May 2020 Volume 74, No. 2 Promoting public interest and educational support in the geological sciences

THE GEOLOGICAL SOCIETY OF MINNESOTA News From the President’s Desk… Volunteer Before I write this article each quarter, I look back at what I wrote one year earlier, as I typically cover similar topics each year. I did that again before writing this, but more opportunities, for nostalgia, as so much has unexpectedly changed over the past few months. field trips, As you already know, the last four lectures of the spring schedule, starting March 16, were canceled due to the risks associated with the COVID-19 pandemic. At the time, lectures, and the Board considered carefully before cancelling; but in the end, our decision was confirmed as Minnesota went on general lockdown shortly after we made our public service, decision. We had four very fine lectures scheduled for Spring 2020, and Program Chair Steve Erickson hopes to reschedule those. For the ten lectures in 2019-2020, we had a since 1938 total attendance of 863 persons, for an average attendance of 86. This is just below our average in the low 90s for the past few years. We had an especially good turnout of 131 for The Midcontinent Rift System - Almost an Ocean. Over the 10 lectures, 63 persons (7%) identified themselves as attending for the first time. This shows we are making our presence known to non-members. As usual, the most common reasons given by first- timers are recommendations by friends & relatives, visiting our booth at the State Fair and finding us online. Steve is working on the 2020-2021 schedule, although we can’t yet know how that will play out. As of this writing, Steve has scheduled about half the speakers for next year, included all of whom were cancelled from this year. The tentative plan is that the 2020- 2021 lecture program will start with a talk by Greg Brick on Underground Minnesota at the Fall Banquet at U Garden Restaurant on Monday, September 21 and continue every other Monday until December 14, before the year-end break and resumption in late January. The full lecture schedule will appear in the August Newsletter and will be available on our web site earlier. If you have an idea for a lecture or lab, or know of a possible presenter, contact Steve with the information. That said, having the banquet depends on it being safe to gather, and on the restaurant still being in business. Live lectures depend on the U of Minnesota being open for business. At this time, these are all unknown. If we cannot have live lectures, we will look into presenting them using Zoom or some other videoconference platform, until the situation improves. You will be informed as soon as we learn more. Related to U Garden: When we cancelled the Spring Banquet, the Board decided to pay U Garden the normal banquet fee as a gesture of support for a business which has served us very well over the past years as a banquet venue and place to gather. GSM President, Dave Wilhelm The COVID-19 crisis has put our planning for the State Fair on hold, as it is uncertain if gsmn.org Upper photograph, Mark Ryan

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the State Fair will even be held this year. And if it is held, will we feel safe staffing a booth to talk to hundreds of fairgoers? As this situation becomes Inside this issue: clearer, I will let you know via e-mail.

Presidents message 1 COVID-19 will also curtail or eliminate

Board Membership 2 GSM field trips this year.Kate Clover is investigating a group hike sometime New Members 3 this summer along the Mississippi Member spotlight 3 River near downtown St. Paul followed Notes from the Past 4 by a walk through the old Upper travel in Minnesota, check out our Gemstone Lab-Macalester 4 Landing neighborhood to explore the array of over 70 information markers Flowing Sand 5 Platteville limestone and how it was describing interesting geology Hawai’i Volcano trip 6 used as a building stone in houses throughout our state. To find markers New Zealand-Mercury Bay 9 dating to the 1870s. We think with where you will travel, follow the link Minnesota’s Geology Markers on the New Ordovician fossil 10 family radios, we could do it with proper social distancing. Once we select home page of the GSM web site. Curved Sioux Quartzite 11 a date, we’ll send out an email notice. Rebecca Galkiewicz and Alan Smith Geological sites in 13 At the current time, Joe Newberg and I have developed a great tool for finding Chronostratigraphic chart 15 have no other ideas for field trips that these markers. You can visit them while N.H. Winchell biography 16 would work given the restrictions of keeping a social distance from others social distancing, but if you think of who might visit at the same time. something else that you feel might Stay healthy and stay informed as we work, let me know and we will negotiate this new way of living and investigate. learning So, what does GSM have to offer in the Dave Wilhelm age of COVID-19? First, we have this GSM Newsletter, which editorsKate Clover, Officers: Visit us on Mark Ryan, Harvey Thorleifson and Dave Wilhelm, President Facebook! Rich Lively have put together as usual. Deborah Naffziger, Vice President (I never thought the phrase “as usual” Dave Kelso, Treasurer would sound so good!) I have Dave Kelso, Secretary previewed bits of this Newsletter prior Board Members: Wolf Bielefeld; Frank to its publication, and look forward to Janezich; Dave Kelso; Roxy Knuttila; reading all of it when you do. Thank Deborah Naffziger, Joe Newberg; Patrick you, editors! Pfundstein; Theresa Tweet; John Second, I and other members have been Westgaard; Dave Wilhelm looking for interesting seminars and Editors: Kate Clover; Mark Ryan; articles that can be accessed online. I Harvey Thorleifson; Rich Lively will continue to send you e-mails as I Programs/Lectures/Labs: Steve Erickson become aware of these. If you learn of something that our members might State Fair: vacant from the GSM archives: like, let me know and I’ll pass it on. Video Library: David Wilhelm St. Louis River, Jay Cooke Theresa Tweet, Mark Ryan, and I also Webmaster: Alan Smith State Park, 1939 post articles related to geology on the Membership: Joanie Furlong GSM Facebook page as we find them, Field Trips: David Wilhelm; Joe so check that out occasionally; the link Newberg is on Page 2. Outreach: Joel Renner Third, a few of us have been meeting socially via Zoom at 7 PM Mondays. If Geological Markers: Rebecca you would like to join a session, drop Galkiewicz me a line at [email protected], Lecture Recording: Joe Wright and I’ll send you a link and Web Site: gsmn.org instructions. I have included a photo The Geological Society of Minnesota is a Kate Clover took of a recent “meeting.” 501(c)3 nonprofit organization. Fourth, if your summer plans include GSM Mail Address: Send all GSM gsmn.org 2

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membership dues, change of address cards, and GSM Member Spotlight—Mary Kay Arthur renewals to: Joanie Furlong, GSM Membership Chair, P.O. Box 141065, , MN 55414‐6065 Membership categories and dues: Student (full time) $10 Individual $20 Family $30 Sustaining $50 Supporting $100 Guarantor $250 Individual and Family memberships can be renewed for 1, 2, or 3 years. Members donating at the Sustaining, Supporting or Guarantor levels will have their names highlighted in the GSM membership directory. GSM News: The purpose of this newsletter is to inform members and friends of activities of interest to the Geological Society of Minnesota. GSM News is published four times a year during the months of February, May, August and November. Newsletter contributions welcome: GSM enthusiasts: Have you seen interesting geology while traveling? If so, please consider sharing your Mary Kay Arthur on a whale-watching cruise; Kona, Hawaii, experiences with others through our GSM Newsletter. photo by Dave Wilhelm Write a short article, add a photo or two and send it in. Deadline for submission is the first of the month before In the mid-1990’s, I took a canoeing class with Gail the publication date. Send your story to newsletter Marshall, GSM’s long-time membership chair and editor: Kate Clover, [email protected] Thank you in tireless recruiter. Her persistence won me over, and I’ve advance. been an enthusiastic GSM participant and lecture GSM Board Membership: attendee whenever I am in Minneapolis. My favorite The GSM Board consists of members who have a special lectures are those that discuss basic principles, for interest in advancing the goals of the society, including example, “How was Minnesota compiled.” I enjoy talks lectures, field trips, and community outreach. The Board from Minnesota engineers and researchers who share currently has ten members, and our bylaws limit terms their research project such as Ray Rogers discussing his to four years to encourage turnover, and a change of dinosaur digs in Montana, and Barr Engineering perspectives and ideas. explaining their efforts to site the bases for wind turbines. Lectures on soil structure helped me The Board meets quarterly, on the second Thursdays of understand the vitality of Midwest farm country. I’m February, May, August, and November, or on a always amazed and heartened by the willingness of different date if conflicts arise. Meetings are from 7-9 professional geologists to bring their knowledge to our PM at the Minnesota Geological Survey at 2609 W. meetings. Territorial Rd, St. Paul, MN 55114. My personal contributions to GSM are slim; however, I Board meetings are open to all GSM members. If you organized the summer 2018 GSM field trip to Thunder are a new or long-time member and Board membership Bay, Ontario. (The rocks don’t stop at the border). And I is of interest to you, please consider attending a make great chocolate brownies for cookie break. I love meeting. If you have a topic you would like the Board to all the friends I have made through GSM, and I love consider, please contact Dave Wilhelm, Monday the Monday night lectures. [email protected] Winter months find me escaping to warm places. I New GSM Members: wander around in my pickup camper enjoying the nooks and crannies of America’s out-of-doors. There is Gary Miland Dukes, Minneapolis great hiking, paddling, birding, plant ID and just plain John Fierst, Rochester snooping around in this country’s wild places. For in- your-face geology there is nothing like Big Bend in Texas (volcanic mountain, desert, river, and both the Appalachian and Laramide orogeny) or the Kiabab Trail to the bottom of the Grand Canyon.

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NOTES FROM THE PAST enables our Outreach presenters the ability to access, store, share and From the Summer 1982 Edition of the GSM News glean ideas from Members who attended our spring banquet were previous privileged to hear an outline of a timely study Dr. presentations. Robert Sloan is preparing on the origin of mammals. More recently, he With drawings, pictures and charts as well as samples donated fossils of fossils, he gave us a summary of the enormous collected from an amount of evidence of the many species which evolved Iowa field trip from reptiles, some of which became mammals. The for GSM event was a fitting climax to our lecture series. to donate at the recent Minnesota We are eagerly awaiting Sloan’s account of the search The lab included hands-on activities and for our ultimate ancestors as the scientific refutation of Earth Science demonstrations by geology students the claims being propounded by the Creationists. Teachers Special thanks to Mark and Dorothy Jefferys, social Association conference, MESTA. As a sign of our activities chairs for their efforts in arranging the appreciation for this ongoing relationship, the GSM banquet. Fifty-nine people attended and several more presented Jeff with a GSM hammer created by came later for the talk. Estwing Manufacturing, another exceptional organization. The Geological Society of Minnesota Lab at Jeff began the Lab with an overview of birthstone Macalester College – February 2020 gemology and the minerals that comprise each gem. He showed slides of the processed stones, as well as On Saturday morning, February 8th, on the grounds of examples of the Macalester College Campus, Geology Laboratory many of the Supervisor Jeff same stones in Thole hosted a the rough. Then Lab entitled, “An using Micros X- Exploration of Ray Fluorescence the Mineralogy (Micro XRF) and and SEM/EDS Geochemistry of spectrometers, Gemstones.” The Jeff identified the Macalester Lab is composition and always a popular element lecture, and this Macalester student Alex demonstrates how a distribution of Refractive Index (RI) is collected from a gem Jeff provides an overview of birthstone year’s event was assorted jewelry gemology no different and and stones furnished by GSM participants. was well However, then things got different. Jeff invited three attended. students to show some of the different aspects of their The lecture began with a form of GSM appreciation for work with gemstones. Jeff Thole. Since 2010, Macalester College and Jeff have Alex, a sophomore geology major, showed how a shared the Olin-Rice Science Center Lab and its refractometer worked. This device measures the way specimens and light reacts (change in velocity) while passing through instruments with different minerals. Using a liquid with a refractive index the Geological (RI) value of 1.81, a stone is placed flat-side down on top Society of of the liquid, then the refractometer is closed and a Minnesota. He also monochromatic recruited excellent light source is student assistants turned on. Then over the years to as you look help with the labs. through the Jeff has been a major eyepiece, you can Jeff demonstrates the use of remote part of GSM’s directly read the analysis tools to determine gem Student RI of the gem on composition Outreach program the scale. Natural which delivers the and synthetic science of Geology to 1st through 8th grade metro-area minerals and classrooms. He also set up and maintains the cloud site glass have a Mac graduate Emma Thole demonstrates "Team Drive: Geological Society of Minnesota” which gemstone faceting gsmn.org 4

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specific range of hike many times. RIs, and this Typically, we see the information helps decomposed to determine the sandstone piled along mineralogy and the base of the bluffs, authenticity of but with spring thaw specific stones. and water seeping Emma, Jeff’s over the hillside, the daughter and loose sandstone grains recent Macalester on the hillside had Grinding a gemstone on the Facetron mixed with the water faceting machine graduate, was on hand to and had formed demonstrate gemstone faceting using a “Facetron” beautiful flow faceting machine. She also demonstrated some new patterns. And in some software, Gem Cut Studio that she uses to help with the areas, the water- gem cutting process. Emma added that she likes doing saturated sand was St. Peter Sandstone bluff between projects that take a lot of time and patience. On the actually flowing as we Lilydale and Mendota, Mn other hand, she noted, “grinding can be very tedious; watched. In other the smallest mistake can have you redoing your work.” areas, the Clara, a junior Geology major, has a collection of sand had gemstones. She explained her work on collecting micro- already XRF spectra on the roughly 350 specimens in her dried out collection. The resulting ‘empirical database’ will be enough to used to compare micro-XRF spectra to the more familiar erase the x-ray spectra collected from the SEM/EDS. The resulting delicate database will hopefully one day be a resource for future flow Macalester mineralogy students. patterns. This year’s lab proved to be interesting and engaging I wondered, with the students taking on lead roles, both for our what does benefit and the benefit of future Macalester geology this flowing students. sand feel like? I touched Intricate patterns created by flowing sand gently. It felt “soft,” and my finger left a small impression; and the feeling reminded me of touching a cookie that was baking to determine its doneness. After I touched it, the little divot re-filled with water and plumped back up! Having had lots of Photomicrograph of decomposed St. experience grabbing Peter Sandstone, note the rounded fistfuls of sand, I took a grains, photo by Leo Kenney handful. It felt like a GSM president, Dave Wilhelm (r), presents Jeff Thole with a gritty, slushy ball—and super saturated with water. As I custom-made geological hammer in appreciation of Jeff’s held it, water seeped from between my fingers and the contributions to the GSM grains. Squeezing it more and feeling the grains, I recognized that the sand grains were very fine. I Thank you Jeff for another excellent lab! wondered, if the fine grain size was responsible for the Theresa Tweet; photos by Mark Ryan delicate patterns? Likely. Flowing Sand That brought back memories. As a kid growing up on On a warm February day, a friend and I hiked along on the shores of Lake with “sugar sand” beaches, the rail grade trail from Lilydale to Mendota where the we would build drip castles nearly every day. We dug St. Peter Sandstone bluffs hug the trail above and the holes near the shore till we hit the water line, then Mississippi River flows below. I’ve taken this pretty grabbed handfuls of sand. Then we watched our castles gsmn.org 5

May 2020 Volume 74, No. 2 grow as we let the sand and water drip through our walls which hands and fingers. This process formed similar patterns delineate the to what we saw heiaus, sacred naturally religious occurring on the structures found St. Peter all around the Sandstone bluffs. Island. Further And both south, the flows ephemeral. from Mauna Loa’s A friend hiking western flank with me introduced us to questioned why overlapping layers Surf draining from rough ‘a’ā lava the sand was upon layers of jumbles of masses of towers of ‘a’a flows. I flowing and found it difficult to assimilate the forms. The coastal More intricate sand flow patters making these town of Ho’ōpūloa was completely buried in a 1926 patterns. Hmm, flow; a new town not everyone has geology background, I explained how is still emerging as the freeze/ thaw cycles causes the sandstone to landowners decompose and to turn back into sand, especially on rebuild. We also surfaces exposed to the weather. I also noted that the saw an shape of the lobes indicated the flow direction, endangered Green something we see in rock, but less often happening in Sea Turtle on the front of our eyes. sand of the Forever being the teacher, I showed the flowing sand and Marine patterns to a couple of 7-year-olds who were walking the Conservation District. trail and encouraged them to touch and describe the Halema‘uma‘u Crater within Our next five days sand. They replied with a “ewe” and “cool.” Kilauea Caldera Kate Clover, story and photos were centered at Hawai‘i Volcanoes National Park. Established in 1916 Hawai‘i in February 2020 to see Volcanoes as the 13th national park, it is now an International Biosphere Reserve and World Heritage Site. Its 505 Last February, the Institute on Lake Superior Geology square miles contain Kīlauea with its massive caldera (ILSG) offered several GSM members the opportunity to and rift zones, and Mauna Loa, which is only 25 miles see and study the volcanoes that make up the Big Island away. Our accommodations were at Kīlauea Military of Hawai‘i, the largest island in the Hawaiian Island Camp, a military facility located along the caldera’s rim chain. Two volcanos are active: Mauna Loa is the largest and used today for military family recreation and by shield volcano, Kīlauea is the youngest. The other three, nonprofit groups. From lovely cottages to dorm bunk Kohala, Mauna Kea, and Hualālai are dormant. There is beds, we experienced it all. a sixth volcano, Lo‘ihi, rising below the sea to the southeast. Kīlauea Caldera, over 4 square miles, is the heart of the National Park. Halema‘uma‘u Crater within the caldera The field trip's leader, Canadian geologist, Allan is its most active vent. Eruptions have covered part of the MacTavish, met five GSM enthusiasts along with three circular Crater Rim Drive and destabilized the museum other professional and geologists in Kailua observatory as Kona, an historic well as seaside town on the obliterating Big Island's west parts of the coast. We soon left Chain of Kona heading south Craters Road. in three vehicles. Our Other eruptions first stop was along the East Kealakekua Bay Rift Zone have State Historical Park added 500 acres which preserves the to Hawaii’s Footprints in partially-lithified ash culture and history of south shore. the Hawaiian people. The crater can be seen from several sites: near the visitor Here we were first center at Steaming Vistas, at the Keanakāko’i overlook, Model showing the 5 volcanoes on the introduced to the and from the road. No matter from where it is viewed, it Big Island massive drystone is an awesome sight. gsmn.org 6

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The park road system has access to trails leading to the various terrains where endless Kilauea Iki crater seen from its rim combinations of lava forms can be viewed: spatter cones, spatter rims, fissures, lava tubes, tree molds, plus examples of pāhoehoe and ʻaʻā lavas. The Ka’ū Desert Trail follows a path once used by Group in Kilauea Iki crater Hawaiian villagers and warriors. A 1790 eruption trapped a war party of Hawaiians who left their surfaces smooth but others with piles of crustal plates footprints in the ash; some escaped and some did not. jumbled like “ice out” sheets. Cairns marked the path Mauna Iki Crater Trail branches off and shows across the “lake” surface which different forms of was surprisingly warm to the lavas, and I learned a touch. new word: tumulus. The Chain of Craters Road Tumuli form when a descends abruptly to the coast thin crust of pāhoehoe over the Hōlei Pali. (A pali is a lava receives a cliff face of a lava flow.) The subsequent pulse of scenic 18.8-mile-long drive with molten lava and lifts an elevation change of 3,700 feet the original into a crosses lava flow upon lava Nēnē swollen dome. They flow, both recent and ancient. A jumble of lavas appear in all sizes The youngest flows are the darkest, the oldest flows are from bumps to great hills. Here, Joanie Furlong vegetated. At the very end of this road lies the Pu‘uloa discovered our first glimpse of Pele’s hair, thin threads of Hill Historic Petroglyphs, an archeological site still volcanic glass elongated as they traveled through the air. used by traditional Hawaiian families where at least Devastation Trail begins on forested land where 23,000 figures, shapes and forms are carved into the flowers abound. But soon the trail comes to an extensive pāhoehoe. Also along the road, we found a begging nēnē, moonscape of cinders and towering lava fountains left the Hawaiian goose and state bird. From a population of from the 37-day-long Kīlauea Iki eruption in 1959. just 30 endangered birds in 1952, there are now estimated to be 800 in the The Kīlauea Iki Trail was perhaps the favorite hike. wild. Kīlauea Iki Crater is deep and now solidified, but it was once filled with a molten lava lake. (Craters are By far the most formed when an exciting day underlying lava included a 75-mile suddenly drains Paradise Helicopter away and the flight over the surface collapses.) Kīlauea Caldera The trail begins and the East Rift along the rim Zone, over much of where one can look the area which we Recent ropy pāhoehoe across to the vent had walked. As under a huge there were no side doors on the helicopter, camera access cinder cone. was unobstructed, and it was breathtaking looking down Around the floor of into the greatly enlarged Halema‘uma‘u Crater. Dr. Jack Lava does not respect traffic laws! the crater are “bath Lockwood, retired from the Hawaiian Volcano tub rings” Observatory had purchased “land” over one of the indicating the levels of different flows. Descending to the massive flows so that he could always land a helicopter. floor of the crater, the top of the “lake,” we found some And we did! Walking on six-year-old lava, identifying gsmn.org 7

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the Onomea Taking phots from an Valley, near open helicopter and the Hilo, in 1977 helicopter on a recent was lava flow spectacularly filled with tropical trees, colorful flowers, Olivine sand waterfalls, and grains from flow features, and breathtaking Papakōlea listening to the tinkle vistas. Further Beach, photo of the brittle north the land is by Leo pāhoehoe will surely covered with Kenney remain in our ash, deeply memories. Together incised by rivers. Originally we walked up the home to native taro growers, nearby cinder cone associated with fissure 9, one of the the sugar plantations that most prolific of the 2018 eruptions. The residual heat replaced them are mostly could be felt through gone. At Laupāhoehoe Point, our boots. Later we a tsunami originating in an Green sand beach would visit the Aleutian Islands in 1946 event killed many people. undamaged home of Tsunami evacuation route signs abound. Mark Bishop, GSM The northern peninsula was formed by the oldest member and owner of volcano, Kohala. Here the beach Niagara Cave in has eroded out of a saprolitized Harmony, MN. (weathered) alkaline mafic flow. What could be more The process continues to round appropriate after that the flow into boulders. Maui Snow and observatories on Mauna Kea than seeing Mauna looms across the strait. Down a Kea’s snow? Hawaiians were shoveling pickup beds dirt road is Mo’okini Heiau, one full. Kids were sledding. Surfers had other uses for their of the most sacred heiau. Rounded and polished boards. From the summit, the telescopes at Mauna Kea Dedicated to the War God, it was black sand from Punalu’u Beach, photo by Leo Observatory looked like 13 mushrooms in the snow. a place of ritual sacrifice. The Kenney Next, we visited two entirely different beaches, the first, kapu, the set of laws governing all Punalu’u Beach was composed of black sand (shattered Hawaiian religious life, allowed only the most powerful obsidian) and the other, Papakōlea, of green sand to enter, but it was opened to all in 1978. The massive (olivine crystals). The but desolate site is still cared for by the same family. black sand beach was Lapakahi State Historical Park on the northwest shore inviting with Green of the island preserves the foundations of a once Turtles landing in the flourishing fishing village. Houses, canoe sheds, salt waves. But reaching production, places of worship, and garden plots Papakōlea 's green surround the bay. But fresh water was scarce on this sands was a test. We western slope. Rising sea level flooded the wells, all walked in on a causing the road that crossed a village to poorly-consolidated, be Turtles on a black sand beach deeply-incised abandoned. grassland. The U-shaped beach, surrounded by dark The white cliffs of ash imbedded with olivine crystals was sand beautiful, but unfortunately the wind embedded the Hāpuna sand and ash into our sandwiches, hair, teeth, clothes, Beach is and shoes. To return to the parking lot, a few of us bordered hitched a ride from a local business that provided a ride by an worthy of a bucking bronco. That in itself was an unusual adventure. outcrop Unlike the dry Kona side of the island, the eastside is filed with lush. The Hawaii Tropical Botanical Gardens, created in visible Deeply incised valleys at Pololū Valley Lookout gsmn.org 8

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olivine and pyroxene phenocrysts. Further south, the taxi. I younger Mauna Loa flows overrides the older Hualālail compromised and lava flows. The grass lands of Pu’uwa’awa’a Dry Forest chose the water Site had new plants to see. taxi going in one Our final destination, the King Kamehamehai Kona direction to see the Beach Hotel was as lovely as it sounds, appreciated for coastal cliffs from its luxury, its many dioramas of Hawaiian history and the sea and then displays of artifacts. After that all that remained was hiked back to Coastal view of cliffs near Cathedral cove relaxing, whale watching, and packing to return home. town. This was an The end is as hard to write as it was to do. Allan excellent decision. MacTavish, our guide, created a thorough survey of a The short boat ride large territory; his field guide was excellent and useable, provided a great his enthusiasm unbounded. My thanks to him and to view of the steep, Peter Hinz, Canadian geologist and trip co-leader. The white coastal cliffs. professional geologists were all supportive. It was a And when I asked a great group of travelers. Should he offer the trip again, I boat crew member can recommend it heartily. what the rock was, Mary Kay Arthur; photos by Dave Wilhelm she said without pausing, New Zealand Travels to Mercury Bay “ignimbrite.” After reaching the beach, I Ignimbrite at I count myself as among the fortunate who were able to set off to see the Cathedral Cove with chunks of travel as planned before the COVID-19 lockdown early rock up close. I had in 2020. My travels took me to New Zealand, which has pumice and glassy done research and obsidian long been on my bucket list. My two weeks there were learned that this not long enough - I would return tomorrow. rock, ignimbrite or welded tuff, was produced by Among the areas I visited was Mercury Bay on the explosive volcanic eruptions that had occurred about rugged Coromandel Peninsula on the east coast of New eight million years Zealand’s North Island, about a 2.5-hour drive from ago. The close-up Auckland. The peninsula juts north and separates the view of these Hauraki Gulf pyroclastic and Firth of sediments revealed Thames in the tiny angular blocks west from the of pumice and Pacific to the east. It is at the end of a belt of volcanic rocks. Intense wave action along Mercury or the Coromandel coast results Red Bay is a in erosion and the formation large V-shaped of caves, blowholes, arches bay that was and sea stacks. See the people named in 1769 for scale View of the Coromandel coast from the upland by English trail Navigator glassy shards in a fine-grained matrix of volcanic ash, Capt. James Cook when he landed to make an quartz and feldspar. Looking at the cliffs, I tried to astronomical observation of a Transit of Mercury. The imagine the magnitude of the eruptions necessary to area is renowned for both its shorelines and forests. The create these massive pyroclastic deposits. Cathedral Cove area is also known as Whanganui A Hei The striking color of the sand from Mercury Bay comes Marine Reserve. from the polished shell plates of the pink barnacle As I had seen photo micrographs of the beautiful pink Notomegabalanus decorus, a species found only in waters sand from Cathedral Cove on Mercury Bay, and being a around New Zealand. This barnacle is large and reaches sand collector, I was hoping to actually find this sand up to 3 inches at the base. It is the most characteristic for myself and observe the regional geology and marine and well-known barnacle of the New Zealand shelf. environment. We drove to the town of Hahei, and from However, unlike other barnacles, this one is seldom there, Cathedral Cove is either a 90-minute hike through seen as it only occurs sub-tidally at around 25 meters the verdant fern forest or a 15-minute ride on the water depth. Except we find their remains in sand. gsmn.org 9

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Barnacles have shells with New and Unusual Fossils in Minnesota's diverse body plates, and Ordovician Strata the best examples in this sample are the triangular I've been collecting fossils in Platteville and Decorah plate with grooves or exposures for 45+ years. In that time, I've found or have hollow channels near 2 seen most all of the usual marine fauna the Ordovician- o’clock position and the aged (~440-485 Ma) strata has to offer, including more elongated pink trilobites, brachiopods, cephalopods, Receptaculites, fragment with the ridge rugose and tabulate corals, Raufella, crinoids, and even a Sand from Mercury Bay, photo by near 4 o’clock. rare conulariid. Most are abundant and can be found in Leo Kenney Identifying barnacle plates several locations across southern Minnesota. is not easy. Their conical or volcano-shaped shell is In late 2009, while scouring new fossiliferous exposures comprised of six rigid carbonate plates; and its in Cannon Falls, MN, I found, besides the usual fare – operculum (the top plates) is composed of another two including a splendid 6-inch cephalopod tail - three pairs of plates which open and close as the animal feeds specimens of a very unusual fossil I'd never seen before. on plankton and drifting plant material. If you notice that The small fingernail-sized fossils were all on the surface, the shapes of the pink fragments do not all look alike, and fairly close to each other. I think the layer in which that is because the barnacle base shell has four distinct the fossils were found may be the Cummingsville plates, and the operculum has another two pairs of Formation which overlies and interbeds with the top of distinct plates. The triangular plate with hollow channels the Decorah shale. near 2 o’clock, is a “typical” body plate. The elongated fragment near 4 o’clock, is an opercular plate. To add a further challenge and confusion to identification, the inner and outer faces of these plates are different, and the right and left plates mirror one another (think right and left hands). Other biogenic grains in this sand include tiny gastropods, as well as remains of sea urchin spines (the striated green rods), coralline algae (the smooth white rods), and bivalves. This sand includes more than barnacle fragments and the remnants of local marine life. Look closely at the sand’s The first three specimens matrix, the tiny grains in the background. The clear quartz and yellowish feldspar grains are the pyroclastic Each specimen is comprised of a rounded cap about 10 to sediments deposited about 8 million years ago that have 12 millimeters in diameter and about half as thick. What eroded from the cliff makes them stand out is the fact each has a stalk (or the face and are now part remnant of one) attached at the bottom. The cap of the of the beach sand. largest displayed the most detail, with an interlaced Yes, I’m grateful I texture visible across the surface and a radial aperture made the trip to perhaps used to take in and expel nutrient-rich waters. Cathedral Cove. The central stem pokes out from the middle of the lower Seeing the coastal side of the cap, but sometimes a cap displays signs of the cliffs from the water, remains of examining the similar-sized ignimbrite, savoring connection points the beauty of the site, branching off the Kate hiking hiking through the side surface. At in New Zea- verdant fern forest first sight, they land’s fern and finding the pink remind one of forest where tiny mushrooms, tree ferns barnacle sand made for a memorable day. but the grow 20-30 resemblance is in ft. tall So good indeed, we returned for a second form only. visit a couple of days Since my initial later. discovery, I've Kate Clover often returned to the site, Specimen close-up showing radial aperture gsmn.org 10

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searching across the exposure for more of these strange Curved Sioux Quartzite little fossils. But it took seven years to find another, and three years after that to find two more. All were found This curved bit of Sioux Quartzite (SQ) is from a quarry within a square yard of the first three specimens, so I located a half mile west of the Jeffers Petroglyphs in have narrowed my search to that single spot. I have Cottonwood County, Minnesota. For years I have revisited after rains and winters and frosts and it took me puzzled about its curved form. Naturally-broken pieces of another three years, in late 2019 to find two more. SQ are slabbed, flat, layered, and range in color from Fortunately, the current health pandemic has not kept me light yellowish-pink to deep burgundy. Some are from sparkly, some are dull in appearance, and some show pursuing my ripple marks from being under water. But all are flat and favorite have broken along straight lines. The quarried stone solitary chips (this being one of them) are broken by rock activity, and I crushers, but they still break along straight edges. Until returned this this piece. year in early The striated rock April and pictured here found two (10x6x2 inches; 9 more, and pounds) was again two picked up two weeks later miles south of the Mystery four (!) more Petroglyphs. fossil in along with Over the years, situ and some pieces of numerous rocks four recent possible of SQ have been specimens truncated placed in my stalks. garden, and this Not knowing if they piece lives were coral, sponges or beneath the bay Curved fragment of Sioux Quartzite, photo by something else entirely, window. It shows Carol Kissner I've emailed photos to banding and some invertebrate paleontologists; and so far, I've cross-bedding. Most SQ rocks are solid colored without learned they were definitely not corals. So maybe marks or lines. sponges? One expert suggested I have a specimen cut I grew up near the and polished and examined under a powerful Petroglyphs and the microscope to look for spicules – a definitive skeletal Red Rock Dells. The element of sponges. Jeff Thole (Macalester's Geology Lab Dells, a local name manager) and I have discussed doing just that, but now for a quartzite things are in limbo with the Coronavirus lockdown. As formation, is yet, I've found nothing in the literature or online except a located two miles photograph of what west and two miles looks to be a similar north of the fossil found in Petroglyphs, and Striated block of Sioux Quartzite, photo by Ontario, although it features a stepped Kate Clover was stated the 30-foot waterfall. specimen itself was The surrounding area is featureless, barely rolling missing. Last autumn, farmland with nothing to indicate that a treasure is at the National nearby. The Dells are located on a gravel road with a Museum of Natural small bridge over an ordinary creek. But get out of the History in Paris, I saw car at the top Mystery sponge descendants? several similar (albeit of the (very) much larger) fossil small hill sponges from the Cretaceous that were a good 20 where a centimeters (about eight inches) in size. picnic Could my tiny fossils be their ancient ancestors? Who building is knows? But the mystery continues to hold my interest standing, and and will keep me searching for answers. a few yards Cross bedding on a block of Sioux Quartzite, photo Mark Ryan to the south a by Carol Kissner gsmn.org 11

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gorge opens up with the waterfall that comes off a one hundred-foot staircase of stepped Sioux Quartzite from which, when flow is available, water cascades down. Fifty feet beyond the southern boundary of the parkland, the flat farmland begins again. This amazing little place appears out of nowhere and recedes as it begins At the base of the waterfall, the gorge forms two “rooms” with 30-foot walls of Sioux Quartzite. While Native Americans marked the petroglyph site (four miles away) with figures, none have been found at the waterfall site. “Visible in the rock are distinct layers, indications of advancing and retreating of shore environments. In many places cross bedding is evident, the result of water transport and deposition of the sand grains. The rock is about 1.6 billion years old, is composed of well sorted and well-rounded grains of quartz. The quartz sand is a remnant of granite erosion, being more resistant to weathering than the feldspar and micas. The rounded nature of the grains indicates that it traveled a long distance to get here (being more rounded as it bounced and bumped into other rocks). The composition and size of the bedrock indicates that a very large mountain range must have been present to supply all of the sand. The ripple marks visible here and many other places, and the large Figures 26 and 27, illustrate cross bedding. From video amount of sediments indicate a braided stream environment lecture: GeoElements of Michigan’s Keweenaw: The typical of rivers emptying into an ocean or large lake similar to Jacobsville Sandstone the Mississippi emptying into the Gulf of Mexico. Analysis of the ripple marks reveal a current direction of just east of due south. The red to purple color comes from the presence of iron Michigan Technological University. When viewing the oxides (rust) coating individual sand grains.” – photo and text video, I noticed a similarity of formation with Sioux from MN DNR Minerals Education Workshop 2005; Field Quartzite. Both involve erosion of large mountains; sand Trip guide by Dr. Dean Moosavi and Rick Ruhanen transported into braided rivers resulting in channeling and cross-bedding. Fig. 26 and 27 has been recreated One mile east The waterfall from the video. of the Dells, dries up season- An interesting side note of living with Sioux Quartzite – ally, but the pool the creek is at the base of the dammed to the well on our farm was drilled to 116 feet but SQ Red Rock Dells create a small bedrock was struck at 114 feet. We hit water and also got always has wa- lake and a weather forecaster of sorts. Two days before a storm ter. Photo credit: another small the well water would turn opaque orange. A geologist MN DNR Min- waterfall can friend said that an “unusually low barometric pressure erals Education be found. It could lift water toward the surface, bringing with it Workshop 2005; dissolved Field Trip guide does not have the gorges minerals/orange by Dr. Dean color.” The taste Moosavi and however. did not change, Rick Ruhanen So why is but one could not this piece do laundry until curved? I have no formal schooling in geology, but the weather have consumed geology lectures, library CDs, YouTube system passed. videos, books, and have faithfully attended the geology Well #185558 is lectures at GSM. Finally, I found an acceptable now capped off. explanation to the curved quartzite. The farm located During the COVID-time, Dave Wilhelm sent an email to next to the Red Rock Dells was once owned by Carol’s GSM members with a link https://pages.mtu.edu/ grandfather. The location was pictured on a postcard. ~raman/Jacobsville.mp4, provided by Kate Clover, to a Carol Kissner lecture about Jacobsville Sandstone in Michigan authored by Dr. Bill Rose, retired geology professor from

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Good Geological Sites in Ohio Serpent Mound is also on and Other Fun Stuff the western flank of an astrobleme (an impact My mother and siblings live in Columbus, Ohio, and I structure), the end of a visit there a lot. The brother-in-law and I have made a series of meteorites which practice of doing day trips over the years to see all sorts hit the earth (think of interesting things, including visiting interesting Shoemaker-Levy 9) at the geological sites. end of the Paleozoic. The In fall and winter 2019-2020, after first thinking about a first hit was in possible GSM tour to the area, I decided to write an Scandinavia, and they article on some interesting sites in Ohio that I have ranged down across to Ohio. This was just as visited. With help from my writing, GSM Members can Serpent Mound Crater, red oval maybe do their own trips. Two books are recommended Pangaea was finally shows approximate perimeter over and over: Ohio Rocks by Albert B. Dickas, and coming together. The (1974 photo), Wikimedia Commons Roadside Geology of Ohio (Mountain Press). They are good, and a real geologist will help if you can find one. towns of Sinking Ohio is geologically diverse. From Southwest to Spring and Locust Northeast, the bedrock is Ordovician, Silurian, Devonian, Grove are outside Mississippian, Pennsylvanian (Carboniferous), and the 4-mile diameter Permian in age. Some of these strata are missing in disturbance. SR 73 Minnesota, so an Ohio visit presents different stuff to see. crosses the There are also a number of interesting archaeological disturbance on the sites, one concurrent with a geological site. southwest edge, and Buckeye Furnace, south Ohio. This is a self-guided site, SR 41 from N to S at an old iron refinery. Before, during and after the Civil the eastern side. War, Ohio, West Virginia and Kentucky were big iron Parker Ridge Road mining areas. Buckeye Furnace is one place where the traverses the center iron was smelted and poured into ‘pigs’ which were then E to W. After your shipped up the canals to the steel mills in Cleveland and visit, drive Pittsburgh. The ore came from three layers: the Little Red southeast into Block, Guinea Fowl and Yellow Kidney Ores. It was Locust Grove on SR scraped from foot-thick layers on the hillsides and 73 and stop at averaged 30-40% ore. Streams flowing off the House of Phaecops, Appalachian Mountains deposited the iron ore in the an eclectic rock shop wetlands of the Hanging Rock region of Ohio, Kentucky Aerial view of Serpent Mound. This is where you can buy and West Virginia during Pennsylvanian times. The ore an old picture; the tree in the bend is Serpent Mound T- was deposited above the Vanport Limestone, which was gone and the bridge over the spiral is shirts and chat with also mined for flux to process the ore. Iron mining in the also gone. Photo: Wikimedia Commons the proprietor about Ohio area ended before WWI, after the better quality and the mound and much more abundant ore was discovered on the Iron trilobites and other fun stuff. Plan for 2-3 hours. The site Range in Minnesota. In the park, you can see the is off SR 73 two miles east of Loudon. buildings where the smelting took place; the museum Flint Ridge State Memorial, central Ohio. This is a and gift shop are open on weekends. The covered bridge geological and archaeological site. The beds of flint are is refurbished, but is still interesting. Plan for 1-2 hours part of the uppermost unit of the Vanport Limestone, a without the museum. Buckeye Furnace is located 9 miles Pennsylvanian age deposit. In pre-Columbian times (and from Wellston, on State Road (SR) 165-167. after), Native tribes Serpent Mound, south central Ohio. Serpent Mound is considered Flint Ridge a a world heritage site, with a constructed serpent which is neutral site. Anyone could also an observatory for the seasons. The serpent marks come and mine flint for solar and lunar positions: sunset at summer solstice, weapons and tools. The winter solstice sunrise, sunrise and sunset at the flint here is particularly equinoxes and lunar risings and settings. These fine, 96-99% pure silica, and astronomical alignments were discovered only recently it works very well. since 2000. Climb the tower and view the serpent from Specimens of this flint have been found all over North above, and then walk around it. The museum and gift Pennsylvanian age flint, photo by shop are good, and the film explaining the culture is well America as it was widely Kate Clover worth watching. traded. This flint is gsmn.org 13

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especially colorful—red, yellow and brown in addition to the usual grey and white, and occasionally has bits of druzy stuff as well. Collecting is prohibited in the park, but every winter more flint is heaved up from the soil. If you look at the side of the roads that run around the park, you will find lots of flint in the ditches. There is a small museum and gift shop. Plan for 1-2 hours. This site is located off -I 70, north of Brownsville between Columbus and Zanesville. Hueston Woods State Park, southwest Ohio. This is the site of a farm that was preserved as a park. They dammed a river and created Acton lake, something which Ohio generally lacks. In state parks you usually cannot collect, but there a few sites here where you can Pathway through the Palace of the Gods in Ohio Caverns. Photo: collect for personal use. There is a covered bridge in the Wikimedia Commons park, and the riverbed below is full of late Ordovician fossils where you may collect. Park in the picnic spot and outside the caverns. Take your own flashlight to see take a hammer. I spent about 45 minutes and found a lot, minerals in better detail. Plan for at least 3 hours which so a dedicated person will be able to find many includes a tour. There are also fun shops in West Liberty, interesting specimens if they walk up river. Many so check them out as well. This is located 4 miles east of brachiopods, horn corals and the like. Supposedly there West Liberty on SR 245. are also trilobites. There is a small museum in the park, Hungry when traveling? The brother-in-law and I always tried to eat at the local mom and pop places in the small towns, and we were always happy. Why eat at chains, when every small town has a local diner, and they are pretty good for the basics. Especially the pies. Deborah Naffziger

Ordovician horn coral, photo by Kate Clover ChronoStratigraphic Chart which details what might be found, but it is sketchy so The International Commission on Stratigraphy (ICS) has you can skip it and just collect for yourself. Apparently a long tradition of producing international charts that there is a map for collecting available at the Park Office, communicate higher-order divisions of geological time but when we visited, nobody was there. Plan for and actual knowledge on the absolute numerical ages of however long you are willing to collect fossils, an hour at their boundaries. The primary objective of ICS is to least. This site is off SR 177, five miles north of Oxford, define precisely a global standard set of time correlative just east of the Indiana state line. units (Systems, Series, and Stages) for stratigraphic successions worldwide. These units are, in turn, the basis Ohio Caverns, east central Ohio. This is one of Ohio’s for the Periods, Epochs and Ages of the Geological Time many caves, but they claim to be the most colorful. I Scale. Setting an international global standard is found it to be so. The Devonian Columbus Limestone is fundamental for expressing geological knowledge. It is the bedrock in the cave, which has been subsequently also of considerable pragmatic importance as it provides carved by groundwater over the millennia. The largest the framework through which regional-scale higher- crystal deposits are estimated to be 250,000 years old. resolution divisions can be linked, equated and collated. Many of the cave formations are calcite, but there are also This is a status update on the International colorful iron oxide and manganese dioxide formations. Chronostratigraphic Chart and the ICS website There is a gift shop and small museum, and plenty of www.stratigraphy.org. (Cohen et al., 2013, Episodes, v. picnic areas, bathrooms and general places to roam 36, no. 3) gsmn.org 14

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gsmn.org 15 Press Minnesota’s Geologist The Life of Newton Horace Winchell 2020 Author: Sue Leaf The story of the scientist who first mapped Minnesota’s geology, set against the backdrop of early scientific inquiry in the state Tracing Newton Horace Winchell’s path to becoming a leading light of an emerging scientific field, Minnesota’s Geologist recreates the early days of scientific inquiry in Minnesota, when one man’s passion for learning could unlock secrets of the state’s distant past and present landscape. This first telling of Winchell’s life story is set against a backdrop of Minnesota’s geological complexity and splendor. Sue Leaf has done a great service for the people of Minnesota and beyond by telling the story of Newton Horace Winchell so thoughtfully and beautifully. Readers of Minnesota's Geologist will be rewarded with new insights into why the world around us functions as it does. This is a book that I've been hoping for. — Harvey Thorleifson, director, Minnesota Geological Survey

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