and results of gravity modeling suggest that the upper mantle is heterogeneous in this region. A relatively shallow asthenosphere beneath the Basin and Range and Transition Zone contrasted with a thick lithosphere beneath the Colorado Plateau would be one explanation that would satisfy these geophysical observations.

Journal of Geophysical Research↗

USGS1995

A selected bibliography of water-related research in the upper Klamath Basin, Oregon

A bibliography containing 165 selected references was compiled to assist local, State, and Federal agencies that have ongoing water-related research interests in the Upper Klamath Basin. The report has two parts. Part 1 is a list of bibliographic citations alphabetized by author, and Part 2 is a subject index that references bibliographic entries. Categories of the subject index include chemistry, ecology, geology, hydrology, land use, and water management related reports. Maps, reports, proposals, theses, dissertations, and journal articles are referenced. Some of the environmental issues addressed by references in the bibliography are hypereutrophication, nuisance algal blooms, endangered fish species, water allocation questions, wetland and riparian habitat restoration, and pesticide and fertilizer utilization.

Open-File Report↗

USGS2007

Distribution and abundance of burrowing mayflies ( Hexagenia spp.) in Lake Erie, 1997-2005

Burrowing mayflies ( Hexagenia limbata and H. rigida ) recolonized sediments of the western basin of Lake Erie in the 1990s following decades of pollution abatement. We predicted that Hexagenia would also disperse eastward or expand from existing localized populations and colonize large regions of the other basins. We sampled zoobenthos in parts of the western and central basins yearly from 1997–2005, along the north shore of the eastern basin in 2001–2002, and throughout the lake in 2004. In the island area of the western basin, Hexagenia was present at densities ≤1,278 nymphs/m 2 and exhibited higher densities in odd years than even years. By contrast, Hexagenia became more widespread in the central basin from 1997–2000 at densities ≤48 nymphs/m 2 but was mostly absent from 2001–2005. Nymphs were found along an eastern basin transect at densities ≤382/m 2 in 2001 and 2002. During the 2004 lake-wide survey, Hexagenia was found at 63 of 89 stations situated throughout the western basin (≤1,636 nymphs/m 2 , mean = 195 nymphs/m 2 , SE = 32, N = 89) but at only 7 of 112 central basin stations, all near the western edge of the basin (≤708 nymphs/m 2 ), and was not found in the eastern basin. Hexagenia was found at 2 of 62 stations (≤91 nymphs/m 2 ) in harbors, marinas, and tributaries along the south shore of the central basin in 2005. Oxygen depletion at the sediment-water interface and cool temperatures in the hypolimnion are probably the primary factors preventing successful establishment throughout much of the central basin. Hexagenia can be a useful indicator of lake quality where its distribution and abundance are limited by anthropogenic causes.

Journal of Great Lakes Research↗

USGS1997

Isotopic and trace element compositions of upper mantle and lower crustal xenoliths, Cima volcanic field, California: Implications for evolution of the subcontinental lithospheric mantle

Ultramafic and mafic xenoliths from the Cima volcanic field, southern California, provide evidence of episodic modification of the upper mantle and underplating of the crust beneath a portion of the southern Basin and Range province. The upper mantle xenoliths include spinel peridotite and anhydrous and hydrous pyroxenite, some cut by igneous-textured pyroxenite-gabbro veins and dikes and some by veins of amphibole ?? plagioclase. Igneous-textured pyroxenites and gabbros like the dike rocks also occur abundantly as isolated xenoliths inferred to represent underplated crust. Mineral and whole rock trace element compositions among and within the different groups of xenoliths are highly variable, reflecting multiple processes that include magma-mantle wall rock reactions, episodic intrusion and it filtration of basaltic melts of varied sources into the mantle wall rock, and fractionation. Nd, Sr, and Pb isotopic compositions mostly of clinopyroxene and plagioclase mineral separates show distinct differences between mantle xenoliths (??Nd = -5.7 to +3.4; 87Sr/86Sr = 0.7051 - 0.7073; 206Pb/204Pb = 19.045 - 19.195) and the igneous-textured xenoliths (??Nd = +7.7 to +11.7; 87Sr/86Sr = 0.7027 - 0.7036 with one carbonate-affected outlier at 0.7054; and 206Pb/204Pb = 18.751 - 19.068), so that they cannot be related. The igneous-textured pyroxenites and gabbros are similar in their isotopic compositions to the host basaltic rocks, which have ??Nd of+5.1 to +9.3; 87Sr/86Sr of 0.7028 - 0.7050, and 206Pb/204Pb of 18.685 - 21.050. The igneous-textured pyroxenites and gabbros are therefore inferred to be related to the host rocks as earlier cogenetic intrusions in the mantle and in the lower crust. Two samples of peridotite, one modally metasomatized by amphibole and the other by plagioclase, have isotopic compositions intermediate between the igneous-textured xenoliths and the mantle rock, suggesting mixing, but also derivation of the metasomatizing magmas from two separate and distinct sources. Sm-Nd two-mineral "isochrons" yield apparent ages for petrographically identical rocks believed to be coeval ranging from -0 to 113 ?? 26 Ma, indicating the unreliability of dating these rocks with this method. Amphibole and plagioclase megacrysts are isotopically like the host basalts and probably originate by mechanical breakup of veins comagmatic with the host basaltic rocks. Unlike other Basin and Range localities, Cima Cr-diopside group isotopic compositions do not overlap with those of the host basalts. Copyright 1997 by the American Geophysical Union.

Journal of Geophysical Research B: Solid Earth↗