Quaternary geology of the Nenana River valley and adjacent parts of the Alaska Range; Engineering geology along part of the Alaska Railroad

1958 ◽  
Author(s):  
Clyde Wahrhaftig ◽  
R.F. Black
Keyword(s):  
Engineering Geology ◽  
River Valley ◽  
Quaternary Geology ◽  
Alaska Range

Testing the perspectives for discovery of the Paleolithic sites in the northern portion of the Ob river valley: Quaternary geology, paleogeography, and geomorphology

2019 ◽  
Vol 17 ◽  
pp. 109-116
Author(s):  
Ivan D. Zolnikov ◽  
Anton V. Vybornov ◽  
Alexander V. Postnov ◽  
Andrey G. Rybalko ◽  
Andrei A. Kartoziia
Keyword(s):  
River Valley ◽  
Quaternary Geology ◽  
Ob River ◽  
Northern Portion

Moraine chronosequence of the Donnelly Dome region, Alaska

2010 ◽  
Vol 74 (1) ◽  
pp. 63-72 ◽  
Author(s):  
A. Matmon ◽  
J.P. Briner ◽  
G. Carver ◽  
P. Bierman ◽  
R.C. Finkel
Keyword(s):  
Late Pleistocene ◽  
Age Distribution ◽  
River Valley ◽  
Pleistocene Glaciation ◽  
Alaska Range ◽  
Depositional Processes ◽  
Reference Locality ◽  
Northern Alaska ◽  
Exposure Ages

AbstractWe present 10Be exposure ages from moraines in the Delta River Valley, a reference locality for Pleistocene glaciation in the northern Alaska Range. The ages are from material deposited during the Delta and Donnelly glaciations, which have been correlated with MIS 6 and 2, respectively. 10Be chronology indicates that at least part of the Delta moraine stabilized during MIS 4/3, and that the Donnelly moraine stabilized ∼ 17 ka. These ages correlate with other dates from the Alaska Range and other regions in Alaska, suggesting synchronicity across Beringia during pulses of late Pleistocene glaciation. Several sample types were collected: boulders, single clasts, and gravel samples (amalgamated small clasts) from around boulders as well as from surfaces devoid of boulders. Comparing 10Be ages of these sample types reveals the influence of pre/post-depositional processes, including boulder erosion, boulder exhumation, and moraine surface lowering. These processes occur continuously but seem to accelerate during and immediately after successive glacial episodes. The result is a multi-peak age distribution indicating that once a moraine persists through subsequent glaciations the chronological significance of cosmogenic ages derived from samples collected on that moraine diminishes significantly. The absence of Holocene ages implies relatively minor exhumation and/or weathering since 12 ka.

scholarly journals The Initial Period of the Investigation of the Relief and Landscape of the Oka River Valley (the 19th Century — the 1940s)

2021 ◽  
pp. 130-139
Author(s):  
А.Ю. Воробьев
Keyword(s):  
19Th Century ◽  
Initial Period ◽  
River Valley ◽  
Quaternary Geology ◽  
Moscow Region ◽  
The South ◽  
River Terraces ◽  
Vladimir Region ◽  
The 19Th Century

Рассматриваются изданные с середины XIX века до 1940-х годов работы, посвященные физико-географическим исследованиям в пределах долины средней Оки в Рязанской области, юго-востока Московской области и юга Владимирской области. Отмечен повышенный интерес к вопросам четвертичной геологии и распределения высот в террасовом комплексе долины. Выделены достижения в области разработки вопросов типизации археологических памятников и геоморфологического районирования. Обозначены тенденции, существовавшие в распределении акцентов в физико-географических исследованиях региона за период с середины XIX века по 40-е годы ХХ столетия. Определены главные методологические черты исследовательской работы, осуществлявшейся ведущими и региональными научными физико-географическими школами в обозначенный период и предметом которой были современное состояние долинных геокомплексов средней Оки и их облик в древности. The article treats research works published in the period between the mid 19th century and the 1940s and devoted to the investigation of the Oka river valley in the Ryazan region, the southeast of the Moscow region and the south of the Vladimir region. The article underlines that the issues of quaternary geology and architecture of river terraces have been investigated by many researchers. The article analyzes works devoted to the classification of archeological and geomorphological structures. It investigates tendencies associated with geographic research of the region during the mid 19th century – the 1940s. It identifies major methodological characteristics of the research of the architecture of the Oka river valley performed by leading and local geographic societies.

The Stampede tephra: a middle Pleistocene marker bed in glacial and eolian deposits of central Alaska

1991 ◽  
Vol 28 (7) ◽  
pp. 991-1002 ◽  
Author(s):  
James E. Begét ◽  
Mary Keskinen
Keyword(s):  
River Valley ◽  
Middle Pleistocene ◽  
Alaska Range ◽  
Multiple Fault ◽  
Eolian Sediments ◽  
Eolian Deposits ◽  
Quaternary Glaciations

A deformed block of silt incorporated in a push moraine of the Lignite Creek drift of the Nenana River valley in central Alaska contains the 10 cm thick Stampede tephra. The silt block and tephra are folded, sheared, and cut by multiple fault planes and appear to have been entrained by a glacier and deformed by glaciotectonic processes while frozen. The Stampede tephra is also found in a paleosol preserved within a sequence of eolian sediments near the Tanana River some 175 km to the northeast, allowing direct tephrochronologic correlations between the depositional record of Quaternary glaciations in the Alaska Range and eolian sediments in unglaciated central Alaska. The Lignite Creek drift predates deposits of the late Wisconsin Riley Creek and penultimate Healy glaciations but postdates the Stampede tephra, indicating that it dates to the middle Quaternary, and is not part of the Tertiary Nenana Gravel Formation.

Variations in late Quaternary wind intensity from grain-size partitioning of loess deposits in the Nenana River Valley, Alaska

2017 ◽  
Vol 87 (2) ◽  
pp. 258-274 ◽  
Author(s):  
Lyndsay M. DiPietro ◽  
Steven G. Driese ◽  
Tyler W. Nelson ◽  
Jane L. Harvill
Keyword(s):  
Grain Size ◽  
Late Quaternary ◽  
Archaeological Site ◽  
Coarse Sand ◽  
River Valley ◽  
Weibull Function ◽  
Katabatic Winds ◽  
Alaska Range ◽  
Holocene Thermal Maximum ◽  
Wind Intensity

AbstractA high-resolution column of 57 loess samples was collected from the Dry Creek archaeological site in the Nenana River Valley in central Alaska. Numerical grain-size partitioning using a mixed Weibull function was performed on grain-size distributions to obtain a reconstructed record of wind intensity over the last ~15,000 yr. Two grain-size components were identified, one with a mode in the coarse silt range (C1) and the other ranging from medium to very coarse sand (C2). C1 dominates most samples and records regional northerly winds carrying sediment from the Nenana River. These winds were strong during cold intervals, namely, the Carlo Creek glacial readvance (14.2–14 ka), a late Holocene Neoglacial period (4.2–2.7 ka), and recent glacier expansion; weak during the Allerød (14–13.3 ka) and Younger Dryas (12.9–11.7 ka); and variable during the Holocene thermal maximum (11.4–9.4 ka). Deposition of C2 was episodic and represents locally derived sand deposited by southerly katabatic winds from the Alaska Range. These katabatic winds occurred mainly prior to 12 ka and after 4 ka. This study shows that numerical grain-size partitioning is a powerful tool for reconstructing paleoclimate and that it can be successfully applied to Alaskan loess.

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