The White River Ash: largest Holocene Plinian tephra

2008 ◽  
Vol 45 (6) ◽  
pp. 693-700 ◽  
Author(s):  
J. F. Lerbekmo
Keyword(s):  
Grain Size ◽  
Far East ◽  
Yukon Territory ◽  
Square Root ◽  
Eruption Rate ◽  
Present Evidence ◽  
White River ◽  
The North ◽  
Bear Lake ◽  
Straight Line

The White River Ash is a bi-lobate tephra in eastern Alaska, Yukon Territory, and western Northwest Territories. Plinian-type eruptions produced the north lobe ∼1900 years BP and the larger east lobe ∼1250 years BP (14C years). Present evidence favors the vent for the east lobe to be beneath the Klutlan Glacier. East lobe pumice is not present atop Mt. Churchill, so the pumice there must belong to the north lobe and is also likely to have come from a vent beneath the Klutlan Glacier. Isopachs of the east lobe, now known to stretch as far east as Great Bear Lake, indicate an east lobe volume of ∼47 km3. Thickness and grain size of the east lobe decay in exponential fashion, producing straight line plots when the thickness half-distance and clast half-distance are plotted against the square root of the isopach area, the proximal slope being steeper than the distal. The east lobe eruption is indicated to have been into a wind of about 10 m/s and to have produced an eruptive cloud height of ∼45 km. The eruption rate was at least 2.8 × 108 kg/s.

Holocene climate recorded by magnetic properties of lake sediments in the Northern Rocky Mountains, USA

The Holocene ◽  
2019 ◽  
Vol 30 (3) ◽  
pp. 479-484
Author(s):  
Daniel P Maxbauer ◽  
Mark D Shapley ◽  
Christoph E Geiss ◽  
Emi Ito
Keyword(s):  
Grain Size ◽  
Magnetic Properties ◽  
Rocky Mountains ◽  
Future Research ◽  
Magnetic Minerals ◽  
Holocene Climate ◽  
Northern Rocky Mountains ◽  
The North ◽  
Lake Bottom ◽  
Northern Rockies

We present two hypotheses regarding the evolution of Holocene climate in the Northern Rocky Mountains that stem from a previously unpublished environmental magnetic record from Jones Lake, Montana. First, we link two distinct intervals of fining magnetic grain size (documented by an increasing ratio of anhysteretic to isothermal remanent magnetization) to the authigenic production of magnetic minerals in Jones Lake bottom waters. We propose that authigenesis in Jones Lake is limited by rates of groundwater recharge and ultimately regional hydroclimate. Second, at ~8.3 ka, magnetic grain size increases sharply, accompanied by a drop in concentration of magnetic minerals, suggesting a rapid termination of magnetic mineral authigenesis that is coeval with widespread effects of the 8.2 ka event in the North Atlantic. This association suggests a hydroclimatic response to the 8.2 ka event in the Northern Rockies that to our knowledge is not well documented. These preliminary hypotheses present compelling new ideas that we hope will both highlight the sensitivity of magnetic properties to record climate variability and attract more work by future research into aridity, hydrochemical response, and climate dynamics in the Northern Rockies.

scholarly journals Controlling Shipping Along the North European Trade Axis

1971 ◽  
Vol 24 (4) ◽  
pp. 553-556
Author(s):  
D. J. Lindsay
Keyword(s):  
Weather Conditions ◽  
North Coast ◽  
Baltic Basin ◽  
Long Distance ◽  
The North ◽  
Large Numbers ◽  
Straight Line ◽  
European Trade ◽  
Trade Route ◽  
The Baltic

By the North European Trade Axis is meant the trade route from Ushant and Land's End, up the English Channel, through the Dover Strait fanning out to serve eastern England, the north coast of continental Europe and leading to the Baltic Basin. Recent events in this area have left a feeling that some form of tightening of control is not only desirable, but is rapidly becoming imperative. There is a basic conflict between the two forms of shipping using the area: the local users who use the area more or less constantly, and the long-distance traders, usually much larger, which arrive in the area for a brief stay after a prolonged period at sea, which has usually been in good weather conditions. Frequently these latter ships have a very poor notion of the hornet's nest into which they are steaming when they arrive. The net result is all too often the same: the local users, with familiarity breeding contempt, wander about as they see fit, with scant regard for routing or the regulations; all too often the big ships arrive from sea with navigating staffs who are too confused, sometimes too ignorant—and sometimes too terrified—to do much more than blunder forward in a straight line hoping for the best. Quite obviously this is not a total picture, and there are large numbers of ships which navigate perfectly competently, but the minority of those which do not seem to be rising rapidly, and show every sign of continuing to increase.

SPATIAL LAYOUT OF THE SOVIET UNION TIMBER PROCESSING COMPLEX: THE IDEA BEHIND THE FIRST FIVE-YEAR PLAN

2021 ◽  
Vol 7 (3) ◽  
pp. 131-154
Author(s):  
Ivan V. ZYKIN
Keyword(s):  
Soviet Union ◽  
Large Scale ◽  
Far East ◽  
Spatial Layout ◽  
Capital Investments ◽  
Wood Industry ◽  
North West ◽  
The North ◽  
The Soviet Union ◽  
Central Regions

During the years of Soviet power, principal changes took place in the country’s wood industry, including in spatial layout development. Having the large-scale crisis in the industry in the late 1980s — 2000s and the positive changes in its functioning in recent years and the development of an industry strategy, it becomes relevant to analyze the experience of planning the spatial layout of the wood industry during the period of Stalin’s modernization, particularly during the first five-year plan. The aim of the article is to analyze the reason behind spatial layout of the Soviet wood industry during the implementation of the first five-year plan. The study is based on the modernization concept. In our research we conducted mapping of the wood industry by region as well as of planned construction of the industry facilities. It was revealed that the discussion and development of an industrialization project by the Soviet Union party-state and planning agencies in the second half of the 1920s led to increased attention to the wood industry. The sector, which enterprises were concentrated mainly in the north-west, west and central regions of the country, was set the task of increasing the volume of harvesting, export of wood and production to meet the domestic needs and the export needs of wood resources and materials. Due to weak level of development of the wood industry, the scale of these tasks required restructuring of the branch, its inclusion to the centralized economic system, the direction of large capital investments to the development of new forest areas and the construction of enterprises. It was concluded that according to the first five-year plan, the priority principles for the spatial development of the wood industry were the approach of production to forests and seaports, intrasectoral and intersectoral combining. The framework of the industry was meant to strengthen and expand by including forests to the economic turnover and building new enterprises in the European North and the Urals, where the main capital investments were sent, as well as in the Vyatka region, Transcaucasia, Siberia and the Far East.

scholarly journals Multiple controls on sediment grain properties of Peruvian coastal river basins

2017 ◽  
Author(s):  
Camille Litty ◽  
Fritz Schlunegger ◽  
Willem Viveen
Keyword(s):  
Grain Size ◽  
Drainage Basin ◽  
River Basins ◽  
Humid Climate ◽  
Sediment Properties ◽  
Peruvian Andes ◽  
Southern Group ◽  
Gravel Beds ◽  
The North ◽  
Grain Properties

Abstract. Twenty-one coastal rivers located on the western Peruvian margin were analyzed to determine the relationships between fluvial and environmental processes and sediment grain properties such as grain size, roundness and sphericity. Modern gravel beds were sampled along a north-south transect on the western side of the Peruvian Andes, and at each site the long a-axis and the intermediate b-axis of about 500 pebbles were measured. Morphometric properties such as river gradient, catchment size and discharge of each drainage basin were determined and compared against measured grain properties. Grain size data show a constant value of the D50 percentile all along the coast, but an increase in the D84 and D96 values and an increase in the ratio of the intermediate and the long axis from south to north. Our results then yield better-sorted and less spherical material in the south when compared to the north. No correlations were found between the grain size and the morphometric properties of the river basins when considering the data together. Grouping the results in a northern and southern group shows better-sorted sediments and lower D84 and D96 values for the southern group of basins. Within the two groups, correlations were found between the grain size distributions and morphometric basins properties. Our data indicates that fluvial transport is the dominant process controlling the erosion, transport and deposition of sediment in the southern basins while we propose a geomorphic control on the grain size properties in the northern basins. Sediment properties in the northern and southern basins could not be linked to differences in tectonic controls. On the other hand, the north-south trend in the grain size and in the b/a ratio seems controlled by a shift towards a more humid climate and towards a stronger El Nino impact in northern Peru. But, generally speaking, the resulting trends and differences in sediment properties seem controlled by differences in the complex geomorphic setting along the arc and forearc regions.

scholarly journals History of World and Russian Mammoth Studies

2020 ◽  
pp. 1163-1181
Author(s):  
Vladimir S. Luzan ◽  
Alexandra A. Sitnikova ◽  
Anastasia V. Kistova ◽  
Antonina I. Fil’ko ◽  
Julia S. Zamaraeva ◽  
...  
Keyword(s):  
Cultural Practices ◽  
Far East ◽  
Legal Regulation ◽  
Modern World ◽  
Russian Culture ◽  
Art Collectors ◽  
The North ◽  
Legal Provisions ◽  
The World ◽  
Historical Comparative

The article is devoted to the study of the concept of the mammoth in regulatory documents and cultural practices. The analysis of both Russian and international experience allowed to generalise the existing legal provisions regarding the regulation of mammoths, as well as to determine the role of mammoths in the world and Russian culture, including the culture of the indigenous peoples of the North, Siberia and the Far East. The methodological basis of the study is represented by the comparative analysis of sources and materials, historical-comparative and chronological methods, the historiographic method, as well as methods of philosophical and art history analysis. The study revealed the fact that in the field of legislation and legal regulation of extraction and sale of mammoth ivory in the world, the issue of the status of mammoths is raised only in connection with a discussion of the survival of rare species of elephants. Measures to prevent extermination of elephant population, encompassing a ban on trade, including trade of mammoth ivory, cause heated discussions and are controversial for craftsmen, antique dealers and art collectors. The issue of legal regulation in this area is particularly acute for the Russian Federation, due to the lack of a finalised legal and regulatory framework, both at the federal, regional and municipal levels. The image of the mammoth in the world and Russian culture is embodied in a number of visual practices. These are heraldry, animation, book graphics, sculpture and fine art. Sign and symbolic forms of the mammoth embody religious and mythological characteristics of the animal, demonstrating its significance in people’s worldview, as well as indicating of the “living” memory of it in the modern world

scholarly journals Geochemistry of Surface Sediments From the Emperor Seamount Chain, North Pacific

2021 ◽  
Vol 9 ◽  
Author(s):  
Jie Chen ◽  
Jianjun Zou ◽  
Aimei Zhu ◽  
Xuefa Shi ◽  
Dirk Nürnberg ◽  
...  
Keyword(s):  
Grain Size ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Water Depth ◽  
Surface Sediment ◽  
North Pacific ◽  
The North ◽  
Seamount Chain ◽  
The North Pacific ◽  
Emperor Seamount Chain

Investigating the composition and distribution of pelagic marine sediments is fundamental in the field of marine sedimentology. The spatial distributions of surface sediment are unclear due to limited investigation along the Emperor Seamount Chain of the North Pacific. In this study, a suite of sedimentological and geochemical proxies were analyzed, including the sediment grain size, organic carbon, CaCO3, major and rare earth elements of 50 surface sediment samples from the Emperor Seamount Chain, spanning from ∼33°N to ∼52°N. On the basis of sedimentary components, we divide them into three Zones (I, II, and III) spatially with distinct features. Sediments in Zone I (∼33°N–44°N) and Zone III (49.8°N–53°N) are dominated by clayey silt, and mainly consist of sand and silty sand in Zone II. The mean grain size of the sortable silt shows that the hydrodynamic condition in the study area is significantly stronger than that of the abyssal plain, especially at the water depth of 1,000–2,500 m. The CaCO3 contents in sediments above 4,000 m range from 20 to 84% but decrease sharply to less than 1.5% below 4,000 m, confirming that the water depth of 4,000 m is the carbonate compensation depth of the study area. Strong positive correlations between Al2O3 and Fe2O3, TiO2, MgO, and K2O (R > 0.9) in the bulk sediments indicate pronounced contributions of terrigenous materials from surrounding continent mass to the study area. Furthermore, the eolian dust makes contributions to the composition of bulk sediments as confirmed by rare earth elements. There is no significant correlation between grain size and major and minor elements, which indicates that the sedimentary grain size does not exert important effects on terrigenous components. There is significant negative δCe and positive δEu anomalies at all stations. The negative Ce anomaly mainly exists in carbonate-rich sediments, inheriting the signal of seawater. The positive Eu anomaly indicates widespread volcanism contributions to the study area from active volcanic islands arcs around the North Pacific. The relative contributions of terrestrial, volcanic, and biogenic materials vary with latitude and water depth in the study area.

scholarly journals RELATIONAL STRATEGIES AS A FACTOR OF THE INDUSTRIAL POLICY OF ENTERPRISES OF THE RUSSIAN NORTH AND ARCTIC

2020 ◽  
Vol 68 (2/2020) ◽  
pp. 83-94
Author(s):  
V. A. Leventsov ◽  
◽  
V.V. Gluhov ◽  
Keyword(s):  
Development Strategy ◽  
Industrial Policy ◽  
Far East ◽  
Economic Recession ◽  
Arctic Region ◽  
The Arctic ◽  
Industrial Enterprises ◽  
The North ◽  
In The Beginning ◽  
Relational Strategies

In the beginning of this year, key development priorities of the Arctic region of Russia were presented, which should become the basis for the Development Strategy of the Russia Arctic until 2035 prepared by the Ministry of the Far East and Arctic Development. Its main goal is to improve the level and quality of life through development of human capital, balanced spatial development, development of the economy of renewable natural resources (local production), implementation of large investmentand infrastructure projects, environmental management, etc.Accordingly, industrial enterprises of the North and the Arctic of Russia are faced with the most important task of producing competitive, innovative products, which requires consolidation of allkinds of resources that are always lacking, especially during the economic recession, low oil prices and the coronavirus pandemic.The purpose of the article is to show the role of the use of the relational strategy by industrial enterprises of the Northand the Arctic of Russia as an important factor in their industrial policy.Relational strategies of enterprises mean strategies aimed at forming their relational space as a set of links between them that create partnership advantages in order to obtain relational profit for participants.The article presents the authors’ model for forming relational strategies, consisting of five stages with their description, an algorithm for assessing relational interaction, and also considers the use of relational strategy as an important factor in the industrial policy of enterprises of the North and the Arctic of Russia.

scholarly journals Borneo – trudna przeszłość, poplątane tożsamości. Indonezyjsko-malajska konfrontacja 1963–1966

2020 ◽  
Vol 48 (2) ◽  
pp. 285-296
Author(s):  
Andrzej Połosak
Keyword(s):  
Far East ◽  
Status Quo ◽  
Colonial Period ◽  
Military Operation ◽  
East Indies ◽  
The North ◽  
The World ◽  
The Republic ◽  
Territorial Status ◽  
Commonwealth Of Nations

Borneo, the largest of the Sunda Islands, was already divided during the colonial period. Its southern part belonged to the Dutch East Indies. To the north, there were the territories of North Kalimantan, part of the British Federation of Malaya. The President of the Republic of Indonesia, Ahmed Sukarno, supported anti-colonial movements around the world. Moreover, in 1962, Indonesia launched a military operation that attached West Irian, a Dutch overseas territory in the eastern tip of New Guinea. This operation gained international support.When Great Britain revised its Far East policy in the late 1950s, London gave independence to the Federation of Malaya, known as Malaysia since that time. From then on, the country was part of the Commonwealth of Nations. President Sukarno, remembering the success of the 1962 operation, considered newly established Malaysia to be only a new incarnation of English colonial politics. In April 1963, Jakarta began invading northern Borneo to annex these lands to Indonesia. The invasion met with strong resistance from the Commonwealth of Nations. After three years of struggle, the territorial status quo from before the conflict was re-established. The invasion and its high costs shook President Sukarno’s position. As a result, he was overthrown by General Suharto and the previously pursued policy of supporting anti-colonialism ended, although Indonesia remained a member of the Non-Aligned Movement, one of whose spiritual fathers was Ahmed Sukarno.

scholarly journals The 852/3 CE Mount Churchill eruption: examining the potential climatic and societal impacts and the timing of the Medieval Climate Anomaly in the North Atlantic Region

2021 ◽  
Author(s):  
Helen Mackay ◽  
Gill Plunkett ◽  
Britta Jensen ◽  
Thomas Aubry ◽  
Christophe Corona ◽  
...  
Keyword(s):  
Tree Ring ◽  
North Atlantic ◽  
Volcanic Ash ◽  
Climate Forcing ◽  
Medieval Climate Anomaly ◽  
North Atlantic Region ◽  
Atlantic Region ◽  
Climate Anomaly ◽  
White River ◽  
The North

Abstract. The 852/3 CE eruption of Mount Churchill, Alaska, was one of the largest first millennium volcanic events, with a magnitude of 6.7 (VEI 6) and a tephra volume of 39.4–61.9 km3 (95 % confidence). The spatial extent of the ash fallout from this event is considerable and the cryptotephra (White River Ash east; WRAe) extends as far as Finland and Poland. Proximal ecosystem and societal disturbances have been linked with this eruption; however, wider eruption impacts on climate and society are unknown. Greenland ice-core records show that the eruption occurred in winter 852/3 ± 1 CE and that the eruption is associated with a relatively moderate sulfate aerosol loading, but large abundances of volcanic ash and chlorine. Here we assess the potential broader impact of this eruption using palaeoenvironmental reconstructions, historical records and climate model simulations. We also use the fortuitous timing of the 852/3 CE Churchill eruption and its extensively widespread tephra deposition of the White River Ash (east) (WRAe) to examine the climatic expression of the warm Medieval Climate Anomaly period (MCA; ca. 950–1250 CE) from precisely linked peatlands in the North Atlantic region. The reconstructed climate forcing potential of 852/3 CE Churchill eruption is moderate compared with the eruption magnitude, but tree-ring-inferred temperatures report a significant atmospheric cooling of 0.8 °C in summer 853 CE. Modelled climate scenarios also show a cooling in 853 CE, although the average magnitude of cooling is smaller (0.3 °C). The simulated spatial patterns of cooling are generally similar to those generated using the tree-ring-inferred temperature reconstructions. Tree-ring inferred cooling begins prior to the date of the eruption suggesting that natural internal climate variability may have increased the climate system’s susceptibility to further cooling. The magnitude of the reconstructed cooling could also suggest that the climate forcing potential of this eruption may be underestimated, thereby highlighting the need for greater insight into, and consideration of, the role of halogens and volcanic ash when estimating eruption climate forcing potential. Precise comparisons of palaeoenvironmental records from peatlands across North America and Europe, facilitated by the presence of the WRAe isochron, reveal no consistent MCA signal. These findings contribute to the growing body of evidence that characterizes the MCA hydroclimate as time-transgressive and heterogeneous, rather than a well-defined climatic period. The presence of the WRAe isochron also demonstrates that no long-term (multidecadal) climatic or societal impacts from the 852/3 CE Churchill eruption were identified beyond areas proximal to the eruption. Historical evidence in Europe for subsistence crises demonstrate a degree of temporal correspondence on interannual timescales, but similar events were reported outside of the eruption period and were common in the 9th century. The 852/3 CE Churchill eruption exemplifies the difficulties of identifying and confirming volcanic impacts for a single eruption, even when it is precisely dated.

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