Using aerial photographs to locate intertidal stone fishing structures in the Prince of Wales archipelago, southeast Alaska

10.14509/1184 ◽  
1986 ◽  
Author(s):  
S. J. Langdon ◽  
D. R. Reger ◽  
Christopher Wooley
1990 ◽  
Vol 68 (3) ◽  
pp. 651-662 ◽  
Author(s):  
P. E. Hennon ◽  
E. M. Hansen ◽  
C. G. Shaw III

Alaska-cedar, Chamaecyparis nootkatensis (D. Don) Spach, has been dying in undisturbed forests throughout southeast Alaska for the last 100 years. To determine if decline spreads, boundaries of mortality at seven sites with decline were mapped using aerial photographs taken in 1927, 1948, 1965, and 1976. Mortality was present at all seven sites in 1927. The boundaries of mortality have since expanded, but not by more than 100 m beyond the 1927 limit. In ground surveys, dead Alaska-cedar trees, classified according to their degree of deterioration, were recorded in 427 plots along 39 transects. Fifty-five taxa of understory vegetation were also recorded from 280 plots along these 21 transects; an ordination was produced from their distribution that represented a gradient from bogs to sites with better drainage. Most mortality was associated with bog and semibog sites. Alaska-cedar has a disproportionate level of mortality (65% of basal area dead) relative to other conifers. Local spread of cedar decline occurred along this gradient, as plots with more recently killed cedar trees had high average ordination scores (better drainage) and plots with cedars killed long ago had low average scores (boggy). Snags that probably date from the onset of extensive mortality were relatively common (at least 8% of all snags) on all 23 sites where intensive mortality was surveyed on the ground. As all sites with mortality that we investigated throughout southeast Alaska have these snags, decline does not appear to have spread to new sites since its onset. Although decline is relatively species specific and has patterns of local spread, the spread of mortality is along a specific, preexisting ecological gradient. These results, and the apparent lack of any site to site spread in the last 100 years, suggest that Alaska-cedar decline is not caused by some biotic agent.


1986 ◽  
Vol 13 (1) ◽  
pp. 78-85 ◽  
Author(s):  
Heather F James

Summary A two week excavation in two areas around the Scheduled Monument known as Montfode Mount confirmed the existence of the arcs of two outer concentric ditches noted on aerial photographs and an inner ditch at the base of the motte. There was no stratigraphical relationship between the outer ditches and the motte, and the excavation did not provide dating evidence for any of these features. While allowing for the fact that the outer ditches may be Medieval in date the excavator suggests that the ditches formed part of the defenses of a promontory fort of prehistoric date. In the light of recent work the interpretation of the mound as a motte is also discussed.


2003 ◽  
Author(s):  
Michael H. McClellan ◽  
Terry Brock ◽  
James F. Baichtal

2000 ◽  
Author(s):  
Michael H. McClellan ◽  
Douglas N. Swanston ◽  
Paul E. Hennon ◽  
Robert L. Deal ◽  
Toni L. de Santo ◽  
...  

Author(s):  
D., A., L., A. Putri

Tectonic activity in an area could result in various impacts such as changes in elevation, level of slope percentages, river flow patterns and systems, and the formation of geological structures both locally and regionally, which will form a new landscape. The tectonic activity also affects the stratigraphic sequences of the area. Therefore, it is necessary to study morphotectonic or landscape forms that are influenced by active tectonic activities, both those occur recently and in the past. These geological results help provide information of the potential of natural resources in and around Tanjung Bungo area. Morphological data are based on three main aspects including morphogenesis, morphometry, and morphography. The data are collected in two ways, the first is field survey by directly observing and taking field data such as measuring geological structures, rock positions, and outcrop profiles. The second way is to interpret them through Digital Elevation Model (DEM) and aerial photographs by analyzing river flow patterns and lineament analysis. The field measurement data are processed using WinTensor, Dips, and SedLog Software. The supporting data such as Topographic Maps, Morphological Elevation Maps, Slope Maps, Flow Pattern Maps, and Lineament Maps are based on DEM data and are processed using ArcGis Software 10.6.1 and PCI Geomatica. Morphotectonically, the Tanjung Bungo area is at a moderate to high-class level of tectonic activity taken place actively resulted in several joints, faults, and folds. The formation of geological structures has affected the morphological conditions of the area as seen from the development of steep slopes, structural flow patterns such as radial, rectangular, and dendritic, as well as illustrated by rough surface relief in Tanjung Bungo area. This area has the potential for oil and gas resources as indicated by the Telisa Formation, consisting of calcareous silts rich in planktonic and benthonic fossils, which may be source rocks and its contact with the Menggala Formation which is braided river system deposits that could be good reservoirs. Further research needs to be done since current research is only an interpretation of surface data. Current natural resources being exploited in Tanjung Bungo region are coals. The coals have thicknesses of 5-7 cm and are classified as bituminous coals.


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