Subaqueous tuff deposits within the lower Miocene Lospe Formation of the Santa Maria Basin, California, are up to 20 m thick and were deposited by high density turbidity flows after large volumes of ash were supplied to the basin and remobilized. Tuff units in the Lospe Formation include a lower lithofacies assemblage of planar bedded tuff that grades upward into massive tuff, which in turn is overlain by an upper lithofacies assemblage of alternating thin bedded, coarse grained tuff beds and tuffaceous mudstone. The planar bedded tuff ranges from 0.3 to 3 m thick and contains 1-8 cm thick beds that exhibit inverse grading, and low angle and planar laminations. The overlying massive tuff ranges from 1 to 10 m thick and includes large intraclasts of pumiceous tuff and stringers of pumice grains aligned parallel to bedding. The upper lithofacies assemblage of thin bedded tuff ranges from 0.4 to 3 m thick; individual beds are 6-30 cm thick and display planar laminae and dewatering structures. Pumice is generally concentrated in the upper halves of beds in the thin bedded tuff interval.
The association of sedimentary structures combined with semi-quantitative analysis for dispersive and hydraulic equivalence of bubble-wall vitric shards and pumice grains reveals that particles in the planar bedded lithofacies are in dispersive, not settling, equivalence. This suggests deposition under dispersive pressures in a tractive flow. Grains in the overlying massive tuff are more closely in settling equivalence as opposed to dispersive equivalence, which suggests rapid deposition from a suspended sediment load. The set of lithofacies that comprises the lower lithofacies assemblage of each of the Lospe Formation tuff units is analogous to those of traction carpets and subsequent suspension sedimentation deposits often attributed to high density turbidity flows. Grain distributions in the upper thin bedded lithofacies do not reveal a clear relation for dispersive or settling equivalence. This information, together with the association of sedimentary features in the thin bedded lithofacies, including dewatering structures, suggests a combination of tractive and liquefied flows.
Absence of evidence for elevated emplacement temperatures (e.g. eutaxitic texture or shattered crystàls) suggests emplacement of the Lospe Formation tuff deposits in a cold state closely following pyroclastic eruptions. The tuff deposits are not only a result of primary volcanic processes which supplied the detritus, but also of processes which involved remobilization of unconsolidated ash as subaqueous sediment gravity flows. These deposits provide an opportunity to study the sedimentation processes that may occur during subaqueous volcaniclastic flows and demonstrate similarities with existing models for sediment gravity flow processes.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1365-3091.1994.tb01391.x","usgsCitation":"Cole, R.B., and Stanley, R.G., 1994, Sedimentology of subaqueous volcaniclastic sediment gravity flows in the Neogene Santa Maria Basin, California: Sedimentology, v. 41, no. 1, p. 37-54, https://doi.org/10.1111/j.1365-3091.1994.tb01391.x.","productDescription":"18 p. ","startPage":"37","endPage":"54","costCenters":[],"links":[{"id":339106,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"41","issue":"1","noUsgsAuthors":false,"publicationDate":"2006-06-14","publicationStatus":"PW","scienceBaseUri":"58e35f90e4b09da67997ecf6","contributors":{"authors":[{"text":"Cole, Ronald B.","contributorId":190386,"corporation":false,"usgs":false,"family":"Cole","given":"Ronald","email":"","middleInitial":"B.","affiliations":[],"preferred":false,"id":688307,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Stanley, Richard G. 0000-0001-6192-8783 rstanley@usgs.gov","orcid":"https://orcid.org/0000-0001-6192-8783","contributorId":1832,"corporation":false,"usgs":true,"family":"Stanley","given":"Richard","email":"rstanley@usgs.gov","middleInitial":"G.","affiliations":[{"id":312,"text":"Geology, Minerals, Energy, and Geophysics Science Center","active":true,"usgs":true}],"preferred":true,"id":688308,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70186257,"text":"70186257 - 1994 - Regional propagation characteristics and source parameters of earthquakes in northeastern North America","interactions":[],"lastModifiedDate":"2023-10-24T11:32:04.13597","indexId":"70186257","displayToPublicDate":"1994-02-01T00:00:00","publicationYear":"1994","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1135,"text":"Bulletin of the Seismological Society of America","onlineIssn":"1943-3573","printIssn":"0037-1106","active":true,"publicationSubtype":{"id":10}},"title":"Regional propagation characteristics and source parameters of earthquakes in northeastern North America","docAbstract":"The vertical components of the S wave trains recorded on the Eastern Canadian Telemetered Network (ECTN) from 1980 through 1990 have been spectrally analyzed for source, site, and propagation characteristics. The data set comprises some 1033 recordings of 97 earthquakes whose magnitudes range from M ≈ 3 to 6. The epicentral distances range from 15 to 1000 km, with most of the data set recorded at distances from 200 to 800 km. The recorded S wave trains contain the phases S, SmS, Sn, and Lg and are sampled using windows that increase with distance; the acceleration spectra were analyzed from 1.0 to 10 Hz. To separate the source, site, and propagation characteristics, an inversion for the earthquake corner frequencies, low-frequency levels, and average attenuation parameters is alternated with a regression of residuals onto the set of stations and a grid of 14 distances ranging from 25 to 1000 km. The iteration between these two parts of the inversion converges in about 60 steps. The average attenuation parameters obtained from the inversion were Q = 1997 ± 10 and γ = 0.998 ± 0.003. The most pronounced variation from this average attenuation is a marked deamplification of more than a factor of 2 at 63 km and 2 Hz, which shallows with increasing frequency and increasing distance out to 200 km. The site-response spectra obtained for the ECTN stations are generally flat. The source spectral shape assumed in this inversion provides an adequate spectral model for the smaller events (Mo < 3 × 1021 dyne-cm) in the data set, whose Brune stress drops range from 5 to 150 bars. For the five events in the data set with Mo ≧ 1023 dyne-cm, however, the source spectra obtained by regressing the residuals suggest that an ω2 spectrum is an inadequate model for the spectral shape. In particular, the corner frequencies for most of these large events appear to be split, so that the spectra exhibit an intermediate behavior (where |ü(ω)| is roughly proportional to ω).
","language":"English","publisher":"Seismological Society of America","doi":"10.1785/BSSA0840010001","usgsCitation":"Boatwright, J., 1994, Regional propagation characteristics and source parameters of earthquakes in northeastern North America: Bulletin of the Seismological Society of America, v. 84, no. 1, p. 1-15, https://doi.org/10.1785/BSSA0840010001.","productDescription":"15 p.","startPage":"1","endPage":"15","costCenters":[],"links":[{"id":339029,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"84","issue":"1","noUsgsAuthors":false,"publicationDate":"1994-02-01","publicationStatus":"PW","scienceBaseUri":"58e35f90e4b09da67997ecfa","contributors":{"authors":[{"text":"Boatwright, John 0000-0002-6931-5241 boat@usgs.gov","orcid":"https://orcid.org/0000-0002-6931-5241","contributorId":1938,"corporation":false,"usgs":true,"family":"Boatwright","given":"John","email":"boat@usgs.gov","affiliations":[{"id":237,"text":"Earthquake Science Center","active":true,"usgs":true}],"preferred":true,"id":688040,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70186459,"text":"70186459 - 1994 - Geochemical evidence for enhanced preservation of organic matter in the oxygen minimum zone of the continental margin of northern California during the Late Pleistocene","interactions":[],"lastModifiedDate":"2017-04-04T19:13:57","indexId":"70186459","displayToPublicDate":"1994-02-01T00:00:00","publicationYear":"1994","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":3002,"text":"Paleoceanography","active":true,"publicationSubtype":{"id":10}},"title":"Geochemical evidence for enhanced preservation of organic matter in the oxygen minimum zone of the continental margin of northern California during the Late Pleistocene","docAbstract":"The present upper water mass of the northeastern Pacific Ocean off California has a well-developed oxygen minimum zone between 600 and 1200 m wherein concentrations of dissolved oxygen are less than 0.5 mL/L. Even at such low concentrations of dissolved oxygen, benthic burrowing organisms are abundant enough to thoroughly bioturbate the surface and near-surface sediments. These macro organisms, together with micro organisms, also consume large quantities of organic carbon produced by large seasonal stocks of plankton in the overlying surface waters, which are supported by high concentrations of nutrients within the California Current upwelling system. In contrast to modern conditions of bioturbation, laminated sediments are preserved in upper Pleistocene sections of cores collected on the continental slope at water depths within the present oxygen minimum zone from at least as far north as the California-Oregon border and as far south as Point Conception. Comparison of sediment components in the laminae with those delivered to sediment traps as pelagic marine “snow” demonstrates that the dark-light lamination couplets are indeed annual (varves). These upper Pleistocene varved sediments contain more abundant lipid-rich “sapropelic” (type II) organic matter than the overlying bioturbated, oxidized Holocene sediments. The baseline of stable carbon isotopic composition of the organic matter in these slope cores does not change with time, indicating that the higher concentrations of type II organic matter in the varved sediments represent better preservation of organic matter rather than any change in the source of organic matter.
","language":"English","publisher":"Wiley","doi":"10.1029/93PA02829","usgsCitation":"Dean, W.E., Gardner, J., and Anderson, R.Y., 1994, Geochemical evidence for enhanced preservation of organic matter in the oxygen minimum zone of the continental margin of northern California during the Late Pleistocene: Paleoceanography, v. 9, no. 1, p. 47-61, https://doi.org/10.1029/93PA02829.","productDescription":"15 p. ","startPage":"47","endPage":"61","costCenters":[],"links":[{"id":339162,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"9","issue":"1","noUsgsAuthors":false,"publicationDate":"2010-05-04","publicationStatus":"PW","scienceBaseUri":"58e4b0b4e4b09da6799977b7","contributors":{"authors":[{"text":"Dean, Walter E. dean@usgs.gov","contributorId":1801,"corporation":false,"usgs":true,"family":"Dean","given":"Walter","email":"dean@usgs.gov","middleInitial":"E.","affiliations":[{"id":318,"text":"Geosciences and Environmental Change Science Center","active":true,"usgs":true}],"preferred":true,"id":688527,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Gardner, James V.","contributorId":61769,"corporation":false,"usgs":true,"family":"Gardner","given":"James V.","affiliations":[],"preferred":false,"id":688528,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Anderson, Roger Y.","contributorId":19251,"corporation":false,"usgs":true,"family":"Anderson","given":"Roger","email":"","middleInitial":"Y.","affiliations":[],"preferred":false,"id":688529,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70208175,"text":"70208175 - 1994 - Instream flows to assist the recovery of endangered fishes of the upper Colorado River basin","interactions":[],"lastModifiedDate":"2020-01-29T12:05:37","indexId":"70208175","displayToPublicDate":"1994-01-29T12:01:23","publicationYear":"1994","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1021,"text":"Biological Report","active":true,"publicationSubtype":{"id":10}},"title":"Instream flows to assist the recovery of endangered fishes of the upper Colorado River basin","docAbstract":"The riverine landscape of the upper Colorado River basin has been extensively modified by dams, diversions, revetments, and water abstractions. These changes, probably coupled with the introduction of many nonnative fishes, have compromised the existence of four of the native fishes (Colorado River squawfish Ptychocheilus lucius, humpback chub Gila cypha, bonytail chub Gila elegans, and razorback sucker Xyrauchen texanus) of the river system. Efforts to recover these endangered fishes have emphasized reregulation of flows to provide better habitat conditions than existed during the last half century, when ranges and abundances of the fishes declined significantly. Contention emerged, however, with regard to the efficacy of methods used by the U.S. Fish and Wildlife Service to justify flow recommendations to protect the endangered fishes. The purpose of this study was to review the science pertaining to the issue of flow provision, to identify critical uncertainties, and to provide recommendations for determining the instream flow needs of the endangered fishes.
","language":"English","usgsCitation":"Stanford, J.A., 1994, Instream flows to assist the recovery of endangered fishes of the upper Colorado River basin: Biological Report, v. 24, p. 47-47.","productDescription":"1 p.","startPage":"47","endPage":"47","costCenters":[],"links":[{"id":371715,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"24","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Stanford, J. A.","contributorId":79643,"corporation":false,"usgs":true,"family":"Stanford","given":"J.","email":"","middleInitial":"A.","affiliations":[],"preferred":false,"id":780823,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70208172,"text":"70208172 - 1994 - Habitat use by an endangered riverine fish and implications for species protection","interactions":[],"lastModifiedDate":"2020-01-29T11:55:26","indexId":"70208172","displayToPublicDate":"1994-01-29T11:49:43","publicationYear":"1994","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1471,"text":"Ecology of Freshwater Fish","active":true,"publicationSubtype":{"id":10}},"title":"Habitat use by an endangered riverine fish and implications for species protection","docAbstract":"We investigated habitat specificity of the amber darter (Percina antesella Williams & Etnier 1977), an imperiled fish from restricted portions of 2 rivers in the southeastern United States. Foraging amber darters occupied a narrow range of riffle habitat, consistently avoiding areas < 20 cm deep and with velocity < 10 cm. s−1 near the substrate, occupying areas with cobble or gravel substrate and average water‐column velocity of 30 to 70 cm. s−1. During low to moderate flows, approximately 20% or more of the study areas contained suitable habitat for the species. Amber darters appeared rare, and the numbers of individuals were uncorrelated with the concurrent availability of suitable habitat. Protecting the amber darter may require more than maintaining adequate depths and velocities over gravel‐cobble substrates. Until we understand the potential importance of migration and dispersal for maintaining small populations, suitable habitat should be maintained over the longest contiguous stream segments possible.
","language":"English","publisher":"Wiley","doi":"10.1111/j.1600-0633.1994.tb00106.x","usgsCitation":"Freeman, B.J., and Freeman, M., 1994, Habitat use by an endangered riverine fish and implications for species protection: Ecology of Freshwater Fish, v. 3, p. 49-58, https://doi.org/10.1111/j.1600-0633.1994.tb00106.x.","productDescription":"10p.","startPage":"49","endPage":"58","costCenters":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"links":[{"id":371714,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Georgia, Tennessee","otherGeospatial":"Conasauga River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -84.82337951660156,\n 34.94491019751147\n ],\n [\n -84.7463035583496,\n 34.94491019751147\n ],\n [\n -84.7463035583496,\n 35.000191114817824\n ],\n [\n -84.82337951660156,\n 35.000191114817824\n ],\n [\n -84.82337951660156,\n 34.94491019751147\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"3","noUsgsAuthors":false,"publicationDate":"2006-06-30","publicationStatus":"PW","contributors":{"authors":[{"text":"Freeman, B. J.","contributorId":8031,"corporation":false,"usgs":true,"family":"Freeman","given":"B.","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":780799,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Freeman, Mary 0000-0001-7615-6923 mcfreeman@usgs.gov","orcid":"https://orcid.org/0000-0001-7615-6923","contributorId":3528,"corporation":false,"usgs":true,"family":"Freeman","given":"Mary","email":"mcfreeman@usgs.gov","affiliations":[{"id":531,"text":"Patuxent Wildlife Research Center","active":true,"usgs":true}],"preferred":true,"id":780800,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70208159,"text":"70208159 - 1994 - Body composition dynamics of ruddy ducks during wing moult","interactions":[],"lastModifiedDate":"2020-01-29T10:23:51","indexId":"70208159","displayToPublicDate":"1994-01-29T10:16:20","publicationYear":"1994","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1176,"text":"Canadian Journal of Zoology","active":true,"publicationSubtype":{"id":10}},"title":"Body composition dynamics of ruddy ducks during wing moult","docAbstract":"A method was developed for indexing moulting costs in waterfowl based on intensity of moult and proportional mass of feathers in seven feather regions (ADJMOLT). This method was then applied to an examination of relations between moulting costs and size-adjusted body mass and composition of postbreeding male and female ruddy ducks (Oxyura jamaicensis) collected in southwestern Manitoba, 30 July – 24 August 1985. Moderate to heavy moult (25 to > 50% of moulting feathers) was recorded in all feather regions. The intensity of down moult was greater in males than in females, but no differences between sexes in moult score by contour feather region, overall mean moult score, or ADJMOLT were detected. Relations between ADJMOLT and body fat (FAT), liver protein (LIVER), and size-adjusted body mass (ADJMASS), body protein (ADJPROT), and leg and breast muscle protein (ADJLEG and ADJBR, respectively) were not influenced by sex, but there was a sex effect on the relation of ADJMOLT to gizzard mass (GIZZWT). ADJPROT and ADJBR were negatively associated with ADJMOLT, whereas female GIZZWT was positively related to ADJMOLT. ADJMASS, ADJLEG, FAT, and LIVER were unrelated to ADJMOLT. Female ruddy ducks were structurally smaller and had less ADJMASS, ADJPROT, ADJLEG, and FAT than males, but there were no sex-related differences in ADJBR. I found no evidence of nutritional stress in post-breeding ruddy ducks, but argue that stress associated with moult in waterfowl is most likely to occur in females, especially small-bodied species that are primarily herbivorous.
","language":"English","publisher":"Canadian Science Publishing","doi":"10.1139/z93-312","usgsCitation":"Hohman, W., 1994, Body composition dynamics of ruddy ducks during wing moult: Canadian Journal of Zoology, v. 71, no. 11, p. 2224-2228, https://doi.org/10.1139/z93-312.","productDescription":"5 p.","startPage":"2224","endPage":"2228","costCenters":[],"links":[{"id":371704,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"Canada","otherGeospatial":"Southwest Manitoba","volume":"71","issue":"11","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Hohman, W.L.","contributorId":82638,"corporation":false,"usgs":true,"family":"Hohman","given":"W.L.","affiliations":[],"preferred":false,"id":780765,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70208155,"text":"70208155 - 1994 - Bed material and numerical modeling in a grand bed stream","interactions":[],"lastModifiedDate":"2020-01-29T10:00:50","indexId":"70208155","displayToPublicDate":"1994-01-29T09:53:45","publicationYear":"1994","noYear":false,"publicationType":{"id":24,"text":"Conference Paper"},"publicationSubtype":{"id":19,"text":"Conference Paper"},"title":"Bed material and numerical modeling in a grand bed stream","docAbstract":"No abstract available.
","largerWorkType":{"id":24,"text":"Conference Paper"},"largerWorkTitle":"Hydraulic engineering '94 : Proceedings of the 1994 Conference","largerWorkSubtype":{"id":19,"text":"Conference Paper"},"conferenceTitle":"Hydraulic engineering '94","conferenceDate":"August 1-5, 1994","conferenceLocation":"Buffalo, New York","language":"English","publisher":"American Society of Civil Engineers","isbn":"\t0784400377","usgsCitation":"Milhous, R., 1994, Bed material and numerical modeling in a grand bed stream, in Hydraulic engineering '94 : Proceedings of the 1994 Conference, Buffalo, New York, August 1-5, 1994, p. 1055-1059.","productDescription":"5 p.","startPage":"1055","endPage":"1059","costCenters":[],"links":[{"id":371700,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Milhous, R.T.","contributorId":106845,"corporation":false,"usgs":true,"family":"Milhous","given":"R.T.","email":"","affiliations":[],"preferred":false,"id":780734,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":70201388,"text":"70201388 - 1994 - Coupling of volatile transport and internal heat flow on Triton","interactions":[],"lastModifiedDate":"2018-12-12T11:39:57","indexId":"70201388","displayToPublicDate":"1994-01-25T11:39:28","publicationYear":"1994","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2317,"text":"Journal of Geophysical Research E: Planets","active":true,"publicationSubtype":{"id":10}},"title":" Coupling of volatile transport and internal heat flow on Triton","docAbstract":"Recently Brown et al. (1991) showed that Triton's internal heat source could amount to 5–20% of the absorbed insolation on Triton, thus significantly affecting volatile transport and atmospheric pressure. Subsequently, Kirk and Brown (1991a) used simple analytical models of the effect of internal heat on the distribution of volatiles on Triton's surface, confirming the speculation of Brown et al. that Triton's internal heat flow could strongly couple to the surface volatile distribution. To further explore this idea, we present numerical models of the permanent distribution of nitrogen ice on Triton that include the effects of sunlight, the two‐dimensional distribution of internal heat flow, the coupling of internal heat flow to the surface distribution of nitrogen ice, and the finite viscosity of nitrogen ice. From these models we conclude that: (1) The strong vertical thermal gradient induced in Triton's polar caps by internal heat‐flow facilitates viscous spreading to lower latitudes, thus opposing the poleward transport of volatiles by sunlight, and, for plausible viscosities and nitrogen inventories, producing permanent caps of considerable latitudinal extent; (2) It is probable that there is a strong coupling between the surface distribution of nitrogen ice on Triton and internal heat flow; (3) Asymmetries in the spatial distribution of Triton's heat flow, possibly driven by large‐scale, volcanic activity or convection in Triton's interior, can result in permanent polar caps of unequal latitudinal extent, including the case of only one permanent polar cap; (4) Melting at the base of a permanent polar cap on Triton caused by internal heat flow can significantly enhance viscous spreading, and, as an alternative to the solid‐state greenhouse mechanism proposed by Brown et al. (1990), could provide the necessary energy, fluids, and/or gases to drive Triton's geyser‐like plumes; (5) The atmospheric collapse predicted to occur on Triton in the next 20 years (Spencer, 1990) may be plausibly avoided because of the large latitudinal extent expected for permanent polar caps on Triton.
","language":"English","publisher":"American Geophysical Union","publisherLocation":"Washington, D.C.","doi":"10.1029/93JE02618","usgsCitation":"Brown, R.H., and Kirk, R.L., 1994, Coupling of volatile transport and internal heat flow on Triton: Journal of Geophysical Research E: Planets, v. 99, no. E1, p. 1965-1981, https://doi.org/10.1029/93JE02618.","productDescription":"17 p.","startPage":"1965","endPage":"1981","costCenters":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"links":[{"id":360205,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"otherGeospatial":"Triton","volume":"99","issue":"E1","noUsgsAuthors":false,"publicationDate":"2012-09-21","publicationStatus":"PW","scienceBaseUri":"5c122c5be4b034bf6a856a27","contributors":{"authors":[{"text":"Brown, Robert H.","contributorId":147246,"corporation":false,"usgs":false,"family":"Brown","given":"Robert","email":"","middleInitial":"H.","affiliations":[],"preferred":false,"id":753937,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kirk, Randolph L. 0000-0003-0842-9226 rkirk@usgs.gov","orcid":"https://orcid.org/0000-0003-0842-9226","contributorId":2765,"corporation":false,"usgs":true,"family":"Kirk","given":"Randolph","email":"rkirk@usgs.gov","middleInitial":"L.","affiliations":[{"id":131,"text":"Astrogeology Science Center","active":true,"usgs":true}],"preferred":true,"id":753938,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70207649,"text":"70207649 - 1994 - 40Ar/39Ar chronology and volcanology of silicic volcanism in the Davis Mountains, Trans-Pecos Texas","interactions":[],"lastModifiedDate":"2020-06-05T13:48:31.012088","indexId":"70207649","displayToPublicDate":"1994-01-02T12:38:18","publicationYear":"1994","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1723,"text":"GSA Bulletin","active":true,"publicationSubtype":{"id":10}},"displayTitle":"40Ar/39Ar chronology and volcanology of silicic volcanism in the Davis Mountains, Trans-Pecos Texas","title":"40Ar/39Ar chronology and volcanology of silicic volcanism in the Davis Mountains, Trans-Pecos Texas","docAbstract":"Field studies and 40Ar/39Ar dating reveal that silicic volcanism in the Davis Mountains part of the Trans-Pecos Texas volcanic field occurred in six episodes at 0.3 m.y. intervals between 36.8 and 35.3 Ma. Additionally, two groups of silicic intrusions were emplaced at 34.6 and 32.8 Ma. This episodicity is similar to that determined for volcanic fields dominated by ash-flow tuffs, yet voluminous, extensive silicic lavas are considerably more abundant than tuffs in the Davis Mountains, by number of flows and by volume. The preponderance of voluminous silicic lavas over tuffs most likely reflects low water contents and high temperatures of the alkalic and commonly peralkaline Davis Mountains magmas.
The earliest episode, at 36.8 Ma, included a widespread and voluminous (possibly >1,000 km3) suite of rhyolite and quartz trachyte lavas, several rhyolite domes, and a strongly rheomorphic, peralkaline ash-flow tuff erupted from a caldera in the northern Davis Mountains. The lava suite extends well beyond the Davis Mountains. Silicic lavas of all episodes probably erupted from widespread, fissure vents. The 36.5 Ma episode consisted of rhyolite to quartz trachyte lavas, also extensive and voluminous (∼200 km3). The 36.3 Ma episode consisted of rhyolite to trachyte tuffs and lavas erupted from a central vent volcano in the southern Davis Mountains. The 35.9 Ma episode consisted of a single, moderately large (∼50 km3) rhyolite lava and a small-volume ash-flow tuff erupted from a caldera in the western Davis Mountains. Rocks emplaced during the 35.6 Ma episode were also rhyolites, including an enigmatic rock that may be strongly rheomorphic ash-flow tuff or a combination of tuff and lava, followed by definite lavas. The 35.3 Ma episode consisted of two ash-flow tuffs, one of which is strongly rheomorphic, and additional voluminous rhyolite lavas (∼120 km3). The rheomorphic tuff erupted from a caldera in the southwestern Davis Mountains. The source of the other tuff is probably in the western Davis Mountains.
Intermediate and mafic rocks are minor, except around the southeastern flank of the Davis Mountains, where basalt is abundant. Mafic lavas erupted only during gaps in the silicic activity and on the flanks of the Davis Mountains. Nevertheless, basaltic magma probably drove the silicic magmatism, either by differentiation or by crustal melting, and was present throughout the time of Davis Mountains activity but could not penetrate the low-density silicic magma chambers until they cooled and solidified. The time required for cooling and solidification appears to be 0.1-0.2 m.y.
","language":"English","publisher":"GSA","doi":"10.1130/0016-7606(1994)106<1359:AACAVO>2.3.CO;2","usgsCitation":", C., Kunk, M.J., and McIntosh, W.C., 1994, 40Ar/39Ar chronology and volcanology of silicic volcanism in the Davis Mountains, Trans-Pecos Texas: GSA Bulletin, v. 106, no. 11, p. 1359-1376, https://doi.org/10.1130/0016-7606(1994)106<1359:AACAVO>2.3.CO;2.","productDescription":"18 p.","startPage":"1359","endPage":"1376","costCenters":[{"id":243,"text":"Eastern Geology and Paleoclimate Science Center","active":true,"usgs":true},{"id":40020,"text":"Florence Bascom Geoscience Center","active":true,"usgs":true}],"links":[{"id":370942,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Texas","otherGeospatial":"Davis Mountains","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -103.974609375,\n 29.916852233070173\n ],\n [\n -101.7333984375,\n 29.916852233070173\n ],\n [\n -101.7333984375,\n 31.93351676190369\n ],\n [\n -103.974609375,\n 31.93351676190369\n ],\n [\n -103.974609375,\n 29.916852233070173\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"106","issue":"11","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":" Christopher D. Henry","contributorId":126897,"corporation":false,"usgs":false,"given":"Christopher D. Henry","affiliations":[{"id":6689,"text":"Nevada Bureau of Mines and Geology","active":true,"usgs":false}],"preferred":false,"id":778749,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Kunk, Michael J. 0000-0003-4424-7825 mkunk@usgs.gov","orcid":"https://orcid.org/0000-0003-4424-7825","contributorId":200968,"corporation":false,"usgs":true,"family":"Kunk","given":"Michael","email":"mkunk@usgs.gov","middleInitial":"J.","affiliations":[{"id":40020,"text":"Florence Bascom Geoscience Center","active":true,"usgs":true},{"id":243,"text":"Eastern Geology and Paleoclimate Science Center","active":true,"usgs":true}],"preferred":true,"id":778750,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"McIntosh, W. C.","contributorId":68039,"corporation":false,"usgs":true,"family":"McIntosh","given":"W.","email":"","middleInitial":"C.","affiliations":[],"preferred":false,"id":778751,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":20897,"text":"ofr94276 - 1994 - Fate and pathways of injection-well effluent in the Florida Keys","interactions":[],"lastModifiedDate":"2022-01-04T18:45:00.293289","indexId":"ofr94276","displayToPublicDate":"1994-01-01T22:00:00","publicationYear":"1994","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":330,"text":"Open-File Report","code":"OFR","onlineIssn":"2331-1258","printIssn":"0196-1497","active":true,"publicationSubtype":{"id":5}},"seriesNumber":"94-276","title":"Fate and pathways of injection-well effluent in the Florida Keys","docAbstract":"Twenty-four wells (21 locations) were core drilled into the limestone beneath the Keys, reef tract, and outer reefs to determine if sewage effluents injected in Class V wells onshore are reaching offshore reef areas via underground flow. These wells were fitted with PVC casings and well screens and were sampled every three months for a period of one year. Analyses showed consistent hypersalinity in most wells and a marked increase in nitrogen (as ammonia) in offshore ground water. Other forms of nitrogen (NO2 and NO3) and phosphorous were not particularly elevated in offshore ground water but were above the levels found in surface marine water. The highest levels of nitrogen (NO2 and NO3 ) and phosphorous were in shallow onshore ground waters. Sources for the nutrients in the shallow onshore ground water consist of septic tanks and cesspools (@ 24,000 and 5,000 in the Florida Keys, respectively), agricultural fertilizers, and natural vegetation. Ammonia concentrations were low in shallow ground waters beneath the Florida Keys, probably because of oxidizing conditions.
Tidal pumping is particularly active, especially nearshore. Hydraulic heads sufficient to elevate well water as much as 7 cm above sea level during falling tides were detected in all nearshore wells. During rising tides, the situation was reversed and water flowed into the wells. Tidal pumping implies considerable water movement both in and out of the upper few meters of limestone. Tidal pumping is a likely mechanism for mixing and transferring nutrient-rich ground water into the overlying marine waters. Although tidal pumping should cause rather complete mixing and dilution of any freshwater-based effluents entering the limestone via the more than 600 disposal wells in the Florida Keys, the ground waters in the 30- to 40-ft-depth range (9-12 m) nevertheless remained slightly hypersaline relative to sea water throughout the year.
Fecal coliform and fecal streptococcal bacteria were associated with three Lower Keys offshore wells and two shallow onshore wells at Key Largo. On occasions, these bacteria were detected farther offshore, once in a well 4 miles off Key Largo. The bacterial analyses for Key Largo (both onshore and offshore) are supported by two independent bacteriological researchers using more sophisticated methods than the standard 100-ml membrane-filter method used in this study. Fecal bacteria can serve as tracers; thus, we conclude their presence is possible evidence for offshore transport of ground waters originating on Key Largo. Elevated nutrients (ammonia) and slightly elevated dissolved total phosphorous in offshore ground waters, however, cannot be tied to onshore sources with existing data.
Rock analyses of material from our cores do not prove or disprove the hypothesis that limestone beneath the Keys or reef tract is serving as a sink for phosphorus or other nutrients. The data, however, do not rule out phosphorus uptake by limestone adjacent to disposal sources. For the purposes of this study, monitoring wells were not positioned sufficiently close to injection wells to determine if uptake of phosphorous is taking place. Ground waters were found to contain more dissolved solids than could be accounted for if hypersalinity resulted from simple evaporation of sea water. These data indicate that ground waters in the vicinity of our wells are dissolving solids from the rock rather than precipitating material within the rock framework; however, as mentioned above, our wells were not positioned sufficiently close to disposal wells to determine if localized uptake is occurring.
Examination of rock cores from these wells revealed a general distribution of reef- and grainstone-facies belts. The Upper and Middle Keys are composed of a thin coral reef facies that extends only a few hundred feet seaward of the Keys. Reef facies give way to mudstone facies within a few yards of shore on the Florida Bay side of the Keys. On the seaward side of the Keys, beneath Hawk Channel and White Bank, the Pleistocene limestone is a mixed grainstone, packstone, and wackstone facies. Corals are rare or absent. The Pleistocene limestone beneath the outer reefs 4 to 5 miles offshore, however, consists of reef facies with the same coral fauna as that found on Key Largo. This pattern of two major reef-facies belts separated by a 2- to 4-mile-wide belt of grainstone facies may have as yet undetermined effects on groundwater circulation beneath the Florida reef tract. Grainstone is approximately an order of magnitude less permeable than the coralline Key Largo Limestone facies.
The Q3 surface, a major subsurface unconformity thought to form an effective confining zone elsewhere in south Florida, was not detected in wells drilled more than 1 mile from shore. This unconformity, however, was detected in all wells drilled on or near the Keys. What was found to be a more effective and widespread confining layer is the Holocene sediment deposited on the Pleistocene limestone during the past 6,000 to 7,000 years. These relatively impermeable sediments are extensive, forming a belt up to 5 miles wide beginning about 0.5 mile offshore. Holocene sediments generally consist of low-permeability lime mud just above the Pleistocene surface, overlain by more permeable carbonate sands and reefs. Leakage of ground water by tidal pumping is not likely to occur through lime-mud-dominated areas such as Hawk Channel but is likely to occur through isolated porous and permeable Holocene reefs situated on Pleistocene limestone highs, and in places where Holocene sediment does not cover the limestone bedrock. Leakage is therefore limited to 1) a shallow-water 0.5-mile-wide nearshore belt of exposed Key Largo Limestone, 2) Holocene patch reefs, which grow on mud-free topographic rock highs, and 3) along the seaward side of the outermost reef in 35 to 65 ft (10-20 m) of water, where Holocene reef and sediment accumulations are thin or absent.
This study did not address direct measurements of lateral groundwater movement or a hydrologic mechanism for transporting hypersaline ground water away from the Florida Keys. More recent work, however (Halley et al., 1994), shows that sea level in Florida Bay is higher than on the Atlantic side of the Keys more than 50% of the time. Higher sea level on the bay side of the Keys provides a potential for groundwater flow toward the Atlantic most of the time. Use of tracers (dyes or harmless bacteriological tracers) injected into the center of tightly spaced clusters of monitoring wells is a simple way to ascertain the net direction and rate of groundwater movement. Knowing the direction and rate of groundwater movement is needed for prediction and modeling efforts in the future
","language":"English","publisher":"U.S. Geological Survey","doi":"10.3133/ofr94276","collaboration":"Prepared in cooperation with NOAA Sanctuaries Reserves Division, NOAA National Underwater Research Program, Florida Keys Sanctuary Advisory Committee","usgsCitation":"Shinn, E., Reese, R.S., and Reich, C.D., 1994, Fate and pathways of injection-well effluent in the Florida Keys: U.S. Geological Survey Open-File Report 94-276, v, 116 p., https://doi.org/10.3133/ofr94276.","productDescription":"v, 116 p.","costCenters":[{"id":27821,"text":"Caribbean-Florida Water Science Center","active":true,"usgs":true}],"links":[{"id":50491,"rank":299,"type":{"id":11,"text":"Document"},"url":"https://pubs.usgs.gov/of/1994/0276/ofr94276.pdf","text":"Report","size":"8.90 MB","linkFileType":{"id":1,"text":"pdf"},"description":"Report"},{"id":153559,"rank":0,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/of/1994/0276/report-thumb.jpg"}],"country":"United States","state":"Florida","otherGeospatial":"Florida Keys","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -82.20794677734374,\n 24.477150011148677\n ],\n [\n -81.727294921875,\n 24.467150664739002\n ],\n [\n -81.18896484375,\n 24.58459276519208\n ],\n [\n -80.64239501953125,\n 24.816653556469955\n ],\n [\n -80.36773681640625,\n 25.0383270525352\n ],\n [\n -80.17822265625,\n 25.341543769441667\n ],\n [\n -80.14801025390625,\n 25.527571660479637\n ],\n [\n -80.22491455078125,\n 25.527571660479637\n ],\n [\n -80.26885986328125,\n 25.43087300404471\n ],\n [\n -80.42266845703124,\n 25.232273973019627\n ],\n [\n -80.55450439453125,\n 25.22978942503438\n ],\n [\n -80.6781005859375,\n 25.13533901613099\n ],\n [\n -81.1065673828125,\n 25.07316070640961\n ],\n [\n -81.20269775390624,\n 25.175116531621764\n ],\n [\n -82.20794677734374,\n 24.749325626697196\n ],\n [\n -82.20794677734374,\n 24.477150011148677\n ]\n ]\n ]\n }\n }\n ]\n}","contact":"Caribbean-Florida Water Science Center
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Two mechanistic models—which are unlike the traditional plate-tectonic landfill models used for most proposed Pangea reconstructions of the Yucatán block—relate the Mesozoic opening of the Gulf of Mexico directly to the movement of the North and South American plates: (1) a previous piggyback model in which Yucatán moves with South America out of the western gulf and (2) a new edge-driven model in which the motion of the Yucatán block is caused by forces applied to its margins by the movement of the North and South American plates. In the second model, Yucatán moves out of the northern Gulf of Mexico as a gear or roller bearing. On the basis of magnetic edge anomalies around the gulf, this edge-driven model predicts that from the Bathonian to Tithonian (∼170 to ∼150 Ma), Yucatán was rotated ∼60° counterclockwise as a rigid block between North and South America with rift propagation and extension occurring simultaneously in the Gulf of Mexico and Yucatan Basin.
","language":"English","publisher":"Geological Society of America","publisherLocation":"Boulder, CO","doi":"10.1130/0091-7613(1994)022<0507:MSTTOO>2.3.CO;2","usgsCitation":"Schouten, H., and Klitgord, K.D., 1994, Mechanistic solutions to the opening of the Gulf of Mexico: Geology, v. 22, no. 6, p. 507-510, https://doi.org/10.1130/0091-7613(1994)022<0507:MSTTOO>2.3.CO;2.","productDescription":"4 p.","startPage":"507","endPage":"510","onlineOnly":"N","additionalOnlineFiles":"N","costCenters":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"links":[{"id":296607,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"otherGeospatial":"Gulf of Mexico","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"type\": \"Polygon\",\n \"coordinates\": [\n [\n [\n -100.6787109375,\n 14.136575651477944\n ],\n [\n -80.771484375,\n 14.136575651477944\n ],\n [\n -80.771484375,\n 32.10118973232094\n ],\n [\n -100.6787109375,\n 32.10118973232094\n ],\n [\n -100.6787109375,\n 14.136575651477944\n ]\n ]\n ]\n }\n }\n ]\n}","volume":"22","issue":"6","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"548ace3ee4b00f366bee37bd","contributors":{"authors":[{"text":"Schouten, Hans","contributorId":64474,"corporation":false,"usgs":true,"family":"Schouten","given":"Hans","affiliations":[],"preferred":false,"id":526967,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Klitgord, Kim D.","contributorId":82307,"corporation":false,"usgs":true,"family":"Klitgord","given":"Kim","email":"","middleInitial":"D.","affiliations":[{"id":678,"text":"Woods Hole Coastal and Marine Science Center","active":true,"usgs":true}],"preferred":false,"id":526968,"contributorType":{"id":1,"text":"Authors"},"rank":2}]}} ,{"id":70199607,"text":"70199607 - 1994 - Field and modeling studies of multiphase fluid flow at the Bemidji, Minnesota crude-oil spill site","interactions":[],"lastModifiedDate":"2018-09-21T10:18:28","indexId":"70199607","displayToPublicDate":"1994-01-01T10:17:16","publicationYear":"1994","noYear":false,"publicationType":{"id":5,"text":"Book chapter"},"publicationSubtype":{"id":24,"text":"Book Chapter"},"title":"Field and modeling studies of multiphase fluid flow at the Bemidji, Minnesota crude-oil spill site","docAbstract":"No abstract available.
","largerWorkType":{"id":4,"text":"Book"},"largerWorkTitle":"Toxic substances and the hydrologic sciences","language":"English","publisher":"American Institute of Hydrology","publisherLocation":"Minneapolis, MN","usgsCitation":"Essaid, H.I., Herkelrath, W.N., and Dillard, L., 1994, Field and modeling studies of multiphase fluid flow at the Bemidji, Minnesota crude-oil spill site, chap. of Toxic substances and the hydrologic sciences, p. 52-68.","productDescription":"17 p.","startPage":"52","endPage":"68","costCenters":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true},{"id":589,"text":"Toxic Substances Hydrology Program","active":true,"usgs":true}],"links":[{"id":357613,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"5c11137fe4b034bf6a813ecd","contributors":{"editors":[{"text":"Dutton, A.R.","contributorId":93976,"corporation":false,"usgs":true,"family":"Dutton","given":"A.R.","email":"","affiliations":[],"preferred":false,"id":745964,"contributorType":{"id":2,"text":"Editors"},"rank":1}],"authors":[{"text":"Essaid, Hedeff I. 0000-0003-0154-8628 hiessaid@usgs.gov","orcid":"https://orcid.org/0000-0003-0154-8628","contributorId":2284,"corporation":false,"usgs":true,"family":"Essaid","given":"Hedeff","email":"hiessaid@usgs.gov","middleInitial":"I.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":745961,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Herkelrath, William N. 0000-0002-6149-5524 wnherkel@usgs.gov","orcid":"https://orcid.org/0000-0002-6149-5524","contributorId":2612,"corporation":false,"usgs":true,"family":"Herkelrath","given":"William","email":"wnherkel@usgs.gov","middleInitial":"N.","affiliations":[{"id":438,"text":"National Research Program - Western Branch","active":true,"usgs":true}],"preferred":true,"id":745962,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Dillard, L.A.","contributorId":32695,"corporation":false,"usgs":true,"family":"Dillard","given":"L.A.","email":"","affiliations":[],"preferred":false,"id":745963,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70129514,"text":"70129514 - 1994 - Neural networks for river flow prediction","interactions":[],"lastModifiedDate":"2024-04-19T19:32:53.031316","indexId":"70129514","displayToPublicDate":"1994-01-01T09:11:00","publicationYear":"1994","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":2230,"text":"Journal of Computing in Civil Engineering","active":true,"publicationSubtype":{"id":10}},"title":"Neural networks for river flow prediction","docAbstract":"The surface‐water hydrographs of rivers exhibit large variations due to many natural phenomena. One of the most commonly used approaches for interpolating and extending streamflow records is to fit observed data with an analytic power model. However, such analytic models may not adequately represent the flow process, because they are based on many simplifying assumptions about the natural phenomena that influence the river flow. This paper demonstrates how a neural network can be used as an adaptive model synthesizer as well as a predictor. Issues such as selecting an appropriate neural network architecture and a correct training algorithm as well as presenting data to neural networks are addressed using a constructive algorithm called the cascade‐correlation algorithm. The neural‐network approach is applied to the flow prediction of the Huron River at the Dexter sampling station, near Ann Arbor, Mich. Empirical comparisons are performed between the predictive capability of the neural network models and the most commonly used analytic nonlinear power model in terms of accuracy and convenience of use. Our preliminary results are quite encouraging. An analysis performed on the structure of the networks developed by the cascade‐correlation algorithm shows that the neural networks are capable of adapting their complexity to match changes in the flow history and that the models developed by the neural‐network approach are more complex than the power model.
","language":"English","publisher":"American Society of Civil Engineers","publisherLocation":"New York, NY","doi":"10.1061/(ASCE)0887-3801(1994)8:2(201)","usgsCitation":"Karunanithi, N., Grenney, W.J., Whitley, D., and Bovee, K., 1994, Neural networks for river flow prediction: Journal of Computing in Civil Engineering, v. 8, no. 2, p. 201-203, https://doi.org/10.1061/(ASCE)0887-3801(1994)8:2(201).","productDescription":"3 p.","startPage":"201","endPage":"203","numberOfPages":"3","costCenters":[],"links":[{"id":295624,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"volume":"8","issue":"2","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"544a18eae4b04d2014abfb50","contributors":{"authors":[{"text":"Karunanithi, Nachimuthu","contributorId":335698,"corporation":false,"usgs":false,"family":"Karunanithi","given":"Nachimuthu","email":"","affiliations":[],"preferred":false,"id":899267,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Grenney, William J.","contributorId":103360,"corporation":false,"usgs":true,"family":"Grenney","given":"William","email":"","middleInitial":"J.","affiliations":[],"preferred":false,"id":899268,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"Whitley, Darrell","contributorId":335699,"corporation":false,"usgs":false,"family":"Whitley","given":"Darrell","email":"","affiliations":[],"preferred":false,"id":899269,"contributorType":{"id":1,"text":"Authors"},"rank":3},{"text":"Bovee, Ken","contributorId":23455,"corporation":false,"usgs":true,"family":"Bovee","given":"Ken","affiliations":[],"preferred":false,"id":899270,"contributorType":{"id":1,"text":"Authors"},"rank":4}]}} ,{"id":70244131,"text":"70244131 - 1994 - Hydrological controls on dissolved organic carbon during snowmelt in the Snake River near Montezuma, Colorado","interactions":[],"lastModifiedDate":"2023-06-02T14:26:45.076732","indexId":"70244131","displayToPublicDate":"1994-01-01T09:09:07","publicationYear":"1994","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1007,"text":"Biogeochemistry","active":true,"publicationSubtype":{"id":10}},"title":"Hydrological controls on dissolved organic carbon during snowmelt in the Snake River near Montezuma, Colorado","docAbstract":"A quantitative understanding of the factors controlling the variation of dissolved organic carbon (DOC) in headwater streams is of scientific concern for at least two reasons. First, quantifying the overall carbon budgets of lotic systems is needed for a fundamental understanding of these systems. Second, DOC interacts strongly with other dissolved substances (heavy metals in particular) and plays an important role in the transport of contaminants.
In the Snake River near Montezuma, Colorado, measurements of DOC from 1980 to 1986 show rapid decreases in concentration from a peak very early in the snowmelt period. Peak DOC concentrations occur approximately one month prior to peak discharge in the stream. The decline in DOC with time is approximately exponential, suggesting that a simple flushing mechanism can explain the response. We examined hydrological mechanisms to explain the observed variability of DOC in the Snake River by simulating the hydrological response of the catchment using TOPMODEL and routing the predicted flows through a simple model that accounted for temporal changes in DOC. Conceptually the DOC model represents a terrestrial (soil) reservoir in which DOC builds up during low flow periods and is flushed out by infiltrating meltwaters. The model reproduces the main features of the observed variation in DOC in the Snake River and thus lays the foundation for quantitatively linking hydrological processes with carbon cycling through upland catchments. Model results imply that a significant fraction of the soils in the Snake River catchment contribute DOC to the stream during peak discharge. Our work represents one of the first attempts to quantitatively describe the hydrological controls on DOC dynamics in a headwater stream. These controls are studied through the model by imposing mass balance constraints on both the flux of water through the various DOC source areas and the amount of DOC that can accumulate in these areas.
","language":"English","publisher":"Springer","doi":"10.1007/BF00024390","usgsCitation":"Hornberger, G., Bencala, K.E., and McKnight, D., 1994, Hydrological controls on dissolved organic carbon during snowmelt in the Snake River near Montezuma, Colorado: Biogeochemistry, v. 25, p. 147-165, https://doi.org/10.1007/BF00024390.","productDescription":"19 p.","startPage":"147","endPage":"165","costCenters":[],"links":[{"id":417691,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"}],"country":"United States","state":"Colorado","city":"Montezuma","otherGeospatial":"Snake River","geographicExtents":"{\n \"type\": \"FeatureCollection\",\n \"features\": [\n {\n \"type\": \"Feature\",\n \"properties\": {},\n \"geometry\": {\n \"coordinates\": [\n [\n [\n -105.88914773375578,\n 39.58470796615606\n ],\n [\n -105.88914773375578,\n 39.52241233777417\n ],\n [\n -105.8177176302345,\n 39.52241233777417\n ],\n [\n -105.8177176302345,\n 39.58470796615606\n ],\n [\n -105.88914773375578,\n 39.58470796615606\n ]\n ]\n ],\n \"type\": \"Polygon\"\n }\n }\n ]\n}","volume":"25","noUsgsAuthors":false,"publicationStatus":"PW","contributors":{"authors":[{"text":"Hornberger, G.M.","contributorId":68463,"corporation":false,"usgs":true,"family":"Hornberger","given":"G.M.","email":"","affiliations":[],"preferred":false,"id":874554,"contributorType":{"id":1,"text":"Authors"},"rank":1},{"text":"Bencala, Kenneth E. kbencala@usgs.gov","contributorId":1541,"corporation":false,"usgs":true,"family":"Bencala","given":"Kenneth","email":"kbencala@usgs.gov","middleInitial":"E.","affiliations":[],"preferred":true,"id":874555,"contributorType":{"id":1,"text":"Authors"},"rank":2},{"text":"McKnight, D.M.","contributorId":189736,"corporation":false,"usgs":false,"family":"McKnight","given":"D.M.","email":"","affiliations":[],"preferred":false,"id":874556,"contributorType":{"id":1,"text":"Authors"},"rank":3}]}} ,{"id":70129510,"text":"70129510 - 1994 - Wilderness monitoring and data management","interactions":[],"lastModifiedDate":"2014-10-23T08:45:31","indexId":"70129510","displayToPublicDate":"1994-01-01T08:44:45","publicationYear":"1994","noYear":false,"publicationType":{"id":2,"text":"Article"},"publicationSubtype":{"id":10,"text":"Journal Article"},"seriesTitle":{"id":1567,"text":"Environmental Software","active":true,"publicationSubtype":{"id":10}},"title":"Wilderness monitoring and data management","docAbstract":"In the last decade, increased public interest in natural areas has resulted in increased monitoring activity by federal wilderness managers to assess the status of wilderness values. Wilderness values are those large-scale entities of wilderness which comprise, in sum, wilderness character. Data collected through wilderness monitoring must support the maintenance of wilderness values. Wilderness monitoring must include the development of clear data management strategies and provisions for hypothesis testing. Unfortunately, some monitoring programs do not support the status assessment of wilderness values. Often wilderness monitoring programs have neglected even the most rudimentary principles of data management. This paper presents a model for wilderness monitoring, guidelines for data management, and an overview of a PC-compatible wilderness monitoring data base, the Monitoring Information Data Analysis System (MIDAS).","largerWorkType":{"id":2,"text":"Article"},"largerWorkTitle":"Environmental Software","largerWorkSubtype":{"id":10,"text":"Journal Article"},"language":"English","publisher":"Elsevier Science Ltd.","publisherLocation":"Oxford","doi":"10.1016/0266-9838(94)90021-3","usgsCitation":"Riebau, A.R., 1994, Wilderness monitoring and data management: Environmental Software, v. 9, no. 4, p. 227-232, https://doi.org/10.1016/0266-9838(94)90021-3.","productDescription":"6 p.","startPage":"227","endPage":"232","numberOfPages":"6","costCenters":[],"links":[{"id":295619,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/outside_thumb.jpg"},{"id":295618,"type":{"id":10,"text":"Digital Object Identifier"},"url":"https://dx.doi.org/10.1016/0266-9838(94)90021-3"}],"volume":"9","issue":"4","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"544a191be4b04d2014abfb85","contributors":{"authors":[{"text":"Riebau, A. R.","contributorId":96203,"corporation":false,"usgs":true,"family":"Riebau","given":"A.","email":"","middleInitial":"R.","affiliations":[],"preferred":false,"id":503740,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ,{"id":60884,"text":"mf2252 - 1994 - Shoreline and coastal wetland variability along the west shore of Green Bay, Marinette and Oconto counties, Wisconsin","interactions":[],"lastModifiedDate":"2025-06-10T13:14:25.110519","indexId":"mf2252","displayToPublicDate":"1994-01-01T07:00:00","publicationYear":"1994","noYear":false,"publicationType":{"id":18,"text":"Report"},"publicationSubtype":{"id":5,"text":"USGS Numbered Series"},"seriesTitle":{"id":325,"text":"Miscellaneous Field Studies Map","code":"MF","active":false,"publicationSubtype":{"id":5}},"seriesNumber":"2252","title":"Shoreline and coastal wetland variability along the west shore of Green Bay, Marinette and Oconto counties, Wisconsin","docAbstract":"Coastal wetland ecosystems along the Great Lakes shorelines are extremely valuable natural resources. They provide numerous environmental and recreational benefits, and they serve as critical habitats for fish and wildlife populations. In general terms, wetlands can be defined as lands transitional between terrestrial and aquatic systems; they are characterized by periodic submergence or a water table at or near the surface and a predominance of hydric soils and hydrophytes. Changes in shoreline positions over time result in concomitant changes in the amount of adjacent coastal wetlands, frequently resulting in a permanent loss of these valuable resources. In the Great Lakes region, the main natural cause of shoreline changes are lake-level fluctuations that result from two interactive factors. One factor is the glacio-isostatic rebound of the lake basins, which has been occurring since the end of the late Wisconsin glaciation to the present. This crustal rebounding has slowly uplifted previous lake outlets, warped and tilted lake basins, and changed lake levels and shoreline positions. On the basis of historic lake-level gauge records, measured modern differential vertical uplift rates range from 0.26 ft/century in the southern part of the Great Lakes drainage basin to 1.74 ft/century in the northern part of the basin (Larsen, 1989). The second factor contributing to lake-level fluctuations is climate variability, which controls the amount of regional precipitation and evaporation, storm frequency, runoff, and resulting lake levels. Climate variability can occur over a wide spectrum of time scales; it can range from seasonal variations, to long-term trends of a few years or decades in duration, to trends lasting hundred of thousands of years. Climatic variations, in conjunction with glacio-isostatic rebound, have resulted in substantial temporal variability of the Great Lakes shorelines and associated wetland tracts during post-glacial times.","language":"English","publisher":"U.S. Geological Survey","publisherLocation":"Reston, VA","doi":"10.3133/mf2252","usgsCitation":"Shideler, G.L., 1994, Shoreline and coastal wetland variability along the west shore of Green Bay, Marinette and Oconto counties, Wisconsin: U.S. Geological Survey Miscellaneous Field Studies Map 2252, 1 Plate: 45.29 x 40.80 inches, https://doi.org/10.3133/mf2252.","productDescription":"1 Plate: 45.29 x 40.80 inches","costCenters":[],"links":[{"id":183493,"rank":1,"type":{"id":24,"text":"Thumbnail"},"url":"https://pubs.usgs.gov/thumbnails/mf2252.png"},{"id":284457,"rank":2,"type":{"id":17,"text":"Plate"},"url":"https://pubs.usgs.gov/mf/2252/plate-1.pdf","linkFileType":{"id":5,"text":"html"}},{"id":490274,"rank":3,"type":{"id":36,"text":"NGMDB Index Page"},"url":"https://ngmdb.usgs.gov/Prodesc/proddesc_5874.htm","linkFileType":{"id":5,"text":"html"}}],"scale":"24000","datum":"National Geodetic Vertical Datum 1929","country":"United States","state":"Wisconsin","county":"Marinette County, Oconto County","city":"Green Bay","geographicExtents":"{ \"type\": \"FeatureCollection\", \"features\": [ { \"type\": \"Feature\", \"properties\": {}, \"geometry\": { \"type\": \"Polygon\", \"coordinates\": [ [ [ -88.58,44.5 ], [ -88.58,45.0 ], [ -87.37,45.0 ], [ -87.37,44.5 ], [ -88.58,44.5 ] ] ] } } ] }","noUsgsAuthors":false,"publicationStatus":"PW","scienceBaseUri":"53cd72a1e4b0b290851086f0","contributors":{"authors":[{"text":"Shideler, Gerald L.","contributorId":89137,"corporation":false,"usgs":true,"family":"Shideler","given":"Gerald","email":"","middleInitial":"L.","affiliations":[],"preferred":false,"id":264553,"contributorType":{"id":1,"text":"Authors"},"rank":1}]}} ]}