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Antecrysts are relic or co-magmatic phenocrysts that are common in volcanic rocks of arc settings. Their occurrence is a foundation of the crystal mush paradigm for crustal magmatism, although the putative mush is rarely erupted. The 13.6 ka Belfond eruption (Saint Lucia) produced dacite lava with glass-bearing diorite enclaves, previously shown to have synchronous zircon crystallisation extending to eruption. The cummingtonit...
Priming and eruption of andesite magmas at Taranaki volcano recorded in plagioclase phenocrystsNARA Subscribed
Plagioclase phenocrysts in pre-historic andesites provide insight to the dynamics of magma formation and eruption at Taranaki volcano, New Zealand. The phenocryst population has a diversity of relic cores and a total in situ 87 Sr/ 86 Sr range of 0.70440–0.70486. Within-sample 87 Sr/ 86 Sr variations of 0.00018 to 0.00043 indicate that many phenocrysts are antecrysts and/or xenocrysts, derived from multiple crystal mush bodies...
Re‐evaluation of the Roseau Tuff eruptive sequence and other ignimbrites in Dominica, Lesser AntillesNARA Subscribed
The island of Dominica hosts several ignimbrites, including the Roseau Tuff, thought to represent the largest eruption in the Caribbean in the past 200 000 years. The volcanic stratigraphy of the island is poorly understood due to limited outcrops and a paucity of geochemical and geochronological data. The discovery of a new fully accessible exposure of three ignimbrites intercalated with paleosols provides an opportunity to r...
A suite of deep‐sea cores were collected along transects up to 100 km across the fore‐arc and back‐arc regions of the predominantly submarine Kermadec arc near Raoul and Macauley islands, southwest Pacific. The cores reveal a macroscopic tephra record extending back >50 ka. This is a significant addition to the dated record of volcanism, previously restricted to fragmented late Holocene records exposed on the two islands. The...
A multi‐proxy record of changing environments from ca. 30 000 to 9000 cal. a BP: Onepoto maar palaeolake, Auckland, New ZealandNARA Subscribed
We present a high‐resolution record of lacustrine sedimentation spanning ca. 30 000 to 9000 cal. a BP from Onepoto maar, northern North Island, New Zealand. The multi‐proxy record of environmental change is constrained by tephrochronology and accelerator mass spectrometric 14 C ages and provides evidence for episodes of rapid environmental change during the Last Glacial Coldest Period (LGCP) and Last Glacial–Interglacial Trans...
Rapid change in early Holocene environments inferred from Lake Pupuke, Auckland City, New ZealandNARA Subscribed
Sediment cores from Lake Pupuke in Auckland City, New Zealand, contain a high‐resolution millennial to centennial‐scale record of changing climate and catchment hydrology spanning the past ca. 10 000 years. Here, we focus on the period between 9500 ± 25 and 7000 ± 155 cal. yr BP during which grain size, diatom palaeoecology, biogenic silica concentrations, sediment elemental and carbon isotope geochemistry reflect changes in s...
Towards a comprehensive distal andesitic tephrostratigraphic framework for New Zealand based on eruptions from Egmont volcanoNARA Subscribed
The chronology and glass composition of 43 andesitic tephra layers in palaeolake sediments in northern New Zealand provide the basis for a fine‐resolution tephrostratigraphy of the interval 10–70 cal. ka. Their ages are constrained by 14 interbedded, (mostly) well‐dated rhyolitic tephra layers. The andesitic tephra have the potential to subdivide time intervals (1–5 kyr) bracketed by well known rhyolitic layers, including peri...