Publications

Three species of alcids, Common and Thick-billed murres (Uria aalge and U. lomvia) and the Razorbill (Alca torda), have post-hatching developmental patterns intermediate to precocial and semi-precocial modes (Sealy 1973). The young leave their cliff nest sites at about one quarter of adult weight and complete their growth at sea. At departure, an event here loosely referred to as...

Seabirds were observed between Alaska and Hawaii along 158°W longitude from 24 October to 6 November 1976. Their distributions and abundances corresponded remarkably well to oceanographic regions. Indices of seabird density dropped in a series of plateaus from 44 birds/km2 in the Alaska Current System to less than 1 bird/km2 in subtropic waters. Northern distribution records were found...

Porphyry type sulfide systems on the central Alaska Peninsula occupy a transition zone between the Aleutian island magmatic arc and the continental magmatic arc of southern Alaska. Mineralization occurs associated with early and late Tertiary magmatic centers emplaced through a thick section of Mesozoic continental margin clastic sedimentary rocks. The systems are of the molybdenum-rich...

No abstract available.

Band recoveries (N = 315) over 26 years (1951-77) and three surveys of seabird bycatch in inshore fishing nets (1972, 1980-81) indicate that there has been a substantial net-mortality of Atlantic Puffins (Fratercula arctica) and Common Murres (Uria aalge) in Newfoundland coastal waters for the past 2 decades. Offshore (e.g. Grand Banks) gill-netting is limited, but some data suggest that...

In the late 1960s and early 1970s, a high net-mortality of seabirds, particularly Thick-billed Murres (Uria lomvia), was associated with the west Greenland salmon fishery. Since 1972, the domestic fishery has been controlled by quotas and fishery opening dates and non-Greenlandic offshore drift-net fishery was phased out in 1975. These restrictions probably resulted in a substantial...

The Alaska radiometric age file of the Branch of Alaskan Geology is a computer-based compilation of radiometric dates from the state of Alaska and the western parts of the Yukon Territory and British Columbia. More than 1800 age determinations from over 250 references have been entered in the file. References date back to 1958 and include both published and unpublished sources. The file...

The recently completed aeromagnetic survey of the Chignik and Sutwik Island quadrangles, on the Alaska Peninsula, is one of the most detailed systematic surveys ever made across a modern "volcanic arc" setting where both Holocene volcanic edifices and older volcanic centers occur (fig. 54).

Results of recent potassium-argon age studies in the Chignik region, Alaska, (Wilson, 1980; Wilson and others, 1982) have suggested a distinct episodicity in igneous activity during Tertiary time. To date work on the Aleutian magmatic arc indicates that plutonic activity took place along the present outer Pacific margin and in the northern Alaska-Aleutian Range batholith (Reed and...

No abstract available.

Geochemical reconnaissance studies in the Bristol Bay, Ugashik, and Karluk quadrangles were completed with collection and analyses of more than 1,200 stream-sediment and heavy mineral-concentrate samples during 1979 and 1980. At least two areas of possible metallic mineral occurrence have been delineated by results of the analyses, geologic fieldwork, and data provided by Bear Creek...

Early and preliminary results of potassiumargon dating work on samples from 12 sites in the Ugashik quadrangle indicate a continuation of the geologic trends seen in the Chignik and Sutwik Island quadrangles to the south (Wilson, 1980). Tertiary volcanic and hypabyssal rocks apparently fall into two age groups: early Tertiary-late Eocene to earliest Miocene and late Tertiary and...