The fracture system and the melt emplacement beneath the Deception Island active volcano, South Shetland Islands, Antarctica

AbstractA new magnetotelluric (MT) survey, along with new topographic parametric sonar (TOPAS) profiles and geological field observations, were carried out on the Deception Island active volcano. 3-D resistivity models reveal an ENE–WSW elongated conductor located at a depth between two and ten kilometres beneath the south-eastern part of the island, which we interpret as a combination of partial melt and hot fluids. The emplacement of the melt in the upper crust occurs along the ENE–WSW oriented, SSE dipping regional normal fault zone, which facilitates melt intrusion at shallower levels with volcanic eruptions and associated seismicity. Most of the onshore and offshore volcanic rocks are deformed by high-angle normal and sub-vertical faults with dominant dip-slip kinematics, distributed in sets roughly parallel and orthogonal to the major ENE–WSW regional tectonic trends. Faults development is related to perturbations of the regional stress field associated with magma chamber overpressure and deflation in a regional setting dominated by NW–SE to NNW–SSE extension.

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DecTephra: A new database of Deception Island’s tephra record (Antarctica

10.5194/egusphere-egu21-2075 ◽

2021 ◽

Author(s):

Joaquin Hopfenblatt ◽

Adelina Geyer ◽

Meritxell Aulinas ◽

Antonio Polo Sánchez ◽

Antonio Álvarez-Valero

Keyword(s):

Volcanic Hazard ◽

Active Volcano ◽

Lacustrine Sediment ◽

South Shetland Islands ◽

Deception Island ◽

The South ◽

Shetland Islands ◽

Tephra Layers ◽

The Antarctic ◽

Eruption Record

Deception Island is the most active volcano in the South Shetland Islands (Antarctica) with more than 20 eruptions in the in the last two centuries, including the 1967, 1969 and 1970 most recent eruptive events, and three episodes of volcanic unrest since 1990 (1992, 1999 and 2014-2015). Since the discovery of Deception island in 1820, the number of scientific bases, touristic activities, and air and vessel traffic in the region, have considerably increased. Only the Antarctic Peninsula region, together with the South Shetland Islands, hosts 25 research stations and 3 summer field camps, which are located inside or within a 150 km radius distance from this active volcano. Nearby, the Palmer Archipelago and the north-western coast of the Antarctic Peninsula are both important tourist destinations exceeding 30,000 visitors per year with a significant increase in vessel traffic during the tourist season. This escalation in the amount of exposed infrastructure and population to a future eruption of Deception Island clearly urges the need to advancing our knowledge of the island&#8217;s volcanic and magmatic history and developing improved vulnerability analyses and long-term volcanic hazard assessments. However, past attempts to construct a volcanic hazard map of Deception have always been limited by the lack of a complete eruption record. In this sense, volcanic ash layers found in marine and lacustrine sediment cores, and glaciers outside Deception Island can provide valuable information to: (i) determine the size and explosiveness of past eruptive events; (ii) assess the extent of their related hazards (e.g. ash fall out); (iii) complete the eruption record of the island; and (iv) estimate the island&#8217;s eruption recurrence over time.In this work, we provide a detailed, and up-to-date, revision of the current knowledge on Deception Island&#8217;s tephra record. &#160;For this, we have compiled the DecTephra (Deception Island Tephra Record) database, which seeks recording the most relevant information of all up today known tephra layers with Deception Island as presumed source vent. DecTephra database includes 335 tephra layers (including cryptotephras) found in marine/lacustrine sediment and ice cores. For each tephra layer, we have compiled information regarding: (i) location (e.g. latitude, longitude, region) and characteristics of the sampling site (e.g. length of the sediment or ice core); and (ii) tephra characteristics (e.g. age, chemistry, granulometry). The analysis of the information included in this new database shows that Deception Island&#8217;s tephras can be observed at numerous proximal (< 150 km) sampling sites distributed all along the South Shetland Islands but also as far as in the Scotia Sea (> 1,000 km) and the South Pole (> 2,900 km). Also, identified isochronous tephra horizons allow defining periods of higher explosive eruptive activity in the island during the Holocene.This research is part of POLARCSIC and PTIVolcan research initiatives. This research was partially funded by the MINECO projects VOLCLIMA (CGL2015-72629-EXP) and VOLGASDEC (PGC2018-095693-B-I00)(AEI/FEDER, UE). A.P.S is grateful for his JAE_Intro scholarship (JAEINT_20_00670).

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Investigations of the 1967 and 1969 volcanic eruptions on Deception Island, South Shetland Islands

Polar Record ◽

10.1017/s003224740006544x ◽

1969 ◽

Vol 14 (93) ◽

pp. 823-827 ◽

Cited By ~ 4

Author(s):

P. E. Baker

Keyword(s):

Volcanic Eruptions ◽

South Shetland Islands ◽

Deception Island ◽

Shetland Islands

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Lithostratigraphy and volcanic evolution of Deception Island, South Shetland Islands

Antarctic Science ◽

10.1017/s0954102001000281 ◽

2001 ◽

Vol 13 (2) ◽

pp. 188-209 ◽

Cited By ~ 56

Author(s):

J.L. Smellie

Keyword(s):

Small Volume ◽

Active Volcano ◽

South Shetland Islands ◽

Caldera Collapse ◽

Deception Island ◽

Shetland Islands ◽

History Of ◽

The Antarctic ◽

Entire Island ◽

Basaltic Shield

Deception Island is the most active volcano in the Antarctic Peninsula region. It is a large basalt–andesite shield volcano with a 10 km-wide restless caldera (Port Foster) and a complicated history of pre- and post-caldera eruptions. There has been no modern volcanological investigation of the entire island and it remains a largely unknown volcanic hazard. The pre-caldera period on the island began with the low-energy eruption of tephras from multiple centres (Fumarole Bay Formation), possibly by subaqueous fire fountaining during shoaling and likely initial emergence of the volcano. It was followed by subaerial effusive to weakly pyroclastic (Strombolian/Hawaiian) activity that constructed a small basaltic shield (Basaltic Shield Formation), and a large eruption that vented about 30 km3 of magma (Outer Coast Tuff Formation). The latter eruption may have been triggered by an influx of compositionally different magma into the main chamber feeding the volcano, and the evidence suggests that it was associated with a significant involvement with water (seawater?). The eruption was followed by caldera collapse, and there have been several small incremental caldera “collapses” subsequently. Post-caldera eruptions were all small-volume and predominantly phreatomagmatic (Baily Head and Pendulum Cove formations), but magmatic eruptions constructed several small lava deltas around the coast and also produced a local carapace of scoria and thin lavas, particularly around the caldera rim (Stonethrow Ridge Formation). Although the caldera is presently resurging, interpretation of the eruptive history of the island suggests that future eruptions are likely to be small in volume and will have only a limited regional impact.

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Exploring the plant environmental DNA diversity in soil from two sites on Deception Island (Antarctica, South Shetland Islands) using metabarcoding

Antarctic Science ◽

10.1017/s0954102021000274 ◽

2021 ◽

pp. 1-10

Author(s):

Micheline Carvalho-Silva ◽

Luiz Henrique Rosa ◽

Otávio H.B. Pinto ◽

Thamar Holanda Da Silva ◽

Diego Knop Henriques ◽

...

Keyword(s):

High Throughput Sequencing ◽

Crater Lake ◽

Environmental Dna ◽

Food Sources ◽

South Shetland Islands ◽

Deception Island ◽

Shetland Islands ◽

Operational Taxonomic Units ◽

First Time ◽

Impacted Site

Abstract The few Antarctic studies to date to have applied metabarcoding in Antarctica have primarily focused on microorganisms. In this study, for the first time, we apply high-throughput sequencing of environmental DNA to investigate the diversity of Embryophyta (Viridiplantae) DNA present in soil samples from two contrasting locations on Deception Island. The first was a relatively undisturbed site within an Antarctic Specially Protected Area at Crater Lake, and the second was a heavily human-impacted site in Whalers Bay. In samples obtained at Crater Lake, 84% of DNA reads represented fungi, 14% represented Chlorophyta and 2% represented Streptophyta, while at Whalers Bay, 79% of reads represented fungi, 20% represented Chlorophyta and < 1% represented Streptophyta, with ~1% of reads being unassigned. Among the Embryophyta we found 16 plant operational taxonomic units from three Divisions, including one Marchantiophyta, eight Bryophyta and seven Magnoliophyta. Sequences of six taxa were detected at both sampling sites, eight only at Whalers Bay and two only at Crater Lake. All of the Magnoliophyta sequences (flowering plants) represent species that are exotic to Antarctica, with most being plausibly linked to human food sources originating from local national research operator and tourism facilities.

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Fur seals, whales and tourists: a commercial history of Deception Island, Antarctica

Polar Record ◽

10.1017/s0032247409008651 ◽

2009 ◽

Vol 46 (3) ◽

pp. 210-221 ◽

Cited By ~ 15

Author(s):

J. Stephen Dibbern

Keyword(s):

South Shetland Islands ◽

Deception Island ◽

Commercial Activity ◽

Early 19Th Century ◽

Cruise Industry ◽

Shetland Islands ◽

Fur Seals ◽

History Of ◽

The Antarctic ◽

Antarctic Fur Seals

ABSTRACTDeception Island in the South Shetland Islands was the site of some of the earliest commercial activity to be carried out in the Antarctic with the early 19th century hunting of Antarctic fur seals. Nearly a century later it was the site of the most extensive anchorage for the reconstructed ships and ocean liners used as non-pelagic whale processing factories. Deception was also the site of what is the only successful land based commercial activity in Antarctic history. The Hektor whaling station operated in Whalers Bay from 1912 until 1931. Most of the remains of the station have now been obliterated by the volcanic activity that occurred in the late 1960s and 1970. By the later part of the twentieth century Deception Island had become a regular stop for the growing Antarctic tourist cruise industry. No other place in Antarctica has been so thoroughly identified with commercial activity.

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Chapter 7.1 Deception Island

Geological Society London Memoirs ◽

10.1144/m55-2018-56 ◽

2021 ◽

pp. M55-2018-56

Author(s):

A. Geyer ◽

D. Pedrazzi ◽

J. Almendros ◽

M. Berrocoso ◽

J. López-Martínez ◽

...

Keyword(s):

Ground Deformation ◽

South Shetland Islands ◽

Deception Island ◽

Research Activity ◽

Proper Understanding ◽

Volcanic Unrest ◽

Origin And Evolution ◽

Shetland Islands ◽

The Past ◽

Scientific Disciplines

AbstractDeception Island (South Shetland Islands) is one of the most active volcanoes in Antarctica, with more than 15 explosive eruptive events registered over the past two centuries. Recent eruptions (1967, 1969 and 1970) and volcanic unrest episodes in 1992, 1999 and 2014–15 demonstrate that the occurrence of future volcanic activity is a valid and pressing concern for scientists, logistic personnel and tourists that are visiting or are working on or near the island. Over the last few decades, intense research activity has been carried out on Deception Island to decipher the origin and evolution of this very complex volcano. To that end, a solid integration of related scientific disciplines, such as tectonics, petrology, geochemistry, geophysics, geomorphology, remote sensing, glaciology, is required. A proper understanding of the island's evolution in the past, and its present state, is essential for improving the efficiency in interpreting monitoring data recorded during volcanic unrest periods and, hence, for future eruption forecasting. In this chapter, we briefly present Deception Island's most relevant tectonic, geomorphological, volcanological and magmatic features, as well as the results obtained from decades of monitoring the island's seismic activity and ground deformation.

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Periphyton diversity in two different Antarctic lakes assessed using metabarcoding

Antarctic Science ◽

10.1017/s0954102021000316 ◽

2021 ◽

pp. 1-9

Author(s):

Paulo E.A.S. Câmara ◽

Láuren M.D. De Souza ◽

Otávio Henrique Bezerra Pinto ◽

Peter Convey ◽

Eduardo T. Amorim ◽

...

Keyword(s):

Dna Sequences ◽

High Throughput Sequencing ◽

Shannon Index ◽

South Shetland Islands ◽

King George Island ◽

Deception Island ◽

Maritime Antarctic ◽

Shetland Islands ◽

Antarctic Lakes ◽

Significant Difference

Abstract Antarctic lakes have generally simple periphyton communities when compared with those of lower latitudes. To date, assessment of microbial diversity in Antarctica has relied heavily on traditional direct observation and cultivation methods. In this study, sterilized cotton baits were left submerged for two years in two lakes on King George Island and Deception Island, South Shetland Islands (Maritime Antarctic), followed by assessment of diversity by metabarcoding using high-throughput sequencing. DNA sequences of 44 taxa belonging to four kingdoms and seven phyla were found. Thirty-six taxa were detected in Hennequin Lake on King George Island and 20 taxa were detected in Soto Lake on Deception Island. However, no significant difference in species composition was detected between the two assemblages (Shannon index). Our data suggest that metabarcoding provides a suitable method for the assessment of periphyton biodiversity in oligotrophic Antarctic lakes.

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