Pre-Mississippian stratigraphy and provenance of the North Slope of Arctic Alaska II: Basinal rocks of the northeastern Brooks Range and their significance in circum-Arctic evolution

2019 ◽  
Author(s):  
Justin V. Strauss ◽  
Benjamin G. Johnson ◽  
Maurice Colpron ◽  
Lyle L. Nelson ◽  
Joshua L. Perez ◽  
...  
Keyword(s):  
North Slope ◽  
Brooks Range ◽  
The North ◽  
Arctic Alaska

Kinematic and subsidence modeling of the north-central Brooks Range and North Slope of Alaska

1995 ◽  
Author(s):  
Frances E. Cole ◽  
K.J. Bird ◽  
Jaime Toro ◽  
Francois Roure ◽  
D.G. Howell
Keyword(s):  
North Slope ◽  
Brooks Range ◽  
North Central ◽  
The North ◽  
North Slope Of Alaska

Neoproterozoic glaciation on a carbonate platform margin in Arctic Alaska and the origin of the North Slope subterrane

2009 ◽  
Vol 121 (3-4) ◽  
pp. 448-473 ◽  
Author(s):  
Francis A. Macdonald ◽  
William C. McClelland ◽  
Daniel P. Schrag ◽  
Winston P. Macdonald
Keyword(s):  
Carbonate Platform ◽  
North Slope ◽  
The North ◽  
Arctic Alaska ◽  
Platform Margin ◽  
Neoproterozoic Glaciation ◽  
Carbonate Platform Margin

scholarly journals Revised distribution of an Alaskan endemic, the Alaska Hare (Lepus othus), with implications for taxonomy, biogeography, and climate change

2016 ◽  
Vol 2 (2) ◽  
pp. 50-66 ◽  
Author(s):  
Michelle M. Cason ◽  
Andrew P. Baltensperger ◽  
Travis L. Booms ◽  
John J. Burns ◽  
Link E. Olson
Keyword(s):  
North America ◽  
Current Distribution ◽  
Taxonomic Status ◽  
Range Shift ◽  
North Slope ◽  
Distribution Model ◽  
Oil And Gas Development ◽  
Brooks Range ◽  
Terrestrial Mammals ◽  
The North

The Alaska Hare (Lepus othus Merriam 1900) is the largest lagomorph in North America but remains one of the most poorly studied terrestrial mammals on the continent. Its current distribution is restricted to western Alaska south of the Brooks Range, but historical accounts from north of the Brooks Range (the North Slope) have led to confusion over its past, present, and predicted future distributions. To determine if L. othus occurs or historically occurred on the North Slope, we surveyed museum collections, vetted observational accounts, and produced a spatial distribution model based on the resulting georeferenced records. We located a historic specimen long presumed lost that suggests the occurrence of L. othus on the North Slope as recently as the late 1800s. We also uncovered evidence of L. othus and (or) Mountain Hare (Lepus timidus Linnaeus 1758) on several islands in the Bering Sea, raising the possibility of recurring gene flow between these closely related species across seasonal ice connecting Asia and North America. While our results paint a more complete picture of the current distribution of L. othus, persistent uncertainties surrounding its taxonomic status and potential northward range shift onto lands reserved for oil and gas development call for additional study.

U-Pb and oxygen isotope characteristics of Timanian- and Caledonian-age detrital zircons from the Brooks Range, Arctic Alaska, USA

2019 ◽  
Vol 131 (9-10) ◽  
pp. 1459-1479
Author(s):  
F.A. Robinson ◽  
J. Toro ◽  
V. Pease
Keyword(s):  
Detrital Zircon ◽  
Crustal Contamination ◽  
Progressive Increase ◽  
Detrital Zircons ◽  
Rich Region ◽  
Brooks Range ◽  
The North ◽  
Arctic Alaska ◽  
Formed Part ◽  
Amerasian Basin

AbstractThe Devonian connection between the Brooks Range of Alaska, USA, with the continental margin of Arctic Canada and its subsequent Jurassic–Cretaceous counterclockwise rotation to form the Amerasian Basin, is a highly debated topic in Arctic tectonics. This resource-rich region was assembled from terranes that formed part of Laurentia or Baltica, or were juvenile oceanic arcs in the early Paleozoic that were brought together during Caledonian Orogenesis and the subsequent collision that formed Pangea (Uralide Orogeny). Elements of these orogens, as well as older ones, are predicted to occur in the Brooks Range of Arctic Alaska. This study presents the first combined zircon U-Pb and oxygen data from six Brooks Range metasedimentary units with assumed Neoproterozoic to Devonian ages. Three distinct detrital zircon patterns are identified in these units: (1) those with Neoproterozoic maximum depositional ages characteristic of the Timanide Orogen of northern Baltica and adjacent parts of Siberia, (2) an almost unimodal Siluro–Ordovician (443.5 ± 2.3 Ma) detrital zircon population consistent with the oceanic Apoon arc believed to have existed off shore of northern Laurentia and to have accreted to the North Slope subterrane during the Caledonian event, and (3) those with Middle Devonian maximum depositional ages consistent with post-accretion extension during the final (Scandian) phase of Caledonian Orogenesis. Oxygen isotopes from the same zircons reveal minor to significant crustal contamination with approximately two thirds (n = 255/405) having δ18O values >5.9‰ (above the mantle field of 5.3 ± 0.6‰). Pattern 1 units exhibit a progressive increase in δ18O values throughout the Proterozoic (5.99 to 9.29‰) indicative of increasing crustal growth and Timanide age zircons yield average δ18O values of 7.18 ± 0.64‰ (n = 26) suggestive of more crustal influence than Caledonian age zircons, possibly reflecting northern Baltica signatures. The unimodal population in Pattern 2 yields average δ18O values of 5.49 ± 0.66‰ (n = 17) and 6.02 ± 0.27‰ (n = 23) prior to and during, respectively, the main Caledonian event and suggest derivation from Devonian juvenile arc sources possibly representing the initiation of the collision between Laurentia and Baltica. Similar to Pattern 1, the δ18O values associated with Pattern 3 show a progressive increase in δ18O values throughout the Proterozoic (5.00 to 9.39‰). However, Pattern 3 also exhibits a distinct juvenile fingerprint (6.13 ± 0.24‰, n = 51) during the main Caledonian event and a slight increase to 7.12 ± 1‰ (n = 7) in post-Caledonian zircons possibly suggest correlating with a post-accretion phase in which proximally sourced zircon-bearing detritus was deposited in extension-related basins marking the joining of Laurentia and Baltica.

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