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Статті в журналах з теми "Newer Volcanic Province"

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Автор: Grafiati

Опубліковано: 10 грудня 2022

Оновлено: 28 січня 2023

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1

Gray, C. M., and I. McDougall. "K-Ar geochronology of basalt petrogenesis, Newer Volcanic Province, Victoria." Australian Journal of Earth Sciences 56, no. 2 (March 2009): 245–58. http://dx.doi.org/10.1080/08120090802547066.

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2

Cas, R. A. F., J. van Otterloo, T. N. Blaikie, and J. van den Hove. "The dynamics of a very large intra-plate continental basaltic volcanic province, the Newer Volcanics Province, SE Australia, and implications for other provinces." Geological Society, London, Special Publications 446, no. 1 (November 7, 2016): 123–72. http://dx.doi.org/10.1144/sp446.8.

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3

Ismail, Rafika, David Phillips, and William D. Birch. "40Ar/39Ar dating of alkali feldspar megacrysts from selected young volcanoes of the Newer Volcanic Province, Victoria." Proceedings of the Royal Society of Victoria 125, no. 2 (2013): 59. http://dx.doi.org/10.1071/rs13019.

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The Newer Volcanic Province (NVP) in Victoria, with extension into south-eastern South Australia, represents the youngest chapter of Cenozoic volcanism in south-eastern Australia. However, most ages have been determined by the potassium–argon (K–Ar) method, and the age data are not comprehensive. In addition, few ages exist for the array of scoria cone volcanoes in the NVP. Seven alkali feldspar samples, mostly anorthoclase megacrysts, from volcanic centres in the NVP were used for 40Ar/39Ar dating in the present study. In geochronological order, with ages quoting 95% confidence limits, locations are Mount Franklin near Daylesford (0.110 ± 0.014 Ma), Red Rock near Alvie (0.116 ± 0.048 Ma), Lake Bullenmerri at Camperdown (0.116 ± 0.019 Ma), Ridge Road Quarry near Daylesford (2.01 ± 0.11 Ma) and Mount Kororoit near Diggers Rest (3.74 ± 0.26 Ma). Two samples from The Anakies, near Bacchus Marsh, produced discordant results suggesting a maximum age of ca. 1.9 Ma. The analyses and reported ages in the present study not only provide new geochronological data for the province, but also elucidate the difficulties in dating very young basalts using the 40Ar/39Ar dating method. These results are consistent with the erosion levels of the scoria volcanoes sampled, and indicate a major episode of explosive volcanic activity at ca. 100 ka. In contrast, the more eroded Mount Kororoit is considered to be ca. 3.7 Ma in age. The age of The Anakies is more equivocal owing to the indicated presence of excess argon and a maximum age of ca. 1.9 Ma is suggested for this locality. Given the latter results and lack of precision obtainable from the younger samples, the possibility remains that other samples contained extraneous argon and that the ages generated are thus maximum eruption ages. Analyses of additional samples from these and other localities will be required to further resolve this issue.

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4

Aivazpourporgou, Sahereh, Stephan Thiel, Patrick Hayman, Louis Moresi, and Graham Heinson. "Results from long-period MT array in the Newer Volcanic Province, Western Victoria, Australia." ASEG Extended Abstracts 2013, no. 1 (December 2013): 1–3. http://dx.doi.org/10.1071/aseg2013ab370.

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5

Vogel, Derek C., and Reid R. Keays. "The petrogenesis and platinum-group element geochemistry of the Newer Volcanic Province, Victoria, Australia." Chemical Geology 136, no. 3-4 (April 1997): 181–204. http://dx.doi.org/10.1016/s0009-2541(96)00142-8.

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6

Graeber, Frank M., Gregory A. Houseman, and Stewart A. Greenhalgh. "Regional teleseismic tomography of the western Lachlan Orogen and the Newer Volcanic Province, southeast Australia." Geophysical Journal International 149, no. 2 (May 2002): 249–66. http://dx.doi.org/10.1046/j.1365-246x.2002.01598.x.

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7

Phillips, David. "40Ar/39Ar geochronology of feldspar megacrysts from Late Pleistocene volcanoes, Newer Volcanic Province, southeast Australia." Quaternary International 279-280 (November 2012): 379–80. http://dx.doi.org/10.1016/j.quaint.2012.08.1176.

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8

Blaikie, T. N., L. Ailleres, P. G. Betts, and R. A. F. Cas. "Interpreting subsurface volcanic structures using geologically constrained 3-D gravity inversions: Examples of maar-diatremes, Newer Volcanics Province, southeastern Australia." Journal of Geophysical Research: Solid Earth 119, no. 4 (April 2014): 3857–78. http://dx.doi.org/10.1002/2013jb010751.

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9

Oostingh, K. F., F. Jourdan, E. L. Matchan, and D. Phillips. "40Ar/39Ar geochronology reveals rapid change from plume-assisted to stress-dependent volcanism in the Newer Volcanic Province, SE Australia." Geochemistry, Geophysics, Geosystems 18, no. 3 (March 2017): 1065–89. http://dx.doi.org/10.1002/2016gc006601.

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10

Van Otterloo, J., M. Raveggi, R. A. F. Cas, and R. Maas. "Polymagmatic Activity at the Monogenetic Mt Gambier Volcanic Complex in the Newer Volcanics Province, SE Australia: New Insights into the Occurrence of Intraplate Volcanic Activity in Australia." Journal of Petrology 55, no. 7 (June 13, 2014): 1317–51. http://dx.doi.org/10.1093/petrology/egu026.

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11

Gillen, D., M. Honda, A. R. Chivas, I. Yatsevich, D. B. Patterson, and P. F. Carr. "Cosmogenic 21Ne exposure dating of young basaltic lava flows from the Newer Volcanic Province, western Victoria, Australia." Quaternary Geochronology 5, no. 1 (February 2010): 1–9. http://dx.doi.org/10.1016/j.quageo.2009.08.004.

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12

Price, R. C., C. M. Gray, and F. A. Frey. "Strontium isotopic and trace element heterogeneity in the plains basalts of the Newer Volcanic Province, Victoria, Australia." Geochimica et Cosmochimica Acta 61, no. 1 (January 1997): 171–92. http://dx.doi.org/10.1016/s0016-7037(96)00318-3.

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13

Demidjuk, Zoe, Simon Turner, Mike Sandiford, Rhiannon George, John Foden, and Mike Etheridge. "U-series isotope and geodynamic constraints on mantle melting processes beneath the Newer Volcanic Province in South Australia." Earth and Planetary Science Letters 261, no. 3-4 (September 2007): 517–33. http://dx.doi.org/10.1016/j.epsl.2007.07.006.

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14

Matchan, E. L., E. B. Joyce, and D. Phillips. "A new 40Ar/39Ar eruption age for the Mount Widderin volcano, Newer Volcanic Province, Australia, with implications for eruption frequency in the region." Australian Journal of Earth Sciences 63, no. 2 (February 17, 2016): 175–86. http://dx.doi.org/10.1080/08120099.2016.1156576.

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15

Matchan, E., and D. Phillips. "New 40Ar/39Ar ages for selected young (<1 Ma) basalt flows of the Newer Volcanic Province, southeastern Australia." Quaternary Geochronology 6, no. 3-4 (June 2011): 356–68. http://dx.doi.org/10.1016/j.quageo.2011.03.002.

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16

Matchan, Erin L., David Phillips, Fred Jourdan, and Korien Oostingh. "Early human occupation of southeastern Australia: New insights from 40Ar/39Ar dating of young volcanoes." Geology 48, no. 4 (February 6, 2020): 390–94. http://dx.doi.org/10.1130/g47166.1.

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Анотація:

Abstract In Australia, the onset of human occupation (≥65 ka?) and dispersion across the continent are the subjects of intense debate and are critical to understanding global human migration routes. New-generation multi-collector mass spectrometers capable of high-precision 40Ar/39Ar dating of young (<500 ka) samples provide unprecedented opportunities to improve temporal constraints of archaeological events. In southeastern Australia, a novel approach to improving understanding of occupation involves dating key volcanic eruptions in the region, referenced to stone artifacts and Aboriginal oral traditions. The current study focuses on two monogenetic volcanoes in the Newer Volcanic Province of southeastern Australia: Budj Bim (previously Mount Eccles) and Tower Hill. Budj Bim and its surrounding lava landforms are of great cultural significance and feature prominently in the oral traditions of the Gunditjmara people. Tower Hill is of archaeological significance due to the occurrence of a stone tool beneath tephra. 40Ar/39Ar eruption ages of 36.9 ± 3.1 ka (95% confidence interval) and 36.8 ± 3.8 ka (2σ) were determined for the Budj Bim and Tower Hill volcanic complexes, respectively. The Tower Hill eruption age is a minimum age constraint for human presence in Victoria, consistent with published optically stimulated luminescence and 14C age constraints for the earliest known occupation sites in Tasmania, New South Wales, and South Australia. If aspects of oral traditions pertaining to Budj Bim or its surrounding lava landforms reflect volcanic activity, this could be interpreted as evidence for these being some of the oldest oral traditions in existence.

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17

Matchan, E. L., D. Phillips, E. Traine, and D. Zhu. "Major element data, 40Ar/39Ar step-heating and step-crushing data for anorthoclase megacrysts from the Newer Volcanic Province, south-eastern Australia." Data in Brief 19 (August 2018): 1847–51. http://dx.doi.org/10.1016/j.dib.2018.06.080.

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18

Ba, Kailun, Stephen S. Gao, Kelly H. Liu, Fansheng Kong, and Jianguo Song. "Receiver function imaging of the 410 and 660 km discontinuities beneath the Australian continent." Geophysical Journal International 220, no. 3 (November 20, 2019): 1481–90. http://dx.doi.org/10.1093/gji/ggz525.

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SUMMARY To provide constraints on a number of significant controversial issues related to the structure and dynamics of the Australian continent, we utilize P-to-S receiver functions (RFs) recorded by 182 stations to map the 410 and 660 km discontinuities (d410 and d660, respectively) bordering the mantle transition zone (MTZ). The RFs are stacked in successive circular bins with a radius of 1° under a non-plane wave front assumption. The d410 and d660 depths obtained using the 1-D IASP91 earth model show a systematic apparent uplifting of about 15 km for both discontinuities in central and western Australia relative to eastern Australia, as the result of higher seismic wave speeds in the upper mantle beneath the former area. After correcting the apparent depths using the Australian Seismological Reference Model, the d410 depths beneath the West Australia Craton are depressed by ∼10 km on average relative to the normal depth of 410 km, indicating a positive thermal anomaly of 100 K at the top of the MTZ which could represent a transition from a thinner than normal MTZ beneath the Indian ocean and the normal MTZ beneath central Australia. The abnormally thick MTZ beneath eastern Australia can be adequately explained by subducted cold slabs in the MTZ. A localized normal thickness of the MTZ beneath the Newer Volcanics Province provides supporting evidence of non-mantle-plume mechanism for intraplate volcanic activities in the Australian continent.

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19

Heath, M., D. Phillips, and E. L. Matchan. "Basalt lava flows of the intraplate Newer Volcanic Province in south-east Australia (Melbourne region): 40Ar/39Ar geochronology reveals ~8 Ma of episodic activity." Journal of Volcanology and Geothermal Research 389 (January 2020): 106730. http://dx.doi.org/10.1016/j.jvolgeores.2019.106730.

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20

Murray-Wallace, Colin V. "Comment on: “New 40Ar/39Ar ages for selected young (<1 Ma) basalt flows of the Newer Volcanic Province, southeastern Australia” by E. Matchan & D. Phillips." Quaternary Geochronology 6, no. 6 (December 2011): 598–99. http://dx.doi.org/10.1016/j.quageo.2011.07.001.

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21

Matchan, Erin, and David Phillips. "Reply to Murray-Wallace, C.V. Comment on Matchan and Phillips, 2011. New 40Ar/39Ar ages for selected young (<1 Ma) basalt flows of the Newer Volcanic Province, southeastern Australia." Quaternary Geochronology 6, no. 6 (December 2011): 600. http://dx.doi.org/10.1016/j.quageo.2011.08.005.

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22

Wilkie, Benjamin, Fred Cahir, and Ian D. Clark. "Volcanism in Aboriginal Australian oral traditions: Ethnographic evidence from the Newer Volcanics Province." Journal of Volcanology and Geothermal Research 403 (October 2020): 106999. http://dx.doi.org/10.1016/j.jvolgeores.2020.106999.

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23

Boyce, J., I. Nicholls, R. Keays, and P. Hayman. "Victoria erupts: the Newer Volcanics Province of south-eastern Australia." Geology Today 30, no. 3 (May 2014): 105–9. http://dx.doi.org/10.1111/gto.12054.

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24

Jiang, Chengxin, Yingjie Yang, Nicholas Rawlinson, and William L. Griffin. "Crustal structure of the Newer Volcanics Province, SE Australia, from ambient noise tomography." Tectonophysics 683 (June 2016): 382–92. http://dx.doi.org/10.1016/j.tecto.2016.06.033.

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25

van den Hove, Jackson C., Laurent Ailleres, Peter G. Betts, and Ray A. F. Cas. "Subsurface structure of a large basaltic maar volcano examined using geologically constrained potential field modelling, Lake Purrumbete Maar, Newer Volcanics Province, southeastern Australia." Journal of Volcanology and Geothermal Research 304 (October 2015): 142–59. http://dx.doi.org/10.1016/j.jvolgeores.2015.08.020.

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26

Boyce, J. "The Newer Volcanics Province of southeastern Australia: a new classification scheme and distribution map for eruption centres." Australian Journal of Earth Sciences 60, no. 4 (June 2013): 449–62. http://dx.doi.org/10.1080/08120099.2013.806954.

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27

Hare, AG, and RAF Cas. "Volcanology and evolution of the Werribee Plains intraplate, basaltic lava flow-field, Newer Volcanics Province, southeast Australia." Australian Journal of Earth Sciences 52, no. 1 (February 2005): 59–78. http://dx.doi.org/10.1080/08120090500100051.

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28

Blaikie, T. N., L. Ailleres, P. G. Betts, and R. A. F. Cas. "A geophysical comparison of the diatremes of simple and complex maar volcanoes, Newer Volcanics Province, south-eastern Australia." Journal of Volcanology and Geothermal Research 276 (April 2014): 64–81. http://dx.doi.org/10.1016/j.jvolgeores.2014.03.001.

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29

Molin, Gianmario, and Marilena Stimpfl. "Crystal chemistry and intracrystalline relationships of orthopyroxene in a suite of high pressure ultramafic nodules from the ‘Newer Volcanics’ of Victoria, Australia." Mineralogical Magazine 58, no. 391 (June 1994): 325–32. http://dx.doi.org/10.1180/minmag.1994.058.391.15.

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AbstractA suite of orthopyroxenes from spinel Iherzolite xenoliths associated with basanites occurring in the Victorian (Australia) post-Pliocene ‘Newer Volcanics’ province was investigated by means of a crystal chemical methodology which provides accurate site occupancy and site configuration parameters.The M1 configuration is essentially constrained by AlVI rather than Fe2+. In addition, Fe3+, Cr3+ and Ti4+ are confined to M1 (Molin, 1989) and AlIV to TB. M2 is controlled by FeM22+ ⇌ MgM2, constrained by (Fe2+ + Ca)M2 > 0.14 atoms per formula unit (p.f.u.). Cation substitution in TB and M2 constrains the sum of the volumes of the respective polyhedra VTB+VM2 to remain essentially constant. Therefore, M2 favours the retention of the large Fe2+ up to melting-point, causing non-ideality of this iron-depleted orthopyroxene. As a consequence, the investigated orthopyroxene can be considered an ultimate Fe2+ carrier during partial mantle melting.

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30

Blaikie, Teagan, Laurent Ailleres, Peter Betts, and Ray Cas. "Three-dimensional potential field modelling of the subsurface morphology of complex maar volcanoes - Examples from the Newer Volcanics Province, Western Victoria." ASEG Extended Abstracts 2013, no. 1 (December 2013): 1–4. http://dx.doi.org/10.1071/aseg2013ab136.

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31

McBRIDE, J. S., D. D. LAMBERT, I. A. NICHOLLS, and R. C. PRICE. "Osmium Isotopic Evidence for Crust–Mantle Interaction in the Genesis of Continental Intraplate Basalts from the Newer Volcanics Province, Southeastern Australia." Journal of Petrology 42, no. 6 (June 2001): 1197–218. http://dx.doi.org/10.1093/petrology/42.6.1197.

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32

Blaikie, Teagan N., Laurent Ailleres, Ray A. F. Cas, and Peter G. Betts. "Three-dimensional potential field modelling of a multi-vent maar-diatreme — The Lake Coragulac maar, Newer Volcanics Province, south‐eastern Australia." Journal of Volcanology and Geothermal Research 235-236 (August 2012): 70–83. http://dx.doi.org/10.1016/j.jvolgeores.2012.05.002.

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33

Hare, AG, RAF Cas, R. Musgrave, and D. Phillips. "Magnetic and chemical stratigraphy for the Werribee Plains basaltic lava flow-field, Newer Volcanics Province, southeast Australia: implications for eruption frequency." Australian Journal of Earth Sciences 52, no. 1 (February 2005): 41–57. http://dx.doi.org/10.1080/08120090500100069.

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34

Blaikie, Teagan, Laurent Ailleres, Peter Betts, and Ray Cas. "Geophysical and volcanological insights into the subsurface morphology and eruptive histories of complex maar volcanoes within the Newer Volcanics Province, Western Victoria." ASEG Extended Abstracts 2013, no. 1 (December 2013): 1–3. http://dx.doi.org/10.1071/aseg2013ab138.

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35

Boyce, J. A., R. R. Keays, I. A. Nicholls, and P. Hayman. "Eruption centres of the Hamilton area of the Newer Volcanics Province, Victoria, Australia: pinpointing volcanoes from a multifaceted approach to landform mapping." Australian Journal of Earth Sciences 61, no. 5 (June 16, 2014): 735–54. http://dx.doi.org/10.1080/08120099.2014.923508.

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36

Watkins, Conor M., and J. David Rogers. "A New Look at Landslides of the Vermilion and Echo Cliffs, Northern Arizona." Environmental & Engineering Geoscience 28, no. 2 (April 22, 2022): 173–92. http://dx.doi.org/10.2113/eeg-d-21-00063.

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ABSTRACT The Vermilion and Echo Cliffs form a nearly continuous escarpment more than 160 km long within the Colorado Plateau physiographic province of North America. The cliffs overlie the Marble Platform in northern Arizona and are located along the Colorado River, just upstream of the Grand Canyon. Large rotational block landslides mantle the erosional escarpment along most of its extent. Although these landslides have been noted for over 100 years, their likely origin has never been explained. Landslide failure surfaces appear to be influenced by the Petrified Forest Member of the Triassic Chinle Formation, a shale layer containing smectite clay weathered from volcanic ash. Although landslides are common along the majority of escarpments comprising the Colorado Plateau where the Petrified Forest Member and other shales outcrop, most appear to have been inactive since the early Holocene. Multiple generations of landslides and remnants of previous slides exist up to 3 km from the present cliff face. Multiple working hypotheses explaining these landslides are explored in this article, including past landslides and/or lava dams along the Colorado River within the Grand Canyon, periods of wetter climate with higher groundwater levels, and earthquakes related to nearby faulting and volcanism. Various sliding modes along these cliffs are described along with potential triggering mechanisms. Back-analysis of these landslides has been conducted using mechanical properties of the formations involved as well as varying groundwater levels. Calculated factors of safety for existing slides under present conditions are greater than unity, consistent with their apparent stability.

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37

Matthews, Chris, Graeme Beardsmore, Jim Driscoll, and Nicky Pollington. "Heat flow data from the southeast of South Australia: distribution and implications for the relationship between current heat flow and the Newer Volcanics Province." Exploration Geophysics 44, no. 2 (June 2013): 133–44. http://dx.doi.org/10.1071/eg12052.

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38

Blaikie, T. N., J. van Otterloo, L. Ailleres, P. G. Betts, and R. A. F. Cas. "The erupted volumes of tephra from maar volcanoes and estimates of their VEI magnitude: Examples from the late Cenozoic Newer Volcanics Province, south-eastern Australia." Journal of Volcanology and Geothermal Research 301 (August 2015): 81–89. http://dx.doi.org/10.1016/j.jvolgeores.2015.05.004.

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39

Sun, Yi, Axel K. Schmitt, Lucia Pappalardo, and Massimo Russo. "Quantification of excess 231Pa in late Quaternary igneous baddeleyite." American Mineralogist 105, no. 12 (December 1, 2020): 1830–40. http://dx.doi.org/10.2138/am-2020-7449.

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Abstract Initial excess protactinium (231Pa) is a frequently suspected source of discordance in baddeleyite (ZrO2) geochronology, which limits accurate U/Pb dating, but such excesses have never been directly demonstrated. In this study, Pa incorporation in late Holocene baddeleyite from Somma-Vesuvius (Campanian Volcanic Province, central Italy) and Laacher See (East Eifel Volcanic Field, western Germany) was quantified by U-Th-Pa measurements using a large-geometry ion microprobe. Baddeleyite crystals isolated from subvolcanic syenites have average U concentrations of ~200 ppm and are largely stoichiometric with minor abundances of Nb, Hf, Ti, and Fe up to a few weight percent. Measured (231Pa)/(235U) activity ratios are significantly above the secular equilibrium value of unity and range from 3.4(8) to 14.9(2.6) in Vesuvius baddeleyite and from 3.6(9) to 8.9(1.4) in Laacher See baddeleyite (values within parentheses represent uncertainties in the last significant figures reported as 1σ throughout the text). Crystallization ages of 5.12(56) ka (Vesuvius; MSWD = 0.96, n = 12) and 15.6(2.0) ka (Laacher See; MSWD = 0.91, n = 10) were obtained from (230Th)/(238U) disequilibria for the same crystals, which are close to the respective eruption ages. Applying a corresponding age correction indicates average initial (231Pa)/(235U)0 of 8.8(1.0) (Vesuvius) and 7.9(5) (Laacher See). For reasonable melt activities, model baddeleyite-melt distribution coefficients of DPa/DU = 5.8(2) and 4.1(2) are obtained for Vesuvius and Laacher See, respectively. Speciation-dependent (Pa4+ vs. Pa5+) partitioning coefficients (D values) from crystal lattice strain models for tetra- and pentavalent proxy ions significantly exceed DPa/DU inferred from direct analysis of 231Pa for Pa5+. This is consistent with predominantly reduced Pa4+ in the melt, for which D values similar to U4+ are expected. Contrary to common assumptions, baddeleyite-crystallizing melts from Vesuvius and Laacher See appear to be dominated by Pa4+ rather than Pa5+. An initial disequilibrium correction for baddeleyite geochronology using DPa/DU = 5 ± 1 is recommended for oxidized phonolitic melt compositions.

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40

Heads, Michael. "Metapopulation vicariance in the Pacific genus Coprosma (Rubiaceae) and its Gondwanan relatives." Australian Systematic Botany 30, no. 6 (2017): 422. http://dx.doi.org/10.1071/sb16047.

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Coprosma is perhaps the most ubiquitous plant genus in New Zealand. It belongs to the tribe Anthospermeae, which is distinctive in the family Rubiaceae through its small, simple, wind-pollinated flowers and its southern hemisphere distribution. The tribe comprises four main clades found respectively in South Africa, Africa, Australia and the Pacific. The high level of allopatry among the four subtribes is attributed here to their origin by vicariance. The Pacific clade, subtribe Coprosminae, is widespread around the margins of the South Pacific and also occurs on most of the high islands. Distributions of the main clades in the subtribe are mapped here and are shown to be repeated in other groups. The distribution patterns also coincide with features of regional geology. Large-scale volcanism has persisted in the central Pacific region since at least the Jurassic. At that time, the oldest of the Pacific large igneous provinces, the Shatsky Rise, began to be erupted in the region now occupied by French Polynesia. Large-scale volcanism in the central Pacific continued through the Cretaceous and the Cenozoic. The sustained volcanism, along with details of the clade distributions, both suggest that the Coprosminae have persisted in the central Pacific by survival of metapopulations on individually ephemeral islands. It is also likely that vicariance of metapopulations has taken place, mediated by processes such as the subsidence of the Pacific seafloor by thousands of metres, and rifting of active arcs by transform faults. It is sometimes argued that a vicariance origin is unlikely for groups on young, oceanic islands that have never been connected by continuous land, but metapopulation vicariance does not require physical contact between islands.

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Faure, Eric. "Did the Justinianic Plague Truly Reach Frankish Europe around 543 AD?" Vox Patrum 78 (June 15, 2021): 427–66. http://dx.doi.org/10.31743/vp.12278.

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This article focuses on the episodes of bubonic plague recorded around 543 AD in Frankish Europe which on re-reading appear doubtful. Beginning in 541 and for two centuries, the Justinianic plague ravaged the Mediterranean area over several successive waves. The first mentions concern Egypt; the plague then spreads northward to Constantinople and almost concomitantly or shortly afterward moves westward until it reaches Western Europe. For this last region, the main source is Bishop Gregory of Tours, who in both his historical and his hagiographic writings, provides numerous data on the first outbreaks that raged in Frankish Europe, episodes to which he was a contemporary (even if for the first, he was still in early childhood). According to Gregory, around 543, bubonic plague ravaged several areas under Frankish rule. However, among others, intertextual, contextualized and chronological analyses strongly suggest that these events were in fact fictional. Gregory seems to have wanted to balance during epidemics of plague, the behavior of two bishops of Clermont that were totally opposed. In the episode of 571, when plague struck the episcopal city, the unworthy Bishop Cautinus, to escape disease, had fled the city in cowardice. In the other episode, through the intercession of Gregory's paternal uncle, the virtuous Gallus, the immediate predecessor of Cautinus and that of a saint specific of the paternal branch, the city, including the diocese, was spared from the plague. Other references to similar events in which, through saints, the plague is driven out, or territories are protected from it are also dated arbitrarily from this period. Furthermore, unlike the episode of 571, the plague of 543 is never considered a punishment for sin; moreover, no miraculous healing of plague patients is recorded. Contemporary texts from other authors of Frankish Europe, although they are rare, do not mention any epidemic around 543 - especially the Vita of Caesarius of Arles, written shortly after the death of this bishop (from 542 to 547-9) by several hagiographers - while two of Gregory’s texts, which are repeated almost verbatim, indicate that the province of Arles was the region most affected. This fact underscores the decisive contribution that hagiographic texts can make in the analysis of facts considered to be historical. Finally, the dramatic deteriorations in the health situation described in Gregory’s reports could have a background of truth and be the consequence of the climatic cooling observed from 536, likely due to volcanic eruptions, but did not involve the bubonic plague.

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"Pictorial : Products of Phreatomagmatic Activity in the Newer Volcanic Province, Southeastern Australia." Journal of Geography (Chigaku Zasshi) 105, no. 4 (1996): Plate3—Plate4. http://dx.doi.org/10.5026/jgeography.105.4_plate3.

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Lesti, C., G. Giordano, F. Salvini, and R. Cas. "Volcano tectonic setting of the intraplate, Pliocene-Holocene, Newer Volcanic Province (southeast Australia): Role of crustal fracture zones." Journal of Geophysical Research 113, B7 (July 30, 2008). http://dx.doi.org/10.1029/2007jb005110.

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44

Boyce, Julie A., Ian A. Nicholls, Reid R. Keays, and Patrick C. Hayman. "Variation in parental magmas of Mt Rouse, a complex polymagmatic monogenetic volcano in the basaltic intraplate Newer Volcanics Province, southeast Australia." Contributions to Mineralogy and Petrology 169, no. 2 (January 30, 2015). http://dx.doi.org/10.1007/s00410-015-1106-y.

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45

Jordan, S. C., S. M. Jowitt, and R. A. F. Cas. "Origin of temporal - compositional variations during the eruption of Lake Purrumbete Maar, Newer Volcanics Province, southeastern Australia." Bulletin of Volcanology 77, no. 1 (December 5, 2014). http://dx.doi.org/10.1007/s00445-014-0883-x.

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Hoover, William F., F. Zeb Page, Daniel J. Schulze, Kouki Kitajima, and John W. Valley. "Massive Fluid Influx beneath the Colorado Plateau (USA) Related to Slab Removal and Diatreme Emplacement: Evidence from Oxygen Isotope Zoning in Eclogite Xenoliths." Journal of Petrology, November 5, 2020. http://dx.doi.org/10.1093/petrology/egaa102.

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Abstract The Colorado Plateau has undergone as much as 1·8 km of uplift over the past 80 Myr, but never underwent the pervasive deformation common in the neighboring tectonic provinces of the western USA. To understand the source, timing and distribution of mantle hydration, and its role in plateau uplift, garnets from four eclogite xenoliths of the Moses Rock diatreme (Navajo Volcanic Field, Utah, USA) were analyzed in situ for δ18O by secondary ion mass spectrometry. These garnets have the largest reported intra-crystalline oxygen isotope zoning to date in mantle-derived xenoliths with core-to-rim variations of as much as 3 ‰. All samples have core δ18O values greater than that of the pristine mantle (∼5·3 ‰, mantle garnet as derived from mantle zircon in earlier work) consistent with an altered upper oceanic crust protolith. Oxygen isotope ratios decrease from core to rim, recording interaction with a low-δ18O fluid at high temperature, probably derived from serpentinite in the foundering Farallon slab. All zoned samples converge at a δ18O value of ∼6 ‰, regardless of core composition, suggesting that fluid infiltration was widely distributed. Constraints on the timing of this fluid influx, relative to diatreme emplacement, can be gained from diffusion modeling of major element zoning in garnet. Modeling using best estimates of peak metamorphic conditions (620 °C, 3·7 GPa) yields durations of <200 kyr, suggesting that fluid influx and diatreme emplacement were temporally linked. These eclogite xenoliths from the Colorado Plateau record extensive fluid influx, pointing to complex hydration–dehydration processes related to flat-slab subduction and foundering of the Farallon plate. Extensive hydration of the lithospheric mantle during this fluid influx may have contributed to buoyancy-driven uplift of the Colorado Plateau and melt-free emplacement of Navajo Volcanic Field diatremes.

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