The Block Island Times
http://block-island.villagesoup.com/p/218081

Malleable and resolute: Clay is the 'bedrock' of Block Island

By Kim Gaffett | Feb 26, 2012
Bluffs of clay and sand. Note: more erosion in sandy areas, spires of resolute clay are also called hoodoos, small holes at the upper edge are bank swallow nesting cavities.

It can be pounded and extruded, hand-built or thrown, excavated to create cozy nests, or become wind- and rain-sculpted hoodoos. Clay is Block Island’s “bedrock.” In its simplest form, clay is a substance made of very small particles of minerals such as aluminum silicate. Much smaller in grain size than the finest sand, clay, like sand, is the result of the breakdown of rocks by chemical weathering. In the case of Block Island clay, it is a material that is made from the minutest particles, and yet is the most stable material upon which this pile of glacial debris — Block Island — rests.

Clay, like any geologic substrate, is subject to weathering and erosion. Because of the structure of clay-ey minerals, clay has a high degree of plasticity and stretch. These qualities of clay, which allow beauty and function to evolve in the hands of artists, are the same qualities that give the island’s base material such strength of structure. The more pure the clay, the fewer grains of sand it contains, the more stable the base.

On Block Island, clay comes in a variety of earthly hues. Where the ground water has a high concentration of iron, the clay appears red. The clays of the southern end of the island tend to the darker, bluer part of the spectrum. The clays of Clay Head are lighter; in some places, white outcroppings of ancient cretaceous clay can be seen.

Much can be learned about the geologic source of the island’s clays and how they came to be mixed like a giant bowl of partially stirred chocolate chip cookie dough by reviewing Les Sirkin’s “Block Island Geology” (1996, Book and Tackle Shop, Watch Hill, RI). However, a stroll at the edges of the island — away from the base of the bluffs to offer safety and perspective — will conjure insights to the richness of this vertical landscape.

Depending on which island edge is explored, the seemingly expressionless gray façade may yield to the careful observer all sorts of formations. There are drizzled porcelain-like slips after a rain, paperclip swirls of clay, and outcroppings of druid-like spires of clay, also known as hoodoos. Then there are the numerous small holes that form a lattice work of bank swallow nests. And, March is the season — if you are lucky and look closely at medium-sized holes at the upper edges of a bluff — to see the face of a nesting barn owl looking back at you.

For those who prefer inland strolls to those at the island’s edges, it is a good time to recall that March, of course, technically ushers in the spring of the year, starting on March 20. To the daytime chorus of red-winged blackbirds will be added the evening ensemble of spring peepers (it has been a warm winter, so listen for ebbets early this year). The new Hoodoo moon (3/22) follows closely on the heels of the equinox, making for a vernal twilight the color of dark clay.

Go to the Ocean View Foundation Face Book page to find out more about Block Island’s bluff nesting birds or how to use “wild” clay.

The following events and Ocean View Foundation programs will help you animate March’s suddenly spring countenance.

March. 1: Winter Pot Lucks: Film & Food. 6 p.m. at the Island Library showing of Microcosmos.

March 6 & 20, at 8 a.m.: Crazy-as-a-Coot Bird Walk, call 595-7055 for location.

March 10: Listen for the first spring peeper chorus.

March 20, Vernal Equinox at 1:14 a.m. — the first day of spring.

March 22: Hoodoo New Moon.

March 24: Spring Twilight Walk & Night Sky Viewing. 7 p.m. at Hodge Preserve.

Comments (0)
If you wish to comment, please login.