Taylor Frederick W Quinn Terrence Michael quinn@utig.ig.utexas.edu 0000-0003-0323-9175 Gallup Christina D Edwards R Lawrence edwar001@umn.edu 0000-0002-7027-5881 1994 (Table 1) Age determination of ODP Hole 134-831B dataset https://doi.org/10.1594/PANGAEA.787342 Taylor Frederick W Quinn Terrence Michael quinn@utig.ig.utexas.edu 0000-0003-0323-9175 Gallup Christina D Edwards R Lawrence edwar001@umn.edu 0000-0002-7027-5881 1994 Quaternary plate convergence rates at the New Hebrides Island Arc from the chronostratigraphy of Bougainville Guyot (Site 831) book chapter In: Green, HG; Collot, J-Y; Stokking, LB; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program) 134 https://doi.org/10.2973/odp.proc.sr.134.003.1994 47-57 We have determined convergence rates of the Australia plate with the New Hebrides Island Arc using the chronostratigraphy of Bougainville Guyot, drilled at Site 831, Ocean Drilling Program Leg 134. The convergence rate at the New Hebrides Island Arc is the vectorial sum of convergence rates between the Australia and Pacific plates (8.8 cm/yr at Espiritu Santo Island) and the opening rate of the North Fiji Basin. We assume that the relative motion of the Australia and Pacific plates is unchanging on the 1.5 m.y. time scale and that any changes of rate occurred in the North Fiji Basin. Convergence rates can be calculated because we know the distances at which carbonate sedimentation would cease and resume as the Bougainville Guyot emerged and submerged during its crossing of the outer rise flexure west of the New Hebrides Island Arc. From 1.42 to 0.393 Ma, Bougainville Guyot was subaerially exposed as it moved approximately 177 km across the outer rise and no sediment was deposited. The mean convergence rate during this time interval was 17.2 +/- 7 cm/yr, as determined from strontium-isotope and uranium-series ages of the last carbonates before emergence and the first carbonates deposited after submergence. The Australia plate has converged approximately 52 km with the New Hebrides Island Arc at a mean rate of 13.2 +/- 1 cm/yr since 0.393 +/- .011 Ma when Bougainville Guyot re-submerged and carbonate sedimentation resumed. This age is based on a precise mass-spectrometric 230Th age measurement and is reliable because the uranium isotopic composition of the sample indicates no diagenetic alteration. The change in convergence rates from 17.2 to 13.2 cm/yr indicates a significant change in the opening rate of the North Fiji Basin. However, this conclusion depends on the age of initial opening of the North Fiji Basin. If the North Fiji Basin began to open at 10 Ma, then the average opening rate at Espiritu Santo Island has been 6 cm/yr. If opening began at 12 Ma, then the average rate had to be 5 cm/yr. Because the relative motion between the Australia and Pacific plates is 8.8 cm/yr, the net convergence rate at the central New Hebrides Island Arc must have averaged 13.8 to 14.8 cm/yr. Younger dates of initial opening would require higher average convergence rates. If the convergence rate of 13.2 cm/yr at Espiritu Santo Island had prevailed for the entire opening of the North Fiji Basin, then the basin would have taken 13-14 m.y. to open at a mean rate of 4.4 cm/yr. This is contrary to hypotheses for the time of origin of the North Fiji Basin. 166.673 166.673 -16.009 -16.009 166.673 -16.009 1990-11-13T04:00:00 1990-11-20T16:30:00 112.0 323.52 vertical profile ODP Ocean Drilling Program https://www-odp.tamu.edu:443/ Ocean Drilling Program, Texas A&M University ODP http://www-odp.tamu.edu/ https://ror.org/01f5ytq51 134-831B -16.009 166.673 -1078.0 1990-11-13T04:00:00 1990-11-20T16:30:00 852 m 87.44 m Coral Sea Leg134 https://doi.org/10.2973/odp.proc.ir.134.1992 Collot, Jean-Yves Greene, H Gary 1990-10-11 1990-12-17 Joides Resolution https://www-odp.tamu.edu:443/resolutn.html Drilling/drill rig DRILL 83 cores; 749.6 m cored; 0 m drilled; 11.7 % recovery 45 CC-BY-3.0 Creative Commons Attribution 3.0 Unported https://creativecommons.org/licenses/by/3.0/ Sample code/label Sample label DSDP/ODP/IODP sample designation hdl:10013/epic.27914.d001 Taylor Frederick W Sample label (DSDP/ODP/IODP sample designation) DEPTH, sediment/rock Depth sed m depth http://purl.obolibrary.org/obo/PATO_0001595 sediment http://purl.obolibrary.org/obo/ENVO_00002007 rock Length L http://dbpedia.org/resource/Length mbsf Depth sed [m] (mbsf) δ234 Uranium δ234U ‰ Measured Taylor Frederick W δ234U [‰] (Measured) δ234 Uranium, standard deviation δ234U std dev ± standard deviation std dev https://en.wikipedia.org/wiki/Standard_deviation Measured Taylor Frederick W δ234U std dev [±] (Measured) Age, dated Age dated ka age http://purl.obolibrary.org/obo/PATO_0000011 Time T http://dbpedia.org/resource/Time Age, 230Thorium Taylor Frederick W Age dated [ka] (Age, 230Thorium) Age, dated, standard deviation Age dated std dev ± age http://purl.obolibrary.org/obo/PATO_0000011 standard deviation std dev https://en.wikipedia.org/wiki/Standard_deviation Age, 230Thorium Taylor Frederick W + Age dated std dev [±] (+, Age, 230Thorium) Age, dated, standard deviation Age dated std dev ± age http://purl.obolibrary.org/obo/PATO_0000011 standard deviation std dev https://en.wikipedia.org/wiki/Standard_deviation Age, 230Thorium Taylor Frederick W - Age dated std dev [±] (-, Age, 230Thorium) δ234 Uranium δ234U ‰ Calculated Taylor Frederick W Initial d234U is calculated from the measured d234U and 230Th age using the equation: Initial d234U = (Measured d234) (e**(lambda(234)T). The missing values in the first row indicates that initial d234U could not be calculated because the 230Th age equation in the column to the left could not be solved. δ234U [‰] (Initial d234U is calculated f...) δ234 Uranium, standard deviation δ234U std dev ± standard deviation std dev https://en.wikipedia.org/wiki/Standard_deviation Calculated Taylor Frederick W Initial δ234U std dev [±] (Initial, Calculated) Age, dated Age dated ka age http://purl.obolibrary.org/obo/PATO_0000011 Time T http://dbpedia.org/resource/Time Age, 234U/238U Uranium-Uranium Taylor Frederick W Age dated [ka] (Age, 234U/238U Uranium-Uranium) Age, dated, standard deviation Age dated std dev ± age http://purl.obolibrary.org/obo/PATO_0000011 standard deviation std dev https://en.wikipedia.org/wiki/Standard_deviation Age, 234U/238U Uranium-Uranium Taylor Frederick W Age dated std dev [±] (Age, 234U/238U Uranium-Uranium) supplement citable author23862 author29376 author31952 author42352 basis5 campaign106 event31214 geocode1 geocode1599 geocode1600 geocode1601 geocode8128 inst34 license101 method10974 method420 method50 method5059 method6813 method7797 param27400 param27401 param5506 param6165 param790 pi31952 project3 ref36900 term1073131 term1073135 term20610 term37764 term38263 term41056 term43863 term43975 topotype3