Granodiorite Boulder from Antarctica - Menlo Park, California
Posted by: Groundspeak Premium Member Volcanoguy
N 37° 27.345 W 122° 10.201
10S E 573406 N 4145755
Granitic boulder from Antarctica at the USGS Campus in Menlo Park, California.
Waymark Code: WMADGP
Location: California, United States
Date Posted: 12/31/2010
Published By:Groundspeak Regular Member lenron
Views: 4

This boulder from Antarctica is one example of a series of large blocks of rocks from various locations, which are on display around the USGS Campus in Menlo Park. There is a self-guided tour of the campus available at the visitor center.
Text of Sign: “This boulder was collected in the Ross Sea during the 1984 research cruise of the USGS ship S.P. Lee. It was dredged at a depth of 2000 meters (6,500 feet) from the flank of Iselin Bank, the northern extension of a wide basement ridge 100 kilometers (60 miles) wide. It is reportedly one of the largest samples yet collected from the Antarctic continent. The composition of granodiorite is similar to plutonic rock located in the Transantarctica Mountains situated onshore 700 kilometers (450 miles) to the west. It is, however, believed to have been carved from granitic rocks on Iselin Bank itself. If so, it represents a fragment of the slab of continental crust left behind during the break-apart of Antarctica, Australia and New Zealand about 80 million years ago.”

Type of Display: Geological

Visit Instructions:
When posting a visit, please provide at least one photo - including yourself in one of of the photos, your GPSr, or a photo different than the default photo.
Also, please provide your impression of the specimen or display.
Search for... Google Map
Google Maps
Bing Maps
Nearest Waymarks
Nearest Rock and Mineral Displays
Nearest Geocaches
Create a scavenger hunt using this waymark as the center point
Recent Visits/Logs:
Date Logged Log  
Volcanoguy visited Granodiorite Boulder from Antarctica - Menlo Park, California 12/15/2010 Volcanoguy visited it