Properties, age, and significance of dunes near Snow Water Lake, Elko County, Nevada

2017 ◽  
Vol 87 (1) ◽  
pp. 24-36 ◽  
Author(s):  
Jeffrey S. Munroe ◽  
Andrew L. Gorin ◽  
Noah N. Stone ◽  
William H. Amidon
Keyword(s):  
Climatic Conditions ◽  
Luminescence Dating ◽  
The North ◽  
Water Lake ◽  
Infrared Stimulated Luminescence ◽  
Silty Loam ◽  
Snow Water ◽  
Climatic Regime ◽  
Moisture Sensitive ◽  
North And South

AbstractDunes adjacent to the Snow Water Lake playa in Elko County of northeastern Nevada rise up to ~10 m above the playa surface in seven distinct clusters. The dunes are composed of tan silty loam containing calcite, quartz, plagioclase, and dioctahedral clay. Abundances of trace elements, along with relative proportions of quartz and calcite, are distinct between dunes along the north and south sides of the playa, reflecting proximity to streams draining different lithologies in the neighboring mountains. Luminescence (optically stimulated luminescence and infrared-stimulated luminescence) dating of dune crest samples demonstrates that the last episode of dune accumulation occurred in the mid-eighteenth century. Moisture-sensitive tree ring records from a nearby site indicate that dune accumulation coincided with an interval of below-average precipitation immediately following a very wet decade. This sequence is consistent with models requiring wetter climatic conditions to move coarse sediment onto a playa surface, followed by dune building under drier conditions. Younger luminescence ages from a sand-dominated unit exposed in an arroyo cut through the dunes may reflect a wetter, more erosive climatic regime ca. AD 1800. The Snow Water Lake dunes are currently eroding, signaling a reduction in the amount of sediment reaching the playa.

scholarly journals Evidence from the Rio Bayo valley on the extent of the North Patagonian Icefield during the Late Pleistocene–Holocene Transition

2006 ◽  
Vol 65 (1) ◽  
pp. 70-77 ◽  
Author(s):  
Neil F. Glasser ◽  
Stephan Harrison ◽  
Susan Ivy-Ochs ◽  
Geoffrey A.T. Duller ◽  
Peter W. Kubik
Keyword(s):  
Late Pleistocene ◽  
Climatic Conditions ◽  
Optically Stimulated Luminescence ◽  
Luminescence Dating ◽  
Age Dating ◽  
Outlet Glacier ◽  
Geomorphological Mapping ◽  
Cosmogenic Nuclide ◽  
The North ◽  
Exposure Age

AbstractThis paper presents data on the extent of the North Patagonian Icefield during the Late Pleistocene–Holocene transition using cosmogenic nuclide exposure age and optically stimulated luminescence dating. We describe geomorphological and geochronological evidence for glacier extent in one of the major valleys surrounding the North Patagonian Icefield, the Rio Bayo valley. Geomorphological mapping provides evidence for the existence of two types of former ice masses in this area: (i) a large outlet glacier of the North Patagonian Icefield, which occupied the main Rio Bayo valley, and (ii) a number of small glaciers that developed in cirques on the slopes of the mountains surrounding the valley. Cosmogenic nuclide exposure-age dating of two erratic boulders on the floor of the Rio Bayo valley indicate that the outlet glacier of the icefield withdrew from the Rio Bayo valley after 10,900 ± 1000 yr (the mean of two boulders dated to 11,400 ± 900 yr and 10,500 ± 800 yr). Single-grain optically stimulated luminescence (OSL) dating of an ice-contact landform constructed against this glacier indicates that this ice mass remained in the valley until at least 9700 ± 700 yr. The agreement between the two independent dating techniques (OSL and cosmogenic nuclide exposure age dating) increases our confidence in these age estimates. A date obtained from a boulder on a cirque moraine above the main valley indicates that glaciers advanced in cirques surrounding the icefield some time around 12,500 ± 900 yr. This evidence for an expanded North Patagonian Icefield between 10,900 ± 1000 yr and 9700 ± 700 yr implies cold climatic conditions dominated at this time.

scholarly journals Biological Security of Polish Military Contingents Outside the Country

2019 ◽  
Vol 5 (2) ◽  
pp. 62-67
Author(s):  
Beata Osiak
Keyword(s):  
Significant Role ◽  
Environmental Conditions ◽  
Climatic Conditions ◽  
Cultural Barriers ◽  
Tropical Diseases ◽  
Biological Safety ◽  
The North ◽  
The World ◽  
North And South ◽  
The Eu

Polish soldiers have been participating in peacekeeping and stabilization missions around the world for several decades under the auspices of the UN, OSCE, NATO and the EU. They were first sent to Korea in 1953 to oversee a ceasefire between the North and South Koreas. Since then, nearly 70,000 Polish troops have taken part in 58 peace and humanitarian multinational missions on different continents (SKMP ONZ, 2019), which required from them great skills to cooperate with soldiers from other countries, to overcome cultural barriers,  as well as adaptation to difficult, often completely different than in Europe, climatic conditions,  and to create a system of safeguards and procedures against dangerous tropical diseases. Due to these reasons, biological safety, i.e.,  medical, sanitary-hygienic, and anti-epidemic security of the contingent, plays a significant role in every mission because it allows the soldiers and civilian personnel stay healthy in an unfavorable and different climate and environmental conditions.

scholarly journals RECONSTRUCTIONS OF HYDROLOGIC VARIABLES IN THE NORTH PLATTE RIVER BASIN

2020 ◽  
Vol 6 (2) ◽  
pp. 59-71
Author(s):  
Sally Rose Anderson ◽  
Amanda Bowen ◽  
Glenn Tootle ◽  
Abdoul Oubeidillah
Keyword(s):  
Soil Moisture ◽  
River Basin ◽  
Snow Water Equivalent ◽  
Platte River ◽  
The North ◽  
Hydrologic Variability ◽  
Snow Water ◽  
Moisture Sensitive ◽  
Platte River Basin

Reconstructions of hydrologic variables are commonly created using tree-ring chronologies (TRCs) to generate information about historic climate and potential future variability. This study used TRCs to reconstruct annual streamflow, April 1st Snow Water Equivalent (SWE), and soil moisture in the North Platte River Basin (NPRB). Stepwise linear regression was performed to determine which of the 55 moisture sensitive TRCs were the best predictors of hydrologic variation. The regressions explained 63% of the variability in streamflow, 55% of the variability in SWE, and 66% of the variability in soil moisture. This study then maximized the overlapping period of records which resulted in a decrease in the percent of variability explained but indicated that the regression models were stable for long reconstruction periods. This study successfully reconstructed all three hydrologic variables for NPRB to 1438 or earlier. Temporal wet and dry periods for streamflow and SWE were closely aligned while soil moisture did not follow similar temporal patterns. This was likely due to a natural “lag” between soil moisture and streamflow / SWE given soil moisture tends to retain antecedent signals. The availability of reconstructed hydrologic data in NPRB allows for a better understanding of the long-term hydrologic variability in the region.

Preliminary results of the study on the reasons of the Hai Hau erosion phenomenon

2007 ◽  
Vol 29 (3) ◽  
pp. 415-426
Author(s):  
Pham Van Ninh ◽  
Phan Ngoc Vinh ◽  
Nguyen Manh Hung ◽  
Dinh Van Manh
Keyword(s):  
Mathematical Modeling ◽  
Historical Data ◽  
Middle Part ◽  
Red River ◽  
Erosion Process ◽  
Red River Delta ◽  
The North ◽  
Severe Erosion ◽  
North And South ◽  
Very High

Overall the evolution process of the Red River Delta based on the maps and historical data resulted in a fact that before the 20th century all the Nam Dinh coastline was attributed to accumulation. Then started the erosion process at Xuan Thuydistrict and from the period of 1935 - 1965 the most severe erosion was contributed in the stretch from Ha Lan to Hai Trieu, 1965 - 1990 in Hai Chinh - Hai Hoa, 1990 - 2005 in the middle part of Hai Chinh - Hai Thinh (Hai Hau district). The adjoining stretches were suffered from not severe erosion. At the same time, the Ba Lat mouth is advanced to the sea and to the North and South direction by the time with a very high rate.The first task of the mathematical modeling of coastal line evolution of Hai Hau is to evaluate this important historical marked periods e. g. to model the coastal line at the periods before 1900, 1935 - 1965; 1965 - 1990; 1990 - 2005. The tasks is very complicated and time and working labors consuming.In the paper, the primarily results of the above mentioned simulations (as waves, currents, sediments transports and bottom - coastal lines evolution) has been shown. Based on the obtained results, there is a strong correlation between the protrusion magnitude and the southward moving of the erosion areas.

Peculiarities of the course of the postpartum period in domestic reindeer females, its morphophysiology and behavioral reactions in the North-East of Russia (Republic of Sakha)

2020 ◽  
pp. 99-105
Author(s):  
V. Fedorov ◽  
E. Sleptsov ◽  
K. Plemyashov
Keyword(s):  
Postpartum Period ◽  
Reproductive Function ◽  
Complex Problem ◽  
Climatic Conditions ◽  
Taiga Zone ◽  
Behavioral Reactions ◽  
North East ◽  
The North ◽  
The Republic ◽  
Mountain Taiga

A growth in the number of deer and an increase in their productivity are closely related to the solution of the complex problem of reproduction and rational use of deer females. Significant damage to reindeer husbandry is caused by the barrenness of northern domestic deer, the level of which has been quite high in recent years. So, in the Republic of Sakha, on 01.01.2020, the number of domesticated reindeer was 152,068, of which female deer and heifers — 71,818, offspring per 100 females — 59, business yield amounted to 52 fawns per 100 females. The causes of infertility are very diverse, as the natural and climatic conditions of the breeding zones have a significant influence on the reproductive function of reindeer. In Yakutia, the main population of northern domestic deer is bred in mountain taiga and tundra natural-climatic zones, so there are about 55 thousand deer in the mountain taiga zone and more than 65 thousand deer in the tundra zone. In this regard, the study of the peculiarities of the postpartum period course in domestic reindeer females, its morphophysiology, and behavioral reactions depending on the natural and climatic conditions of breeding is of great importance.

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