Nunataks in Antarctica

Images ASTER and Radar of Nunataks located inside Antarctica. In some of them there were no previous maps. A Nunatak is an isolated mountain of a mountain range because it is surrounded by ice and a significant distance from a mountain range. In some cases they have never been under the ice.

 

These Nunataks are almost always associated with Blue Ice Areas, BIA, (Rivera et al, 2014a). In a BIA, there is a negative balance mass due to strong local katabatic wind generated by the presence of Nunatak that prevents or reduces local snowpack (Rivera et al, 2014b). In a BIA you may even thawing (Carrasco et al, 2000). These areas of blue ice are also interesting because meteorites can be found on their surfaces (view recommended literature).

 

 

 

 

 

Patriot Hills is a nunatak which was originally mapped by the United States Geological Survey ( USGS ) from aerial photos and ground surveys of the US Navy between 1961 and 1966. The name was given by the Advisory Committee on Antarctic Names (US - ACAN ) . In this area we have worked since 1997 and there are several interesting publications (see references) .

Edge of blue ice area between 1996 to 2008. (Rivera et al, 2014b).

 

 

Map of Liberty Hills, USGS 1966

 

 

Pirrit Hills located by the U.S. Ellsworth - Byrd Traverse Party in December 1958. Nunatak was named by the Advisory Committee on Antarctic Names (US - ACAN) in honor of John Pirrit, glaciologist who participated in the journey that wintered in Ellsworth Station. Pirrit was the leading scientist at Byrd Station in 1959.

 

 

Along with the Pirrit hills, it is the John Nunatak , is a granite nunatak examined by geologists Edward Thiel and Campbell Craddock on December 13, 1959, the United States Antarctic Research Program; in the course of a journey geophysics they were transferred by helicopter along the meridian 88° west. It was named by the Advisory Committee on Antarctic Names in honor of Orlan John F. of the U.S. Navy, who was died in a construction accident in McMurdo Sound, on November 2, 1960.

 

Nunatak Pirrit Hills fotografiado desde el aire en 2007 (Foto Andrés Rivera).

 

 

Martin Hills is a nunatak about 90 km south of Pirrit Hills. It was discovered by the U.S. Ellsworth-Byrd Traverse Party on December 10, 1958, and was baptized by the Advisory Committee on Antarctic Names in honor of Larry R. Martin, scientific leader of the Byrd Station in 1962.

 

 

 

 

Nash Hills (81°53'S 89°23'W) is located 46km northeast of Martin Hills. It was discovered by the U.S. Ellsworth - Byrd Traverse Party on 10 December 1958. It was named by the Advisory Committee on Antarctic Names in honor of Lt. Archie R. Nash of the US Navy , commanding officer of the Byrd Station in 1962.

 

 

Mount Johns is a nunatak that rises 90 meters above the ice surface, located about 86 km SW of subglacial lake CECs , west of the Heritage Range, in the Ellsworth Mountains. It was discovered by the Marie Byrd Land Traverse on January 27, 1958, and was named in honor of Robert H. Johns (1932-1958), a meteorologist who died at Byrd Station in 1958.

 

 

In 2006 during a trip to Lake Ellsworth, we installed a GPS in the Johns Mountain, -91° 16' 52.63068" Lat -79° 37' 37.26475" at a height of 2182,957 m.a.s.l. (WGS84 . EGM96) , which had functioned for 5 days.

 

 

Thiels Mountains was located first by the USARP Horlick Mountains Traverse Party, 1958-59. Thiels Mountains were studied by the USGS in 1960-61 and 1961-62. The name was assigned by the US - ACAN in honor of Dr. Edward C. Thiel , a seismologist at Ellsworth Station and the Pensacola Mountains in 1957. Thiel died along with four others in November 9, 1961 in the crash of a P2V Neptune aircraft right after takeoff from Wilkes Station.

Map of the Thiel Mountains prepared by Terry Wilson (OSU, USA) and CECs.

 

 

During the trip to the South Pole CECs in conjunction with the Instituto Geográfico Militar (IGM ) of Chile , settled in the Thiel Mountains a metal spot for GPS measurements. To do this, we had to move from the convoy

 

to reach the nunatak on skis.

 

Then we climbed the mountainside

 

The GPS receiver was installed.

 

 

References

 

Rivera A, Cawkwell F, Wendt A, Zamora R (2014): "Mapping Blue Ice Areas and Crevasses in West Antarctica Using ASTER Images, GPS and Radar.", Global Land Ice Measurements from Space, Springer-Praxis, ISBN: 978-3540798170, chapter 31, 743-757.

 

Rivera, A. R. Zamora, Uribe, J., Jaña, R., and J. Oberreuter (2014a): "Recent ice dynamic and surface mass balance of Union Glacier in the West Antarctic Ice Sheet.", The Cryosphere, 8,1445-1456, doi:10.5194/tc-8-1445-2014.

 

Rivera A, Cawkwell F, Wendt A, Zamora R (2014b): "Mapping Blue Ice Areas and Crevasses in West Antarctica Using ASTER Images, GPS and Radar.", Global Land Ice Measurements from Space, Springer-Praxis, ISBN: 978-3540798170, chapter 31, 743-757.

 

Rivera, A. , R. Zamora, C. Rada, J. Walton & S. Proctor (2010): "Glaciological investigations on Union Glacier, Ellsworth Mountains, West Antarctica.", Annals of Glaciology, 51(55).

 

Carrasco, J., Casassa, G. & Rivera, A. (2000): "A warm event at Patriot Hills, Antarctica: An ENSO related phenomen?", In: Sixth International Conference on Southern Hemisphere Meteorology and Oceanography, pp. 240-241.

 

Casassa, G., A. Rivera, C. Acuña, H. Brecher and H. Lange (2004): "Elevation change and ice flow at Horseshoe Valley, Patriot Hills, Antarctica.", Annals of Glaciology, 39, 20 - 28.

 

Wendt A., G. Casassa, A. Rivera & J. Wendt. (2009) : "Reassessment of ice mass balance at Horseshoe Valley, Antarctica.", Antarctic Science, 21(5), 505-513.

 

 

Recommended literature about Meteorites Antarctic

 

Choi, B.-G.; Lee, J.I.; Ahn, I.; Han, J.M. & Kusakabe, M. 2007: "Antarctic meteorites recovered from Thiel mountains, west Antarctica by the first Korea expedition for Antarctic meteorites." 70th Annual Meteoritical Society Meeting.


Lee et al. 2010: "Search for meteorites in the Patriot Hills area, Ellsworth mountains, west Antarctica." 61st Annual Meteoritical Society Meeting.


Lee et al. 1999. "Search for meteorites at Martin hills and Pirrit hills, Antarctica." 30th Annual Lunar and Planetary Science Conference, March 15-29, 1999, Houston, TX, abstract no. 2046