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• 1. [Article] Geochronology of age-progressive volcanism of the Oregon High Lava Plains : implications for the plume interpretation of Yellowstone

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Geochronology of age-progressive volcanism of the Oregon High Lava Plains : implications for the plume interpretation of Yellowstone Author: Deino, Alan L., Grunder, Anita L., Duncan, Robert A., Jordan, Brennan T. copyrighted by American Geophysical Union Title: Geochronology of age-progressive volcanism of the Oregon High Lava Plains : implications for the plume interpretation of Yellowstone Author: Deino, Alan L., Grunder, Anita L., Duncan, Robert A., Jordan, Brennan T. copyrighted by American Geophysical Union Close

• 2. [Article] Origin of the Louisville ridge and its relationship to the Eltanin Fracture Zone System

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Origin of the Louisville ridge and its relationship to the Eltanin Fracture Zone System Author: Watts, A. B., Weissel, J. K., Duncan, Robert A., Larson, R. L. copyrighted by American Geophysical Union Title: Origin of the Louisville ridge and its relationship to the Eltanin Fracture Zone System Author: Watts, A. B., Weissel, J. K., Duncan, Robert A., Larson, R. L. copyrighted by American Geophysical Union Close

• 3. [Article] Bimodal volcanism of the High Lava Plains and Northwestern Basin and Range of Oregon: Distribution and tectonic implications of age-progressive rhyolites

  This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1525-2027.

  Citation × Citation Citation Abstract Copy Title: Bimodal volcanism of the High Lava Plains and Northwestern Basin and Range of Oregon: Distribution and tectonic implications of age-progressive rhyolites Author: Ford, Mark T., Duncan, Robert A., Grunder, Anita L. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1525-2027. Title: Bimodal volcanism of the High Lava Plains and Northwestern Basin and Range of Oregon: Distribution and tectonic implications of age-progressive rhyolites Author: Ford, Mark T., Duncan, Robert A., Grunder, Anita L. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1525-2027. Close

• 4. [Article] Prolonged plume volcanism in the Caribbean Large Igneous Province: New insights from Curaçao and Haiti

  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/gc/.

  Citation × Citation Citation Abstract Copy Title: Prolonged plume volcanism in the Caribbean Large Igneous Province: New insights from Curaçao and Haiti Author: Krawl, Kyle, Kent, Adam J. R., Duncan, Robert A., Loewen, Matthew W. 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/gc/. Title: Prolonged plume volcanism in the Caribbean Large Igneous Province: New insights from Curaçao and Haiti Author: Krawl, Kyle, Kent, Adam J. R., Duncan, Robert A., Loewen, Matthew W. 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/gc/. Close

• 5. [Article] Implications of a nonlinear ⁴⁰Ar/³⁹Ar age progression along the Louisville seamount trail for models of fixed and moving hot spots

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Implications of a nonlinear ⁴⁰Ar/³⁹Ar age progression along the Louisville seamount trail for models of fixed and moving hot spots Author: Koppers, Anthony A. P., Steinberger, Bernhard, Duncan, Robert A. Copyrighted by American Geophysical Union. Title: Implications of a nonlinear ⁴⁰Ar/³⁹Ar age progression along the Louisville seamount trail for models of fixed and moving hot spots Author: Koppers, Anthony A. P., Steinberger, Bernhard, Duncan, Robert A. Copyrighted by American Geophysical Union. Close

• 6. [Article] Radiometric ages for basement rocks from the Emperor Seamounts, ODP Leg 197

  The Hawaiian-Emperor seamount chain is the ‘‘type’’ example of an age-progressive, hot spotgenerated intraplate volcanic lineament. However, our current knowledge of the age distribution within this province ...

  Citation × Citation Citation Abstract Copy Title: Radiometric ages for basement rocks from the Emperor Seamounts, ODP Leg 197 Author: Keller, Randall A., Duncan, Robert A. The Hawaiian-Emperor seamount chain is the ‘‘type’’ example of an age-progressive, hot spotgenerated intraplate volcanic lineament. However, our current knowledge of the age distribution within this province is based largely on radiometric ages determined several decades ago. Improvements in instrumentation, sample preparation methods, and new material obtained by recent drilling warrant a reexamination of the age relations among the older Hawaiian volcanoes. We report new age determinations (40Ar-39Ar incremental heating method) on whole rocks and feldspar separates from Detroit (Sites 1203 and 1204), Nintoku (Site 1205), and Koko (Site 1206) Seamounts (Ocean Drilling Program (ODP) Leg 197) and Meiji Seamount (Deep Sea Drilling Project (DSDP) Leg 19, Site 192). Plateaus in incremental heating age spectra for Site 1203 lava flows give a mean age of 75.8 ± 0.6 (2s) Ma, which is consistent with the normal magnetic polarity directions observed and biostratigraphic age assignments. Site 1204 lavas produced discordant spectra, indicating Ar loss by reheating and K mobilization. Six plateau ages from lava flows at Site 1205 give a mean age of 55.6 ± 0.2 Ma, corresponding to Chron 24r. Drilling at Site 1206 intersected a N-R-N magnetic polarity sequence of lava flows, from which six plateau ages give a mean age of 49.1 ± 0.2 Ma, corresponding to the Chron 21n-22r-22n sequence. Plateau ages from two feldspar separates and one lava from DSDP Site 192 range from 34 to 41 Ma, significantly younger than the Cretaceous age of overlying sediments, which we relate to postcrystallization K mobilization. Combined with new dating results from Suiko Seamount (DSDP Site 433) and volcanoes near the prominent bend in the lineament [Sharp and Clague, 2002], the overall trend is increasing volcano age from south to north along the Emperor Seamounts, consistent with the hot spot model. However, there appear to be important departures from the earlier modeled simple linear age progression, which we relate to changes in Pacific plate motion and the rate of southward motion of the Hawaiian hot spot. Title: Radiometric ages for basement rocks from the Emperor Seamounts, ODP Leg 197 Author: Keller, Randall A., Duncan, Robert A. The Hawaiian-Emperor seamount chain is the ‘‘type’’ example of an age-progressive, hot spotgenerated intraplate volcanic lineament. However, our current knowledge of the age distribution within this province is based largely on radiometric ages determined several decades ago. Improvements in instrumentation, sample preparation methods, and new material obtained by recent drilling warrant a reexamination of the age relations among the older Hawaiian volcanoes. We report new age determinations (40Ar-39Ar incremental heating method) on whole rocks and feldspar separates from Detroit (Sites 1203 and 1204), Nintoku (Site 1205), and Koko (Site 1206) Seamounts (Ocean Drilling Program (ODP) Leg 197) and Meiji Seamount (Deep Sea Drilling Project (DSDP) Leg 19, Site 192). Plateaus in incremental heating age spectra for Site 1203 lava flows give a mean age of 75.8 ± 0.6 (2s) Ma, which is consistent with the normal magnetic polarity directions observed and biostratigraphic age assignments. Site 1204 lavas produced discordant spectra, indicating Ar loss by reheating and K mobilization. Six plateau ages from lava flows at Site 1205 give a mean age of 55.6 ± 0.2 Ma, corresponding to Chron 24r. Drilling at Site 1206 intersected a N-R-N magnetic polarity sequence of lava flows, from which six plateau ages give a mean age of 49.1 ± 0.2 Ma, corresponding to the Chron 21n-22r-22n sequence. Plateau ages from two feldspar separates and one lava from DSDP Site 192 range from 34 to 41 Ma, significantly younger than the Cretaceous age of overlying sediments, which we relate to postcrystallization K mobilization. Combined with new dating results from Suiko Seamount (DSDP Site 433) and volcanoes near the prominent bend in the lineament [Sharp and Clague, 2002], the overall trend is increasing volcano age from south to north along the Emperor Seamounts, consistent with the hot spot model. However, there appear to be important departures from the earlier modeled simple linear age progression, which we relate to changes in Pacific plate motion and the rate of southward motion of the Hawaiian hot spot. Close

• 7. [Article] Temporal and geochemical variability of volcanic products of the Marquesas hotspot

  copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Temporal and geochemical variability of volcanic products of the Marquesas hotspot Author: Desonie, Dana L., Duncan, Robert A., Natland, J. H. copyrighted by American Geophysical Union. Title: Temporal and geochemical variability of volcanic products of the Marquesas hotspot Author: Desonie, Dana L., Duncan, Robert A., Natland, J. H. copyrighted by American Geophysical Union. Close

• 8. [Article] Age progressive volcanism in the New England seamounts and the opening of the Central Atlantic Ocean

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Age progressive volcanism in the New England seamounts and the opening of the Central Atlantic Ocean Author: Duncan, Robert A. copyrighted by American Geophysical Union Title: Age progressive volcanism in the New England seamounts and the opening of the Central Atlantic Ocean Author: Duncan, Robert A. copyrighted by American Geophysical Union Close

• 9. [Article] Stratigraphy and age of the Eocene Igtertivâ Formation basalts, alkaline pebbles and sediments of the Kap Dalton Group in the graben at Kap Dalton, East Greenland

  This is the publisher’s final pdf. The published article is copyrighted by Dansk Geologisk Forening and can be found at: http://www.2dgf.dk/.

  Citation × Citation Citation Abstract Copy Title: Stratigraphy and age of the Eocene Igtertivâ Formation basalts, alkaline pebbles and sediments of the Kap Dalton Group in the graben at Kap Dalton, East Greenland Author: Pedersen, Asger K., Larsen, Lotte M., Watt, W. Stuart, Sorensen, Erik Vest, Duncan, Robert A. This is the publisher’s final pdf. The published article is copyrighted by Dansk Geologisk Forening and can be found at: http://www.2dgf.dk/. Title: Stratigraphy and age of the Eocene Igtertivâ Formation basalts, alkaline pebbles and sediments of the Kap Dalton Group in the graben at Kap Dalton, East Greenland Author: Pedersen, Asger K., Larsen, Lotte M., Watt, W. Stuart, Sorensen, Erik Vest, Duncan, Robert A. This is the publisher’s final pdf. The published article is copyrighted by Dansk Geologisk Forening and can be found at: http://www.2dgf.dk/. Close

• 10. [Article] Distribution of recent volcanism and the morphology of seamounts and ridges in the GLIMPSE study area: implications for the lithospheric cracking hypothesis for the origin of intraplate, non-hotspot volcanic chains

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Distribution of recent volcanism and the morphology of seamounts and ridges in the GLIMPSE study area: implications for the lithospheric cracking hypothesis for the origin of intraplate, non-hotspot volcanic chains Author: Scheirer, Daniel S., Forsyth, Donald W., Harmon, Nicholas, Duncan, Robert A. copyrighted by American Geophysical Union Title: Distribution of recent volcanism and the morphology of seamounts and ridges in the GLIMPSE study area: implications for the lithospheric cracking hypothesis for the origin of intraplate, non-hotspot volcanic chains Author: Scheirer, Daniel S., Forsyth, Donald W., Harmon, Nicholas, Duncan, Robert A. copyrighted by American Geophysical Union Close