Fire precautions at Antarctic Stations
In 1946 the Falkland Islands Dependencies Survey station on Deception Island in the South Shetland Islands was completely destroyed by fire. Stores, valuable equipment and the records of many months’ work were lost. In 1948 the station at Hope Bay in Trinity Peninsula was burnt down, with the loss of two lives. In January 1952 the hut of the French Antarctic Expedition at Port-Martin in Terre Adélie was destroyed in the same way. Smaller outbreaks of fire, fortunately detected early and dealt with promptly, have been reported from other stations. Of all the difficulties which can overtake a polar expedition, the loss of its base is perhaps the most disastrous. Nevertheless, the frequency with which such losses seem to occur suggests that there are fundamental errors in the design of the huts, as well as a tendency to underestimate the danger of fire.
The Permo-Triassic Trinity Peninsula Group is a widespread, regionally metamorphosed metasedimentary sequence in northern Graham Land, Antarctica, which forms the local ‘basement’ to the mainly Jurassic–Cretaceous Antarctic Peninsula magmatic arc. The metamorphic grade, thermal evolution and pressure series of this major tectono-stratigraphical unit are largely unknown. Determining the nature of the metamorphism has relied hitherto on conventional optical identifications of the major phases, mainly in rare volcanic beds. However, diagnostic mineral parageneses are generally absent and the precise metamorphic grade is unknown or has to be inferred over large areas. Using white mica (illite) crystallinity of interbedded mudrocks, the Trinity Peninsula Group is now shown to have been pervasively altered mainly at anchizonal and epizonal grades. Conditions ranged from upper anchizonal in the northeast to thoroughly epizonal in the southwest. Outwith thermal aureoles near plutonic intrusions, the alteration temperatures ranged mainly from 250 to 325 °C, exceeding 300 °C in the highest-grade (epizone/greenschist facies) parts of the sequence. The facies series, K-white mica b cell dimension measurements and mineral phases present are characteristic of an intermediate pressure series altered under moderate geothermal gradients (<35 °C/km), corresponding to burial depths of c. 7–10 km. Unroofing and substantial erosion of the Trinity Peninsula Group took place during polyphasal vertical tectonic movements linked to the development of the magmatic arc in northern Graham Land. The geological setting of the Trinity Peninsula Group is ambiguous and could have been a foreland (or back-arc) basin or the mid- to upper levels of an accretionary prism.
There is much concern about the potential for invasive species to enter the only marine region left with no known exotics – the Southern Ocean. Attention has focused on planktonic larval travel, shipping (ballast water and hull fouling) and marine debris as transport mechanisms. There is, however, another source of transport for biota across the Polar Frontal Zone – hitchhiking on megafauna, such as seals. In this study we report the frequency and burden of barnacles Lepaa australis attached to Antarctic fur seals Arctocephalus gazella coming ashore to breed at Bird Island, South Georgia. In the austral summers of 2001/2002, 2002/2003 and 2003/2004, female fur seals with barnacles attached arrived at Bird Island in late November/early December and peaked in mid-December. About 4 % of female fur seals carried barnacles, with the mean burden being – 10 barnacles. Pedunculate barnacles seem, therefore, to be entering the Southern Ocean in large numbers every year in the South Georgia region and probably elsewhere. We also found adult barnacles attached to a macaroni penguin and (perhaps the furthest and fastest travelling marine larvae) young stages (cyprids) on the leg ring of a wandering albatross. Barnacle plates provide a hard substratum to which other fouling marine organisms can attach, and thus travel as secondary hitch-hikers. We found polychaete worms (Spirorbidae) and a bryozoan colony (Ceneporella antarctica) encrusting a stalked barnacle attached to a pycnogonan (Collosendeis scotti). We suggest that fouling hitch-hiking barnacles (on migrating megafauna) offer a considerable natural mechanism for potential colonisers of Antarctic waters, This is of particular importance at the current time given the context of strong regional warming in the Scotia Arc-Antarctic Peninsula region.
The oceanic southern margin of Gondwana, from southern South America through South Africa, West Antarctica, New Zealand (in its pre break-up position), and Victoria Land to Eastern Australia is one of the longest and longest-lived active continental margins known. It was the site of the 18,000 km Terra Australis orogen, which was initiated in Neoproterozoic times with the break-up of Rodinia, and evolved into the Mesozoic Australides. The Gondwana margin was completed, in Late Cambrian times, by closure of the Adamastor Ocean (between Brazilian and southwest African components) and the Mozambique Ocean (between East and West Gondwana), forming the Brasiliano-Pan-African mobile belts. During the Early Palaeozoic much of the southern margin was dominated by successive episodes of subduction-accretion. Eastern Australia, Northern Victoria Land and the Transantarctic Mountains were affected by one of the first of these events – the Late Cambrian Ross/Delamerian orogeny, remnants of which may be found in the Antarctic Peninsula – but also contain two accreted terranes of unknown age and origin. Similar events are recognized at the South American end of the margin, where the Cambrian Pampean orogeny occurred with dextral strike-slip along the western edge of the Río de la Plata craton, followed by an Ordovician active margin (Famatinian) associated with the collision of the Precordillera terrane. However, the central part of the margin (the Sierra de la Ventana of eastern Argentina, the Cape Fold Belt of South Africa and the Ellsworth Mountains of West Antarctica) seem to represent a passive margin during the Early Palaeozoic, with the accumulation of predominantly reworked continental sedimentary deposits (Du Toit’s ‘Samfrau Geosyncline’). In many of the outer areas, accretion and intense granitic/rhyolitic magmatism continued during the Late Palaeozoic, with collision of several small continental terranes, many of which are nevertheless of Gondwana origin: e.g., southern Patagonia and (possibly) ‘Chilenia’ in the South American–South African sectors, and the Western Province and Median Batholith terranes of New Zealand. The rhyolitic Permo–Triassic LIP of southern South America represents a Permo-Triassic switch to extensional tectonics, which continued into the Early Jurassic, and was followed by the establishment of the Andean subduction margin. Elsewhere at this time the margin largely became passive, with terrane accretion continuing in New Zealand. In the Mesozoic, the Terra Australis Orogen evolved into the accretionary Australides, with episodic orogenesis in the New Zealand, West Antarctic and South American sectors in Late Triassic–Early Jurassic and mid-Cretaceous times, even as Gondwana was breaking up.
Twinning in natural pinniped populations is often inferred from observations of suckling behavior, but this approach has been criticized because nonfilial nursing occurs at high frequencies in many seal species. Consequently, we used 9 highly polymorphic microsatellite markers to examine the parentage of 11 putative pairs of twins in Antarctic fur seals (Arctocephalus gazella) breeding at Bird Island, South Georgia. Only 3 pairs (27%) were found to be genuine twins, indicating that suckling observations are an unreliable means of identifying twins in this species. All of the twins were female; 1 pair was monozygotic and the other 2 were dizygotic. Using a strict exclusion approach, paternity was assigned to the monozygotic but not the dizygotic twins. However, likelihood tests revealed that, of the latter, 1 pair was significantly more likely to be full siblings against the null of half sibship suggesting shared paternity, whereas the other pair was more likely to be half siblings against the null of full sibship indicating probable multiple paternity. Our results provide novel insights into the reproductive ecology of fur seals and also support an earlier study showing that molecular genetic analysis can provide an effective means of validating field observations of pinniped twins.
Recent changes along the margins of the Antarctic Peninsula, such as the collapse of the Wilkins Ice Shelf, have highlighted the effects of climatic warming on the Antarctic Peninsula Ice Sheet (APIS). However, such changes must be viewed in a long-term (millennial-scale) context if we are to understand their significance for future stability of the Antarctic ice sheets. To address this, we present nine new cosmogenic Be-10 exposure ages from sites on NW Alexander Island and Rothschild Island (adjacent to the Wilkins Ice Shelf) that provide constraints on the timing of thinning of the Alexander Island ice cap since the last glacial maximum. All but one of the Be-10 ages are in the range 10.2-21.7 ka, showing a general trend of progressive ice-sheet thinning since at least 22 ka until 10 ka. The data also provide a minimum estimate (490 m) for ice-cap thickness on NW Alexander Island at the last glacial maximum. Cosmogenic He-3 ages from a rare occurrence of mantle xenoliths on Rothschild Island yield variable ages up to 46 ka, probably reflecting exhumation by periglacial processes.
Determining the drivers of movement of different life‐history stages is crucial for understanding age‐related changes in survival rates and, for marine top predators, the link between fisheries overlap and incidental mortality (bycatch), which is driving population declines in many taxa. Here, we combine individual tracking data and a movement model to investigate the environmental drivers and conservation implications of divergent movement patterns in juveniles (fledglings) and adults of a threatened seabird, the white‐chinned petrel (Procellaria aequinoctialis).
Written by Tags: 3-on-3 tournaments/Utah Jazz/Utah Jazz Summer League/Vivint Smart Home Arena May 16, 2018 /Sports News – Local Utah Jazz Announce Summer League Dates, Teams and Ticket Availability FacebookTwitterLinkedInEmailSALT LAKE CITY-Wednesday, the Utah Jazz announced the schedule of their fourth annual summer league, as well as dates, opponents and ticket information for fans.This summer, the fourth annual Utah Jazz Summer League, sponsored by America First Credit Union, University of Utah Health and the Utah Sports Commission will continue.The league runs from July 2-5 (excluding July 4) at Vivint Smart Home Arena.The Jazz welcome back the San Antonio Spurs to the league, as well as newcomers in the Atlanta Hawks and Memphis Grizzlies.Thursday, Jazz season ticket holders will have early access to tickets as general public sales start Friday at 10:00 am MDT. Lower bowl tickets are available at $8 for a one-day pass or $15 for a three-day pass. A one-day pass provides access to both games played on that day.Each team will play three games over this four-day span as part of daily doubleheaders at 5:00 and 7:00 pm MDT.Because of the 4th of July holiday, there will be no games on this day.Tickets for this six-game four-day event can be purchased online at www.utahjazzsummerleague.com, on the Utah Jazz mobile app, by calling 1-801-355-DUNK or visiting the Vivint Smart Home Arena box office during regular business hours.For the first time, the public will be able to play at the event as well as watch.The Utah Jazz 3-on-3 tournament will occur Monday July 2 on the outdoor courts at Park Place, across the street from Vivint Smart Home Arena.There will be a total of 34 divisions fans can participate in, ranging from age 9 boys and girls to under 6-foot only squads, among others.Registration for this event includes four games and a single-elimination tournament, along with a T-shirt, an admission ticket to one day of Utah Jazz Summer League action and a drawstring bag. Registration can be done online at the Jazz’s Summer League Web site.Each session of summer league play will also feature a pre-game “fan fest” at the Vivint Smart Home Arena plaza, featuring special activities and entertainment.The Jazz is also conducting basketball clinics this week for under-served youth on local community courts. Brad James
July 24, 2018 /Sports News – Local USU’s Raymond, Eberle, Named To All-MWC Preseason Team FacebookTwitterLinkedInEmailLAS VEGAS-Tuesday, at the Mountain West Conference’s Football Media Day summit, a pair of Utah State standouts were named to the preseason all-conference squad.Tight end Dax Raymond was named to the all-Mountain West preseason offensive squad and kicker Dominik Eberle was named to the all-conference special teams squad.Overall, this team consists of 25 members, 17 of whom were all-Mountain West selections last season.Eberle is among those as he was a Lou Groza award finalist last season. This award is annually given to the top placekicker in college football. He is coming off a season wherein he scored 101 points, making all 47 of his PAT attempts and connecting on 75 percent of his field goals (18 of 24).In a 61-10 win at San Jose State last September 23, Eberle set a school-record with 19 points in the game, making all four of his field goal attempts and all seven of his PAT’s.Raymond was named as honorable mention all-Mountain West by the conference’s coaches last season after netting 41 grabs for 456 yards and one score last season.The all-conference preseason QB is Boise State’s Brett Rypien and was one of eight Broncos on the all-MWC preseason roster. Tags: Brett Rypien/Dax Raymond/Dominik Eberle/USU Football Written by Brad James
Brad James FacebookTwitterLinkedInEmailBoys Basketball Tags: Clark County Chargers/Marvin “Tre” Williams/Mike Saunders/Wasatch Academy Tigers LAS VEGAS-Mike Saunders netted 18 points and the Wasatch Academy Tigers outlasted the Clark County (Nev.) Chargers 71-69 Monday in non-region boys basketball action. Marvin “Tre” Williams added 17 more points in the win for the Tigers. Non-Region Written by January 21, 2019 /Sports News – Local Prep Sports Roundup: 1/21