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• 341. [Article] The ocean ecology of salmon in the Northeast Pacific Ocean : an abridged history

  Research on the ecology of salmon in the northeast Pacific Ocean began in the early 20th century. Charles Gilbert and Willis Rich demonstrated the basis for the stock concept and were instrumental in changing ...

  Citation × Citation Citation Abstract Copy Title: The ocean ecology of salmon in the Northeast Pacific Ocean : an abridged history Author: McKinnell, Stewart M., Pearcy, William G. Research on the ecology of salmon in the northeast Pacific Ocean began in the early 20th century. Charles Gilbert and Willis Rich demonstrated the basis for the stock concept and were instrumental in changing common misconceptions of the times. Later in the 1900s, research endeavors, primarily under the auspices of the International North Pacific Fisheries Commission, led to important studies on the distribution and migration of maturing salmon on the high seas. Research on the early juvenile period was initiated later, especially after the 1982-1983 El Niño clearly showed the limits of the ocean's carrying capacity along the west coast of the United States. There is now good evidence for both intra- and interspecific competition among salmon in the open ocean and for correlations between variable physical environments, such as El Ninos and regime shifts, and survival of salmon during early ocean life. How mortality rates are affected by physical forcing, food availability, predation, and food web structure and how these effects will be modified by climate change and global warming are all major challenges for the future. Title: The ocean ecology of salmon in the Northeast Pacific Ocean : an abridged history Author: McKinnell, Stewart M., Pearcy, William G. Research on the ecology of salmon in the northeast Pacific Ocean began in the early 20th century. Charles Gilbert and Willis Rich demonstrated the basis for the stock concept and were instrumental in changing common misconceptions of the times. Later in the 1900s, research endeavors, primarily under the auspices of the International North Pacific Fisheries Commission, led to important studies on the distribution and migration of maturing salmon on the high seas. Research on the early juvenile period was initiated later, especially after the 1982-1983 El Niño clearly showed the limits of the ocean's carrying capacity along the west coast of the United States. There is now good evidence for both intra- and interspecific competition among salmon in the open ocean and for correlations between variable physical environments, such as El Ninos and regime shifts, and survival of salmon during early ocean life. How mortality rates are affected by physical forcing, food availability, predation, and food web structure and how these effects will be modified by climate change and global warming are all major challenges for the future. Close

• 342. [Article] Feeding methane vents and gas hydrate deposits at south Hydrate Ridge

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Feeding methane vents and gas hydrate deposits at south Hydrate Ridge Author: Torres, Marta E., Liu, Xiaoli, Riedel, Michael, Bangs, Nathan Lawrence Bailey, Johnson, Joel E., Tréhu, Anne Martine, Flemings, Peter B., Gracia, Eulalia, Liu, C. S., Chevallier, Johanna Copyrighted by American Geophysical Union. Title: Feeding methane vents and gas hydrate deposits at south Hydrate Ridge Author: Torres, Marta E., Liu, Xiaoli, Riedel, Michael, Bangs, Nathan Lawrence Bailey, Johnson, Joel E., Tréhu, Anne Martine, Flemings, Peter B., Gracia, Eulalia, Liu, C. S., Chevallier, Johanna Copyrighted by American Geophysical Union. Close

• 343. [Article] The Cobb-Eickelberg seamount chain : hotspot volcanism with mid-oean ridge basalt affinity

  Cobb hotspot, currently located beneath Axial seamount on the Juan de Fuca ridge, has the temporal but not the isotopic characteristics usually attributed to a mantle plume. The earlier volcanic products ...

  Citation × Citation Citation Abstract Copy Title: The Cobb-Eickelberg seamount chain : hotspot volcanism with mid-oean ridge basalt affinity Author: Desonie, Dana L., Duncan, Robert A. Cobb hotspot, currently located beneath Axial seamount on the Juan de Fuca ridge, has the temporal but not the isotopic characteristics usually attributed to a mantle plume. The earlier volcanic products of the hotspot, from eight volcanoes in the Cobb-Eickelberg seamount (CES) chain, show a westward age progression away from the hotspot and a westward increase in the age difference between the seamounts and the crust on which they formed. These results are consistent with movement of the Pacific plate over a fixed Cobb hotspot and eventual encroachment by the westwardly migrating Juan de Fuca ridge. CES lavas are slightly enriched in alkalies and incompatible elements relative to those of the Juan de Fuca ridge but they have Sr. Nd, and Pb isotopic compositions virtually identical to those found along the ridge. Therefore, Cobb hotspot is a stationary, upper mantle melting anomaly whose volcanic products show strong mid-ocean ridge basalt (MORB) affinity. These observations can be explained by low degrees of partial melting of entrained heterogeneous upper mantle MORB source material within a thermally driven lower mantle diapir or by an intrinsic MORB-like composition of the deeper mantle source region from which northeast Pacific plumes rise. Title: The Cobb-Eickelberg seamount chain : hotspot volcanism with mid-oean ridge basalt affinity Author: Desonie, Dana L., Duncan, Robert A. Cobb hotspot, currently located beneath Axial seamount on the Juan de Fuca ridge, has the temporal but not the isotopic characteristics usually attributed to a mantle plume. The earlier volcanic products of the hotspot, from eight volcanoes in the Cobb-Eickelberg seamount (CES) chain, show a westward age progression away from the hotspot and a westward increase in the age difference between the seamounts and the crust on which they formed. These results are consistent with movement of the Pacific plate over a fixed Cobb hotspot and eventual encroachment by the westwardly migrating Juan de Fuca ridge. CES lavas are slightly enriched in alkalies and incompatible elements relative to those of the Juan de Fuca ridge but they have Sr. Nd, and Pb isotopic compositions virtually identical to those found along the ridge. Therefore, Cobb hotspot is a stationary, upper mantle melting anomaly whose volcanic products show strong mid-ocean ridge basalt (MORB) affinity. These observations can be explained by low degrees of partial melting of entrained heterogeneous upper mantle MORB source material within a thermally driven lower mantle diapir or by an intrinsic MORB-like composition of the deeper mantle source region from which northeast Pacific plumes rise. Close

• 344. [Article] A captured island chain in the coast range of Oregon and Washington

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: A captured island chain in the coast range of Oregon and Washington Author: Duncan, Robert A. copyrighted by American Geophysical Union Title: A captured island chain in the coast range of Oregon and Washington Author: Duncan, Robert A. copyrighted by American Geophysical Union Close

• 345. [Article] Elemental and isotopic abundance of noble gases in formation fluids recovered in situ from the Chile Triple Juction

  Sedimentary pore fluids from the Chile Triple Junction were sampled in situ, and analyzed for their noble gas composition. ³He/⁴He and ⁴He/Ne ratios were used to evaluate the fraction of helium in the ...

  Citation × Citation Citation Abstract Copy Title: Elemental and isotopic abundance of noble gases in formation fluids recovered in situ from the Chile Triple Juction Author: Torres, Marta E., Winckler, Gisela, Suckow, Axel, Bayer, Reinhold, Froelich, Philip N. Sedimentary pore fluids from the Chile Triple Junction were sampled in situ, and analyzed for their noble gas composition. ³He/⁴He and ⁴He/Ne ratios were used to evaluate the fraction of helium in the samples that originated from mantle and radiogenic sources. The results show no primordial helium in samples recovered from Sites 860 and 861. In contrast, a primordial component is present in two samples from a depth interval in Site 863 that corresponds to a zone of tectonic discontinuity. A decrease in the concentration of dissolved K, Sr, Mg, and SO₄ in this interval is consistent with the presence of a fluid which has been altered by basalt-seawater reactions. These results indicate lateral fluid migration from a hydrothermal source which is probably associated with the recently subducted Chile Ridge axis. Title: Elemental and isotopic abundance of noble gases in formation fluids recovered in situ from the Chile Triple Juction Author: Torres, Marta E., Winckler, Gisela, Suckow, Axel, Bayer, Reinhold, Froelich, Philip N. Sedimentary pore fluids from the Chile Triple Junction were sampled in situ, and analyzed for their noble gas composition. ³He/⁴He and ⁴He/Ne ratios were used to evaluate the fraction of helium in the samples that originated from mantle and radiogenic sources. The results show no primordial helium in samples recovered from Sites 860 and 861. In contrast, a primordial component is present in two samples from a depth interval in Site 863 that corresponds to a zone of tectonic discontinuity. A decrease in the concentration of dissolved K, Sr, Mg, and SO₄ in this interval is consistent with the presence of a fluid which has been altered by basalt-seawater reactions. These results indicate lateral fluid migration from a hydrothermal source which is probably associated with the recently subducted Chile Ridge axis. Close

• 346. [Article] Evolution of a coupled marine ice sheet-sea level model

  This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/jgr/.

  Citation × Citation Citation Abstract Copy Title: Evolution of a coupled marine ice sheet-sea level model Author: Mitrovica, Jerry X., Huybers, Peter, Pollard, David, Clark, Peter U., Gomez, Natalya This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/jgr/. Title: Evolution of a coupled marine ice sheet-sea level model Author: Mitrovica, Jerry X., Huybers, Peter, Pollard, David, Clark, Peter U., Gomez, Natalya This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/jgr/. Close

• 347. [Article] The effects of scattering-layer composition, animal size, and numerical density on the frequency response of volume backscatter

  Land-associated, sound-scattering layers of mesopelagic micronekton surround the Hawaiian Islands. These animals undergo diel migrations during which they split into multiple, distinct layers that have ...

  Citation × Citation Citation Abstract Copy Title: The effects of scattering-layer composition, animal size, and numerical density on the frequency response of volume backscatter Author: Benoit-Bird, Kelly J. Land-associated, sound-scattering layers of mesopelagic micronekton surround the Hawaiian Islands. These animals undergo diel migrations during which they split into multiple, distinct layers that have differences in animal density, taxonomic composition, and size. A video-camera system capable of quantitatively estimating the biological constituency of the layers was combined with a four-frequency, vessel-mounted, echosounder system (38, 70, 120, and 200 kHz) to examine the effects of layer features on the frequency response of volume backscatter. Volume scattering was correlated with animal density at all frequencies, but the effects of animal length and layer composition were frequency-specific. Only scattering at 70 kHz matched the predictions of volume scattering based on the mean echo strengths and densities estimated from camera profiles, suggesting different scattering mechanisms at other frequencies. Differences in volume scattering between pairs of frequencies, however, did strongly correlate with animal length and layer composition and could be used as measures of the biological properties of layers. Applying this technique to the data shows strong partitioning of habitat by taxa and animal size in space and time, indicating the importance of competition in structuring the community. Title: The effects of scattering-layer composition, animal size, and numerical density on the frequency response of volume backscatter Author: Benoit-Bird, Kelly J. Land-associated, sound-scattering layers of mesopelagic micronekton surround the Hawaiian Islands. These animals undergo diel migrations during which they split into multiple, distinct layers that have differences in animal density, taxonomic composition, and size. A video-camera system capable of quantitatively estimating the biological constituency of the layers was combined with a four-frequency, vessel-mounted, echosounder system (38, 70, 120, and 200 kHz) to examine the effects of layer features on the frequency response of volume backscatter. Volume scattering was correlated with animal density at all frequencies, but the effects of animal length and layer composition were frequency-specific. Only scattering at 70 kHz matched the predictions of volume scattering based on the mean echo strengths and densities estimated from camera profiles, suggesting different scattering mechanisms at other frequencies. Differences in volume scattering between pairs of frequencies, however, did strongly correlate with animal length and layer composition and could be used as measures of the biological properties of layers. Applying this technique to the data shows strong partitioning of habitat by taxa and animal size in space and time, indicating the importance of competition in structuring the community. Close

• 348. [Article] Seasonal variability in the Southwestern Atlantic

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Seasonal variability in the Southwestern Atlantic Author: Chelton, Dudley B., Schlax, Michael G., Matano, Ricardo P. copyrighted by American Geophysical Union Title: Seasonal variability in the Southwestern Atlantic Author: Chelton, Dudley B., Schlax, Michael G., Matano, Ricardo P. copyrighted by American Geophysical Union Close

• 349. [Article] Tree buffers along streams on western Oregon farmland

  Published October 2005. Reviewed March 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Tree buffers along streams on western Oregon farmland Author: Rogers, William Reinhold, Bishaw, Badege, Emmingham, William H., Oregon State University. Extension Service Published October 2005. Reviewed March 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Tree buffers along streams on western Oregon farmland Author: Rogers, William Reinhold, Bishaw, Badege, Emmingham, William H., Oregon State University. Extension Service Published October 2005. Reviewed March 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 350. [Article] Effects of physical factors on the vertical distribution of larval walleye pollock Theragra chalcogramma under controlled laboratory conditions

  The published version of this article is copyrighted by Inter-Research and can be found here: http://www.int-res.com/journals/meps/meps-home/

  Citation × Citation Citation Abstract Copy Title: Effects of physical factors on the vertical distribution of larval walleye pollock Theragra chalcogramma under controlled laboratory conditions Author: Olla, Bori L., Davis, Michael W. The published version of this article is copyrighted by Inter-Research and can be found here: http://www.int-res.com/journals/meps/meps-home/ Title: Effects of physical factors on the vertical distribution of larval walleye pollock Theragra chalcogramma under controlled laboratory conditions Author: Olla, Bori L., Davis, Michael W. The published version of this article is copyrighted by Inter-Research and can be found here: http://www.int-res.com/journals/meps/meps-home/ Close