In the course of doing their normal work—drilling cores, studying outcrops, and looking for patterns in rock layers—two IGWS geologists believe they’ve found a fault and a fault extension in southern Indiana that haven’t been mapped before.

Don Tripp and Sarah Burgess were drilling south of the Mt. Carmel Fault east of Paoli off State Road 56 in November when they hit a line of sinkholes. They moved the drilling downhill and hit something they didn’t expect to see: St. Genevieve Limestone instead of rocks of the West Baden Group, as well as fractures and voids in the core. This, Burgess explained, was evidence of an anticlinal structure—an arch-shaped trap below the surface that could contain, gas, oil, or water. Those structures are formed by pressure squeezing rock layers into folds.

More data came from studying rock types and elevations at Mitchell Plateau outcrops in Washington County. Before going out to a site, Tripp runs through some trigonometry calculations so he can anticipate what type of rock will appear at specific points. His predictions are usually accurate to within about 5 feet, but if they're off by 30 or 40 feet, there could be “something going on,” like a fault. In mid-January while back in the field, Tripp and Burgess noticed a drastic difference among their data points in the elevations where stratigraphic layers met. That displacement is called offset. Among these points—south of Salem, near the Blue River—they were seeing 70 to 100 feet of offset.

“So, clearly, it’s been shifted,” Burgess said.

Based on their data, they believe that the Mt. Carmel Fault extends 6 to 20 miles further south of where it was previously mapped in Washington County, and that a different but probably related north-south fault exists about 10 miles to the east, southeast of Salem.

When the weather warms up, they’d like to take a boat out on the Blue River to find outcrops and gather clues like fault gouges from the more visible rock layers. They also could conduct seismic reflection or refraction using their drill holes to produce images of what’s going on in the deep subsurface.

Burgess has done some exploring of the area underground, at Cave River Valley on the Mitchell Plateau north of Campbellsburg. From that vantage point, one can see evidence of faulting in slickensides—sections of rock that have been rubbed smooth because of shifting.

Burgess believes that the chemical makeup of rocks in this area may be one reason why these faults haven’t been mapped before. The Mitchell Plateau is made up of carbonates, so they dissolve in acidic groundwater and can erode to the point where they can look flat even though they’re different kinds of rock, she said. “So, there’s not a good surface expression of the fault, even though it’s a very big (fault) system and it’s unlikely to just stop (at the point where it was previously mapped to stop),” she said.

Though faults are most broadly associated with earthquake danger, Burgess said these faults are not in a very active zone, so there’s “not a lot of concern” for damaging earthquakes in this region. What faults can point to are trapped resources such as springs, oil, and natural gas. IGWS staff already had mapped several perennial springs in this region for a separate project—another clue that faults may be present—and Burgess noted that several exploratory oil wells had been placed in this region.

“It’s less of an earthquake hazard and more of part of a predictive feature of some natural resources,” she said about the new fault data.

If he hadn’t become a geologist, Dr. Henry Gray would have been an archaeologist. He enjoys unearthing layers of history, always has, since he was a kid poring over encyclopedias and building a museum in his grandma’s attic. And if his body would work with him, he’d still be out there, digging in the dirt and climbing outcrops, making careful notes to take back to his office to plot, to describe, to study.

On March 23, at a party celebrating his 100th birthday, Gray was presented a Distinguished Geologist award from Professional Geologists of Indiana, a birthday proclamation from the Indiana Senate, a Distinguished Hoosier Award from the governor’s office, and honorary IU alumni status. He is already a Sagamore of the Wabash—one of the state’s highest honors—awarded upon his so-called retirement in 1987.

A celebrated stratigrapher and part-time geology professor, Gray has taught generations of earth scientists and continues to do so. Since retiring from the IGWS 35 years ago, he’s now been volunteering his time, research, and mentorship for longer than he was paid to do it.

Why?

“There’s still lots of work to do,” he says. “I wish I could do more.”

READ MORE about Henry’s life and career on our new IGWS website section for news.

See additional photos from the party—which IGWS Director Todd Thompson likened to a "Survey family reunion"—on ResourceSpace at this link.

Yes, we’ve added pages to our website. “Outreach” has been renamed to “News & Outreach,” and the E-Geo News has been moved to this tab from “Services” where it used to be. You’ll also find a couple “staff spotlights” there including the full Henry Gray story; a section on research projects; and a section on information services projects. We’ll still be sending out the E-Geo News each month, but we’ll also be posting news items to these subcategories monthly, mostly copying items over from the newsletter. This enables individual stories to be shared easier through social media and email to audiences that might not scroll through every item in the E-Geo News. For instance, IU Bloomington Today sent a link to Gray's birthday story to its all-campus audience earlier this week.

Browse the News & Outreach section at https://igws.indiana.edu/outreachevents.

During the first weekend in June, the IGWS will host its first open-invitation public events in more than two years.

From 1 to 5 p.m. Friday, June 3, an open house will take place at our renovated building at 1001 E. 10th St. in Bloomington. This event was supposed to happen in October 2021 but had to be postponed because of COVID. Visitors can enjoy lightning talks from IGWS scientists about their research, lab tours, and other activities.

The grand opening of the IGWS Learning Lab will happen the same day from 4 to 7 p.m. Teachers and other interested visitors can explore the IGWS’s Education Collection in new ways than ever before in a bright, fully renovated space designed for hands-on learning and exploration of fossils, minerals, geodes, coals, rock cores, and many other items not often visible to the public. “The whole point is to be able to touch specimens that were previously held behind locked doors,” said IGWS Education and Outreach Coordinator Polly Sturgeon, who’s been working on the Education Collection and Learning Lab concepts since 2017 with Collections Manager Jenna Lanman and several IU Bloomington students. These items had been stored in various closets, offices, and the basement; now, they have been cataloged and organized into cabinets and pull-out drawers. The Learning Lab will be accessible to visitors from 9 a.m. to 5 p.m. Mondays-Fridays, with weekend and evening hours available for special events.

On Saturday, June 4 from 10 a.m. to 3 p.m., the IGWS will host its first Limestone Month Festival outside the main IGWS entrance and in the new, grassy Northwest Quad behind the building (formerly a parking lot). This free, no-ticket, all-ages event will include activities like limestone carving, a photo booth, fossil and rock inspecting, and lessons and games provided by area museums. Food trucks and vendors will also be present. Vendors involved in the cultural, recreational, or geological aspects of limestone are welcome to contact Sturgeon at 812-855-1378 or proot@indiana.edu for more information about participating.

• Victoria Leffel joined the IGWS staff as a research geologist on March 28. She comes from Lafayette, where she had worked as an engineering specialist and as a geotechnical engineering geologist for the Indiana Department of Transportation. She holds a bachelor's degree in geology and a master's degree in environmental public health, both from Purdue University, and has experience in geohazard corrections related to mine subsidence, karst, and slope stability issues, as well as stormwater design and wetland and endangered species protections.

• Research geologist Don Tripp will mark his five-year anniversary with the IGWS this month. Tripp started as a teams coordinator for the Indiana lead sampling project, then was pulled into various geophysical and springs/karst projects before moving into his current job.

• The IGWS will begin advertising to hire a web developer and a digital imaging specialist within the next few weeks. Check igws.indiana.edu for postings and application deadlines.

• A new exhibit has been installed in the IGWS lobby. Called “eARTh: The art of earth science,” it highlights the IGWS’s long history of showing and telling through scientific illustrations. Before he became Indiana’s first geologist in 1837, David Dale Owen studied painting, drawing, and lithography and worked in a New York City printing office. He exercised those skills to create detailed illustrations of Midwest landscapes and geological structures. More than 100 years later, artist-draftsmen Robert “Bob” Judah (employed 1955-1977) and Wilbur “Bill” Stalions (employed 1977-2000) used some of the same techniques to illustrate geologic reports which were read by industry professionals and the general public. Today, several IGWS staff members use drawing software to illustrate posters, manuscripts, and presentations. The lobby exhibit, hanging through August, includes several original illustrations found in IGWS archives, as well as part of the diorama which was a fixture in the Geological Sciences building for many years. Stalions built that, too.

• IGWS research scientists Babak Shabani and Ryan Kammer were coauthors on a paper accepted for publication in the journal Energies titled "Effects of Hydrogeological Heterogeneity on CO2 Migration and Mineral Trapping: 3D Reactive Transport Modeling of Geological CO2 Storage in the Mt. Simon Sandstone, Indiana, USA". It can be read in Energies’ special issue CO2 Enhanced Oil Recovery and Carbon Sequestration.

• Polly Sturgeon represented the IGWS at the grand reopening of the Dinosphere at the Indianapolis Children’s Museum on March 19. She used specimens from the Education Collection to explore fossils that are commonly mistaken for dinosaur fossils and discussed why dinosaur fossils are not present in Indiana’s bedrock.

• IGWS Director Todd Thompson presented at the Indiana Academy of Science Annual Meeting in Indianapolis on March 26. He spoke about the process involved in “Twenty-first Century Geological Mapping of the State.” Sturgeon also was there to promote IGWS resources to conference participants.

The Indiana Geological and Water Survey, a longstanding institute of Indiana University, conducts research; surveys the state; collects and preserves geologic specimens and data; and disseminates information to contribute to the mitigation of geologic hazards and the wise stewardship of the energy, mineral, and water resources of Indiana.

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