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USGS1987

Morphology and evolutionary significance of Adoneis pacifica gen. et sp. Nov. (Fragilariaceae, Bacillariophyta), a marine araphid diatom from Chile

A new marine diatom genus and species, Adoneis pacifica G.W. Andrews and P. Rivera, has been identified in Chilean coastal waters. This taxon shows obvious affinities to the genera Rhaphoneis and Delphineis , but cannot be classified in either, as they are currently construed. Adoneis pacifica resembles Rhaphoneis in outline and to some degree in the pseudocelli, whereas it resembles Delphineis in the structure of the vela and the positioning of the apical rimoportulae. However, distinctive characters of this new monotypic genus are: (1) the usual positioning of a single rimoportula near the centre of each lateral margin of the valve, and (2) the occurrence of well organized apical pore fields (pseudocelli), in which the pores are much smaller than elsewhere on the valve. These appear to be primitive traits for the araphid diatom family Fragilariaceae, and they suggest that Adoneis pacifica may be a conservative species important in the study of the evolution of the family.

Diatom Research↗

USGS1996

Trace fossils from Jurassic lacustrine turbidites of the Anyao Formation (Central China) and their environmental and evolutionary significance

The Lower Jurassic Anyao Formation crops out near Jiyuan city, western Henan Province, central China. It is part of the infill of the nonmarine early Mesozoic Jiyuan‐Yima Basin. In the Jiyuan section, this unit is about 100 m thick and consists of laterally persistent, thin and thick‐bedded turbidite sandstones and mudstones displaying complete and base‐or top‐absent Bouma sequences, and thick‐bedded massive sandstones. The Anyao Formation records sedimentation within a lacustrine turbidite system developed in a pull‐apart basin. Processes involved include high and low density turbidity currents, sometimes affected by liquefaction or fluidization. Facies analysis suggests that this succession is formed by stacked aggradational turbidite lobes. The absence of thick mudstone packages indicates that background sedimentation was subordinate to high frequency turbidite deposition. The Anyao Formation hosts a moderately diverse ichnofauna preserved as hypichnial casts on the soles of thin‐bedded turbidite sandstones. The ichnofauna consists of Cochlichnus anguineus, Hel‐minthoidichnites tenuis, Helminthopsis abeli, H. hieroglyphica, Mono‐morphichnus lineatus, Paracanthorhaphe togwunia, Tuberculichnus vagans, Vagorichnus anyao, tiny grazing trails, and irregularly branching burrows. Vagorichnus anyao occurs not only as a discrete trace, but also as a compound ichnotaxon intergrading with Gordia marina and Tuberculichnus vagans. Both predepositional and post‐depositional traces are present on the soles of turbidites. This ichnofauna comprises both feeding and grazing traces produced by a deposit‐feeding lacustrine benthic biota. Crawling traces are rare. Although certain ichnofossils (e.g. V. anyao, P. togwunia) show overall similarities with deep‐sea agrichnia, they differ in reflecting remarkably less specialized feeding strategies, displaying overcrossing between specimens (and to a lesser extent, self‐crossing), and in the case of V’ anyao recording post‐turbidite burrowing activity. The development of less specialized strategies than those displayed by deep‐marine ichnofaunas may be related to less stable conditions, typical of lake settings. Oxyenation, energy, sedimentation rate (both event and background), food supply, soft‐sediment deformation and erosion rate have mainly influenced trace‐fossil distribution. Turbidity currents would have ensured oxygen (as well as food) supply to deep lake settings, thus allowing the establishment of a moderately diverse biota. Biogenic structures were mostly confined to the outer, low energy areas. High sedimentation rates and strong erosion precluded preservation of ichnofossils in inner lobe settings. The Anyao ichnofauna is of significance in furthering knowledge of the colonization of deep lakes throughout the stratigraphie record and in identification of additional nonmarine ichnofacies. The ana‐lyzed ichnofauna resembles late Paleozoic lacustrine assemblages described from different localities around the world and is regarded as a Mesozoic example of the Mermia ichnofacies. However, when compared with Paleozoic assemblages, the Anyao ichnofauna shows a clear dominance of burrows over surface trails, deeper burrowing penetration, larger size, and presence of relatively more complex structures. The high burrow/surface trail ratio may be indicative of lower preservation potential in the latter, thus reflecting a tap‐honomic overprint. In contrast to the Paleozoic examples, the establishment of a relatively well‐developed lacustrine infauna may have precluded preservation of surface trails. Burrower activity probably obliterated biogenic structures formed close to the sediment‐water interface.

Ichnos: An International Journal for Plant and Ani↗

USGS2000

A new ichnospecies of Nereites from carboniferous tidal-flat facies of eastern Kansas, USA: Implications for the Nereites-Neonereites debate

Predominantly horizontal, gently curved to slightly sinuous traces constituting uniserial rows of imbricated, subspherical sediment pads occur in Pennsylvanian tidal-flat facies of eastern Kansas. These traces exhibit a complex, actively filled internal structure. The presence of a median tunnel enveloped by overlapping pads of reworked sediment indicates that these biogenic structures should be included in the ichnogenus Nereites MacLeay in Murchison, 1839. A new ichnospecies, N. imbricata , is erected. Externally, Nereites imbricata differs from the other Nereites ichnospecies by the large, tightly packed, imbricated pads that commonly result in an annulated appearance on bedding-planes. Internally, obliquely arranged, arcuate laminae envelope the median tunnel and tend to follow the outline of the external semispherical pads. Additionally, the behavioral pattern reflected by N. imbricata is less specialized than that of the other Nereites ichnospecies. Eione monoliformis Tate, 1859 resembles N. imbricata in general appearence, but lack the diagnostic Nereites internal structure, and is invariably preserved as positive epireliefs. Occurrence of Nereites imbricata as both median tunnels surrounded by reworked sediment ( Nereites preservation) and uniserial rows of imbricated sediment pads ( Neonereites preservation) supports the notion that Neonereites Seilacher, 1960 is a preservational variant of Nereites . The ichnogenus Nereites is an eurybathic form and is a common component of Paleozoic shallow-marine facies.

Kansas↗

USGS2022

A phylogeny based on cytochrome-c oxidase gene sequences identifies sympatric Ichthyophonus genotypes in the NE Pacific Ocean

ABSTRACT: In recent decades, evidence has accumulated to suggest that the widespread and highly variable parasite Ichthyophonus hoferi is actually a species complex. Highly plastic morphology and a general lack of defining structures has contributed to the likely underestimate of biodiversity within this group. Molecular methods are a logical next step in the description of these parasites, but markers used to date have been too conserved to resolve species boundaries. Here we use mitochondrial encoded cytochrome-c oxidase (MTCO1) gene sequences and phylogenic analysis to compare Ichthyophonus spp. isolates from several marine and anadromous fish hosts. The resulting phylogeny displays lineage separation among isolates and possible host/niche segregation not previously described. The parasite type that infects Pacific herring Clupea pallasii , Atlantic herring C. harengus , Atlantic salmon Salmo salar , and Pacific staghorn sculpin Oligocottus maculosus (Clade A) is different from that which infects Chinook salmon Oncorhynchus tshawytscha, walleye pollock Gadus chalcogrammus , Greenland halibut Reinhardtius hippoglossoides , and Pacific halibut Hippoglossus stenolepsis (Clade B). MTCO1 sequences confirmed the presence of a more divergent Ichthyophonus sp. isolated from American shad Alosa sapidissima in rivers of eastern North America (Clade C), while American shad introduced to the Pacific Ocean are infected with the same parasite that infects Pacific herring (Clade A). Currently there are no consensus criteria for delimiting species within Ichthyophonidae , but MTCO1 sequences hold promise as a potential species identifying marker and useful epizootiological tool.

Diseases of Aquatic Organisms↗

USGS2011

An open-water electrical geophysical tool for mapping sub-seafloor heavy placer minerals in 3D and migrating hydrocarbon plumes in 4D

A towed-streamer technology has been developed for mapping placer heavy minerals and dispersed hydrocarbon plumes in the open ocean. The approach uses induced polarization (IP), an electrical measurement that encompasses several different surface-reactive capacitive and electrochemical phenomena, and thus is ideally suited for mapping dispersed or disseminated targets. The application is operated at sea by towing active electrical geophysical streamers behind a ship; a wide area can be covered in three dimensions by folding tow-paths over each other in lawn-mower fashion. This technology has already been proven in laboratory and ocean settings to detect IP-reactive titanium- and rare-earth (REE) minerals such as ilmenite and monazite. By extension, minerals that weather and accumulate/concentrate by a similar mechanism, including gold, platinum, and diamonds, may be rapidly detected and mapped indirectly- even when dispersed and covered with thick, inert sediment. IP is also highly reactive to metal structures such as pipelines and cables. Currently, the only means for mapping an oil-spill plume is to park a large ship in the ocean and drop a sampling string over the side, requiring hours of time per sampling point. The samples must then be chemically analyzed, adding additional time and expense. We believe that an extension of the marine IP technology could also apply to rapidly mapping both seafloor- blanket and disseminated hydrocarbon plumes in the open ocean, as hydrocarbon droplets in conductive seawater are topologically equivalent to a metal-plates-and-dielectric capacitor. Because the effective capacitance would be frequency-dependent on droplet size, the approach we advocate holds the potential to not only map, but also to characterize the evolution and degradation of such a plume over time. In areas where offshore oil field development has been practiced for extended periods, making IP measurements from a towed streamer may be useful for locating buried - nd exposed pipelines, as well as pipeline leaks. We believe this technique will be a more cost-effective method than drop-sampling to map and monitor hydrocarbon plumes in open ocean settings. A marine induced polarization system was used successfully to map a 15 km × 45 km swath of the ocean floor off eastern South Africa with 3-meter sampling along 200-meter-separated profiles. The survey detected titanium-bearing sands up to 15 meters below the seafloor. From preliminary laboratory work it is apparent that we can extend this technology to monitor significant environmental problems including anthropogenic and industrial waste washed into sensitive estuaries and sounds during storm-water runoff episodes, and also to map and characterize dispersed oil plumes in the seawater column in three dimensions, as well as movement and dispersal of both over time.

Conference Paper↗

USGS2002

Petroleum geology and total petroleum systems of the Widyan Basin and Interior Platform of Saudi Arabia and Iraq

Two total petroleum systems are associated with the Widyan Basin - Interior Platform Province in northern Saudi Arabia and western Iraq. In the Paleozoic Qusaiba/Akkas/Abba/ Mudawwara Total Petroleum System, which consists of one assessment unit - the Horst/Graben-Related Oil and Gas Assessment Unit - high-gravity, low-sulfur crude oil, as well as natural gas, occurs in horst/graben-related traps that formed prior to, during, and after Hercynian deformation (Carboniferous). The source of oil and gas is from organic-rich marine shale at the base of the Silurian sedimentary sequence (Qusaiba, Akkas, Mudawwara, and Abba Formations) that was deposited under dysoxic to anoxic conditions in an intra-shelf basin located north of the Central Arabian Arch. Onset of oil generation in Iraq began about 250 million years ago (Ma) and in eastern Saudi Arabia about 160 Ma, reaching peak generation, expulsion, migration, and entrapment during the Jurassic Period. In Saudi Arabia, petroleum migrated into fluvial and eolian quartzose sandstones of the Carboniferous-Early Permian Unayzah Formation that overlies the Hercynian unconformity, filling in rifts and half-grabens to thicknesses ranging to more than 400 meters. Combined stratigraphic-structural traps exist where the Unayzah Formation is the reservoir, as is the case in central Saudi Arabia. Oil and gas are sealed in those reservoirs by overlying tight carbonate- evaporite strata, and by subunconformity pinchouts of Pre-Unayzah clastic reservoir units against impermeable facies. In Iraq, reservoirs are sandstones of the Ordovician Upper Khabour and Silurian Akkas Formations. Over most of the Southwestern Desert of Iraq, Lower Silurian shale is a seal for hydrocarbons in the underlying Ordovician Khabour Formation. The Jurassic Gotnia/Barsarin/Sargelu/Najmah Total Petroleum System has two assessment units: the Platform Horst/Graben- Related Oil Assessment Unit and the Basinal Oil and Gas Assessment Unit. All reservoirs are in the Upper Jurassic Najmah Limestone and Gotnia Formation in Iraq, and the correlative Arab Formation in Saudi Arabia, occurring as lenses of marine bar or shelf-margin calcarenites, calcarenitic limestone, and dolomite. These strata grade eastward into organic-rich source rocks that were deposited under anoxic and dysoxic conditions in three restricted intra-shelf basins - from north to south, the Gotnia, Arabian, and Southern Arabian Gulf Basins. Maturation of the Upper Jurassic source-rock formations (Sargelu and Naokelekan Formations in Iraq) began around 90 Ma; peak generation took place from 85 to 13 Ma. With time, the oil migrated updip and was trapped in calcarenite lenses. Later, oil remigrated and was trapped in anticlines that began to form in Early Cretaceous time. Younger Jurassic shale and anhydrite seal rocks are distributed throughout the total petroleum system. The Widyan Basin-Interior Platform Province (2023) ranks 17th in the world, exclusive of the United States, with 62.5 billion barrels of oil equivalent of total petroleum endowment (cumulative production plus remaining petroleum plus estimated mean undiscovered volumes). Mean estimates of undiscovered petroleum for the province, which includes both Paleozoic and Jurassic petroleum systems as well as portions of three additional total petroleum systems from adjacent provinces, are 21.22 billion barrels of oil, 94.75 trillion cubic feet of gas (15.8 billion barrels of oil equivalent), and 6.85 billion barrels of natural gas liquids. The Paleozoic total petroleum system is dominantly gas prone, whereas the volumetrically larger Jurassic total petroleum system is oil prone - resulting in the characterization of the province as an oil province. The discovery maturity for the province is a relatively low 31 percent, meaning that much of the province petroleum potential lies in the future.

Arabian Peninsula↗

USGS2014

Aquaculture disturbance impacts the diet but not ecological linkages of a ubiquitous predatory fish

Aquaculture operations are a frequent and prominent cause of anthropogenic disturbance to marine and estuarine communities and may alter species composition and abundance. However, little is known about how such disturbances affect trophic linkages or ecosystem functions. In Puget Sound, Washington, aquaculture of the Pacific geoduck clam ( Panopea generosa ) is increasing and involves placing nets and polyvinyl chloride (PVC) tubes in intertidal areas to protect juvenile geoducks from predators. Initial studies of the structured phase of the farming cycle have documented limited impacts on the abundance of some species. To examine the effect of geoduck aquaculture on ecological linkages, the trophic relationships of a local ubiquitous consumer, Pacific staghorn sculpin ( Leptocottus armatus ), to its invertebrate prey were compared between geoduck aquaculture sites and nearby reference areas with no aquaculture. Mark-recapture data indicated that sculpin exhibit local site fidelity to cultured and reference areas. The stomach contents of sculpin and stable isotope signatures of sculpin and their prey were examined to study the trophic ecology of cultured and reference areas. Results showed that the structured phase of geoduck aquaculture initiated some changes to staghorn sculpin ecology, as reflected in sculpin diet through stomach content analysis. However, carbon and nitrogen stable isotopes revealed that the general food web function of sculpin remained unchanged. The source of carbon at the base of the food web and the trophic position of sculpin were not impacted by geoduck aquaculture. The study has important implications for geoduck aquaculture management and will inform regulatory decisions related to shellfish aquaculture policy.

Washington↗

USGS1998

40Ar/39Ar age of the Manson impact structure, Iowa, and correlative impact ejecta in the Crow Creek member of the Pierre Shale (Upper Cretaceous), South Dakota and Nebraska

A set of 34 laser total-fusion 40 Ar/ 39 Ar analyses of sanidine from a melt layer in crater-fill deposits of the Manson impact structure in Iowa has a weighted-mean age of 74.1 ± 0.1 Ma. This age is about 9.0 m.y. older than 40 Ar/ 39 Ar ages of shocked microcline from the Manson impact structure reported previously by others. The 74.1 Ma age of the sanidine, which is a melt product of Precambrian microcline clasts, indicates that the Manson impact structure played no part in the Cretaceous-Tertiary (K-T) mass extinction at 64.5 Ma. Moreover, incremental-heating 40 Ar/ 39 Ar ages of the sanidine show that it is essentially free of excess 40 Ar and has not been influenced by postcrystallization heating or alteration. An age spectrum of the matrix of the melt layer shows effects of 39 Ar recoil, including older ages in the low-temperature increments and younger ages in the high-temperature increments. At 17 places in eastern South Dakota and Nebraska, shocked quartz and feldspar grains are concentrated in the lower part of the Crow Creek Member of the Pierre Shale (Upper Cretaceous). The grains are largest (3.2 mm) in southeastern South Dakota and decrease in size (0.45 mm) to the northwest, consistent with the idea that the Manson impact structure was their source. The ubiquitous presence of shocked grains concentrated in a thin calcarenite at the base of the Crow Creek Member suggests it is an event bed recording an instant of geologic time. Ammonites below and above the Crow Creek Member limit its age to the zone of Didymoceras nebrascense of earliest late Campanian age. Plagioclase from a bentonite bed in this zone in Colorado has a 40 Ar/ 39 Ar age of 74.1 ± 0.1 Ma commensurate with our sanidine age of 74.1 Ma for the Manson impact structure. 40 Ar/ 39 Ar ages of bentonite beds below and above the Crow Creek are consistent with our 74.1 ± 0.1 Ma age for the Manson impact structure and limit its age to the interval ±74.5 0.1 to 73.8 ± 0.1 Ma. Recently, two origins for the Crow Creek have been proposed—eastward transgression of the Late Cretaceous sea and a Manson impact-triggered tsunami. We conclude that most data are in accord with an impact origin for the Crow Creek Member and are at odds with the marine transgression hypothesis.

Iowa, Nebraska, South Dakota↗

USGS1964

Subsurface geology of the upper Cretaceous Kirtland and Fruitland formations of the San Juan Basin, New Mexico and Colorado

The San Juan Basin is an asymmetrical structural basin in northwestern New Mexico and southwestern Colorado. The basin contains sedimentary rocks ranging from Cambrian through Recent in age and attaining a maximum thickness between 14,000 and 15,000 feet. The Upper Cretaceous sedimentary rocks exceed 8,000 feet in thickness and can be divided into two groups: the lower Upper Cretaceous which is composed of the non marine and non-marine rocks and the upper Upper Cretaceous which is composed of the non-marine Kirtland and Fruitland Formations. The Kirtland Shale is subdivided into the lower shale, Farmington Sandstone, and upper shale members. The rocks of the Kirtland and Fruitland Formations consist of fluviatile and flood plain deposits and range in thickness from 1750 feet in the northwest part of the basin to 0 feet on the eastside of the basin. The thinning of the Kirtland and Fruitland Formations from west to east is primarily the result of erosion following tilting of the San Juan Basin area toward the west after either part or all of the upper shale member had been deposited. The overlying Ojo Alamo Sandstone rests on progressively older rocks across the basin overstepping the under lying upper shale member, Farmington Sandstone Member, Fruitland Formation, and finally resting on the Lewis Shale on the east side of the basin. The source area for the rocks of the Kirtland and Fruitland Formations was probably to the north or northwest of the San Juan Basin area. The Kirtland and Fruitland rocks have produced minor amounts of oil and gas. The Fruitland Formation contains large coal deposits some of which are currently being strip mined near Fruitland, New Mexico

Colorado, New Mexico↗

USGS2014

Geologic and geophysical maps of the eastern three-fourths of the Cambria 30' x 60' quadrangle, central California Coast Ranges

The Cambria 30´ x 60´ quadrangle comprises southwestern Monterey County and northwestern San Luis Obispo County. The land area includes rugged mountains of the Santa Lucia Range extending from the northwest to the southeast part of the map; the southern part of the Big Sur coast in the northwest; broad marine terraces along the southwest coast; and broadvalleys, rolling hills, and modest mountains in the northeast. This report contains geologic, gravity anomaly, and aeromagnetic anomaly maps of the eastern three-fourths of the 1:100,000-scale Cambria quadrangle and the associated geologic and geophysical databases (ArcMap databases), as well as complete descriptions of the geologic map units and the structural relations in the mapped area. A cross section is based on both the geologic map and potential-field geophysical data. The maps are presented as an interactive, multilayer PDF, rather than more traditional pre-formatted map-sheet PDFs. Various geologic, geophysical, paleontological, and base map elements are placed on separate layers, which allows the user to combine elements interactively to create map views beyond the traditional map sheets. Four traditional map sheets (geologic map, gravity map, aeromagnetic map, paleontological locality map) are easily compiled by choosing the associated data layers or by choosing the desired map under Bookmarks.

California↗

USGS2016

Report A: Fish and habitat assessment in Rock Creek, Klickitat County, Washington, June 2013-December 2015

The U.S. Geological Survey (USGS) and the Yakama Nation have collaborated in the Rock Creek subbasin, southeastern, Washington since 2009 to assess steelhead (Oncorynchus mykiss) populations and habitat conditions. Rock Creek, flows south to the Columbia River at river kilometer (rkm) 368. During 2015, a habitat survey was conducted, and monitoring of Passive Integrated Transponder (PIT)-tagged salmonids in the Rock Creek subbasin continued. Two multiplexing PIT-tag interrogation systems (PTISs) were installed in Rock Creek in the fall of 2009 to evaluate timing and degree of salmonid movement, smolting success, stray rates, and other life history attributes. These have been monitored every year since, during the spring, fall, and winter months. Returning adult steelhead detection histories are summarized from past Rock Creek PIT-tagging efforts. Detection histories and detection efficiencies were used to estimate a smolt-to-adult return rate (SAR) for Rock Creek PIT-tagged steelhead (tagged from 2009 to 2012) that ranged from 2.2% to 5.5%. Additionally, a SAR was also estimated for Rock Creek PIT-tagged steelhead returning to Bonneville Dam, Columbia River (rkm 235). The SAR rate to Bonneville Dam was always higher (2.4% to 10.4%), indicating straying of adults to other sites for spawning potentially further upstream or in other tributaries, or pre-spawn mortality. Twenty-two Rock Creek PIT-tagged steelhead were detected returning to Rock Creek and 35 were detected at Bonneville Dam from past tagging efforts (2009 – 2012). Monitoring of the Rock Creek PTISs [Rock Creek Lower (RCL) and Rock Creek Squaw (RCS)] provide evidence for PIT-tagged salmonid use from fish tagged outside of Rock Creek subbasin (out-of-basin) origins. A total of 82 out-of-basin PIT-tagged fish have been detected at the Rock Creek PTISs since installation. The habitat survey was conducted in Rock Creek from September 16 to October 7, 2015. The survey started at rkm 2 and continued upstream to rkm 29.3, and included portions of the major tributaries, ranging from 1 to 9 rkm survey length upstream from their confluence. During the survey, we measured the lengths of all dry and non-pool wet sections, and for pools: the length, wetted width, average residual depth, maximum residual depth, and temperature. During the 2015 survey of Rock Creek, 38% of the river between rkm 2 and 29 was classified as dry, with a higher relative proportion (57%) of dry being in the lower river section (rkm 2-13) than the upper river section (33%, rkm 14-22). This was higher than during survey years 2010 to 2012, which ranged from 29% to 43% in the lower river. As a result of the increase in dry area the percent of non-pool wet habitat was less (22%) than previous years (range 34% to 43%), as well as the percent of pools (21%). However, more river kilometers were surveyed in the lower river section (rkm 2-13) than previous years. For the 2015 survey length (rkm 2 to 29), 19% was classified as pools and 43% was non-pool wet. This work informs potential restoration actions by identifying the persistent pools across years and in years of low water flow (i.e., 2015). This work also provides a baseline to evaluate effectiveness of future restoration actions. Potential restoration actions could include headwater and upland restoration to improve base flows and pool habitat enhancement, through increased structure and vegetation plantings for increased cover. The Rock Creek steelhead population remains to be an important cultural resource for the Rock Creek Band of the Yakama Nation Tribe. The Rock Creek steelhead population is part of the Cascades Eastern Slope major population group (MPG), one of four MPGs contributing to the Middle Columbia steelhead distinct population segment (DPS). The National Marine Fisheries Service recovery plan for Rock Creek (NMFS 2009a) identifies an overall biological recovery goal for Rock Creek steelhead to contribute to recovery of the Mid-Columbia D

Washington↗

USGS2023

Biological responses of Pacific herring embryos to crude oil are quantifiable at exposure levels below conventional limits of quantitation for PAHs in water and tissues

Pacific herring ( Clupea pallasii ), a cornerstone of marine food webs, generally spawn on marine macroalgae in shallow nearshore areas that are disproportionately at risk from oil spills. Herring embryos are also highly susceptible to toxicity from chemicals leaching from oil stranded in intertidal and subtidal zones. The water-soluble components of crude oil trigger an adverse outcome pathway that involves disruption of the physiological functions of cardiomyocytes in the embryonic herring heart. In previous studies, impaired ionoregulation (calcium and potassium cycling) in response to specific polycyclic aromatic hydrocarbons (PAHs) corresponds to lethal embryolarval heart failure or subtle chamber malformations at the high and low ends of the PAH exposure range, respectively. Sublethal cardiotoxicity, which involves an abnormal outgrowth (ballooning) of the cardiac ventricular chamber soon after hatching, subsequently compromises juvenile heart structure and function, leading to pathological hypertrophy of the ventricle and reduced individual fitness, measured as cardiorespiratory performance. Previous studies have not established a threshold for these sublethal and delayed-in-time effects, even with total (∑)PAH exposures as low as 29 ng/g of wet weight (tissue dose). Here, we extend these earlier findings showing that (1) cyp1a gene expression provides an oil exposure metric that is more sensitive than typical quantitation of PAHs via GC–MS and (2) heart morphometrics in herring embryos provide a similarly sensitive measure of toxic response. Early life stage injury to herring (impaired heart development) thus occurs below the quantitation limits for PAHs in both water and embryonic tissues as a conventional basis for assessing oil-induced losses to coastal marine ecosystems.

Environmental Science and Technology↗

USGS1983

Aeromagnetic map and interpretation of geophysical data from the Condrey Mountain Roadless Area, Siskiyou County, California

The Condrey Mountain Roadless Area lies within the Klamath Mountains geologic province, a province composed of four eastward-dipping imbricate thrust slices or belts consisting predominantly of marine arc-related volcanic and sedimentary rocks, but also including significant amounts of ultramafic and other ophiolitic rocks (Irwin, 1981). From west to east the four Klamath Mountains thrust slices are called the western Jurassic belt, the western Paleozoic and Triassic belt, the central metamorphic belt, and the eastern Klamath belt. The Condrey Mountain Road less Area is located within a structural window in the western Paleozoic and Triassic belt, a window in which the structural dome comprised of the Condrey Mountain Schist is exposed (Coleman and others, 1983). North, east and south of the roadless area, the Condrey Mountain Schist is separated from the overlying western Paleozoic and Triassic belt by a low-angle regional thrust, whereas to the west the two units are in high-angle fault contact (Coleman and others, 1983). The Condrey Mountain schist consists mainly of sedimentary and volcanic rocks metamorphosed to greenschist facies. Metasedimentary rocks are exposed over most of the eastern and central parts of the structural window. Metavolcanic rocks occupy the western part of the window but also occur in small exposures within the metasedimentary rocks and along the eastern and southern margins of the window. Tabular bodies of metaserpentinite, the largest of which crops out near White Mountain, are contained within the metasedimentary rocks. Densities of hand samples from 11 sites scattered throughout the Condrey Mountain window average 2.66±0.05 g/cm 3 . The four samples of metavolcanic rocks yielded a higher average density than the seven samples of metasedimentary rocks (2.71±0.04 g/cm 3 versus 2.63±0.03 g/cm 3 ). Along the western edge of the Condrey Mountain Road less Area, numerous narrow north-trending zones of mineralized schist extend from near Copper Butte on the south, northward to Elliot Creek (Coleman and others, 1983). These zones contain abundant pyrite mineralization associated with pyrrhotite, chalcopyrite, qalena, and sphalerite. The Blue Ledge mine area, 2 mi north-northeast of Copper Butte, is located in a zone of mineralized schist. The western Paleozoic and Triassic belt that nearly surrounds the Condrey Mountain Schist is a melange of sedimentary, volcanic, and ultramafic rocks metamorphosed to amphibolite facies (Coleman and others, 1983). Only two samples of the metamorphic melange were collected near the Condrcy Mountain Road less Area, but extensive sampling of this unit southwest of the roadless area yielded an average sample density of 2.86±0.15 g/cm 3 (112 samples) (Jachens and others, 1983).

California↗

USGS2011

Sea-Floor geology and character of Eastern Rhode Island Sound West of Gay Head, Massachusetts

Gridded multibeam bathymetry covers approximately 102 square kilometers of sea floor in eastern Rhode Island Sound west of Gay Head, Massachusetts. Although originally collected for charting purposes during National Oceanic and Atmospheric Administration hydrographic survey H11922, these acoustic data and the sea-floor stations subsequently occupied to verify them (1) show the composition and terrain of the seabed, (2) provide information on sediment transport and benthic habitat, and (3) are part of an expanding series of studies that provide a fundamental framework for research and management activities (for example, windfarms and fisheries) along the Massachusetts inner continental shelf. Most of the sea floor in the study area has an undulating to faintly rippled appearance and is composed of bioturbated muddy sand, reflecting processes associated with sediment sorting and reworking. Shallower areas are composed of rippled sand and, where small fields of megaripples are present, indicate sedimentary environments characterized by processes associated with coarse bedload transport. Boulders and gravel were found on the floors of scour depressions and on top of an isolated bathymetric high where erosion has removed the Holocene marine sediments and exposed the underlying relict lag deposits of Pleistocene drift. The numerous scour depressions, which formed during storm-driven events, result in the juxtaposition of sea-floor areas with contrasting sedimentary environments and distinct gravel, sand, and muddy sand textures. This textural heterogeneity in turn creates a complex patchwork of habitats. Our observations of local variations in community structure suggest that this small-scale textural heterogeneity adds dramatically to the sound-wide benthic biological diversity.

Eastern Rhode Island Sound;West Of Gay Head;Massac↗

USGS1959

The petroleum potential of the emerged and submerged Atlantic coastal plain of the United States

Increasing geological and geophysical information about the Atlantic continental shelf of the United States is changing the basis for judging the area's petroleum potential. No nation can afford to overlook an area that overlies 175,000 cubic miles (730,000 km 3 ) of possibly petroliferous sediments (including the emerged coastal plain), though the first barrel of oil is yet to be produced. Seismic and magnetic surveys indicate that the basement is deeper and more irregular than previously supposed and that a basement ridge may separate the shelf sediments into two major elongate basins parallel to the shelf edge, thus forming possible entrapping structures and possibly restricted depositional basins. Lower Paleozoic clastic rocks found in the subsurface of Georgia and Florida, and which may occur elsewhere in downfaulted basins, could be source beds and reservoir rocks for oil and gas over wide areas. Lower Cretaceous, Upper Jurassic( ?), and Triassic sedimentary rocks recognized in some wells must wedge out updip, and numerous unconformities probably occur. The marine sediments were presumably deposited in or close to shelf areas that possibly contain reefs and are partially bordered by known granite washes; thus both source and reservoir rocks are probably present. It can be expected that petroleum will eventually be discovered beneath the continental shelf and perhaps the emerged coastal plain, but it will not be discovered (economic factors aside) until geologists have projected paleogeographic settings into the sediments beneath the shelf from the data obtained through onshore and submarine geology, drilling, and geophysics.

Conference Paper↗

USGS2006

Wave data processing toolbox manual

Researchers routinely deploy oceanographic equipment in estuaries, coastal nearshore environments, and shelf settings. These deployments usually include tripod-mounted instruments to measure a suite of physical parameters such as currents, waves, and pressure. Instruments such as the RD Instruments Acoustic Doppler Current Profiler (ADCP(tm)), the Sontek Argonaut, and the Nortek Aquadopp(tm) Profiler (AP) can measure these parameters. The data from these instruments must be processed using proprietary software unique to each instrument to convert measurements to real physical values. These processed files are then available for dissemination and scientific evaluation. For example, the proprietary processing program used to process data from the RD Instruments ADCP for wave information is called WavesMon. Depending on the length of the deployment, WavesMon will typically produce thousands of processed data files. These files are difficult to archive and further analysis of the data becomes cumbersome. More imperative is that these files alone do not include sufficient information pertinent to that deployment (metadata), which could hinder future scientific interpretation. This open-file report describes a toolbox developed to compile, archive, and disseminate the processed wave measurement data from an RD Instruments ADCP, a Sontek Argonaut, or a Nortek AP. This toolbox will be referred to as the Wave Data Processing Toolbox. The Wave Data Processing Toolbox congregates the processed files output from the proprietary software into two NetCDF files: one file contains the statistics of the burst data and the other file contains the raw burst data (additional details described below). One important advantage of this toolbox is that it converts the data into NetCDF format. Data in NetCDF format is easy to disseminate, is portable to any computer platform, and is viewable with public-domain freely-available software. Another important advantage is that a metadata structure is embedded with the data to document pertinent information regarding the deployment and the parameters used to process the data. Using this format ensures that the relevant information about how the data was collected and converted to physical units is maintained with the actual data. EPIC-standard variable names have been utilized where appropriate. These standards, developed by the NOAA Pacific Marine Environmental Laboratory (PMEL) (http://www.pmel.noaa.gov/epic/), provide a universal vernacular allowing researchers to share data without translation.

Open-File Report↗

USGS1979

Late Precambrian Sixtymile Formation and orogeny at top of the Grand Canyon Supergroup, northern Arizona

The Sixtymile Formation, a 60-m-thick red-bed unit at the top of the late Precambrian Chuar Group, crops out at three places in the Chuar syncline in the eastern Grand Canyon. Its base is marked by a transition from gray marine shale to red sandstone. The Sixtymile was deposited in the deepening trough of the north-trending Chuar syncline during and as a consequence of regional uplift, tilting, and large-scale block faulting. Folding to form the Chuar syncline occurred in response to faulting on the parallel-trending Butte fault, about 1 km to the east. About 3.2 km of structural relief was developed across the Butte fault, principally during deposition of the lower member of the Sixtymile Formation. Landslide debris shed from the upthrown block on the east constitutes a major part of the material in the lower member. Conglomeratic strata of the upper member of the Sixtymile were deposited after the last increment of subsidence on the Chuar syncline, indicating that deposition of the Sixty mile Formation spanned the time of the structural disturbance. The folding and faulting are part of a regional structural episode that here is called the Grand Canyon orogeny, an event that signaled the end of deposition of strata of the Grand Canyon Supergroup and the beginning of a long interval of erosion. The age of the Grand Canyon orogeny is estimated at about 830 m.y., inferred from an evaluation of maximum and minimum reset K-Ar ages reported for the 1,100-m.y.-old Cardenas Lavas of the Unkar Group. In age and structural style, the Grand Canyon orogeny appears generally correlative with the East Kootenay orogeny of British Columbia, which separates the Purcell (Belt) and Windermere Supergroups. By analogy, strata of the Chuar Group below the Sixtymile Formation are correlated with strata of the upper part of the Belt Supergroup, and conglomeratic strata of the Sixtymile deposited after the structural episode are correlated with conglomeratic strata of the Windermere that unconformably overlie the Belt.

Professional Paper↗

USGS2020

Green turtle mitochondrial microsatellites indicate finer-scale natal homing to isolated islands than to continental nesting sites

In highly mobile philopatric species, defining the scale of natal homing is fundamental to characterizing population dynamics and effectively managing distinct populations. Genetic tools have provided evidence of regional natal philopatry in marine turtles, but extensive sharing of maternally inherited mitochondrial control region (CR) haplotypes within regions (<500 km) often impedes identification of population boundaries. Previous CR-based analyses of Florida (USA) green turtle Chelonia mydas nesting sites detected at least 2 populations, but the ubiquity of haplotype CM-A3.1 among southern rookeries decreased the power to detect differentiation. We reassessed population structure by sequencing the mitochondrial microsatellite (short tandem repeat, mtSTR) in 786 samples from 11 nesting sites spanning 700 km from Canaveral National Seashore through Dry Tortugas National Park. The mtSTR marker subdivided CM-A3.1 into 12 haplotypes that were structured among rookeries, demonstrating independent female recruitment into the Dry Tortugas and Marquesas Keys nesting populations. Combined haplotypes provided support for recognition of at least 4 management units in Florida: (1) central eastern Florida, (2) southeastern Florida, (3) Key West National Wildlife Refuge, and (4) Dry Tortugas National Park. Recapture data indicated female nesting dispersal between islands <15 km apart, but haplotype frequencies demonstrated discrete natal homing to island groups separated by 70 km. These isolated insular rookeries may be more vulnerable to climate change-mediated nesting habitat instability than those along continental coasts and should be monitored more consistently to characterize population status. Broader application of the mtSTR markers holds great promise in improving resolution of stock structure and migratory connectivity for green turtles globally.

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