@article{pollock_hibbard_2010, title={Geochemistry and tectonic significance of the Stony Mountain gabbro, North Carolina: Implications for the Early Paleozoic evolution of Carolinia}, volume={17}, ISSN={["1342-937X"]}, DOI={10.1016/j.gr.2009.09.009}, abstractNote={Carolinia comprises a collection of Neoproterozoic–Early Paleozoic magmatic arc and sedimentary terranes that were amalgamated and accreted to Laurentia in the early to middle Paleozoic. In central North Carolina, mafic rocks of the Stony Mountain gabbro intrude sub-aqueous volcanic and sedimentary rocks and submarine epiclastic sedimentary rocks of the Albemarle Group. The age of the Stony Mountain gabbro is constrained to the Early Cambrian–Middle Ordovician. Field relations indicate that the gabbro represents the final phase of magmatism following the eruption and deposition of the Neoproterozoic–earliest Cambrian Albemarle Group, yet the gabbro pre-dates regional metamorphism and tectonism related to the Late Ordovician accretion of Carolinia to Laurentia. The Stony Mountain gabbro has a sub-alkaline basaltic composition, variable TiO2, MgO and Ni/Cr values. The rocks have a geochemical signature typical of island-arcs; the degree of LREE enrichment, prominent negative Nb anomalies and Nb/Th ratios are all features of low-K to medium-K tholeiitic basalts in modern island-arc, subduction-related lavas. Isotope data are dominated by juvenile compositions that are consistent with derivation from lithospheric and asthenospheric sources during decompression melting of the mantle. The Stony Mountain gabbro records subduction zone magmatism in a rifted island arc setting and can be modeled as the product of ~ 10–15% hydrous partial melting of variable mixtures of MORB- and OIB-like mantle sources overprinted by a minor subducted-slab derived hydrous fluid component. By analogy with modern settings the rocks of the Stony Mountain gabbro are comparable to MORB-like to OIB-type enriched rocks from the Lau Island and Sumisu Rift and are interpreted to have formed within an evolving Early Paleozoic island arc–back arc rift–basin system. The presence of an Early Cambrian arc–back arc rift system in Carolinia is broadly coeval with arc–back arc volcanism in other peri-Gondwanan blocks of the Appalachians and may be related to the Early Paleozoic opening of the Rheic Ocean.}, number={2-3}, journal={GONDWANA RESEARCH}, author={Pollock, Jeffrey C. and Hibbard, James P.}, year={2010}, month={Mar}, pages={500–515} }
 @article{pollock_hibbard_sylvester_2009, title={Early Ordovician rifting of Avalonia and birth of the Rheic Ocean: U-Pb detrital zircon constraints from Newfoundland}, volume={166}, ISSN={["0016-7649"]}, DOI={10.1144/0016-76492008-088}, abstractNote={Abstract: Avalonia is the largest accreted crustal block in the Appalachian orogen and comprises a collection of late Neoproterozoic volcano-sedimentary sequences that are overlain by a Palaeozoic platformal sedimentary succession. Detrital zircons from the Conception Group are dominated by 570–620 Ma ages and contain a significant component generated by erosion of coeval igneous arc-volcanic rocks. Overlying samples from the Cuckold and Crown Hill formations are dominated by Neoproterozoic populations with ages between 600 and 650 Ma and are interpreted to be derived from the underlying calc-alkaline arc-plutonic rocks. Early Palaeozoic platform units are dominated by c. 620 Ma zircons with lesser Mesoproterozoic and Palaeoproterozoic zircons. The range of detrital zircon ages is inconsistent with a West African provenance and suggests that Avalonia originated along the Gondwanan margin of the Amazon craton. The influx of Mesoproterozoic and Palaeoproterozoic detritus in the Avalonian platform suggests a major change in tectonic regime. The prominent change in provenance is interpreted to be related to separation of Avalonia from Gondwana during the Early Ordovician opening of the Rheic Ocean. The Redmans Formation is interpreted to represent the rift–drift transition of the Rheic Ocean, which imposes important constraints on the palaeotectonic evolution of Avalonia. Supplementary material: U–Pb isotopic data of LA-ICP-MS analysis of detrital zircons are available at http://www.geolsoc.org.uk/SUP18346.}, journal={JOURNAL OF THE GEOLOGICAL SOCIETY}, author={Pollock, Jeffrey C. and Hibbard, James P. and Sylvester, Paul J.}, year={2009}, month={May}, pages={501–515} }
 @article{hibbard_pollock_brennan_samson_secor_2009, title={Significance of New Ediacaran Fossils and U-Pb Zircon Ages from the Albemarle Group, Carolina Terrane of North Carolina}, volume={117}, ISSN={["1537-5269"]}, DOI={10.1086/600863}, abstractNote={The Albemarle Group is one of the major defining stratigraphic units of the Carolina terrane, the best‐known division of the southern Appalachian peri‐Gondwanan block of Carolinia. As such, the group is a significant factor in the correlation of Carolinia with other peri‐Gondwanan blocks both in the Appalachians and globally. The traditionally held Ediacaran age of the group has been in question for more than a decade because of a report of Late Cambrian and younger fossils from two quarries in the group. The fossil report led to a major revision of the stratigraphy and structural reinterpretation of the Carolina terrane. Our recent studies have focused on the stratigraphy, paleontology, and geochronology of the Cid Formation in the vicinity of one of the reported Paleozoic fossil locales. Contrary to the structural reinterpretation of the Albemarle Group, Cid mudstone is shown to be in conformable and gradational contact with Flat Swamp felsic volcanics of the Cid Formation; we have obtained a precise U‐Pb zircon age of 
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 @misc{schulz_stewart_tucker_pollock_ayuso_2008, title={The Ellsworth terrane, coastal Maine: Geochronology, geochemistry, and Nd-Pb isotopic composition - Implications for the rifting of Ganderia}, volume={120}, number={9-10}, journal={Geological Society of America Bulletin}, author={Schulz, K. J. and Stewart, D. B. and Tucker, R. D. and Pollock, J. C. and Ayuso, R. A.}, year={2008}, pages={1134–1158} }
 @misc{pollock_wilton_van staal_morrissey_2007, title={U-Pb detrital zircon geochronological constraints on the Early Silurian collision of Ganderia and Laurentia along the Dog Bay Line: The terminal Iapetan suture in the Newfoundland Appalachians}, volume={307}, number={2}, journal={American Journal of Science}, author={Pollock, J. C. and Wilton, D. H. C. and Van Staal, C. R. and Morrissey, K. D.}, year={2007}, pages={399–433} }
 @article{rogers_staal_mcnicoll_pollock_zagorevski_whalen_2006, title={Neoproterozoic and Cambrian arc magmatism along the eastern margin of the Victoria Lake Supergroup: A remnant of Ganderian basement in central Newfoundland?}, volume={147}, ISSN={["1872-7433"]}, DOI={10.1016/j.precamres.2006.01.025}, abstractNote={The eastern margin of the composite and structurally complex Victoria Lake Supergroup has previously been mapped where the Silurian Rogerson Lake conglomeratic rocks unconformably overlie Cambrian Tally Pond volcanic rocks. However, the recognition that the form of this contact changes between an unconformity and a brittle-ductile fault, in conjunction with the Neoproterozoic age of the Crippleback Intrusive Suite, dictate that the above interpretation of the nature of this margin requires revision. These discrepancies are resolved by the recognition of a Neoproterozoic, largely bimodal volcanic sequence (Sandy Brook Group), which is unconformably overlain by Rogerson Lake rocks to the east, with these combined units in fault contact with the Tally Pond Group to the west. The Sandy Brook Group and Crippleback Intrusive Suite form a terrane of ca. 563 Ma rocks with continental arc-like geochemical signatures. The distinctly negative ɛNd,563 values for the felsic rocks (mean −3) of this terrane imply derivation from a crystalline basement older than the largely Pan-African crust that underlies contemporaneous volcanic rocks in West Avalonia, but similar to that inferred for the Gander Zone. Thus this terrane is likely to be the leading edge of the peri-Gondwanan microcontinent Ganderia. The ca. 511 Ma Tally Pond Group arc magmatism represent some of the oldest products of Iapetean subduction in Newfoundland. Although the Tally Pond Group are only observed to be in fault contact with the ca. 50 million year older Sandy Brook Group, the high proportion of felsic volcanic rocks, Sandy Brook/Crippleback age inherited zircons and Pb isotopic data all support the inference that the Tally Pond Group was formed on Sandy Brook/Crippleback continental crust.}, number={3-4}, journal={PRECAMBRIAN RESEARCH}, author={Rogers, N. and Staal, C. R. and McNicoll, V. and Pollock, J. and Zagorevski, A. and Whalen, J.}, year={2006}, month={Jul}, pages={320–341} }
 @article{pollock_2004, title={Geology of the Roman Catholic Basilica of St. John the Baptist, St. John's, Newfoundland}, volume={31}, number={1}, journal={Geoscience Canada}, author={Pollock, J.}, year={2004}, pages={10-} }