Results 71 to 80 of about 9,430 (230)

Progressively Fenitised Schist and Carbonatitic Clasts From a Metasomatic Aureole Beneath the Alkalic Dunedin Volcano, Otago, New Zealand

New Zealand Journal of Geology and Geophysics, Volume 69, Issue 2, June 2026.
Clasts of albite‐porphyroblastic quartzofeldspathic schist, derived from the Otago Schist basement, occur within the Port Chalmers Breccia, a diatreme at the centre of the Dunedin stratovolcano, New Zealand. Schists have undergone varying degrees of replacement reactions (at temperatures of 300° to >500°C) producing hornfelses, with Ca‐ and K‐enriched ...
Alan F. Cooper
wiley   +1 more source

Tephra segregation profiles based on disdrometer observations and tephra dispersal modeling: Vulcanian eruptions of Sakurajima volcano, Japan

Earth, Planets and Space
The profile of tephra concentration along a volcanic plume (i.e., the tephra segregation profile) is an important source parameter for the simulation of tephra transport and deposition and thus for the tephra sedimentation load.
Kosei Takishita, Alexandros-Panagiotis Poulidis, Masato Iguchi   +2 more
doaj   +1 more source

Magma Budget From Lava and Tephra Volumes Erupted During the 25-26 October 2013 Lava Fountain at Mt Etna

Frontiers in Earth Science, 2018
Determining the volume of the various types of products of a highly frequent active volcano can be very difficult, especially if most of them are deposited on a growing volcanic cone.
Daniele Andronico, Boris Behncke, Emanuela De Beni, Antonino Cristaldi, Simona Scollo, Manuela Lopez, Maria D. Lo Castro   +6 more
doaj   +1 more source

Ages on weathered Plio-Pleistocene tephra sequences, western North Island, New Zealand

, 2001
Using the zircon fission-track method, we have obtained five ages on members of two strongly-weathered silicic, Pliocene-Pleistocene tephra sequences, the Kauroa and Hamilton Ash formations, in western North Island, New Zealand.
Liddell, Ivan J., Lowe, David J., Tippett, J. Mark, Horrocks, Joanna L., Briggs, Roger M., Kamp, Peter J.J.   +5 more
core  

Sakurajima-Satsuma (Sz-S) and Noike-Yumugi (N-Ym) tephras: new tephrochronological marker beds for the last deglaciation, southern Kyushu, Japan

, 2011
Two prominent tephras, Sakurajima-Satsuma (Sz-S) erupted from Sakurajima volcano and Noike-Yumugi (N-Ym) erupted from Kuchierabujima Island, provide new key marker beds for dating and synchronizing palaeoenvironmental and archaeological records in the ...
Murata, Masanori, Masanori Murata, Moriwaki, Hiroshi, Hiroshi Machida, Lowe, David J., Takehiko Suzuki, Ikehara, Minoru, Hiroshi Moriwaki, David J. Lowe, Minoru Ikehara, Suzuki, Takehiko, Machida, Hiroshi   +11 more
core   +1 more source

VOLCORE_2021 - a 2021 update of the global database of visible tephra layers sampled by ocean drilling

, 2021
VOLCORE_2021 is an update on the original VOLCORE data released in 2020. Change notes are listed within the VOLCORE_2021 data file. A major update is the new merged Layers-Holes-AgeDepth sheet, enabling easier manipulation of the data.
Barnard, Nicholas H, Mahony, Sue H, Rougier, Jonathan C, Sparks, R Stephen J   +3 more
core   +1 more source

Vertical and Spatial Geochemical Variations of Nishinoshima Volcaniclastic Deposits, Japan, During Episode 4

New Zealand Journal of Geology and Geophysics, Volume 69, Issue 2, June 2026.
Nishinoshima is a volcanic island in the Ogasawara Arc that has exhibited intermittent activity since 2013, including four major eruptive episodes: 2013–2015 (Episode 1), 2017 (Episode 2), 2018 (Episode 3), and 2019–2020 (Episode 4). Previous studies reported a change in eruption style—from a Strombolian eruption with lava flows (Episode 1 to the early
Erika Tanaka, Kenta Yoshida, Tomoki Sato, Yoshiro Nishio, Yoshihiko Tamura   +4 more
wiley   +1 more source

Late Holocene explosive activity of the Atsonupuri volcano (Iturup Island, Southern Kuril Islands): preliminary results [PDF]

Геосистемы переходных зон
The first results of the study of Late Holocene activity of the Atsonupuri volcano (Iturup Island, Southern Kuril Islands) obtained during field work in 2013–2014 are presented. On the basis of tephrochronological studies and radiocarbon dating, it was
Degterev, Artem V.
doaj   +1 more source

A Machine‐Learning Classification for Torlesse Composite Terrane Petrofacies and its Application to Sediment Provenance

New Zealand Journal of Geology and Geophysics, Volume 69, Issue 2, June 2026.
The Torlesse Composite Terrane (TCT) forms many of the mountain ranges in Aotearoa New Zealand and has provided enormous quantities of coarse‐grained sediment to Te Riu‐a‐Maui/Zealandia's basins since the mid‐Cretaceous. Tracing the provenance of these sediments to certain regions of the TCT can indirectly reconstruct exhumation patterns associated ...
Matthew O. Parker, David E. Dempsey, Matthew W. Sagar, Kari N. Bassett, Alexander R. L. Nichols, Greg H. Browne   +5 more
wiley   +1 more source

Tephra data from varved lakes of the Last Glacial–Interglacial Transition: towards a global inventory and better chronologies on the Varved Sediments Database (VARDA) [PDF]

Earth System Science Data
The Varved Sediments Database (VARDA) was launched in 2020 and aimed to establish a community database for annually resolved chronological archives with their associated high-resolution proxy records.
A. Beckett, C. Blanchet, A. Brauser, R. Kearney, C. Martin-Puertas, I. Matthews, K. Mittelbach, A. Palmer, A. Ramisch, A. Ramisch, A. Brauer   +10 more
doaj   +1 more source