Geologic evidence for late quaternary movement on the Clan Alpine Fault, west-central Nevada : Trench logs, scarp profiles, location maps, and sample and soil descriptions

2005 ◽  
Author(s):  
Michael N. Machette ◽  
Kathleen M. Haller ◽  
Cal A. Ruleman ◽  
Shannon Mahan ◽  
Koji Okumura
Keyword(s):  
Late Quaternary ◽  
Alpine Fault ◽  
West Central

The late Quaternary history of Greely Fiord and its tributaries, west-central Ellesmere Island

1990 ◽  
Vol 27 (2) ◽  
pp. 255-270 ◽  
Author(s):  
John England
Keyword(s):  
Sea Level ◽  
Late Quaternary ◽  
Sensu Stricto ◽  
Ellesmere Island ◽  
Relative Sea Level ◽  
Ice Caps ◽  
Last Glaciation ◽  
West Central ◽  
Grounding Line ◽  
Minimum Age

Moraines and meltwater channels mark the limit of the last glaciation that interfingered with the sea around the perimeter of Greely Fiord and its tributaries. The extent of this ice advance was dictated predominantly by its proximity to the sea. Consequently, the large tidewater glaciers at the fiord heads today were so constrained by calving that they advanced only 5–10 km. Similarly, grounding-line deposits from widespread plateau ice caps also terminate just below marine limit. The most extensive outlet glaciers, which advanced 20–35 km beyond present margins, are simply those that had access to the most extensive terrain above marine limit, i.e., the northwest margin of the Agassiz Ice Cap.Forty-one new 14C dates are presented. The onset of the last ice advance must predate marine shells collected from sediments overlying a former grounding line when sea level was 122 m higher than present. At this site, the lowermost shells collected from glaciomarine silts dated 38 070 ± 410 BP, whereas a surface sample 13 m above them dated 22 900 ± 190 BP. Although both dates may be minimum estimates, they are nonetheless associated with an ice margin that retreated only a few kilometres by 7850 BP, suggesting the maintenance of the glacioisostatic loading (and relative sea level) during the interim. Nearby, shells in growth position overlying bedrock confirm that relative sea level was > 83 m asl by 38 010 ± 410 BP (minimum age). These marine deposits lie outside the last ice limit and are not overlain by glacigenic sediments.Distal to the last ice limit, Greely Fiord was occupied by the full glacial sea, whose limit is marked by discontinuous beaches and wave-cut benches. The full glacial sea rises from 116 m north of Greely Fiord to a maximum elevation of 148 m bordering its south shore from which it descends to 112 m asl near the head of Cañon Fiord. Numerous 14C dates on shells collected within 8 m of marine limit show that the full glacial sea remained stable from at least 8400 to 7400 BP. Several other shell samples collected ~20 m below marine limit are much older (> 22 000 BP). The position of relative sea level between ca. 8000 and > 22 000 BP is uncertain; however, stratigraphic evidence for an intervening regression has not been found.The modest extent of the last ice limit encircling Greely Fiord, together with its occupancy by the full glacial sea, is fully compatible with the paleogeography previously reported from northeast Ellesmere Island and northwest Greenland. Furthermore, this data base provides a reinterpretation of a 500 km transect previously reported along west-central Ellesmere Island to the south and affirms that the Innuitian Ice Sheet, defined sensu stricto for the last glaciation, is supplanted by the full glacial Innuitian Sea, which penetrated the Queen Elizabeth Islands, constraining the last ice limit.

scholarly journals Late Quaternary evolution of the Alpine Fault Zone at Paringa, South Westland, New Zealand

1994 ◽  
Vol 37 (1) ◽  
pp. 49-58 ◽  
Author(s):  
Guy D. H. Simpson ◽  
Alan F. Cooper ◽  
Richard J. Norris
Keyword(s):  
New Zealand ◽  
Fault Zone ◽  
Late Quaternary ◽  
Alpine Fault

Late Quaternary Intraplate Deformation Defined by the Las Chacras Fault Zone, West‐Central Argentina

Tectonics ◽  
2021 ◽  
Vol 40 (4) ◽  
Author(s):  
Jeremy M. Rimando ◽  
Lindsay M. Schoenbohm ◽  
Gustavo Ortiz ◽  
Patricia Alvarado ◽  
Agostina Venerdini ◽  
...  
Keyword(s):  
Fault Zone ◽  
Late Quaternary ◽  
Intraplate Deformation ◽  
Central Argentina ◽  
West Central

Late Quaternary Vegetation and Climatic History of the Long Valley Area, West-Central Idaho, U.S.A.

2001 ◽  
Vol 56 (1) ◽  
pp. 103-111 ◽  
Author(s):  
James P. Doerner ◽  
Paul E. Carrara
Keyword(s):  
Late Quaternary ◽  
Regional Climate ◽  
Pine Forest ◽  
West Central ◽  
Long Valley ◽  
Pollen Rain ◽  
History Of ◽  
Climatic History ◽  
Valley Area ◽  
Central Idaho

AbstractPaleoenvironmental data, including pollen and sediment analyses, radiocarbon ages, and tephra identifications of a core recovered from a fen, provide a ca. 16,500 14C yr B.P. record of late Quaternary vegetation and climate change in the Long Valley area of west-central Idaho. The fen was deglaciated prior to ca. 16,500 14C yr B.P., after which the pollen rain was dominated by Artemisia, suggesting that a cold, dry climate prevailed until ca. 12,200 14C yr B.P. From ca. 12,200 to 9750 14C yr B.P. temperatures gradually increased and a cool, moist climate similar to the present prevailed. During this period a closed spruce–pine forest surrounded the fen. This cool, moist climate was briefly interrupted by a dry and/or cold interval between ca. 10,800 and 10,400 14C yr B.P. that may be related to the Younger Dryas climatic oscillation. From ca. 9750 to 3200 14C yr B.P. the regional climate was significantly warmer and drier than at present and an open pine forest dominated the area around the fen. Maximum aridity occurred after the deposition of the Mazama tephra (ca. 6730 14C yr B.P.). After 3200 14C yr B.P. regional cooling brought cool, moist conditions to the area; the establishment of the modern montane forest around the fen and present-day cool and moist climate began at ca. 2000 14C yr B.P.

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