Integrative Natural History of Minnesota's North Shore, Part GFSP-B: A Closer Look at a Building Stone and Its Colorful Colonizer | Gooseberry Falls State Park
(Updated on June 9, 2025)
Looking at a portion of one building stone on the Lakeview Shelter. This structure overlooks the Superior shore on the southern side of the Gooseberry River mouth.
This close-up gives us a good opportunity to really examine both the Beaver Bay Complex Gabbro building stone and its colorful colonizer, the aptly named Elegant Sunburst Lichen (Rusavskia elegans). See the previous post's description for more on the rock's origin in the Midcontinent Rift.
Being an igneous intrusive rock, the iron-rich ferrogabbro shown here cooled and solidified from its parent magma more slowly than its overlying North Shore Volcanic Group basalt. Though the surface here is weathered, you can still make out individual crystals large enough to be seen without magnification.
And one more lichenological note: Rusavskia elegans was formerly known as Xanthoria elegans. It remains in the family Teloschistaceae.
To see the other photos and descriptions of this series, visit
my Integrative Natural History of Minnesota's North Shore album.
Integrative Natural History of Minnesota's North Shore, Part GFSP-B: A Closer Look at a Building Stone and Its Colorful Colonizer | Gooseberry Falls State Park
(Updated on June 9, 2025)
Looking at a portion of one building stone on the Lakeview Shelter. This structure overlooks the Superior shore on the southern side of the Gooseberry River mouth.
This close-up gives us a good opportunity to really examine both the Beaver Bay Complex Gabbro building stone and its colorful colonizer, the aptly named Elegant Sunburst Lichen (Rusavskia elegans). See the previous post's description for more on the rock's origin in the Midcontinent Rift.
Being an igneous intrusive rock, the iron-rich ferrogabbro shown here cooled and solidified from its parent magma more slowly than its overlying North Shore Volcanic Group basalt. Though the surface here is weathered, you can still make out individual crystals large enough to be seen without magnification.
And one more lichenological note: Rusavskia elegans was formerly known as Xanthoria elegans. It remains in the family Teloschistaceae.
To see the other photos and descriptions of this series, visit
my Integrative Natural History of Minnesota's North Shore album.