Bracketing ages for the formation of the Ring Creek lava flow, Mount Garibaldi volcanic field, southwestern British Columbia

The Ring Creek lava flow, extending from Opal Cone, generally is considered to be the youngest volcanic feature in the southern section of the Mount Garibaldi volcanic field, southwestern British Columbia. An in situ stump dated 10 650 ± 70 BP (Beta 43865) obtained from a raised delta partially overridden by the lava flow indicates that the lava was extruded after ca. 10.7 ka. At the Skookum Creek and Mamquam River confluence, sediments eroded from the Ring Creek lava flow form an alluvial fan that contains charcoal dated 9360 ± 160 BP (Beta 38914), which indicates that the extrusion probably occurred before ca. 9.3 ka. Thus these radiocarbon ages bracket the age of the Ring Creek lava flow and indicate that volcanic activity in the southern section of the Mount Garibaldi volcanic field has been dormant since at least ca. 9.3 ka.

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In situ quantification of crystallisation kinetics of plagioclase and clinopyroxene in basaltic magma: Implications for lava flow

Earth and Planetary Science Letters ◽

10.1016/j.epsl.2021.117016 ◽

2021 ◽

Vol 568 ◽

pp. 117016

Author(s):

Nolwenn Le Gall ◽

Fabio Arzilli ◽

Giuseppe La Spina ◽

Margherita Polacci ◽

Biao Cai ◽

...

Keyword(s):

Lava Flow ◽

Basaltic Magma ◽

Crystallisation Kinetics ◽

Kinetics Of

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Revisiting the age of the Jumento volcano, Chichinautzin Volcanic Field (Central Mexico), using in situ-produced cosmogenic 10Be

Journal of Volcanology and Geothermal Research ◽

10.1016/j.jvolgeores.2018.10.005 ◽

2018 ◽

Vol 366 ◽

pp. 112-119 ◽

Cited By ~ 4

Author(s):

Jesús Alcalá-Reygosa ◽

José Luis Arce ◽

Irene Schimmelpfennig ◽

Esperanza Muñoz Salinas ◽

Miguel Castillo Rodríguez ◽

...

Keyword(s):

Volcanic Field ◽

Central Mexico ◽

Cosmogenic 10Be

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Reconstructing lava flow emplacement histories with rheological and morphological analyses: the Harrat Rahat volcanic field, Kingdom of Saudi Arabia

Bulletin of Volcanology ◽

10.1007/s00445-018-1259-4 ◽

2018 ◽

Vol 80 (12) ◽

Cited By ~ 5

Author(s):

Hannah R. Dietterich ◽

Drew T. Downs ◽

Mark E. Stelten ◽

Hani Zahran

Keyword(s):

Saudi Arabia ◽

Lava Flow ◽

Volcanic Field ◽

Kingdom Of Saudi Arabia ◽

Harrat Rahat ◽

Lava Flow Emplacement

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Prescribing practices of endocrine therapy for ductal carcinoma in situ in British Columbia

Current Oncology ◽

10.3747/co.25.3795 ◽

2018 ◽

Vol 25 (2) ◽

pp. 133 ◽

Cited By ~ 1

Author(s):

A.T. Chaudhry ◽

T.A. Koulis ◽

C. Speers ◽

R.A. Olson

Keyword(s):

British Columbia ◽

Endocrine Therapy ◽

Ductal Carcinoma In Situ ◽

Carcinoma In Situ ◽

Ductal Carcinoma ◽

Population Based ◽

Cox Regression Analysis ◽

Treatment Centre ◽

Er Status

Purpose The mainstay of treatment for ductal carcinoma in situ (dcis) involves surgery in the form of mastectomy or lumpectomy. Inconsistency in the use of endocrine therapy (et) for dcis is evident worldwide. We sought to assess the variation in et prescribing for patients with dcis across a population-based radiotherapy (rt) program and to identify variables that predict its use.Methods Data from a breast cancer database were obtained for women diagnosed with dcis in British Columbia from 2009 to 2014. Associations between et use and patient characteristics were assessed by chi-square test and multilevel multivariate logistic regression. The Kaplan–Meier method, with propensity score matching and Cox regression analysis, was used to assess the effects of et on overall survival (os) and relapse-free survival (rfs).Results For the 2336 dcis patients included in the study, et use was 13% in dcis patients overall, and 17% in patients with estrogen receptor–positive (er+) tumours treated with breast-conserving surgery and rt. Significant variation in et use by treatment centre was observed (range: 8%–23%; p < 0.001), and prescription of et by individual oncologists varied in the range 0%–40%. After controlling for confounding factors, age less than 50 years [odds ratio (or): 1.72; p = 0.01], treatment centre, er+ status (or: 5.33; p < 0.001), and rt use (or: 1.77; p < 0.001) were significant predictors of et use. No difference in os or rfs with the use of et was observed.Conclusions In this population-based analysis, 13% of patients with dcis in British Columbia received et, with variation by treatment centre (8%–23%) and individual oncologist (0%–40%). Age less than 50 years, er+ status, and rt use were most associated with et use.

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Over 16,000 Years of Fire Frequency Determined from AMS Radiocarbon Dating of Soil Charcoal in an Alluvial Fan at Bear Flat, Northeastern British Columbia

Radiocarbon ◽

10.1017/s0033822200038868 ◽

2006 ◽

Vol 48 (3) ◽

pp. 435-450 ◽

Cited By ~ 10

Author(s):

A J Timothy Jull ◽

Marten Geertsema

Keyword(s):

British Columbia ◽

Radiocarbon Dating ◽

Large Scale ◽

Fire Frequency ◽

Alluvial Fan ◽

Before Present ◽

Ams Radiocarbon Dating ◽

Soil Charcoal ◽

Large Fires ◽

Millennial Time Scale

We present results of radiocarbon dating of charcoal from paleosols and buried charcoal horizons in a unique sequence, which potentially records the last 36,000 yr, from a fan at Bear Flat, British Columbia (BC) (56°16'51’N, 121°13'39”W). Evidence for forest-fire charcoal is found over the last 13,500 ± 110 14C yr before present (BP) or 16,250 ± 700 cal BP. The study area is located east of the Rocky Mountains in an area that was ice-free at least 13,970 ± 170 14C yr BP (17,450–16,150 cal BP) ago. The latest evidence of fire is during the Medieval Warm Period (MWP). The charcoal ages show a periodicity in large fires on a millennial scale through the Holocene—an average of 4 fires per thousand years. Higher fire frequencies are observed between 2200 to 2800 cal BP, ∼5500 and ∼6000 cal BP, ∼7500 to 8200 cal BP, and 9000 to 10,000 cal BP. These intervals also appear to be times of above-average aggradation of the fan. We conclude that fire frequency is related to large-scale climatic events on a millennial time scale.

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The Sisters Creek Formation: Pleistocene sediments representing a nonglacial interval in southwestern British Columbia at about 18 ka

Canadian Journal of Earth Sciences ◽

10.1139/e95-065 ◽

1995 ◽

Vol 32 (6) ◽

pp. 758-767 ◽

Cited By ~ 21

Author(s):

Stephen R. Hicock ◽

Olav B. Lian

Keyword(s):

British Columbia ◽

Glacial Maximum ◽

Time Space ◽

Late Wisconsinan ◽

Sand And Gravel ◽

New Time

Sisters Creek Formation is formally defined, stratotypes are established for it, and the time–space chart is updated for the Fraser Lowland, southwestern British Columbia. The Sisters Creek is a Pleistocene formation comprising in situ and reworked organic-rich sediments, and nonorganic silt, sand, and gravel. The formation was deposited during the Port Moody interstade (within the Late Wisconsinan Fraser Glaciation; δ18O stage 2) between the Coquitlam stade (early Fraser Glaciation) and the main Vashon stadial maximum that occurred about 14.5 ka. The Sisters Creek Formation represents a glacial recession in southwestern British Columbia that generally coincided with the timing of the last global glacial maximum. The new time–space chart implies that, in Fraser Lowland, the Fraser Glaciation represents the rapid advances and retreats of glacial lobes issuing from surrounding mountains, which remained ice-covered during interstades.

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Geoheritage values of one of the largest maar craters in the Arabian Peninsula: the Al Wahbah Crater and other volcanoes (Harrat Kishb, Saudi Arabia)

Open Geosciences ◽

10.2478/s13533-012-0125-8 ◽

2013 ◽

Vol 5 (2) ◽

Cited By ~ 5

Author(s):

Mohammed Moufti ◽

Károly Németh ◽

Nabil El-Masry ◽

Atef Qaddah

Keyword(s):

Saudi Arabia ◽

Lava Flow ◽

Arabian Peninsula ◽

Volcanic Hazards ◽

Scoria Cone ◽

Volcanic Field ◽

Flow Surface ◽

Geological Features ◽

A Site ◽

Tephra Ring

AbstractAl Wahbah Crater is one of the largest and deepest Quaternary maar craters in the Arabian Peninsula. It is NW-SE-elongated, ∼2.3 km wide, ∼250 m deep and surrounded by an irregular near-perpendicular crater wall cut deeply into the Proterozoic diorite basement. Very few scientific studies have been conducted on this unique site, especially in respect to understanding the associated volcanic eruption processes. Al Wahbah and adjacent large explosion craters are currently a research subject in an international project, Volcanic Risk in Saudi Arabia (VORiSA). The focus of VORiSA is to characterise the volcanic hazards and eruption mechanisms of the vast volcanic fields in Western Saudi Arabia, while also defining the unique volcanic features of this region for use in future geoconservation, geoeducation and geotourism projects. Al Wahbah is inferred to be a maar crater that formed due to an explosive interaction of magma and water. The crater is surrounded by a tephra ring that consists predominantly of base surge deposits accumulated over a pre-maar scoria cone and underlying multiple lava flow units. The tephra ring acted as an obstacle against younger lava flows that were diverted along the margin of the tephra ring creating unique lava flow surface textures that recorded inflation and deflation processes along the margin of the post-maar lava flow. Al Wahbah is a unique geological feature that is not only a dramatic landform but also a site that can promote our understanding of complex phreatomagmatic monogenetic volcanism. The complex geological features perfectly preserved at Al Wahbah makes this site as an excellent geotope and a potential centre of geoeducation programs that could lead to the establishment of a geopark in the broader area at the Kishb Volcanic Field.

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Volcanic activity and gas emissions along the South Sandwich Arc

Bulletin of Volcanology ◽

10.1007/s00445-020-01415-2 ◽

2020 ◽

Vol 83 (1) ◽

Author(s):

Emma J. Liu ◽

Kieran Wood ◽

Alessandro Aiuppa ◽

Gaetano Giudice ◽

Marcello Bitetto ◽

...

Keyword(s):

Carbon Isotope ◽

Volcanic Activity ◽

Emission Rate ◽

Tectonic Setting ◽

Hydrothermal Systems ◽

Molar Ratio ◽

The South ◽

Gas Emissions ◽

Volcanic Arc

AbstractThe South Sandwich Volcanic Arc is one of the most remote and enigmatic arcs on Earth. Sporadic observations from rare cloud-free satellite images—and even rarer in situ reports—provide glimpses into a dynamic arc system characterised by persistent gas emissions and frequent eruptive activity. Our understanding of the state of volcanic activity along this arc is incomplete compared to arcs globally. To fill this gap, we present here detailed geological and volcanological observations made during an expedition to the South Sandwich Islands in January 2020. We report the first in situ measurements of gas chemistry, emission rate and carbon isotope composition from along the arc. We show that Mt. Michael on Saunders Island is a persistent source of gas emissions, releasing 145 ± 59 t day−1 SO2 in a plume characterised by a CO2/SO2 molar ratio of 1.8 ± 0.2. Combining this CO2/SO2 ratio with our independent SO2 emission rate measured near simultaneously, we derive a CO2 flux of 179 ± 76 t day−1. Outgassing from low temperature (90–100 °C) fumaroles is pervasive at the active centres of Candlemas and Bellingshausen, with measured gas compositions indicative of interaction between magmatic fluids and hydrothermal systems. Carbon isotope measurements of dilute plume and fumarole gases from along the arc indicate a magmatic δ13C of − 4.5 ± 2.0‰. Interpreted most simply, this result suggests a carbon source dominated by mantle-derived carbon. However, based on a carbon mass balance from sediment core ODP 701, we show that mixing between depleted upper mantle and a subduction component composed of sediment and altered crust is also permissible. We conclude that, although remote, the South Sandwich Volcanic Arc is an ideal tectonic setting in which to explore geochemical processes in a young, developing arc.

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Small Lava Caves as Possible Exploratory Targets on Mars: Analogies Drawn from UAV Imaging of an Icelandic Lava Field

Remote Sensing ◽

10.3390/rs12121970 ◽

2020 ◽

Vol 12 (12) ◽

pp. 1970

Author(s):

Lydia Sam ◽

Anshuman Bhardwaj ◽

Shaktiman Singh ◽

F. Javier Martin-Torres ◽

Maria-Paz Zorzano ◽

...

Keyword(s):

Lava Flow ◽

Vital Role ◽

Low Gravity ◽

Physical Weathering ◽

Order Of Magnitude ◽

Aerial Vehicle ◽

High Resolution Images ◽

Air Circulation ◽

Geomorphological Analysis

Volcanic-aeolian interactions and processes have played a vital role in landscape evolution on Mars. Martian lava fields and associated caves have extensive geomorphological, astrobiological, and in-situ resource utilization (ISRU) implications for future Mars missions which might be focused on subsurface exploration. Although several possible cave “skylights” of tens to >100 m diameter have been spotted in lava fields of Mars, there is a possibility of prevalence of meter-scale features which are an order of magnitude smaller and difficult to identify but could have vital significance from the scientific and future exploration perspectives. The Icelandic volcanic-aeolian environment and fissure volcanoes can serve as analogs to study lava flow-related small caves such as surface tubes, inflationary caves, liftup caves, and conduits. In the present work, we have tried to explore the usability of unmanned aerial vehicle (UAV)-derived images for characterizing a solidified lava flow and designing a sequential methodology to identify small caves in the lava flow. In the mapped area of ~0.33 km2, we were able to identify 81 small cave openings, five lava flow morphologies, and five small cave types using 2 cm/pixel high-resolution images. The results display the usefulness of UAV imaging for such analogous research, and also highlight the possibility of the widespread presence of similar small cave openings in Martian lava fields. Such small openings can facilitate optimal air circulation within the caves while sheltering the insides from physical weathering and harmful radiations. Using the available best resolution remote sensing images, we extend the analogy through the contextual and geomorphological analysis of several possible pit craters in the Tharsis region of Mars, in a region of extremely vesicular and fragile lava crust with pahoehoe-type morphology. We report two possible pit craters in this region, with diameters as small as ~20 m. The possibility that such small cave openings can lead to vast subterranean hollow spaces on Mars cannot be ruled out considering its low gravity.

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