The link between geology and wine may be strong, but according to some, the
link between geology and beer is even stronger.
“The most
direct influence of geology is with beer — which one rarely hears about,”
says Alex Maltman, a geologist at the University of Wales, Aberystwyth. “The
link comes about because beer is mostly water, and for most brewers this is
obtained from a local aquifer.”
Geologist John Hickenlooper,
now mayor of Denver, and his partner, a geophysicist, founded the Wynkoop Brewing
Company in Denver in 1988. Geology and beer share a long history, rich in scientific
discoveries and cultural connections. Image courtesy Wynkoop Brewing Company.
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Web exclusive:
Today, some brewers are trying to revive old methods of brewing, some
of which involve geology. An ancient process call Steinbier uses hot rocks
to boil the wort. Sugars in the wort then caramelize on the stone, adding
a different flavor to the beer. The ideal rock is one that can withstand
thermal changes and one that will not react chemically with the acidic
wort, usually granite. The method was revived in 1982 in Germany by the
Franz Joseph Sailer Brewery's production of their Rauchenfels Steinbier. SEP |
The brewing process is water intensive: First, malted barley and other cereals
are steeped in hot water, a process called mashing. The resulting liquid, called
the wort, is then boiled with hops, the female flowers of a member of the cannabis
family responsible for the bitter and aromatic components of beer. Last, the
concoction is fermented with yeast.
Breweries have traditionally been located on rivers, but, contrary to popular
belief, brewers typically used surface river water only for running and cooling
machinery, and drew their brewing water from groundwater wells or springs. “The
geology of the aquifer directly influences the pH and concentrations of certain
key ions,” says Rick Saltus, a geophysicist at the U.S. Geological Survey
(USGS) in Denver, Colo. And water geochemistry, Maltman says, “affects
both the brewing process — and hence the most suitable beer styles —
and the taste of the beer.”
The fact that certain beer styles are best brewed from certain types of water
was discovered by trial and error long before an understanding of water chemistry
developed. Monks in Burton-on-Trent, Great Britain, began brewing beer in the
6th century from well water drawn from the evaporite-rich Permo-Triassic sandstones
outside of town. Such hard water, high in calcium and sulfate, brings out the
bitterness typical of classic ales and helps prevent spoilage, which allowed
for long-distance transport, even as far as India, and the eventual rise of
a new variety — the India pale ale.
In contrast, the ionically depleted, soft water of Plzen in the Czech Republic
resulted in the development of the light, clean-tasting lager now known as a
pilsner which became the standard for hoppy, pale, dry lagers. (A lager, from
the German word lagern meaning “to store,” is a beer that goes through
a period of cold storage as part of the brewing process. Before the advent of
refrigeration, brewers took advantage of caves for lagering purposes.)
Porter was first developed in 18th century London from water high in calcium
and carbonate and low in sulfate and chloride. It was exported to Ireland where,
in 1759, a Dublin brewer named Arthur Guinness began to make a thicker, or stouter,
porter from local waters with similar chemistry. His brew became known worldwide
as stout.
According to Maltman, there is possibly some merit to the pub legend that Guinness
brewed in Dublin tastes different than Guinness brewed in London. Although the
brewing waters of both are high in carbonate, the limestone source rocks of
the Irish brewing waters are Lower Carboniferous, while those of the London
brew are Cretaceous Chalk, which results in slightly different levels of magnesium,
chlorine, sodium and potassium and accounts for the sweeter taste of the London
variety.
With the elucidation of the water chemistries behind different styles of beer
and technological advances in the science of brewing (called zymurgy), pure
Rocky Mountain spring water can now be made anywhere. “Now it is easy to
brew any type of beer with a soft water supply because one can merely add the
necessary components to water,” says consulting geologist and amateur brewer
John Wakabayashi of Hayward, Calif. However, “to brew a Czech-style pilsner
with a hard water supply takes a bit more doing,” he says, because adding
ions is easier than removing them.
Although water chemistry strongly determines the type of beer that can be made
from it, Wakabayashi says that it isn’t the most important influence on
a brew’s flavor. “It is my opinion that flavor characteristics of
malted barley, hop varieties and different fermentation flavor profiles imparted
by different yeast strains are far greater influences in beer flavor than brewing
water,” he says.
But here too, geology plays a role. Maltman says that the regions most suitable
for growing barley and hops are fertile, well-drained volcanic soils. More than
70 percent of American hops are now grown on the deep alluvial soils of the
Yakima and Willamette Valleys of Washington and Oregon, which are derived from
the nearby Cascade volcanic uplands.
The association between geology and beer, however, goes both ways, says Saltus,
who along with USGS colleague David V. Smith has suggested the topic of geology
and beer for an evening session at the upcoming annual Geological Society of
America meeting in Denver. “I think that it is also true that beer has
had an influence on geology, and especially field geology,” Saltus says.
“Geologic mapping is a type of storytelling, rooted in observation, but
requiring a lot of imagination and creativity. In many cases the crafting of
these stories involves the kind of free-wheeling sharing of ideas and analogies
that comes about after a few beers.”
Wakabayashi agrees. “The strongest connection between geology and beer,”
he says, “is the love that geologists have of beer.”
Sara Pratt
Geotimes contributing writer
Tantalum is a metal that is critical to the United States because of its defense-related
applications in aircraft, missiles and radio communications. It is ductile,
easily fabricated, highly resistant to corrosion by acids, a good conductor
of heat and electricity, and has a high melting point. Tantalum’s first
commercial usage was as filament material in incandescent electric lamps in
the early 1900s.
Currently, more than 60 percent of total tantalum consumed is in the electronics
industry, mainly in the form of tantalum metal powder used in the manufacture
of tantalum capacitors. Major end uses for tantalum capacitors include automotive
electronics, pagers, personal computers and portable telephones.
Alloyed with other metals, tantalum is also used in making carbide tools for
metalworking equipment and in the production of superalloys for aircraft engine
components. In 2003, estimated overall U.S. consumption of all tantalum materials
was about 500 tons. World mine production in 2003 was about 1,230 tons.
The principal source of tantalum is a series of minerals that contain columbium
(niobium), iron, manganese and tantalum oxides. There has been no significant
U.S. tantalum mining since 1959. U.S. tantalum resources are of low grade, some
are mineralogically complex, and most are not commercially recoverable. With
no tantalum mining industry, the United States must import all its tantalum
source materials for processing.
On a worldwide basis, identified resources of tantalum are considered adequate
to meet projected needs. Tantalum mineral production comes mostly from mining
operations in Australia, Brazil and Canada, as well as from smaller mining operations
in some African countries. Australia, which is the largest producer, accounts
for more than 60 percent of the world’s annual requirements for tantalum
mineral concentrates. In 2003, Australia accounted for about 56 percent of total
U.S. tantalum imports. Tantalum is also obtained from low- and high-grade tantalum-bearing
tin slags, which are byproducts from tin smelting, principally from Asia, Australia
and Brazil. However, the overall importance of these byproducts has decreased,
with the exception of accumulated inventories, owing to the downsizing of the
tin industry during the 1980s.
To ensure supplies of tantalum during an emergency, various tantalum materials
have been purchased for the National Defense Stockpile (NDS). At year-end 2003,
the NDS tantalum inventory consisted of about 628 tons of tantalum contained
in tantalum materials valued at about $34 million, all of which was authorized
for sale by the Defense Logistics Agency.
The price for tantalum products is affected most by events in the supply of
and demand for tantalum minerals. Faced with runaway tantalum mineral prices
during the late 1970s through 1980, processors were forced to pass along a large
part of the price increases to end users, which had the effect of a decrease
in the use of tantalum.
Because of escalating tantalum prices, consumers began to substitute alternative
products, to decrease tantalum content in products and to increase recycling.
In the consumer electronics sector, some circuits were redesigned, and tantalum
was replaced primarily with aluminum-bearing electronic components.
Tantalum was recycled mostly from new scrap that was generated during the manufacture
of tantalum-related electronic components. Recycled tantalum also comes from
new and old scrap products of tantalum-containing cemented carbides and superalloys.
Detailed data on the quantities of tantalum recycled in the United States in
2003 are not available, but recycled tantalum may compose as much as 20 percent
of consumption. Substitutes, such as aluminum, rhenium, titanium, tungsten and
zirconium, can be used in place of tantalum, but are usually used at the expense
of either performance or economics.
For more information on tantalum, visit the
USGS Minerals Division online.
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For many geologists, an ice-cold
Rolling Rock beer at the end of a long day in the field is a fine tradition.
What better way to wind down than to drink a beer that honors a geologic
setting? First made in 1939 and named in honor of the smooth-pebbled streams
that flow off the Alleghany Mountains, Rolling Rock stood out for many
years as one of the only brews with a geologically themed name.