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• 21. [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

• 22. [Article] Timing and composition of continental volcanism at Harrat Hutaymah, western Saudi Arabia

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier ...

  Citation × Citation Citation Abstract Copy Title: Timing and composition of continental volcanism at Harrat Hutaymah, western Saudi Arabia Author: Schlieder, Tyler D., Kent, Adam J.R., Duncan, Robert A., Thornber, Carl R., Al-Amri, Abdullah M. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/journal-of-volcanology-and-geothermal-research/ Title: Timing and composition of continental volcanism at Harrat Hutaymah, western Saudi Arabia Author: Schlieder, Tyler D., Kent, Adam J.R., Duncan, Robert A., Thornber, Carl R., Al-Amri, Abdullah M. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/journal-of-volcanology-and-geothermal-research/ Close

• 23. [Article] Five million years of compositionally diverse, episodic volcanism : construction of Davidson Seamount atop an abandoned spreading center

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Five million years of compositionally diverse, episodic volcanism : construction of Davidson Seamount atop an abandoned spreading center Author: Huard, J. J., Lonsdale, P., Davis, A. S., Paduan, J. B., Duncan, Robert A., Clague, D. A., DeVogelaere, Castillo, P. R. copyrighted by American Geophysical Union Title: Five million years of compositionally diverse, episodic volcanism : construction of Davidson Seamount atop an abandoned spreading center Author: Huard, J. J., Lonsdale, P., Davis, A. S., Paduan, J. B., Duncan, Robert A., Clague, D. A., DeVogelaere, Castillo, P. R. copyrighted by American Geophysical Union Close

• 24. [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

• 25. [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

• 26. [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

• 27. [Article] Radiometric dating of Young MORB using the ⁴⁰Ar-³⁹Ar incremental heating method

  copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Radiometric dating of Young MORB using the ⁴⁰Ar-³⁹Ar incremental heating method Author: Hogan, L. G., Duncan, Robert A. copyrighted by American Geophysical Union. Title: Radiometric dating of Young MORB using the ⁴⁰Ar-³⁹Ar incremental heating method Author: Hogan, L. G., Duncan, Robert A. copyrighted by American Geophysical Union. Close

• 28. [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

• 29. [Article] The timing and duration of the Karoo igneous event, southern Gondwana

  A volcanic event of immense scale occurred within a relatively short period in early Jurassic time over large regions of the contiguous Gondwana supercontinent. In southern Africa, associated remnants ...

  Citation × Citation Citation Abstract Copy Title: The timing and duration of the Karoo igneous event, southern Gondwana Author: Duncan, A.R., Duncan, Robert A., Marsh, J.S., Hooper, P.R., Rehacek, J. A volcanic event of immense scale occurred within a relatively short period in early Jurassic time over large regions of the contiguous Gondwana supercontinent. In southern Africa, associated remnants of thick volcanic successions of lava flows and extensive dike and sill complexes of similar composition have been grouped together as the Karoo Igneous Province. Correlative volcanic and plutonic rocks occur in Antarctica and Australia as the Ferrar Province. Thirty-two new Ar-40/Ar-39 incremental heating experiments on feldspars and whole rocks from Namibia, South Africa and East Antarctica produce highly resolved ages with a vast majority at 183 +/- 1 Ma and a total range of 184 to 179 Ma. These are indistinguishable from recent, high-resolution Ar-40/Ar-39 and U-Pb age determinations reported from the Antarctic portion of the province. Initial Karoo volcanism (Lesotho-type compositions) occurred across the entire South African craton. The ubiquitous distribution of a plexus of generally nonoriented feeder dikes and sills intruding Precambrian crystalline rocks and Phanerozoic sediments indicates that these magmas penetrated the craton over a broad region. Lithosphere thinning of the continent followed the main pulse of igneous activity, with volcanism focused in the Lebombo-Nuanetsi region, near the eventual split between Africa and Antarctica. Seafloor spreading and dispersion of east and west Gondwana followed some 10-20 m.y. afterward. The volume of the combined Karoo-Ferrar province (similar to 2.5 x 10(6) km(3)) makes it one of the largest continental flood basalt events. The timing of this event correlates with a moderate mass extinction (Toarcian-Aalenian), affecting largely marine invertebrates. This extinction event was not as severe as those recorded at the Permian-Triassic or Cretaceous-Tertiary boundaries associated with the Siberian and Deccan flood basalts events, respectively. The difference may be due to the high southerly latitude and somewhat lower eruption rates of the Karoo event. Title: The timing and duration of the Karoo igneous event, southern Gondwana Author: Duncan, A.R., Duncan, Robert A., Marsh, J.S., Hooper, P.R., Rehacek, J. A volcanic event of immense scale occurred within a relatively short period in early Jurassic time over large regions of the contiguous Gondwana supercontinent. In southern Africa, associated remnants of thick volcanic successions of lava flows and extensive dike and sill complexes of similar composition have been grouped together as the Karoo Igneous Province. Correlative volcanic and plutonic rocks occur in Antarctica and Australia as the Ferrar Province. Thirty-two new Ar-40/Ar-39 incremental heating experiments on feldspars and whole rocks from Namibia, South Africa and East Antarctica produce highly resolved ages with a vast majority at 183 +/- 1 Ma and a total range of 184 to 179 Ma. These are indistinguishable from recent, high-resolution Ar-40/Ar-39 and U-Pb age determinations reported from the Antarctic portion of the province. Initial Karoo volcanism (Lesotho-type compositions) occurred across the entire South African craton. The ubiquitous distribution of a plexus of generally nonoriented feeder dikes and sills intruding Precambrian crystalline rocks and Phanerozoic sediments indicates that these magmas penetrated the craton over a broad region. Lithosphere thinning of the continent followed the main pulse of igneous activity, with volcanism focused in the Lebombo-Nuanetsi region, near the eventual split between Africa and Antarctica. Seafloor spreading and dispersion of east and west Gondwana followed some 10-20 m.y. afterward. The volume of the combined Karoo-Ferrar province (similar to 2.5 x 10(6) km(3)) makes it one of the largest continental flood basalt events. The timing of this event correlates with a moderate mass extinction (Toarcian-Aalenian), affecting largely marine invertebrates. This extinction event was not as severe as those recorded at the Permian-Triassic or Cretaceous-Tertiary boundaries associated with the Siberian and Deccan flood basalts events, respectively. The difference may be due to the high southerly latitude and somewhat lower eruption rates of the Karoo event. Close

• 30. [Article] Spatial and temporal distribution of a C-like asthenoshpheric component in the Rano Rahi Seamount Field, East Pacific Rise, 15°-19°S

  copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Spatial and temporal distribution of a C-like asthenoshpheric component in the Rano Rahi Seamount Field, East Pacific Rise, 15°-19°S Author: Sinton, J. M., Mahoney, J. J., Duncan, Robert A., Hall, L. S. copyrighted by American Geophysical Union. Title: Spatial and temporal distribution of a C-like asthenoshpheric component in the Rano Rahi Seamount Field, East Pacific Rise, 15°-19°S Author: Sinton, J. M., Mahoney, J. J., Duncan, Robert A., Hall, L. S. copyrighted by American Geophysical Union. Close