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New map outlines seismic faults across DFW region

Study by SMU, UT Austin and Stanford scientists rates faults for potential earthquakes; Faults under DFW urban area viewed as lower quake hazard

 

DALLAS (SMU) – Scientists from SMU, The University of Texas at Austin and Stanford University found that the majority of faults underlying the Fort Worth Basin are as sensitive to forces that could cause them to slip as those that have hosted earthquakes in the past.

 

The new study, published July 23rd by the journal Bulletin of the Seismological Society of America (BSSA), provides the most comprehensive fault information for the region to date. 

 

Fault slip potential modeling explores two scenarios: a model based on subsurface stress on the faults prior to high-volume wastewater injection and a model of those forces reflecting increase in fluid pressure due to injection.

 

A simplified version of the fault map created by the team of researchers. The map includes faults that are visible at the surface (green) and faults that are underground (black). The solid line indicates underground faults that researchers were able to map at a high resolution. The dotted line indicates faults that were mapped at a medium resolution. According to the research, in the presence of wastewater injection activity, the majority of the faults in the area are as susceptible to slipping as those faults that have already produced earthquakes. The map also marks earthquake locations and waste-water injection well locations and amounts. Credit: UT’s Bureau of Economic Geology

None of the faults shown to have the highest potential for an earthquake are located in the most populous Dallas-Fort Worth urban area or in the areas where there are currently many wastewater disposal wells.

 

Yet, the study also found that the majority of faults underlying the Fort Worth Basin are as sensitive to forces that could cause them to slip and cause an earthquake as those that have hosted earthquakes in recent years.

 

Though the majority of the faults identified on this map have not produced an earthquake, understanding why some faults have slipped and others with similar fault slip potential have not continues to be researched, said SMU seismologist and study co-author Heather DeShon, who has been the lead investigator of a series of other studies exploring the cause of the North Texas earthquakes.

Earthquakes were virtually unheard of in North Texas until slightly more than a decade ago. But more than 200 earthquakes have occurred in the region since late 2008, ranging in magnitude from 1.6 to 4.0. A series of studies have linked these events to the disposal of wastewater from oil and gas operations by injecting it deep into the earth at high volumes, triggering “dead” faults nearby.

A total of 251 faults have been identified in the Fort Worth Basin, but the researchers suspect that more exist that haven’t been identified. 

The study found that the faults remained relatively stable if they were left undisturbed. However, wastewater injection sharply increased the chances of these faults slipping, if they weren’t managed properly.

 

“That means the whole system of faults is sensitive,” said the lead author of the study Peter L. Hennings, a research scientist from UT Austin’s Bureau of Economic Geology and the principal investigator at the Center for Integrated Seismicity Research (CISR). 

DeShon said the new study provides fundamental information regarding earthquake hazard to the Dallas-Fort Worth region.

 

“The SMU earthquake catalog and the Texas Seismic Network catalog provide necessary earthquake data for understanding faults active in Texas right now,” she said. “This study provides key information to allow the public, cities, state and federal governments and industry to understand potential hazard and design effective public policies, regulations and mitigation strategies.”

“Industrial activities can increase the probability of triggering earthquakes before they would happen naturally, but there are steps we can take to reduce that probability,” added co-author Jens-Erik Lund Snee, a doctoral student at Stanford University.

 

Earthquake rates, like wastewater injection volumes, have decreased significantly since a peak in 2012.  But as long as earthquakes occur, earthquake hazard remains. Dallas-Fort Worth remains the highest risk region for earthquakes in Texas because of population density.

Even after the earthquakes died away, North Texas residents have wondered about the region’s vulnerability to future earthquakes – especially since no map was available to pinpoint the existence of all known faults in the region.  The new data, while still incomplete, benefited from information gleaned from newly released reflection seismic data held by oil and gas companies, reanalysis of publicly available well logs, and geologic outcrop information.

U of T at Austin and Stanford University provided the fault data and calculated fault slip potential. SMU, meanwhile, has been tracking seismic activity — which measures when the earth shakes —since people in the Dallas-Fort Worth area felt the first tremors near DFW International Airport in 2008. A catalog of all those tremors was recently published in June in the journal BSSA.

SMU seismologists have also been the lead or co-authors of a series of studies on the North Texas earthquakes. SMU research showed that many of the Dallas-Fort Worth earthquakes were triggered by increases in pore pressure — the pressure of groundwater trapped within tiny spaces inside rocks in the subsurface. An independent study done by SMU’s seismologist Beatrice Magnani found that wastewater injection reactivated dormant faults near Dallas that had been dormant for the last 300 million years.  

DeShon said any future plan to mine for oil or natural gas in Fort Worth basin should be done with an understanding that the basin contains several faults that are highly-sensitive to pore-pressure changes. The study noted that rates of injection dropped sharply in the Fort Worth basin, but the practice still continues. Most of the injection that has taken place has been concentrated in the Johnson, Tarrant, and Parker counties, near areas of continued seismic activity.  

“The largest earthquake the Dallas-Fort Worth region experienced was a magnitude 4 in 2015” DeShon said. “The U.S. Geological Survey and Red Cross provide practical preparedness advice for your home and work places. Just as we prepare for tornado season in north Texas, it remains important for us to have a plan for experiencing earthquake shaking.”

Many outlets covered the news:

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SMU’s catalog of North Texas earthquakes confirms continuing effects of wastewater disposal

A comprehensive catalog of earthquake sequences in Texas’s Fort Worth Basin, from 2008 to 2018, provides a closer look at how wastewater disposal from oil and gas exploration has changed the seismic landscape in the basin.

In their report published in the Bulletin of the Seismological Society of America, Louis Quinones and Heather DeShon of Southern Methodist University (SMU) and colleagues confirmed that seismicity rates in the basin have decreased since 2014, a trend that appears to correspond with a decrease in wastewater injection.

However, their analysis also noted that new faults have become active during this period, and that seismicity continues at a greater distance from injection wells over time, suggesting that “far-field” changes in seismic stress will be important for understanding the basin’s future earthquake hazard potential.

“One thing we have come to appreciate is how broadly injection in the basin has modified stress within entire basin,” said DeShon.

The first thing researchers noted with wastewater injection into the basin “was the reactivation of individual faults,” she added, “and what we’re now starting to see is essentially the leftover energy on all sorts of little faults being released by the cumulative volume that’s been put into the basin.”

The earthquake catalog published in BSSA reported all seismicity recorded by networks operated by SMU between 2008 and 2018. Some seismic sequences in the catalog–such as the 2008 Dallas Fort Worth Airport earthquakes–are well-known and well-studied, while others such as the 2018 west Cleburne sequence are reported in the paper for the first time.

DeShon said publishing the complete catalog was important in part to help people recognize that “there are earthquakes throughout the basin, not just on these three or four sequences that have garnered a lot of press attention.”

The researchers found that overall seismicity in the Fort Worth Basin has been strongly correlated in time and space with wastewater injection activities, with most seismicity occurring within 15 kilometers of disposal wells.

Wastewater disposal volume began to decrease from its peak in 2014, mostly as a result of lower oil and gas prices, and the study showed “tapering off of seismicity along the faults that were near high-injection wells,” said Quinones.

There are exceptions to this pattern, including the 2015 Irving-Dallas and 2017 Lake Lewisville sequences that have no wells within 15 kilometers.

Induced earthquakes occur when wastewater injected back into the ground increases the pore pressure within the rocks and affects stress along faults in surrounding rock layers. In the Fort Worth Basin, these stress changes may propagate far–more than 10 kilometers–from the injection wells, the researchers suggested.

“Injection rates peaked in 2014, but we still don’t understand how spatially extensive the modification of pore pressure is at depth, so we still don’t understand how the hazard is going to reduce with time,” said DeShon.

There are still far fewer induced earthquakes in the Fort Worth Basin compared to regions such as Oklahoma, which also has experienced a dramatic increase in seismicity in the past decade as the result of wastewater disposal from oil and gas production. The volumes of injected wastewater are much higher in Oklahoma, and the faults there tend to be much closer together, DeShon said.

By contrast, Quinones said, faults in the Fort Worth Basin are more widely spaced, and there are few instances of earthquakes jumping between faults.

However, the dense population of the Dallas-Fort Worth metropolitan area makes it critical to continue monitoring the region’s induced earthquake risk, comparing seismic data with more information on wastewater injection.

For the moment, DeShon said, researchers only have access to monthly cumulative volume and average pressure at injection wellheads, in a report that is updated once a year.

“It would be best if injection data were provided in a more timely fashion in Texas, and if more detailed daily information on injection rates and  volumes and some measurements of downhole pressure were provided,” she said.–Seismological Society of America

About SMU

SMU is the nationally ranked global research university in the dynamic city of Dallas. SMU’s alumni, faculty and nearly 12,000 students in seven degree-granting schools demonstrate an entrepreneurial spirit as they lead change in their professions, communities and the world.

 

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New Smithsonian Exhibit Reflects the Passion of SMU Professor and an Army of Student Fossil Hounds

A fossil mosasaur skull and partial skeleton excavated from Angola’s costal cliffs for display in “Sea Monsters Unearthed.” When the South Atlantic ocean basin was still young, a new deep-water connection between the Southern and Northern Hemispheres allowed giant marine reptiles to move into Angola's coastal waters. Mosasaurs and sea turtles, drawn by the region's plentiful food, were among the first reptiles to prowl these waters. “Fossils tell us about the life that once lived on Earth, and how the environments that came before us evolve over time,” said Louis Jacobs, professor emeritus of paleontology at SMU and collaborating curator for the exhibition. “Our planet has been running natural experiments on what shapes environments, and thereby life, for millions of years. If it weren’t for the fossil record, we wouldn’t understand what drives the story of life on our planet.” (Credit: Hillsman S. Jackson, Southern Methodist University)

Sea Monsters Unearthed: Life in Angola’s Ancient Seas opens Nov. 9 at National Museum of Natural History

DALLAS (SMU October 15, 2018) – Once the exhibit opens, “Sea Monsters Unearthed: Life in Angola’s Ancient Seas” will allow visitors to visually dive into the cool waters off the coast of West Africa as they existed millions of years ago when the continents of Africa and South America were drifting apart. It’s a unique opportunity to examine fossils of ancient marine reptiles and learn about the forces that continue to mold life both in out of the ocean.

But the back story is just as fascinating: SMU Emeritus Professor of Paleontology Louis Jacobs and his SMU colleague Michael Polcyn forged a partnership with collaborators in Angola, Portugal and the Netherlands to explore and excavate Angola’s rich fossil history, while laying the groundwork for returning the fossils to the West African nation. Back in Dallas Jacobs and Polcyn, director of the University’s Digital Earth Sciences Lab, and research associate Diana Vineyard went to work over a period of 13 years with a small army of SMU students to prepare the fossils excavated by Projecto PaleoAngola.

The result is a dynamic exhibit opening Nov. 9 in the Smithsonian’s National Museum of Natural History featuring large vertebrate marine reptiles from the Cretaceous Period — mosasaurs, marine turtles and plesiosaurs. This exhibit will mark the first time Angolan fossils of colossal Cretaceous marine reptiles will be on public display.

“It turns out that Angola is the best place on the surface of the earth to see the rocks that reflect and show the opening of the South Atlantic and the split between South America and Africa,” Jacobs said. But the war of independence in Angola that began in 1961 and ended (after civil war) in 2002 effectively prevented scientists from working this rich fossil zone for nearly 40 years after continental drift and plate tectonics became accepted scientific theory.

When Jacobs and the team arrived to begin digging on the coast of Angola in 2005, they were first on the scene to record this fascinating record of sea life that existed as the South Atlantic Ocean grew between two drifting continents.

SMU students did the important, time-consuming lab work

Over the past 13 years, the fossils were shipped back to Dallas, where over 100 undergraduate students have worked in basement laboratories to painstakingly clean and preserve the fossils. Some were paleontology students, most were not – but they seem to share an appreciation for their unique role in sharing new knowledge.

“Getting fossils out of rocks is a time consuming, labor-intensive operation,” Jacobs said. “But every time a student removes a grain of sand off a fossil, they have the excitement of seeing ancient life that no one else in the world has ever seen. On top of that, these fossils are going on exhibit at the Smithsonian and then back to their own homeland. That gives our students an opportunity that they simply could not get anywhere else. And what’s not to like about that?”

The Smithsonian exhibit, made possible by the Sant Ocean Hall Endowment fund, will immerse visitors in a marine environment from the Cretaceous Period, which began about 145 million years ago and ended about 66 million years ago. It features lively animations and vivid paleoart murals of life beneath the waves courtesy of natural history artist (and longtime Jacobs collaborator) Karen Carr. The exhibit brings to life 11 authentic fossils from Angola’s ancient seas, full-size fossil reconstructions of a mosasaur and a marine turtle, as well as 3-D scanned replicas of mosasaur skulls. Photomurals and video vignettes will take visitors to field sites along Angola’s modern rugged coast, where Projecto PaleoAngola scientists unearthed the fossil remains from this lost world.

“Because of our planet’s ever-shifting geology, Angola’s coastal cliffs contain the fossil remains of marine creatures from the prehistoric South Atlantic,” said Kirk Johnson, the Sant Director of the National Museum of Natural History. “We are honored by the generosity of the Angolan people for sharing a window into this part of the Earth’s unfolding story with our visitors.”

About SMU

SMU is the nationally ranked global research university in the dynamic city of Dallas. SMU’s alumni, faculty and nearly 12,000 students in seven degree-granting schools demonstrate an entrepreneurial spirit as they lead change in their professions, communities and the world. For more information, visit SMU on its website and on Facebook and Twitter.

About the National Museum of Natural History

The National Museum of Natural History is connecting people everywhere with Earth’s unfolding story. The museum is one of the most visited natural history museums in the world with approximately 7 million annual visitors from the U.S. and around the world. Opened in 1910, the museum is dedicated to maintaining and preserving the world’s most extensive collection of natural history specimens and human artifacts. It is open daily from 10 a.m. to 5:30 p.m. (closed Dec. 25). Admission is free. For more information, visit the museum on its website and on Facebook and Twitter.

In the words of smu students and graduates who sorted, cleaned and preserved fossils for Projecto Paleoangola

Pictured (L to R): Yasmin Jackson, Tania Doblado Speck, Harrison Schumann and Evan Snyder

Evan Snyder (SMU 2019)

“This experience allowed me to work on a project far bigger than myself. Exhibits just like this one excited me as a young child and led to my study of science. I’d love to think that my work will have the same impact on kids today. Working on this project also taught me how to work on challenging and stressful tasks with the right balance of confidence and care to meet deadlines with quality work.”

Yasmin Jackson (SMU 2019)

“I was able to go to the Smithsonian for the first time through this project. I really liked being able to see all of the different exhibits that are currently in the museum and imagine what our exhibit will be like in the midst of all of it.”

Harrison Schuman (SMU 2019)

“Dr. Jacobs is an inspiring individual to be around. Despite being a world-class expert in paleontology, he made himself very approachable and was always personally invested in all of the students working on the project. This kind of attitude encourages students like me to pursue careers in science.”

Alexandra Lippas (SMU 2011)

“It is because of Dr. Jacobs that I was able to be a part of this project. He encouraged students from other branches of science to work on this study. I think it demonstrates that different perspectives can lead to great discovery.”

Connor Flynn (SMU 2014)

“My time in the lab will be a source of stories for years to come and a point of pride for a lifetime. Its lessons in patience, care and passion for the labor will never be forgotten. Dr. Jacobs’ words ‘There’s nothing so broken you can’t fix it,’ carried me through more lab accidents than i care to admit — both at SMU and beyond.”

Jennifer Welch (SMU 2019)

“Dr. Jacobs is so incredibly smart, I could point out any part of the vertebrae and he would tell me what it’s for, why it was there, how that impacted the life of the animal and the stories that told about the land where the animal lived.”

Stephen Tyler Armstrong (SMU 2012)

“As an engineering major, this project exposed me to areas of research and career paths I would otherwise not encountered. It was really interesting to work so closely with those conducting the research to learn about a subject outside of my realm.”

For more information about undergraduate students working in SMU’s earth sciences labs.

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Native Bison Hunters Amplified Climate Impacts on North American Prairie Fires

Blackfeet Burning Crow Buffalo Range, painting by Charles Marion Russell, 1905.
Blackfeet Burning Crow Buffalo Range, painting by Charles Marion Russell, 1905.

Study shows hunter-gatherers used active burning to improve grazing, drive bison, long before arrival of Columbus

Blackfeet Burning Crow Buffalo Range, painting by Charles Marion Russell, 1905.
Blackfeet Burning Crow Buffalo Range, painting by Charles Marion Russell, 1905.

DALLAS (SMU) – Native American communities actively managed North American prairies for centuries before Christopher Columbus’ arrival in the New World, according to a new study led by Southern Methodist University (SMU) archaeologist Christopher I. Roos.

Fire was an important indigenous tool for shaping North American ecosystems, but the relative importance of indigenous burning versus climate on fire patterns remains controversial in scientific communities. The new study, published in Proceedings of the National Academy of Sciences (PNAS), documents the use of fire to manipulate bison herds in the northern Great Plains. Contrary to popular thinking, burning by indigenous hunters combined with climate variability to amplify the effects of climate on prairie fire patterns.

The relative importance of climate and human activities in shaping fire patterns is often debated and has implications for how we approach fire management today.

“While there is little doubt that climate plays an important top-down role in shaping fire patterns, it is far less clear whether human activities – including active burning – can override those climate influences,” said Roos. “Too often, if scientists see strong correlations between fire activity and climate, the role of humans is discounted.”

Anthropologists and historians have documented a wide variety of fire uses by Native peoples in the Americas but fire scientists have also documented strong fire-climate relationships spanning more than 10,000 years.

“People often think that hunter-gatherers lived lightly on the land,” said Kacy L. Hollenback, an anthropologist at SMU and co-author of the study. “Too often we assume that hunter-gatherers were passive in their interaction with their environment. On the Great Plains and elsewhere, foragers were active managers shaping the composition, structure, and productivity of their environments. This history of management has important implications for contemporary relationships between Native American and First Nations peoples and their home landscapes – of which they were ecosystem engineers.”

Working in partnership with the Blackfeet Tribe in northern Montana, Roos and colleagues combined landscape archaeology and geoarchaeology to document changes in prairie fire activity in close spatial relationship to stones piled in formations up to a mile long that were used to drive herds of bison off of cliffs to be harvested en masse. These features are known as drivelines.

“We surveyed the uplands for stone features that delineate drivelines within which bison herds would be funneled towards a jump,” said anthropologist María Nieves Zedeño of the University of Arizona, co-author of the study. “By radiocarbon dating prairie fire charcoal deposits from the landscape near the drivelines, we were able to reconstruct periods of unusually high fire activity that are spatially associated with the drivelines,” says Roos.

The overlap between peak periods of driveline use (ca. 900-1650 CE) and prairie fire activity (ca. 1100-1650 CE) suggests that fire was an important tool in the hunting strategy involving the drivelines. Roos and colleagues suggest that fire was used to freshen up the prairie near the mouth of the drivelines to attract herds of bison, who prefer to graze recently burned areas. Episodes of high fire activity also correspond to wet climate episodes, when climate would have produced abundant grass fuel for prairie fires.

The absence of deposits indicating high prairie fire activity before or after the period of driveline use, even though comparable wet climate episodes occurred, suggests that anthropogenic burning by Native hunters amplified the climate signal in prairie fire patterns during the period of intensive bison hunting.

“We need to consider that humans and climate have more complicated and interacting influences on historical fire patterns,” said Roos. “Moreover, we need to acknowledge that hunter-gatherers can be active influences in their environments, particularly through their use of fire as a landscape tool. We expect that future studies of human/climate/fire interactions will further document the complexity of these relationships. Understanding that complexity may prove important as we try to navigate the complex wildfire problems we face today.”

About SMU

SMU is a nationally ranked global research university in the dynamic city of Dallas. SMU’s alumni, faculty and nearly 12,000 students in seven degree-granting schools demonstrate an entrepreneurial spirit as they lead change in their professions, communities and the world.

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Ancient “Sea Monsters” Reveal How the Ever-Changing Planet Shapes Life, Past and Present

Never-Before-Seen Fossils From Angola Bring a Strange Yet Familiar Ocean Into View

The Smithsonian’s National Museum of Natural History will open a new exhibition Nov. 9, 2018 revealing how millions of years ago, large-scale natural forces created the conditions for real-life sea monsters to thrive in the South Atlantic Ocean basin shortly after it formed. “Sea Monsters Unearthed: Life in Angola’s Ancient Seas” will offer visitors the opportunity to dive into Cretaceous Angola’s cool coastal waters, examine the fossils of striking marine reptiles that once lived there and learn about the forces that continue to mold life in the ocean and on land.

Over 134 million years ago, the South Atlantic Ocean basin did not yet exist. Africa and South America were one contiguous landmass on the verge of separating. As the two continents drifted apart, an entirely new marine environment — the South Atlantic — emerged in the vast space created between them. This newly formed ocean basin would soon be colonized by a dizzying array of ferocious predators and an abundance of other lifeforms seizing the opportunity presented by a new ocean habitat.

“Because of our planet’s ever-shifting geology, Angola’s coastal cliffs contain the fossil remains of marine creatures from the prehistoric South Atlantic,” said Kirk Johnson, the Sant Director of the museum. “We are honored by the generosity of the Angolan people for sharing a window into this part of the Earth’s unfolding story with our visitors.”

For the first time, Angolan fossils of colossal Cretaceous marine reptiles will be on public display. Through Projecto PaleoAngola — a collaboration between Angolan, American, Portuguese and Dutch researchers focused on Angola’s rich fossil history — paleontologists excavated and studied these fossils, which were then prepared for the exhibition by a team of scientists and students at Southern Methodist University (SMU) in Dallas. The exhibition was made possible by the Sant Ocean Hall Endowment Fund.

“Fossils tell us about the life that once lived on Earth, and how the environments that came before us evolve over time,” said Louis Jacobs, professor emeritus of paleontology at SMU and collaborating curator for the exhibition. “Our planet has been running natural experiments on what shapes environments, and thereby life, for millions of years. If it weren’t for the fossil record, we wouldn’t understand what drives the story of life on our planet.”

The exhibition will immerse visitors in this Cretaceous environment with lively animations and vivid paleoart murals of life beneath the waves — courtesy of natural history artist Karen Carr — that bring to life 11 authentic fossils from Angola’s ancient seas, full-size fossil reconstructions of a mosasaur and an ancient sea turtle, as well as 3-D scanned replicas of mosasaur skulls. Photomurals and video vignettes will transport visitors to field sites along Angola’s modern rugged coast, where Projecto PaleoAngola scientists unearth the fossil remains from this lost world.

A Strange but Familiar Ocean
“Sea Monsters Unearthed” paints the picture of a flourishing ocean environment that in some ways will look strange to modern eyes, yet still bears striking similarities to today’s marine ecosystems.

Peculiar plesiosaurs — massive reptiles with long necks, stout bodies and four large flippers — swam alongside 27-foot-long toothy marine lizards called mosasaurs and more familiar creatures like sea turtles. From surprising mosasaur stomach contents to the one of the oldest known sea turtles found in Africa, fossils and reconstructions of these species will offer visitors a fuller picture of their remarkable life histories and the ecosystems they were a part of.

The exhibition will also explore deeper similarities across the ecology and anatomy of ocean animals then and now. After the marine reptiles that dominated these waters went extinct 66 million years ago, modern marine mammals would not only later replace them as top predators in the world’s ocean, but also converge on many of the same body shapes and survival strategies.

The Forces That Shape Life, Then and Now
This unique period in Earth’s history reveals how key geologic and environmental forces contributed to the early establishment and evolution of life in the South Atlantic. As Africa and South America drifted apart and a new ocean basin formed, trade winds blowing along the new Angolan coastline created the conditions for upwelling, an ocean process that drives the circulation of nutrients from the deep ocean to its surface. These nutrients in turn jump-started the food web that attracted the ferocious marine reptile predators featured throughout the exhibition.

Just as tectonic forces helped create this Cretaceous marine environment, they also shaped the arid coastal cliffs where the fossils are found today. Starting 45,000 years ago, a geologic process called uplift caused Earth’s crust to bulge along Angola’s coast, lifting part of the seafloor out of the water — and along with it, the layers upon layers of fossil-filled rocks where Projecto PaleoAngola scientists work.

Though humans do not operate on a tectonic scale, their actions also have major impacts on ocean life. Humans are now the ocean’s top predators, with one-fifth of the world’s population relying on food from upwelling-based ecosystems. Scientists caution that with such great pressure on modern upwelling-based fisheries, overfishing could change the future of life in the ocean by threatening fish populations, marine ecosystems and even human health. — National Museum of Natural History

About the National Museum of Natural History
The National Museum of Natural History is connecting people everywhere with Earth’s unfolding story. The museum is one of the most visited natural history museums in the world with approximately 7 million annual visitors from the U.S. and around the world. Opened in 1910, the museum is dedicated to maintaining and preserving the world’s most extensive collection of natural history specimens and human artifacts. It is open daily from 10 a.m. to 5:30 p.m. (closed Dec. 25). Admission is free. For more information, visit the museum on its website and on Facebook and Twitter.