Exposure Hill Formation

The Exposure Hill Formation occurs at the base of the sheet-like lava flows of Kirkpatrick Basalt that form the Mesa Range of northern Victoria Land and on nearby nunataks most of which are located in the Rennick graben in Fig. 12.6. The deposits of breccia and related pyroclastic rocks occur at Exposure Hill at the southern end of Gair Mesa and at Mt. Fazio and Scarab Peak on Tobin Mesa as well as on Mt. Carson adjacent to the Aeronaut Glacier in Fig. 12.7. hi addition, Elliot et al. (1986a) described a deposit of breccia on Agate Peak located about 26 km east of the northern tip of Pain Mesa (Fig. 12.6). 

The thickness of the Exposure Formation varies locally between 10 and 150 m. It is composed of breccia containing clasts of altered basalt, vesicular basalt, dolerite, sandstone, and beds of lapiUi tuff, tuff, and tuffaceous ripple-marked sandstone (Elliot et al. 1986a Wbmer 1992 Roland and Wbmer 1996). 

Section Peak Formation. Therefore, the breccias of the Exposure Hill Formation could have formed as a result of phreatomagmatic explosions in the subsurface like those that produced the Mawson Diamictite in the Coombs Hills (White and McClintock 2001). 

The age of Exposure Hill Formation is constrained by its stratigraphic position to be older than 

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The Exposure Hill Formation of northern Victoria Land occupies the same stratigraphic position as the Mawson Formation in the Allan and Coombs hills of southern Victoria Land. Both formations are composed of volcanic breccias and related pyroclastic rocks that formed at the start of the eruption of the Kirkpatrick Basalt and the intrusion of sills of the Ferrar Dolerite of the Middle Jurassic Ferrar Group which is the subject of Chapter 12. 

Goswami IN, Sinha N, Murty SVS, Mohapatra RK, Qement Cl (1997) Nuclear tracks rmd fight noble gases in AUem Hills 84001 Pre-atmospheiic size, fall characteristics, cosmic ray exposure duration and formation age. Meteorit Planet Sci 32 91-96 Gounelle M, Zolensky ME (2001) A terrestrial origin for the sulfate veins in CIl chondrites. Meteorit Planet Sci 36 1321-1329... 

Asbestos is ubiquitous in the environment. More than 40% of the land area of the United States is composed of minerals which may contain asbestos. Fortunately, the actual formation of great amounts of asbestos is relatively rare. Nonetheless, there are locations in which environmental exposure can be severe such as in the Serpentine Hills of California. 

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