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Spring 2002 Volume LVII NO. 1
Institute on Lake Superior Geology 49th Annual Meeting Southern Minnesota Well Water Turns Black New GSM Rock and Mineral Collections
2003 BOARD OF DIRECTORS Paul Martin,
President Ken Barklind, Vice
President Judy Hamilton,
Secretary Ted Chura,
Treasurer Cindy Demers Bill Farquahar Marlys Lowe Rosie O’Donovan Tom Smalec *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* Kimball
Memorial Banquet
Monday,
May 5, 2003
***LOCATION NOT YET DETERMINED***LOCATION TO BE ANNOUNCED AT THE LECTURES OR CALLSTEVE ERICKSON 651-501-9851 IN APRIL, FOR THE LOCATION Dinner
5PM, Program 7PM
Topic:
Role of Minerals in the Cultural History
of Minnesota Speaker:
Mark Jirsa, MSc Minnesota
Geological Survey *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * “One of the Ely greenstone’s strangest characteristics is the presence of large ellipsoidal shapes in the body of the rock, like eggs embedded in aspic. Geologists know that this ellipsoidal structure is typical of lava flows that solidify under water, so we have strong reason to believe that the greenstone began its existence on the floor of some long-departed Minnesota Sea.” ~
Minnesota’s Rocks and Waters: A
Geological Story, University of Minnesota Press, 1954 [Do
you think they meant ‘pillow lava’? –Ed.] GEO
QUIZ
1.Which
sea is a back-arc basin?
a)
Sea of
Cortez, b) Sea of Galilee, c) Sea of Azov, d) Sea of Japan. 2.Where
is earth’s crust the thinnest?
a)
Continental
Margins, b) Mid-Ocean ridges, c) Volcanic provinces, d) Impact craters. 3.Which
element is strongly concentrated in the earth’s crust? a)
Thorium,
b) Oxygen, c) Silicon, d) Platinum 4.What
is the most common mineral in the earth’s crust? a)Quartz,
b)Illite, c)Olivine, d)Feldspar 5.What
is the most abundant rock on earth?
a)Granite,
b)Basalt, c)Shale, d)Limestone 6.What
is the largest of earth’s lithospheric plates? a)Pacific,
b)African, c)Eurasian, d)Indian-Australian 7.What
is the waste rock around an orebody called? a)Groundmass,
b)Graywacke, c)Gangue, d)Grit (answers
are listed after “Worms with a Copper Smile”) The
remaining lectures in the 2002-2003 series will be held in the Electrical
Engineering & Computer Science Bldg. (EE Comp Sci) Room 3-210, just a few
steps N.E. of Amundson Hall.
LABS will be held at the
Minnesota Geological Survey office: ~
~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
~ ~ ~ ~ ~ ~ ~ ~ Institute on Lake Superior Geology49th Annual MeetingMay 7 – 11, 2003 The
Institute on Lake Superior Geology is a non-profit professional society with the
objectives of providing a forum for exchange of geological ideas and scientific
data and promoting better understanding of the geology of the Lake Superior
region. The 49th Annual
Meeting will be held in Iron Mountain, Michigan.
A two-day technical session will be held between pre- and post-meeting
field trips. Geology students and
interested non-professionals are welcome to attend.
For information on registration, costs, field trip topics, and more, go
to: www.ilsgeology.org Or
contact Laurel Woodruff, U.S. Geological Survey at woodruff@usgs.gov
Notes
from the Board… As
the incoming president, I thank outgoing president Steve Erickson for his hard
work and dedication during 2002. I am counting on his advice during the coming
year as I attempt to live up to the high standards he and previous presidents
have established. I also
thank those outgoing board members for their service. They are: Katy Paul,
William Robbins, Gail Marshall, and Steve Erickson. I am pleased to report that
all of these will remain active in GSM . We welcome a number of new or returning
board members: Cindy Demers, Marlys Lowe, Bill Farquhar, Ken Barklind, and Tom
Smalec. One
of the main ways we reach the public at large occurs during the Minnesota State
Fair. I doubt we have ever counted the number of people who visit our booth in
the Education Building, but it must be hundreds per day! The booth is crucial to
our program, and must be maintained and strengthened. One
of our goals this year is to update the booth, and we are very grateful to Don
and Nora Mattson for donating $1000 to help jump-start this project! If any
members have ideas on how the booth can be made better, ( more informative, more
eye-catching, and more interesting ) please contact me or Tom Schoenecker, who
presently chairs the State Fair committee. Another
vital part of what we do is the popular series of lectures and labs between
October and May each year. These are in addition to the three or four field
trips which we organize annually. The
success of these programs over the last two decades, and more, is due in large
part to the work of Rick Uthe. Rick takes ideas and topics suggested by board
members and forms them into a very coherent organized series of lectures. Kudos
to Rick, and thanks to the board for recognizing how vital he has been to GSM.
As many of you know, the 2002 board voted to give Rick an honorary lifetime
membership. At our January 13 meeting, a certificate was presented to Rick,
which said in part : “We are grateful for the vital work which he has done for
us during the last twenty-plus years, and hope he will continue to be an active
member in the future.” Thanks Rick for all you do! ~Paul
Martin, President
Southern
Minnesota Well Water Turns Black Wells
throughout southeastern Minnesota and adjacent areas of Wisconsin and Iowa
suddenly began producing black water in early November, 2002 -- an effect that
may be related to a Richter 7.9 earthquake in Alaska on November 3. While
no shaking was felt by people in the region, well drillers and environmental
monitors interviewed by the Mankato Free Press blamed the water change on
manganese released from the area’s sandstone, limestone and dolomite bedrock
by waves from the Alaskan tremor. One well-driller quoted by the newspaper said
a similar effect occurred in the region following the historic Good Friday
Alaska quake of 1964, adding that the Good Friday quake also caused some wells
in the Owatonna-Waseca area to dry up and old wells to start flowing again. Val
W. Chandler, Acting Director of the Minnesota Geological Survey, said quakes of
magnitude 8 or higher are well known to cause changes in groundwater thousands
of miles from the epicenter. “Unusually
large earthquakes produce very low-frequency oscillations or waves that travel
world-wide at the earth’s surface, and these waves can essentially squeeze
aquifers like a sponge as they pass through,” Chandler explained. “Distance
from the epicenter and the intervening structure of the crust and mantle may
also play a role in focusing this very low frequency energy, so that the effects
may not necessarily be evenly observed.” Reports
of discolored water in the Mankato area were in fact spotty and inconsistent.
While in some localities all the wells were affected, in other areas the
discoloration was found in only a few wells.
Black water was reported across a wide swath of southeastern Minnesota,
northeastern Iowa and southwestern Wisconsin, but not in the Twin Cities area. Mankato-area
residents said they normally do not see any effects in their wells from major
California quakes, and Chandler said that was because California earthquakes
aren’t as strong as those in Alaska. “Magnitude
and total energy released is probably the major factor,” Chandler said. “At
least part of the reason that no water well effects have been observed in
association with California quakes is that (thankfully) no magnitude 8 events
have occurred there in recent history.” State
officials recommended that people not drink the discolored water or give it to
livestock. Well
experts said allowing taps to run for a day or two usually cleared the black
water from home and farm systems.¨ -Tom
Smalec
NEW GSM ROCK AND MINERAL COLLECTIONS
The Ashland County, Wisconsin Bedrock Collection contains six rock specimens from outcrops in the county. It includes a fine example of an intrusive breccia, and beautiful black gabbro
Both
collections are packaged with a descriptive key in a handsome, six-compartment
polystyrene box. The
price of each collection is $10 for GSM members and $15 for non-members.
(Shipping and tax are included.) Geological Society
of MN If you have questions, Bruce can be reached by phone at this number: (952) 448-5422. Or e-mail at: bjgoetteman@worldnet.att.net
WOMEN
IN GEOLOGY:
Florence Bascom Although
Florence Bascom (1862-1945) was known as "the first woman geologist” in
this country, she was the second woman to earn a Ph.D. in geology in the
United States. (Mary Holmes earned a Ph.D. in geology from the University of
Michigan in 1888).
Bascom was the first woman hired by the U.S. Geological Survey (1896),
the first woman to present a paper before the Geological Society of Washington
(1901), the first woman elected to the Council of the Geological Society of
America (elected in 1924; no other woman was elected until after 1945), and
the first woman officer of the GSA (vice president in 1930). She was an
associate editor of the American Geologist (1896-1905) and a four-starred
geologist in the first edition of American Men and Women of Science (1906),
which meant that her colleagues regarded her as among the country's hundred
leading geologists. After joining the Bryn Mawr College faculty, Bascom
founded the college's geology department. This site became the locus of
training for the most accomplished female geologists of the early 20th
century. Bascom
was an expert in crystallography, mineralogy, and petrography. Trained by
leaders in metamorphism and crystallography including Roland Irving and
Charles Van Hise (University of Wisconsin), George Huntington Williams (Johns
Hopkins), and Victor Goldschmidt (Heidelberg, Germany), she worked in these
fields during their infancy. Her earliest contribution was her dissertation,
in which she showed petrographically that rocks previously considered
sediments were metamorphosed lava flows (Aldrich, 1990; Bascom, 1893). An
expert on crystalline rocks of the Appalachian Piedmont, she published more
than 40 research papers, including USGS Bulletins and Folios. Additionally,
she published research on Piedmont geomorphology, particularly the provenance
of surficial deposits.
This
is the text of another new geological marker erected in
2002
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