Two phases (pink and white granite) of the Sebago batholith of southwestern Maine have been dated by the U-Pb zircon method. Identical upper concordia intercepts of both rocks indicate an intrusive age of 325 ± 3 m.y. for the batholith. The lower intercept of the pink-phase sample, 114 ± 13 m.y., is inferred to represent episodic lead loss due to the intrusion of the nearby Cretaceous Pleasant Mountain stock. The lower intercept of the white-phase sample, 18 ± 21 m.y., suggests only modern dilatancy lead loss. Monazites have ages of 272 m.y. (pink) and 282 m.y. (white) which are thought to be cooling ages. Rb-Sr whole-rock data have low initial 87Sr/86Sr ratios of 0.7031 (pink) and 0.7053 (white). These data, in conjunction with published 40Ar/39Ar, Rb-Sr, K-Ar, and fission-track ages, suggest that little or no uplift occurred in this part of New England until the Permian and that the uplift rate from 275 m.y. to 225 m.y. was ∼3 times as rapid as was the rate for 225 m.y. to the present. The Carboniferous age of the Sebago batholith suggests that currently accepted metamorphic and tectonic interpretations for southwestern Maine and for east-central New Hampshire require revision.
Errors in complex conceptual precipitation-runoff models may be analyzed by placing them into a statistical framework. This amounts to treating the errors as random variables and defining the probabilistic structure of the errors. By using such a framework, a large array of techniques, many of which have been presented in the statistical literature, becomes available to the modeler for quantifying and analyzing the various sources of error. A number of these techniques are reviewed in this paper, with special attention to the peculiarities of hydrologic models. Known methodologies for parameter estimation (calibration) are particularly applicable for obtaining physically meaningful estimates and for explaining how bias in runoff prediction caused by model error and input error may contribute to bias in parameter estimation.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/WR021i008p01195","usgsCitation":"Troutman, B.M., 1985, Errors and parameter estimation in precipitation-runoff modeling: 1. Theory: Water Resources Research, v. 21, no. 8, p. 1195-1213, https://doi.org/10.1029/WR021i008p01195.","productDescription":"19 p.","startPage":"1195","endPage":"1213","costCenters":[{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":222047,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"21","issue":"8","noUsgsAuthors":false,"publicationDate":"2008-01-08","publicationStatus":"PW","scienceBaseUri":"505a0a49e4b0c8380cd522b2","contributors":{"authors":[{"text":"Troutman, Brent M.","contributorId":195329,"corporation":false,"usgs":false,"family":"Troutman","given":"Brent","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":364945,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70012954,"text":"70012954 - 1985 - Late Holocene vegetation changes in Greenwater Valley, Mojave Desert, California","interactions":[],"lastModifiedDate":"2013-01-26T15:36:31","indexId":"70012954","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3218,"text":"Quaternary Research","active":true,"publicationSubtype":{"id":10}},"title":"Late Holocene vegetation changes in Greenwater Valley, Mojave Desert, California","docAbstract":"Small-scale late Holocene vegetation changes were determined from a series of 13 modern and fossil packrat middens collected from a site in the Greenwater Valley, northern Mojave Desert, California. Although the site is above the modern lower limit of Coleogyne ramosissima (black-brush), macrofossils of this shrub are only present in samples younger than 270 yr B.P. In order to measure changes more subtle than presence vs absence, macrofossil concentrations were quantified, and principal components and factor analyses were used to distinguish midden plant assemblages. Both the presence/absence data and the statistical analyses suggest a downward shift of 50 to 100 m for Coleogyne (blackbrush) communities between 1435 and 1795 A.D. ?? 1985.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Quaternary Research","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier","publisherLocation":"Amsterdam, Netherlands","doi":"10.1016/0033-5894(85)90030-4","issn":"00335894","usgsCitation":"Cole, K., and Webb, R.H., 1985, Late Holocene vegetation changes in Greenwater Valley, Mojave Desert, California: Quaternary Research, v. 23, no. 2, p. 227-235, https://doi.org/10.1016/0033-5894(85)90030-4.","startPage":"227","endPage":"235","numberOfPages":"9","costCenters":[],"links":[{"id":266546,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0033-5894(85)90030-4"},{"id":221922,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"23","issue":"2","noUsgsAuthors":false,"publicationDate":"2017-01-20","publicationStatus":"PW","scienceBaseUri":"505a44ece4b0c8380cd66ed3","contributors":{"authors":[{"text":"Cole, K.L.","contributorId":87507,"corporation":false,"usgs":true,"family":"Cole","given":"K.L.","email":"","affiliations":[],"preferred":false,"id":364925,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Webb, R. H.","contributorId":13648,"corporation":false,"usgs":true,"family":"Webb","given":"R.","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":364924,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70012941,"text":"70012941 - 1985 - Carboniferous paleogeographic, phytogeographic, and paleoclimatic reconstructions","interactions":[],"lastModifiedDate":"2024-02-24T01:18:57.943376","indexId":"70012941","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2033,"text":"International Journal of Coal Geology","active":true,"publicationSubtype":{"id":10}},"title":"Carboniferous paleogeographic, phytogeographic, and paleoclimatic reconstructions","docAbstract":"Two revised paleogeographic reconstructions of the Visean and Westphalian C-D stages are presented based on recent paleomagnetic, phytogeographic, stratigraphic, and tectonic data. These data change the positions of some continental blocks, and allow the definition of several new ones. The most important modifications that have been incorporated in these reconstructions are: (1) a proposed isthmus linking North America and Siberia across the Bering Strait; and (2) the separation of China and Southeast Asia in six major blocks, including South China, North China, Shan Thai-Malaya, Indochina, Qangtang, and Tarim blocks. Evidence is presented that suggests that at least the South China, Shan Thai-Malaya, and Qangtang blocks were derived from the northern margin of Gondwana.
Multivariate statistical analysis of phytogeographic data from the middle and late Paleozoic allow definition of a number of different phytogeographic units for four time intervals: (1) the Early Devonian, (2) Tournaisian—early Visean, (3) Visean, and (4) late Visean—early Namurian A. Pre-late Visean—early Namurian A floral assemblages from South China show affinities with northern Gondwana floras suggesting a southerly position and provides additional support for our reconstruction of South China against the northern margin of Gondwana. There is a marked decrease in the diversity of phytogeographic units in the Namurian and younger Carboniferous. This correlates closely with the time of assembly of most of Pangaea. The general pattern of Carboniferous phytogeographic units corresponds well with global distribution of continents shown on our paleogeographic reconstructions.
In addition, we have constructed paleoclimatic maps for the two Carboniferous time intervals. These maps stress the distribution of rainfall, as this should be strongly correlated with the floras. There is marked change in the rainfall patterns between the Visean and Westphalian C-D. This change corresponds with the closing of the Appalachian-Ouachita ocean between Laurussia and Gondwana, and reflects the removal of a low-latitude moisture source that probably gave rise to monsoonal conditions along the northern margin of Gondwana in the Visean and earlier times. As well, the presence of a substantial heat source at high elevation in the Late Carboniferous significantly influenced the distribution of climatic belts.
A model for the optimal allocation of water resources was developed for a multiaquifer groundwater and surface water system near Livermore, California. The complex groundwater system was analyzed using a transient, quasi-three-dimensional model that considers the nonlinear behavior of the unconfined aquifer. The surface water system consists of a reservoir that discharges water to three streams which in turn recharge the upper aquifer. Nonlinear streamflow-recharge relationships were developed based upon synoptic field measurements of streamflow. The management model uses constrained optimization to minimize the cost of allocating surface water subject to physical and economic restrictions. Results indicate that a combined hydrologic and economic management model can be used to evaluate management practices of a complex hydrogeologic system. Questions can be posed which either would be impossible or extremely difficult to solve without the management model. We demonstrate the utility of such a model in three areas. First, the efficiency of intra-basin water allocations is evaluated. Second, critical factors that control management decisions of the basin are identified. Third, the influence of economic incentives that can best satisfy the conflicting objectives of various water users is explored.
","language":"English","publisher":"American Geophysical Union","doi":"10.1029/WR021i011p01731","usgsCitation":"Danskin, W.R., and Gorelick, S.M., 1985, A policy evaluation tool: Management of a multiaquifer system using controlled stream recharge: Water Resources Research, v. 21, no. 11, p. 1731-1747, https://doi.org/10.1029/WR021i011p01731.","productDescription":"17 p.","startPage":"1731","endPage":"1747","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":484149,"rank":3,"type":{"id":40,"text":"Open Access Publisher Index Page"},"url":"https://doi.org/10.1029/WR021i011p01731","description":"Danskin, W.R. and Gorelick, S.M., 1985, A policy evaluation tool-Management of a multi-aquifer system using controlled stream recharge: Water Resources Research, v. 21, no. 11, p. 1731–1747."},{"id":484148,"rank":2,"type":{"id":42,"text":"Open Access USGS Document"},"url":"https://pubs.usgs.gov/ja/70012936/WaterResources_Vol21_No11_p1731-1747_Nov1985_USGSOpenAccess.pdf","size":"2 MB","linkFileType":{"id":1,"text":"pdf"}},{"id":222625,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"21","issue":"11","publishedDate":"1985-11-01","noUsgsAuthors":false,"publicationDate":"1985-11-01","publicationStatus":"PW","scienceBaseUri":"5059e4dee4b0c8380cd469b3","contributors":{"authors":[{"text":"Danskin, Wesley R. 0000-0001-8672-5501 wdanskin@usgs.gov","orcid":"https://orcid.org/0000-0001-8672-5501","contributorId":1034,"corporation":false,"usgs":true,"family":"Danskin","given":"Wesley","email":"wdanskin@usgs.gov","middleInitial":"R.","affiliations":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"preferred":true,"id":364882,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Gorelick, Steven M.","contributorId":8784,"corporation":false,"usgs":true,"family":"Gorelick","given":"Steven","email":"","middleInitial":"M.","affiliations":[],"preferred":false,"id":364881,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70012929,"text":"70012929 - 1985 - Petrogenesis of the magmatic complex at Mount Ascutney, Vermont, USA - I. Assimilation of crust by mafic magmas based on Sr and O isotopic and major element relationships","interactions":[],"lastModifiedDate":"2012-03-12T17:19:10","indexId":"70012929","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1336,"text":"Contributions to Mineralogy and Petrology","active":true,"publicationSubtype":{"id":10}},"title":"Petrogenesis of the magmatic complex at Mount Ascutney, Vermont, USA - I. Assimilation of crust by mafic magmas based on Sr and O isotopic and major element relationships","docAbstract":"The Ascutney Mountain igneous complex in eastern Vermont, USA, is composed of three principal units with compositions ranging from gabbro to granite. Sr and O isotopic and major element relationships for mafic rocks, granites, and nearby gneissic and schistose country rock have been investigated in order to describe the petrogenesis of the mafic suite which ranges from gabbro to diorite. The entire complex appears to have been formed within a short interval 122.2??1.2 m.y. ago. The granites with ??18O near +7.8??? had an initial 87Sr/86Sr of 0.70395(??6) which is indistinguishable from the initial ratio of the most primitive gabbro. Initial 87Sr/86Sr ratios and ??18O values for the mafic rocks range from 0.7039 to 0.7057 and +6.1 to +8.6???, respectively. The isotopic ratios are highly correlated with major element trends and reflect considerable crustal contamination of a mantle-derived basaltic parent magma. The likely contaminant was Precambrian gneiss similar to exposed bedrock into which the basic rocks were emplaced. A new approach to modelling of assimilation during the formation of a cogenetic igneous rock suite is illustrated. Chemical and isotopic modelling indicate that the mafic rocks were produced by simultaneous assimilation and fractional crystallization. The relative amounts of fractionation and assimilation varied considerably. The mafic suite was not produced by a single batch of magma undergoing progressive contamination; rather, the various rocks probably were derived from separate batches of magma each of which followed a separate course of evolution. The late stage granite was apparently derived from basaltic magma by fractionation with little or no crustal assimilation. The early intrusive phases are much more highly contaminated than the final one. The observed relationships have important implications for the formation of comagmatic complexes and for isotopic modelling of crustal contamination. ?? 1985 Springer-Verlag.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Contributions to Mineralogy and Petrology","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisherLocation":"Springer-Verlag","doi":"10.1007/BF00384712","issn":"00107999","usgsCitation":"Foland, K., Henderson, C., and Gleason, J., 1985, Petrogenesis of the magmatic complex at Mount Ascutney, Vermont, USA - I. Assimilation of crust by mafic magmas based on Sr and O isotopic and major element relationships: Contributions to Mineralogy and Petrology, v. 90, no. 4, p. 331-345, https://doi.org/10.1007/BF00384712.","startPage":"331","endPage":"345","numberOfPages":"15","costCenters":[],"links":[{"id":205251,"rank":9999,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1007/BF00384712"},{"id":222509,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"90","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505a7784e4b0c8380cd784ff","contributors":{"authors":[{"text":"Foland, K.A.","contributorId":13357,"corporation":false,"usgs":true,"family":"Foland","given":"K.A.","email":"","affiliations":[],"preferred":false,"id":364863,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Henderson, C.M.B.","contributorId":41970,"corporation":false,"usgs":true,"family":"Henderson","given":"C.M.B.","email":"","affiliations":[],"preferred":false,"id":364865,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Gleason, J.","contributorId":16975,"corporation":false,"usgs":true,"family":"Gleason","given":"J.","affiliations":[],"preferred":false,"id":364864,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70012921,"text":"70012921 - 1985 - A two-dimensional dam-break flood plain model","interactions":[],"lastModifiedDate":"2023-02-01T17:33:30.595254","indexId":"70012921","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":664,"text":"Advances in Water Resources","active":true,"publicationSubtype":{"id":10}},"title":"A two-dimensional dam-break flood plain model","docAbstract":"A simple two-dimensional dam-break model is developed for flood plain study purposes. Both a finite difference grid and an irregular triangle element integrated finite difference formulation are presented. The governing flow equations are approximately solved as a diffusion model coupled to the equation of continuity. Application of the model to a hypothetical dam-break study indicates that the approach can be used to predict a two-dimensional dam-break flood plain over a broad, flat plain more accurately than a one-dimensional model, especially when the flow can break-out of the main channel and then return to the channel at other downstream reaches. ?? 1985.","language":"English","publisher":"Elsevier","doi":"10.1016/0309-1708(85)90074-0","usgsCitation":"Hromadka, T., Berenbrock, C., Freckleton, J.R., and Guymon, G.L., 1985, A two-dimensional dam-break flood plain model: Advances in Water Resources, v. 8, no. 1, p. 7-14, https://doi.org/10.1016/0309-1708(85)90074-0.","productDescription":"8 p.","startPage":"7","endPage":"14","numberOfPages":"8","costCenters":[{"id":154,"text":"California Water Science Center","active":true,"usgs":true}],"links":[{"id":222387,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"8","issue":"1","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5059e608e4b0c8380cd470fb","contributors":{"authors":[{"text":"Hromadka, T. V. II","contributorId":76464,"corporation":false,"usgs":true,"family":"Hromadka","given":"T. V.","suffix":"II","affiliations":[],"preferred":false,"id":364842,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Berenbrock, C. E.","contributorId":103321,"corporation":false,"usgs":true,"family":"Berenbrock","given":"C. E.","affiliations":[],"preferred":false,"id":364845,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Freckleton, J. R.","contributorId":93498,"corporation":false,"usgs":true,"family":"Freckleton","given":"J.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":364844,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Guymon, G. L.","contributorId":83941,"corporation":false,"usgs":true,"family":"Guymon","given":"G.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":364843,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70012920,"text":"70012920 - 1985 - Degradation of carbohydrates and lignins in buried woods","interactions":[],"lastModifiedDate":"2024-03-19T16:50:06.752297","indexId":"70012920","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1759,"text":"Geochimica et Cosmochimica Acta","active":true,"publicationSubtype":{"id":10}},"title":"Degradation of carbohydrates and lignins in buried woods","docAbstract":"Spruce, alder, and oak woods deposited in coastal sediments were characterized versus their modern counterparts by quantification of individual neutral sugars and lignin-derived phenols as well as by scanning electron microscopy, 13C NMR, and elemental analysis. The buried spruce wood from a 2500 yr old deposit was unaltered whereas an alder wood from the same horizon and an oak wood from an open ocean sediment were profoundly degraded. Individual sugar and lignin phenol analyses indicate that at least 90 and 98 wt% of the initial total polysaccharides in the buried alder and oak woods, respectively, have been degraded along with 15–25 wt% of the lignin. At least 75% of the degraded biopolymer has been physically lost from these samples. This evidence is supported by the SEM, 13C NMR and elemental analyses, all of which indicate selective loss of the carbohydrate moiety. The following order of stability was observed for the major biochemical constituents of both buried hardwoods: vanillyl and
In this review of developments in the field of remote sensing from a geophysical perspective, the subject is limited to the electromagnetic spectrum from 0.4 mu m to 25 cm. Three broad energy categories are covered: solar reflected, thermal infrared, and microwave.The reflected solar region has been the most intensely studied. Photointerpretation of images from individual spectral bands or from color composites remains the most widely used method of analysis. New instrumentation and digital processing, based on analysis of laboratory and field spectra, provide significant advances that are beginning to be applied to resource exploration. Color compositing techniques have been effectively used to detect the characteristic spectral reflectance features of iron oxides and hydroxyl-bearing materials in satellite multispectral data for mapping areas of hydrothermal alteration. Airborne spectrometers can now detect individual spectral features of many minerals which are diagnostic of different stages of hydrothermal alteration. Evolution was from discrimination, based on empirical experience, to mineralogic identification and leading to quantification. Current developments also indicate new, promising extensions to vegetated terrains.Advances in thermal infrared studies are due to development of thermal models that permit mapping of physical property variations and to detection of spectral differences that provide important compositional information. Analysis techniques are still in their infancy, and thermal satellite data remain appropriate only for regional investigations.Microwave data have been acquired mainly with radar systems, which can provide very high resolution from space, but use of textural and slope information has had limited application. Long-wavelength radiation has been shown to penetrate dry materials, and this may be applicable in extremely arid regions.
","language":"English","publisher":"Society of Exploration Geophysicists","doi":"10.1190/1.1441885","issn":"00168033","usgsCitation":"Watson, K., 1985, Remote sensing; a geophysical perspective: Geophysics, v. 50, no. 12, p. 2595-2610, https://doi.org/10.1190/1.1441885.","productDescription":"16 p.","startPage":"2595","endPage":"2610","numberOfPages":"16","costCenters":[],"links":[{"id":222332,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"50","issue":"12","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"505aa713e4b0c8380cd851eb","contributors":{"authors":[{"text":"Watson, K.","contributorId":39123,"corporation":false,"usgs":true,"family":"Watson","given":"K.","email":"","affiliations":[],"preferred":false,"id":364830,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":1001851,"text":"1001851 - 1985 - Improving waterfowl production estimates: Results of a test in the prairie pothole region","interactions":[],"lastModifiedDate":"2017-08-31T11:07:57","indexId":"1001851","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2019,"text":"International Congress of Game Biologists","active":true,"publicationSubtype":{"id":10}},"title":"Improving waterfowl production estimates: Results of a test in the prairie pothole region","docAbstract":"The U.S. Fish and Wildlife Service in an effort to improve and standardize methods for estimating waterfowl production tested a new technique in the four-county Arrowwood Wetland Management District (WMD) for three years (1982-1984). On 14 randomly selected 10.36 km2 plots, upland and wetland habitat was mapped, classified, and digitized. Waterfowl breeding pairs were counted twice each year and the proportion of wetland basins containing water was determined. Pair numbers and habitat conditions were entered into a computer model developed by Northern Prairie Wildlife Research Center. That model estimates production on small federally owned wildlife tracts, federal wetland easements, and private land. Results indicate that production estimates were most accurate for mallards (Anas platyrhynchos), the species for which the computer model and data base were originally designed. Predictions for the pintail (Anas acuta), gadwall (A. strepa), blue-winged teal (A. discors), and northern shoveler (A. clypeata) were believed to be less accurate. Modeling breeding period dynamics of a waterfowl species and making credible production estimates for a geographic area are possible if the data used in the model are adequate. The process of modeling the breeding period of a species aids in locating areas of insufficient biological knowledge. This process will help direct future research efforts and permit more efficient gathering of field data.","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"International Congress of Game Biologists","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","usgsCitation":"Arnold, P., and Cowardin, L., 1985, Improving waterfowl production estimates: Results of a test in the prairie pothole region: International Congress of Game Biologists, v. 17, p. 859-865.","productDescription":"7 p.","startPage":"859","endPage":"865","costCenters":[{"id":480,"text":"Northern Prairie Wildlife Research Center","active":true,"usgs":true}],"links":[{"id":134425,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"17","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e49fce4b07f02db5f5a18","contributors":{"authors":[{"text":"Arnold, P.M.","contributorId":63750,"corporation":false,"usgs":true,"family":"Arnold","given":"P.M.","email":"","affiliations":[],"preferred":false,"id":311934,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Cowardin, L.M.","contributorId":106435,"corporation":false,"usgs":true,"family":"Cowardin","given":"L.M.","email":"","affiliations":[],"preferred":false,"id":311935,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":1001412,"text":"1001412 - 1985 - Mallard recruitment in the agricultural environment of North Dakota","interactions":[],"lastModifiedDate":"2017-09-14T10:33:22","indexId":"1001412","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3773,"text":"Wildlife Monographs","active":true,"publicationSubtype":{"id":10}},"title":"Mallard recruitment in the agricultural environment of North Dakota","docAbstract":"Recruitment of a mallard (Anas platyrhynchos) population was assessed on a 10,041-km2 study area in central North Dakota during 1977-80. We equipped 338 hens with radio transmitters and monitored them during the breeding season. Two hundred thirty-five of these hens furnished data reported here. Habitat use, nest site selection, fate of nests, and the rate of renesting were measured. Survival of hens during April-September and survival of young were determined. There was a high negative correlation between nest initiation date and mean April or May temperature. Hens selected nest sites most frequently in grassland and least frequently in cropland, but habitat use compared to availability indicated preference for road right-of-way and odd areas of cover and rejection of cropland. Use of other habitats was in proportion to their availability. Nest success was only 8% during the study. Hen success, a function of nest success and renesting rate, averaged 15% and varied among years because of increased renesting in wet years. In all years, 2-year-old and older hens were twice as successful as first-year nesters. Nesting effort was correlated with water conditions as derived from aerial photographs. April-September survival of hens averaged 80% because predation was heavy when hens were on nests. Only 74% of the hens that hatched a clutch were observed later with at least 1 surviving duckling. On average, hens in the spring population recruited only 0.27 young females to the fall population. Based on this recruitment estimate, published survival estimates and a model previously developed for a closed population, we predict a 20% annual population decline. Nest success of 15% and a resulting hen success of 31% would be required for a stable population. The results suggest that the population on the study area is not maintaining itself but is being supplemented by pioneering birds. A serious recruitment problem has resulted from nest predation. Additional research is needed to determine the geographic extent of the problem. If the problem is widespread, management techniques must be devised to overcome nest destruction, mortality of hens, and mortality of ducklings.","language":"English","publisher":"Wildlife Society","usgsCitation":"Cowardin, L., Gilmer, D., and Shaiffer, C., 1985, Mallard recruitment in the agricultural environment of North Dakota: Wildlife Monographs, v. 92, p. 3-37.","productDescription":"36 p.","startPage":"3","endPage":"37","costCenters":[{"id":480,"text":"Northern Prairie Wildlife Research Center","active":true,"usgs":true}],"links":[{"id":133851,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -101.656494140625,\n 46.32417161725691\n ],\n [\n -99.06372070312499,\n 46.32417161725691\n ],\n [\n -99.06372070312499,\n 47.37603463349758\n ],\n [\n -101.656494140625,\n 47.37603463349758\n ],\n [\n -101.656494140625,\n 46.32417161725691\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"92","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4a81e4b07f02db64a010","contributors":{"authors":[{"text":"Cowardin, L.M.","contributorId":106435,"corporation":false,"usgs":true,"family":"Cowardin","given":"L.M.","email":"","affiliations":[],"preferred":false,"id":310995,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Gilmer, D.S.","contributorId":22270,"corporation":false,"usgs":true,"family":"Gilmer","given":"D.S.","email":"","affiliations":[],"preferred":false,"id":310993,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Shaiffer, Charles W.","contributorId":74325,"corporation":false,"usgs":true,"family":"Shaiffer","given":"Charles W.","affiliations":[],"preferred":false,"id":310994,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":1001574,"text":"1001574 - 1985 - The need for accuracy in modelling: An example","interactions":[],"lastModifiedDate":"2023-09-29T16:42:35.497251","indexId":"1001574","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1458,"text":"Ecological Modelling","active":true,"publicationSubtype":{"id":10}},"title":"The need for accuracy in modelling: An example","docAbstract":"The need for accurate information in modelling depends on the objectives of the effort, but trustworthy data are essential for a model intended for use in the management of natural resources. This point is illustrated by referring to a recently published model of canvasback ducks. We demonstrate that several key assumptions are not supported by biological evidence, and that inferences drawn from the model could be dangerously misleading if they were used to guide the management of canvasback ducks.","language":"English","publisher":"Elsevier","doi":"10.1016/0304-3800(85)90041-9","usgsCitation":"Johnson, D., Conroy, M.J., and Nichols, J.D., 1985, The need for accuracy in modelling: An example: Ecological Modelling, v. 30, no. 1-2, p. 157-161, https://doi.org/10.1016/0304-3800(85)90041-9.","productDescription":"5 p.","startPage":"157","endPage":"161","numberOfPages":"4","costCenters":[{"id":480,"text":"Northern Prairie Wildlife Research Center","active":true,"usgs":true},{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"links":[{"id":129129,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"30","issue":"1-2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b32e4b07f02db6b4721","contributors":{"authors":[{"text":"Johnson, Douglas H. 0000-0002-7778-6641","orcid":"https://orcid.org/0000-0002-7778-6641","contributorId":221269,"corporation":false,"usgs":true,"family":"Johnson","given":"Douglas H.","affiliations":[{"id":480,"text":"Northern Prairie Wildlife Research Center","active":true,"usgs":true}],"preferred":true,"id":311282,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Conroy, Michael J.","contributorId":20871,"corporation":false,"usgs":false,"family":"Conroy","given":"Michael","email":"","middleInitial":"J.","affiliations":[{"id":13266,"text":"Warnell School of Forestry and Natural Resources, The University of Georgia","active":true,"usgs":false}],"preferred":false,"id":311283,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Nichols, James D. 0000-0002-7631-2890 jnichols@usgs.gov","orcid":"https://orcid.org/0000-0002-7631-2890","contributorId":200533,"corporation":false,"usgs":true,"family":"Nichols","given":"James","email":"jnichols@usgs.gov","middleInitial":"D.","affiliations":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"preferred":true,"id":311281,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":2002136,"text":"2002136 - 1985 - A model of climatic variables affecting bighorn lamb survival in Canyonlands National Park, Utah","interactions":[],"lastModifiedDate":"2012-02-02T00:15:03","indexId":"2002136","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":1,"text":"Federal Government Series"},"seriesTitle":{"id":91,"text":"Technical Report","active":true,"publicationSubtype":{"id":1}},"seriesNumber":"CPSU/UNLV 031/02","title":"A model of climatic variables affecting bighorn lamb survival in Canyonlands National Park, Utah","docAbstract":"No abstract available at this time","language":"English","publisher":"National Park Service","usgsCitation":"Douglas, C.L., and Annable, C., 1985, A model of climatic variables affecting bighorn lamb survival in Canyonlands National Park, Utah: Technical Report CPSU/UNLV 031/02, 18 p.","productDescription":"18 p.","startPage":"0","endPage":"18","numberOfPages":"18","costCenters":[{"id":651,"text":"Western Ecological Research Center","active":true,"usgs":true}],"links":[{"id":198225,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b23e4b07f02db6adf50","contributors":{"authors":[{"text":"Douglas, C. L.","contributorId":64586,"corporation":false,"usgs":true,"family":"Douglas","given":"C.","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":326041,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Annable, C.","contributorId":24053,"corporation":false,"usgs":true,"family":"Annable","given":"C.","email":"","affiliations":[],"preferred":false,"id":326040,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":1013696,"text":"1013696 - 1985 - Detection of Vibrio anguillarum antigen by the dot blot assay","interactions":[],"lastModifiedDate":"2024-07-19T10:56:32.836553","indexId":"1013696","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2507,"text":"Journal of Wildlife Diseases","active":true,"publicationSubtype":{"id":10}},"title":"Detection of Vibrio anguillarum antigen by the dot blot assay","docAbstract":"The dot blot assay, modified and adapted for detection of antigens from Vibrio anguillarum in fish tissues, was specific for V. anguillarum and did not react with antigens of V. ordalii, Pseudomonas sp., or Yersinia ruckeri. The blot assay enabled detection of as little as 2.3 ng of a mixture of protein antigens obtained from cell-free extracts of V. anguillarum; it was about 100 times more sensitive than either the indirect fluorescent antibody technique or bacterial isolation for detecting V. anguillarum in fish tissues.
The survival and growth rates of rainbow trout (Salmo gairdnieri) were concurrently measured with selected limnological characteristics in nine small (surface area < 25 sq hectometers) lakes in the Matanuska-Susitna Borough. The project goal was to develop empirical models for predicting rainbow trout growth rates from the following variables: total phosphorus concentration, chlorophyll a concentration, Secchi disc transparency, or the morphoedaphic index--a means of characterizing potential biological productivity. No suitable model could be developed from the data collected during 1982 and 1983. The lack of significant correlation was attributed in part to the wide variation in survival of rainbow trout. Winterkills, caused by severe depletion of dissolved oxygen, were suspected in four of the lakes. Varied levels of fishing pressure and competition with threespine stickleback (Gasterosteus aculeatus) also influenced survival of rainbow trout but their effects were overshadowed by winterkill. Predictive capability was also reduced because of inconsistencies in rankings generated by each of the four limnological variables chosen as indicators of potential biological productivity. A lake ranked low in productivity by one variable was commonly ranked high in productivity by another variable. The survivability of rainbow trout stocked in lakes such as these nine may be a more important indicator of potential biomass production than are indicators of lake fertility. Assessments of a lake 's susceptibility to winterkill and the degree of competition with threespine stickleback are suggested as important topics for additional research.
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/wri854292","usgsCitation":"Woods, P.F., 1985, Limnology of nine small lakes, Matanuska-Susitna Borough, Alaska, and the survival and growth rates of rainbow trout: U.S. Geological Survey Water-Resources Investigations Report 85-4292, iv, 32 p., https://doi.org/10.3133/wri854292.","productDescription":"iv, 32 p.","costCenters":[],"links":[{"id":414141,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_36430.htm","linkFileType":{"id":5,"text":"html"}},{"id":59341,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1985/4292/report.pdf","linkFileType":{"id":1,"text":"pdf"}},{"id":123988,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1985/4292/report-thumb.jpg"}],"country":"United States","state":"Alaska","otherGeospatial":"Matanuska-Susitna Borough, Alaska","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -149.817,\n 61.833\n ],\n [\n -149.817,\n 61.45\n ],\n [\n -148.267,\n 61.45\n ],\n [\n -148.267,\n 61.833\n ],\n [\n -149.817,\n 61.833\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4b15e4b07f02db6a50f9","contributors":{"authors":[{"text":"Woods, P. F.","contributorId":97509,"corporation":false,"usgs":true,"family":"Woods","given":"P.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":203490,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":29912,"text":"wri854087 - 1985 - Ground-water flow in the Prairie du Chien-Jordan aquifer related to contamination by coal-tar derivatives, St. Louis Park, Minnesota","interactions":[],"lastModifiedDate":"2023-03-13T19:17:59.193897","indexId":"wri854087","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":342,"text":"Water-Resources Investigations Report","code":"WRI","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"85-4087","title":"Ground-water flow in the Prairie du Chien-Jordan aquifer related to contamination by coal-tar derivatives, St. Louis Park, Minnesota","docAbstract":"A three-dimensional, ground-water-flow model of the Prairie du Chien-Jordan aquifer and associated hydrogeologic units was developed to evaluate the movement of coal-tar derivatives from a coal-tar distillation and wood-preserving plant in St. Louis Park, Minnesota. A finite-difference grid was superimposed on the modeled area, which includes most of eastern Hennepin County. The individual cells are 400-foot squares in the center of the grid (St. Louis Park area); the cells increase in dimension toward the outside limits of the grid. Five geologic units are represented by four layers in the model. These units include the Jordan Sandstone, the Prairie du Chien Group (dolomite and sandy dolomite), the basal confining unit of the St. Peter Sandstone (silty and sandy shale), the St. Peter Sandstone, and glacial deposits in bedrock valleys.
The model was calibrated for steady-state conditions for a period before significant ground-water development (1885-1930) and for a period of significant pumping stress (winter conditions, 1970 fs). A transient calibration was accomplished by simulation of a period during which seasonal changes in potentiometric head in the Prairie du Chien-Jordan aquifer were significant (1977-80). Sensitivity testing indicated that leakage to the upper model layer and the vertical hydraulic conductivity of the basal confining unit of the St. Peter Sandstone were the model hydrologic properties which, when changed, resulted in the greatest changes in model-calculated water levels. The calibrated model generally calculates water levels that are within 10 feet of measured values.
Model simulations indicate that the potentiometric surface of the Prairie du Chien-Jordan aquifer would be raised by as much as 3 feet in the area of the plant site by water introduced into the aquifer through wells open to more than one aquifer system. The cones of impression created at these wells could have a significant impact on the transport of contaminants in the Prairie du Chien-Jordan.
The presence of coal-tar derivatives in the aquifer has been difficult to explain in wells located upgradient from the plant site to the north, west, and southwest. Simulations suggest that, during periods of heavy withdrawal from certain of these wells (SLP10, SLP15, and SLP5), local hydraulic gradients may have been altered, resulting in the potential for the movement of contaminants from the area of the plant site to the wells. Cones of impression at multiaquifer wells near the plant site contributed to the alteration of local gradients.
Simulation of a proposed gradient-control plan, in which lateral homogeneity and isotropy of individual hydro geologic units was assumed, indicates that the actions would be effective in limiting expansion of the contaminated volume in the Prairie du Chien-Jordan aquifer. The plan includes the control of withdrawal from five wells. The simulations also show, however, that modelcalculated potentiometric surfaces are sensitive to changes in withdrawal rates at wells not intended to be under the control of the plan. Management of discharge from these wells also will be important to overall effectiveness of the remedial-action plan.
","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"St. Paul, MN","doi":"10.3133/wri854087","usgsCitation":"Stark, J., and Hult, M.F., 1985, Ground-water flow in the Prairie du Chien-Jordan aquifer related to contamination by coal-tar derivatives, St. Louis Park, Minnesota: U.S. Geological Survey Water-Resources Investigations Report 85-4087, v, 57 p., https://doi.org/10.3133/wri854087.","productDescription":"v, 57 p.","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":392,"text":"Minnesota Water Science Center","active":true,"usgs":true}],"links":[{"id":414036,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_36260.htm","linkFileType":{"id":5,"text":"html"}},{"id":119515,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/wri/1985/4087/report-thumb.jpg"},{"id":58730,"rank":2,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/wri/1985/4087/report.pdf","linkFileType":{"id":1,"text":"pdf"}}],"country":"United States","state":"Minnesota","city":"St. Louis Park","otherGeospatial":"Prairie du Chien-Jordan aquifer","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -93.167,\n 45.083\n ],\n [\n -93.583,\n 45.083\n ],\n [\n -93.583,\n 44.783\n ],\n [\n -93.167,\n 44.783\n ],\n [\n -93.167,\n 45.083\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"4f4e4aafe4b07f02db66cd74","contributors":{"authors":[{"text":"Stark, J. R.","contributorId":100406,"corporation":false,"usgs":true,"family":"Stark","given":"J. R.","affiliations":[],"preferred":false,"id":202343,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Hult, M. F.","contributorId":29817,"corporation":false,"usgs":true,"family":"Hult","given":"M.","email":"","middleInitial":"F.","affiliations":[],"preferred":false,"id":202342,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70197164,"text":"70197164 - 1985 - The Steens Mountain (Oregon) geomagnetic polarity transition, 2. Field intensity variations and discussion of reversal models","interactions":[],"lastModifiedDate":"2018-05-18T14:26:27","indexId":"70197164","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2314,"text":"Journal of Geophysical Research B: Solid Earth","active":true,"publicationSubtype":{"id":10}},"title":"The Steens Mountain (Oregon) geomagnetic polarity transition, 2. Field intensity variations and discussion of reversal models","docAbstract":"We carried out an extensive paleointensity study of the 15.5±0.3 m.y. Miocene reversed‐to‐normal polarity transition recorded in lava flows from Steens Mountain (south central Oregon). One hundred eighty‐five samples from the collection whose paleodirectional study is reported by Mankinen et al. (this issue) were chosen for paleointensity investigations because of their low viscosity index, high Curie point and reversibility, or near reversibility, of the strong field magnetization curve versus temperature. Application of the Thellier stepwise double heating method was very successful, yielding 157 usable paleointensity estimates corresponding to 73 distinct lava flows. After grouping successive lava flows that did not differ significantly in direction and intensity, we obtained 51 distinguishable, complete field vectors of which 10 are reversed, 28 are transitional, and 13 are normal. The record is complex, quite unlike that predicted by simple flooding or standing nondipole field models. It begins with an estimated several thousand years of reversed polarity with an average intensity of 31.5±8.5 μT, about one third lower than the expected Miocene intensity. This difference is interpreted as a long‐term reduction of the dipole moment prior to the reversal. When site directions and intensities are considered, truly transitional directions and intensities appear almost at the same time at the beginning of the transition, and they disappear simultaneously at the end of the reversal. Large deviations in declination occur during this approximately 4500±1000 year transition period that are compatible with roughly similar average magnitudes of zonal and nonzonal field components at the site. The transitional intensity is generally low, with an average of 10.9±4.9 μT for directions more than 45° away from the dipole field and a minimum of about 5 μT. The root‐mean‐square of the three field components X, Y, and Z are of the same order of magnitude for the transitional field and the historical nondipole field at the site latitude. However, a field intensity increase to pretransitional values occurs when the field temporarily reaches normal directions, which suggests that dipolar structure could have been briefly regenerated during the transition in an aborted attempt to reestablish a stationary field. Changes in the field vector are progressive but jerky, with at least two, and possibly three, large swings at astonishingly high rates. Each of those transitional geomagnetic impulses occurs when the field intensity is low (less than 10 μT) and is followed by an interval of directional stasis during which the magnitude of the field increases greatly. For the best documented geomagnetic impulse the rapid directional change corresponds to a vectorial intensity change of 6700±2700 nT yr−1, which is about 15–50 times larger than the maximum rate of change of the nondipole field observed during the last centuries. The occurrence of geomagnetic impulses seems to support reversal models assuming an increase in the level of turbulence within the liquid core during transitions. The record closes with an estimated several thousand years of normal polarity with an average intensity of 46.7±20.1 μT, agreeing with the expected Miocene value. However, the occurrence of rather large and apparently rapid intensity fluctuations accompanied by little change in direction suggests that the newly reestablished dipole was still somewhat unstable.
","language":"English","publisher":"AGU","doi":"10.1029/JB090iB12p10417","usgsCitation":"Prevot, M., Mankinen, E.A., Coe, R.S., and Gromme, C.S., 1985, The Steens Mountain (Oregon) geomagnetic polarity transition, 2. Field intensity variations and discussion of reversal models: Journal of Geophysical Research B: Solid Earth, v. 90, no. B12, p. 10417-10448, https://doi.org/10.1029/JB090iB12p10417.","productDescription":"32 p.","startPage":"10417","endPage":"10448","costCenters":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"links":[{"id":354331,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"90","issue":"B12","noUsgsAuthors":false,"publicationDate":"2012-09-20","publicationStatus":"PW","scienceBaseUri":"5aff3a76e4b0da30c1bfd9fd","contributors":{"authors":[{"text":"Prevot, M.","contributorId":75679,"corporation":false,"usgs":true,"family":"Prevot","given":"M.","email":"","affiliations":[],"preferred":false,"id":735876,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Mankinen, Edward A. 0000-0001-7496-2681 emank@usgs.gov","orcid":"https://orcid.org/0000-0001-7496-2681","contributorId":1054,"corporation":false,"usgs":true,"family":"Mankinen","given":"Edward","email":"emank@usgs.gov","middleInitial":"A.","affiliations":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"preferred":true,"id":735877,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Coe, Robert S.","contributorId":20477,"corporation":false,"usgs":true,"family":"Coe","given":"Robert","email":"","middleInitial":"S.","affiliations":[],"preferred":false,"id":735878,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Gromme, C. Sherman","contributorId":22236,"corporation":false,"usgs":true,"family":"Gromme","given":"C.","email":"","middleInitial":"Sherman","affiliations":[],"preferred":false,"id":735879,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70197496,"text":"70197496 - 1985 - Paleomagnetism and geology of Eocene volcanic rocks of southwest Washington, implications for mechanisms of tectonic rotation","interactions":[],"lastModifiedDate":"2018-06-07T15:29:48","indexId":"70197496","displayToPublicDate":"1985-01-01T00:00:00","publicationYear":"1985","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2312,"text":"Journal of Geophysical Research","active":true,"publicationSubtype":{"id":10}},"title":"Paleomagnetism and geology of Eocene volcanic rocks of southwest Washington, implications for mechanisms of tectonic rotation","docAbstract":"