Possible refugia in the Alexander Archipelago of southeastern Alaska during the late Wisconsin glaciation

2007 ◽  
Vol 44 (2) ◽  
pp. 229-244 ◽  
Author(s):  
P E Carrara ◽  
T A Ager ◽  
J F Baichtal
Keyword(s):  
Continental Shelf ◽  
Western Hemisphere ◽  
Aerial Photographs ◽  
Western Coast ◽  
Stepping Stones ◽  
The West ◽  
Island Area ◽  
Area 6 ◽  
Early Humans ◽  
Alexander Archipelago

The interpretation of the extent of late Wisconsin glaciation in southeastern Alaska has varied between geologists and biologists. Maps and reports of the region prepared by geologists commonly indicated that late Wisconsin ice extended as a large uniform front west to the edge of the continental shelf. However, the distribution of plants and animals in the region has led many biologists to suggest that there may have been ice-free areas that served as refugia during the late Wisconsin. Based on analyses of aerial photographs, topographic maps, and bathymetric charts, in conjunction with a review of previous literature and reconnaissance fieldwork throughout the region, this study presents data supporting a limited ice extent in the Alexander Archipelago during the late Wisconsin and identifies possible ice-free areas that may have served as refugia. These areas include (1) the Fairweather Ground, (2) the Herbert Graves Island area, (3) the western coast of southern Baranof Island and adjacent continental shelf, (4) Coronation Island and the adjacent continental shelf, (5) the Warren Island area, (6) the continental shelf from west of Heceta Island to Forrester Island in the south, (7) parts of the west coast of southern Dall Island, and (8) lowland areas in southern Prince of Wales Island. The identification of these possible refugia has bearing on the recolonization of the Alexander Archipelago, as they could have served as centers of biotic dispersal upon regional deglaciation and as stepping stones for early humans with a maritime tradition entering the western hemisphere from Asia.

scholarly journals Evidence of Unknown Paleo-Tsunami Events along the Alas Strait, West Sumbawa, Indonesia

Geosciences ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 46
Author(s):  
Bachtiar W. Mutaqin ◽  
Franck Lavigne ◽  
Patrick Wassmer ◽  
Martine Trautmann ◽  
Puncak Joyontono ◽  
...  
Keyword(s):  
Radiocarbon Dating ◽  
Pyroclastic Flows ◽  
Western Coast ◽  
Eastern Shore ◽  
Tsunami Deposits ◽  
The West ◽  
Marine Deposits ◽  
Sedimentary Records ◽  
The North ◽  
Large Earthquakes

Indonesia is exposed to earthquakes, volcanic activities, and associated tsunamis. This is particularly the case for Lombok and Sumbawa Islands in West Nusa Tenggara, where evidence of tsunamis is frequently observed in its coastal sedimentary record. If the 1815 CE Tambora eruption on Sumbawa Island generated a tsunami with well-identified traces on the surrounding islands, little is known about the consequences of the 1257 CE tremendous eruption of Samalas on the neighboring islands, and especially about the possible tsunamis generated in reason of a paucity of research on coastal sedimentary records in this area. However, on Lombok Island, the eruption of the Samalas volcano produced significant volumes of pyroclastic flows that entered the sea in the North and East of the island. These phenomena must have produced a tsunami that left their traces, especially on Sumbawa Island, whose western coastline is only 14 km away from Lombok’s eastern shore. Therefore, the main goal of this study is to investigate, find evidence, and determine the age of marine-origin sediments along the shore of the Alas Strait, Indonesia. We collected and analyzed samples of coral and seashells from marine deposits identified along the west coast of Sumbawa, i.e., in Belang Island and abandoned fishponds in Kiantar Village, in order to identify the sources and the occurrence period of these deposits events. Based on the radiocarbon dating of coral and seashell samples, we concluded that none of the identified marine deposits along the western coast of Sumbawa could be related chronologically to the 1257 CE eruption of Samalas. However, possible tsunami deposits located in Belang Island and abandoned fishponds in Kiantar Village yielded 4th century CE, 9th century CE, and 17th century CE. We also conclude that past large earthquakes triggered these tsunamis since no known volcanic eruption occurred near the Alas Strait at that time that may have triggered a tsunami.

Observed variability of the West India Coastal Current on the continental shelf from 2010–2017

2021 ◽  
Vol 130 (2) ◽  
Author(s):  
Anya Chaudhuri ◽  
P Amol ◽  
D Shankar ◽  
S Mukhopadhyay ◽  
S G Aparna ◽  
...  
Keyword(s):  
Continental Shelf ◽  
Coastal Current ◽  
The West

Why no red tide was observed on the West Florida Continental Shelf in 2010

Harmful Algae ◽  
2014 ◽  
Vol 38 ◽  
pp. 119-126 ◽  
Author(s):  
Robert H. Weisberg ◽  
Lianyuan Zheng ◽  
Yonggang Liu ◽  
Chad Lembke ◽  
Jason M. Lenes ◽  
...  
Keyword(s):  
Continental Shelf ◽  
Red Tide ◽  
The West

Outer limits of the continental shelf beyond CLCS recommendations and Article 76(8) of UNCLOS: With reference to Japan’s Cabinet Order No. 302

2021 ◽  
pp. 1-19
Author(s):  
Michael Sheng-ti Gau ◽  
Si-han Zhao
Keyword(s):  
Continental Shelf ◽  
The West ◽  
Common Heritage ◽  
Common Heritage Of Mankind ◽  
Essential Questions ◽  
National Jurisdiction ◽  
The Common ◽  
United Nations Convention ◽  
Legal Consequences ◽  
The Unclos

Abstract In 2014 Japan’s Cabinet Order No. 302 declared the outer limits of its continental shelf beyond 200 nautical miles (OL) to the west and north of Oki-no-Tori Shima (Area 302). Oki-no-Tori Shima consists of two small, barren, and uninhabitable rocks in the West Pacific. The northern part of Area 302 is broader than what the 2012 recommendations of the Commission on the Limits of the Continental Shelf (CLCS) specify. A question arises whether Order No. 302 violates Article 76(8) of the United Nations Convention on the Law of the Sea (UNCLOS), which provides that the OL established by a coastal state ‘on the basis of’ the CLCS recommendations shall be final and binding. Another question is the role played by the CLCS in ‘assisting’ the coastal states to delimit their national jurisdiction so as to know where the Area (i.e., the Common Heritage of Mankind under UNCLOS Articles 1(1)(1) and 136) begins. The essential questions arising from Area 302 concern how well the UNCLOS mechanism can perform to safeguard the Common Heritage of Mankind through preventing encroachment thereupon by individual coastal states. This article looks at the context and explores the obligations implied by Article 76(8) for coastal states to ‘follow’ the recommendations in establishing the OL, with special reference to the northern part of Area 302. The article also examines legal consequences arising from a breach of these obligations.

Assessing Bypassed Hydrocarbons

2021 ◽  
Author(s):  
Stanley Oifoghe ◽  
Nora Alarcon ◽  
Lucrecia Grigoletto
Keyword(s):  
Continental Shelf ◽  
Reservoir Characterization ◽  
Gamma Ray ◽  
West African ◽  
The Novel ◽  
The West ◽  
Present Case Study ◽  
Novel Model

Abstract Hydrocarbons are bypassed in known fields. This is due to reservoir heterogeneities, complex lithology, and limitations of existing technology. This paper seeks to identify the scenarios of bypassed hydrocarbons, and to highlight how advances in reservoir characterization techniques have improved assessment of bypassed hydrocarbons. The present case study is an evaluation well drilled on the continental shelf, off the West African Coastline. The targeted thin-bedded reservoir sands are of Cenomanian age. Some technologies for assessing bypassed hydrocarbon include Gamma Ray Spectralog and Thin Bed Analysis. NMR is important for accurate reservoir characterization of thinly bedded reservoirs. The measured NMR porosity was 15pu, which is 42% of the actual porosity. Using the measured values gave a permeability of 5.3mD as against the actual permeability of 234mD. The novel model presented in this paper increased the porosity by 58% and the permeability by 4315%.

T phases from 80 Alaskan earthquakes, March 28-31, 1964

1965 ◽  
Vol 55 (1) ◽  
pp. 59-63
Author(s):  
John Northrop
Keyword(s):  
Continental Shelf ◽  
Island Area ◽  
Kodiak Island ◽  
Phase Signal ◽  
T Phase

Abstract A large T-phase signal was received at Pt. Sur, California, from the Alaskan earthquake of March 28, 1964. Additional T phases were received from 90 per cent of the 80 aftershocks studied in the Kodiak Island area. The largest T phases were received from hypocenters beneath the upper portion of the continental shelf.

scholarly journals Explosive range expansion of Eulophia graminea (Orchidaceae) in Puerto Ricio and the West Indies

Lankesteriana ◽  
2021 ◽  
Author(s):  
James D. Ackerman ◽  
Normandie González-Orellana
Keyword(s):  
Puerto Rico ◽  
Range Expansion ◽  
West Indies ◽  
First Record ◽  
The State ◽  
Western Hemisphere ◽  
The West ◽  
The Bahamas ◽  
Rapid Spread ◽  
Southern Florida

Eulophia graminea Lindley (Orchidaceae), a native orchid of tropical and subtropical Asia, was first reported in the Western Hemisphere from populations in Miami, Florida, U.S.A. where it spread rapidly through the southern part of the state. Here we report the first record of this species for Puerto Rico and sightings in the Bahamas and Cuba, reflecting the rapid spread seen in southern Florida (U.S.A).

Coleosporium ipomoeae. [Descriptions of Fungi and Bacteria].

1971 ◽  
Author(s):  
G. F. Laundon
Keyword(s):  
Sweet Potato ◽  
Geographical Distribution ◽  
West Indies ◽  
Ipomoea Batatas ◽  
Late Summer ◽  
Western Hemisphere ◽  
American Continent ◽  
Alternate Host ◽  
The West ◽  
Far North

Abstract A description is provided for Coleosporium ipomoeae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Pycnia and aecia on several species of Pinus (especially southern pines), uredial aecia and telia on several genera of the Convolvulaceae (Argyreia, Convolvulus, Ipomoea and Jacquemontia). DISEASES: Orange rust of sweet potato (Ipomoea batatas). One of the needle rusts of pines. GEOGRAPHICAL DISTRIBUTION: Probably widespread in the warmer regions of the American continent and the West Indies. Recorded on Ipomoea spp. other than sweet potato as far north as Illinois, Ohio and New Jersey. Not recorded in western states of USA or outside the western hemisphere. TRANSMISSION: Transmission of the Coleosporium rusts in Florida has been described by Weber (23: 245). Short-lived basidiospores, which rarely travel more than 1.6 km in a viable condition, infect pine needles during late summer and autumn probably through the stomata. The aeciospores formed in the spring are very resistant and can travel long distances to infect the alternate host by direct penetration of the cuticle.

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