Correlation of ignimbrites in the central Anatolian volcanic province using zircon and plagioclase ages and zircon compositions

Abstract Episodes of high eruptive fluxes (> 10 − 3  km 3 /year) in continental environments are associated with magmatism related to subduction, post-orogenic collapse, intra-plate hot spots, or rifting. During such episodes, voluminous ignimbrite deposits are produced which cover landscapes over 10 4 –10 5  km 2 . In such sequences, brief eruptive recurrence and chemical similarity limit the applicability of geochronological and geochemical correlation methods. Here, we present complementary geochronological data ( 40 Ar/ 39 Ar plagioclase eruption and 206 Pb/ 238 U zircon crystallization ages) for ignimbrites from the Miocene–Holocene Central Anatolian Volcanic Province (CAVP). In addition, we successfully employed zircon geochemistry (trace elements, oxygen isotopes) as an alteration-resistant indicator to correlate rhyodacitic to rhyolitic ignimbrites whose eruption age differences are too brief to be resolved by 40 Ar/ 39 Ar geochronology. By applying this method, we dismiss previous correlations between stratigraphic members (i.e., Sofular and Gordeles, Sofular and Sarimadentepe), but demonstrate close relationships for other CAVP ignimbrites (i.e., Kavak units 1 to 4; Cemilkoy ignimbrite and overlying fallout deposits). Our chronostratigraphy reveals two previously unrecognized eruptive pulses at ~ 9–8 Ma and 7–5 Ma which are characterized by increasing magmatic temperatures (~ 75–100 °C within each cycle). Despite a long-term (10 Ma) eruptive productivity that is about one order of magnitude smaller than in other magmatically active continental plateaus, the CAVP achieved high eruptive fluxes during brief (1–2 Ma) intervals.

[1]  G. Mahood,et al.  Correlation of ash-flow tuffs. , 1985 .

[2]  L. Ferrari,et al.  Ignimbrite flare‐up and deformation in the southern Sierra Madre Occidental, western Mexico: Implications for the late subduction history of the Farallon plate , 2002 .

[3]  F. Bea,et al.  Tracking magmatic processes through Zr/Hf ratios in rocks and Hf and Ti zoning in zircons: An example from the Spirit Mountain batholith, Nevada , 2006, Mineralogical Magazine.

[4]  A. Zanchi,et al.  Continental arc volcanism and tectonic setting in Central Anatolia, Turkey , 1988 .

[5]  R. Schumacher,et al.  The Kizilkaya ignimbrite — an unusual low-aspect-ratio ignimbrite from Cappadocia, central Turkey , 1996 .

[6]  R. Duncan,et al.  High‐resolution 40Ar/39Ar dating of the oldest oceanic basement basalts in the western Pacific basin , 2003 .

[7]  Y. Dilek,et al.  Seismic structure, crustal architecture and tectonic evolution of the Anatolian-African Plate Boundary and the Cenozoic Orogenic Belts in the Eastern Mediterranean Region , 2009 .

[8]  A. Schmitt,et al.  Buried rhyolites within the active, high-temperature Salton Sea geothermal system , 2008 .

[9]  E. Watson,et al.  New thermodynamic models and revised calibrations for the Ti-in-zircon and Zr-in-rutile thermometers , 2007 .

[10]  Lionel Wilson,et al.  Explosive volcanic eruptions — IV. The control of magma properties and conduit geometry on eruption column behaviour , 1980 .

[11]  C. Annen.  From plutons to magma chambers: Thermal constraints on the accumulation of eruptible silicic magma in the upper crust , 2009 .

[12]  E. Aydar,et al.  The geology of Mount Hasan stratovolcano, central Anatolia, Turkey , 1998 .

[13]  Richard E. Ernst,et al.  Revised definition of Large Igneous Provinces (LIPs) , 2008 .

[14]  T. M. Harrison,et al.  Zircon saturation revisited: temperature and composition effects in a variety of crustal magma types , 1983 .

[15]  William D. Gosnold,et al.  Episodic construction of batholiths: Insights from the spatiotemporal development of an ignimbrite flare-up , 2007 .

[16]  E. Watson,et al.  Kinetics of zircon dissolution and zirconium diffusion in granitic melts of variable water content , 1983 .

[17]  T. Ui,et al.  Geochemical features of collision-related volcanic rocks in central and eastern Anatolia, Turkey , 1995 .

[18]  J. Chorowicz,et al.  Hidden calderas evidenced by multisource geophysical data; example of Cappadocian Calderas, Central Anatolia , 1998 .

[19]  Jean-Luc Froger,et al.  Neogene ignimbrites of the Nevsehir plateau (Central Turkey): stratigraphy, distribution and source constraints , 1994 .

[20]  F. Innocenti,et al.  The Neogene calcalkaline volcanism of Central Anatolia: geochronological data on Kayseri—Nigde area , 1975, Geological Magazine.

[21]  H. Schmincke,et al.  Internal structure and occurrence of accretionary lapilli — a case study at Laacher See Volcano , 1991 .

[22]  P. Shane.  Correlation of rhyolitic pyroclastic eruptive units from the Taupo volcanic zone by Fe–Ti oxide compositional data , 1998 .

[23]  R. Schumacher,et al.  The pre-ignimbrite (phreato) plinian and phreatomagmatic phases of the Akdag-Zelve ignimbrite eruption in Central Anatolia, Turkey , 1997 .

[24]  Anthony A. P. Koppers,et al.  ArArCALC-software for 40 Ar/ 39 Ar age calculations , 2002 .

[25]  P. Beekman.  THE PLIOCENE AND QUATERNARY VOLGANISM IN THE HASAN DAĞ-MELENDİZ DAĞ REGION , 1965 .

[26]  R. Cas,et al.  A reconnaissance of U-Pb zircon ages in the Cerro Galan system, NW Argentina: Prolonged magma residence, crystal recycling, and crustal assimilation , 2011 .

[27]  T. M. Harrison,et al.  Constraints on Hadean zircon protoliths from oxygen isotopes, Ti‐thermometry, and rare earth elements , 2007 .

[28]  G. Wörner,et al.  Geochronology (40Ar/39Ar, K-Ar and He-exposure ages) of Cenozoic magmatic rocks from Northern Chile (18-22°S): implications for magmatism and tectonic evolution of the central Andes , 2000 .

[29]  P. Reiners,et al.  New Insights into Crustal Contributions to Large-volume Rhyolite Generation in the Mid-Tertiary Sierra Madre Occidental Province, Mexico, Revealed by U–Pb Geochronology , 2008 .

[30]  R. Steiger,et al.  Subcommission on geochronology: Convention on the use of decay constants in geo- and cosmochronology , 1977 .

[31]  B. Jicha,et al.  40Ar/39Ar chronostratigraphy of Altiplano-Puna volcanic complex ignimbrites reveals the development of a major magmatic province , 2011 .

[32]  P. Brenchley,et al.  Late Quaternary rhyolitic eruptions from the Acigöl Complex, central Turkey , 1995, Journal of the Geological Society.

[33]  Alain Gourgaud,et al.  Ignimbrites of Cappadocia (Central Anatolia, Turkey): petrology and geochemistry , 1998 .

[34]  K. Howard,et al.  Correlation of the Peach Springs Tuff, a large-volume Miocene ignimbrite sheet in California and Arizona , 1986 .

[35]  J. D. Miller,et al.  Precise U‐Pb ages of Duluth Complex and related mafic intrusions, northeastern Minnesota: Geochronological insights to physical, petrogenetic, paleomagnetic, and tectonomagmatic processes associated with the 1.1 Ga Midcontinent Rift System , 1993 .

[36]  P. Renne,et al.  Intercalibration of standards, absolute ages and uncertainties in 40Ar/39Ar dating , 1998 .

[37]  J. Wooden,et al.  Residence, Resorption and Recycling of Zircons in Devils Kitchen Rhyolite, Coso Volcanic Field, California , 2004 .

[38]  P. Renne,et al.  Implications of pre-eruptive magmatic histories of zircons for U–Pb geochronology of silicic extrusions , 2008 .

[39]  A. Schmitt,et al.  Voluminous low δ18O magmas in the late Miocene Heise volcanic field, Idaho: Implications for the fate of Yellowstone hotspot calderas , 2007 .

[40]  P. Renne,et al.  A test for systematic errors in 40Ar/39Ar geochronology through comparison with U/Pb analysis of a 1.1-Ga rhyolite , 2000 .

[41]  Catherine Deniel,et al.  Le volcanisme quaternaire d'Anatolie centrale (Turquie): association de magmatismes calco-alcalin et alcalin en domaine de convergence , 1995 .

[42]  D. DePaolo,et al.  Neodymium isotopic evidence for decreasing crustal contributions to Cenozoic ignimbrites of the western United States: Implications for the thermal evolution of the Cordilleran crust , 1993 .

[43]  F. Brown,et al.  Low-temperature alteration of volcanic glass: Hydration, Na, K, 18O and Ar mobility , 1985 .

[44]  R. Schumacher,et al.  Problems of Stratigraphic Correlation and New K-Ar Data for Ignimbrites from Cappadocia, Central Turkey , 1996 .

[45]  M. McCulloch,et al.  Pb−Sr−Nd−O isotopic constraints on the origin of rhyolites from the Taupo Volcanic Zone of New Zealand: evidence for assimilation followed by fractionation from basalt , 1994 .

[46]  A. Schmitt.  Uranium Series Accessory Crystal Dating of Magmatic Processes , 2011 .

[47]  S. L. Silva.  Altiplano-Puna volcanic complex of the central Andes , 1989 .

[48]  B. Houghton,et al.  An exceptionally widespread ignimbrite with implications for pyroclastic flow emplacement , 1995, Nature.

[49]  E. Şen,et al.  Volcanological evolution of Mount Erciyes stratovolcano and origin of the Valibaba Tepe ignimbrite (Central Anatolia, Turkey) , 2003 .

[50]  Juan Xu,et al.  Reappraisement and refinement of zircon U-Pb isotope and trace element analyses by LA-ICP-MS , 2010 .

[51]  Eugene I. Smith,et al.  Systematics of xenocrystic contamination: preservation of discrete feldspar populations at McCullough Pass Caldera revealed by 40Ar/39Ar dating , 2001 .

[52]  B. Jicha,et al.  Volcanic biotite-sanidine 40Ar/39Ar age discordances reflect Ar partitioning and pre-eruption closure in biotite , 2010 .

[53]  J. Valley,et al.  U–Pb zircon geochronology of silicic tuffs from the Timber Mountain/Oasis Valley caldera complex, Nevada: rapid generation of large volume magmas by shallow-level remelting , 2006 .

[54]  A. Gurel,et al.  Revised volcanostratigraphy of the Upper Miocene to Lower Pliocene Ürgüp Formation, Central Anatolian volcanic province, Turkey , 2010 .

[55]  Jean-Luc Froger,et al.  Stratigraphy and age of the Cappadocia ignimbrites, Turkey: reconciling field constraints with paleontologic, radiochronologic, geochemical and paleomagnetic data , 2005 .

[56]  M. Walters,et al.  The Geysers - Cobb Mountain Magma System, California (Part 1): U-Pb zircon ages of volcanic rocks, conditions of zircon crystallization and magma residence times , 2003 .

[57]  N. Evans,et al.  Acigöl rhyolite field, Central Anatolia (part 1): high-resolution dating of eruption episodes and zircon growth rates , 2011 .