Nav: Home

UMass Amherst geoscientists offer new evidence for how the Adirondack Mountains formed

June 26, 2018

AMHERST, Mass. - The formation mechanism of the Adirondack Mountains in upstate New York has long posed a geologic mystery, say seismology researchers at the nearby University of Massachusetts Amherst. A few have been proposed, but until recently tools for evaluating them were not in place, say postdoctoral fellow Xiaotao Yang and assistant professor Haiying Gao.

Now, using an advanced seismic imaging method and data available only in the past five years, they have constructed a detailed model of the tectonic plate - the crust and the uppermost rigid mantle of the lithosphere under the northeast United States - down to about 62 miles (100 km), in which they discovered a "pillow" of low-density, relatively light rock material. They say a column of this lighter material appears to have squeezed up under the Adirondacks, possibly expanded by heat, to form the dome-shaped mountains.

"For the first time, we have some direct evidence of structures beneath the Adirondack Mountains, and we show that this feature and a past period of uplift are connected to a much larger-scale, regional situation," Yang says.

"We propose that geologic processes triggered the flow of this lower density, relatively light and buoyant low-velocity material from a large reservoir into a fracture or a vacant space and it accumulated there in a column and was lifted up. It also may have been hot and thermally expanded." Details appear in the American Geophysical Union journal, Geophysical Research Letters.

One way the researchers can differentiate this pillow and column of anomalous material is by measuring the speed of seismic waves traveling through the Earth, Yang explains. "Seismic waves travel more slowly through the low-density, low-velocity material compared to surrounding rocks."

He and Gao mapped this low-velocity material at about 31 to 52 miles (50-85 km) beneath the Adirondack Mountains. "These low-speed features may have resulted from the rising of asthenosphere, a weak layer beneath the lithosphere," the researchers note. "The upward force of the upwelling asthenosphere flow, together with possible thermal expansion, may have provided the mechanism that formed the Adirondack Mountains."

The question of how different mountains formed has been around for many years, Yang says, and for very large features such as the 1,500-mile Appalachian Mountain range, tectonic plate boundary collision processes are relatively well understood. But for mountains that lie entirely within one fairly stable tectonic plate, known as intercratonic mountains, uplift mechanisms that are not boundary related, are less clear.

"We want to know more about the formation of this kind of mountains," Yang says. "Before this study, we suspected that the plate is being pushed up from below to form a dome, but there was no evidence for or against this idea."

For this work, he and Gao used data from the National Science Foundation's EarthScope program, a portable array of seismometers deployed across the U.S. and moved systematically from west to east over a number of years in the Lower 48 states. Data in the northeastern U.S. has been publicly available since 2013. Before EarthScope, collecting such data was "hit or miss," Yang says, because seismometers were unevenly and sparsely distributed.

"EarthScope provided much finer data coverage," he adds. "It provided a really unique opportunity to allow us to conduct this study, not only because of the density of stations, but they were evenly distributed which gave us more of a 3D understanding of the features. To get a clearer picture, we exploited an advanced technique, involving simulation of seismic waves propagating in 3D Earth."

"Instead of using earthquake waves, our technique extracts seismic waves from background noises between each two stations, taking advantage of the densely distributed seismic stations. You also need a way to handle the process of a huge amount of data," he adds. For this, they used the Massachusetts Green High Performance Computing Center in Holyoke, Massachusetts.

Based on their observations, he and Gao now believe that between 90 and 120 million years ago, the tectonic plate under the northeastern U.S. was passing over a geologic "hot spot," which is now under the western Atlantic Ocean, off the coast of Massachusetts, known as the New England seamounts. Some studies suggest that the New England region was uplifting at around that time, which could have resulted from hot spot heating. The hot-spot activities may also have contributed heat to processes forming the Adirondack Mountains.

In addition to funding from NSF and NSF's EarthScope program, this work was supported by start-up funding from UMass Amherst to Gao's seismology laboratory.

University of Massachusetts at Amherst

Related Data Articles:

Ups and downs in COVID-19 data may be caused by data reporting practices
As data accumulates on COVID-19 cases and deaths, researchers have observed patterns of peaks and valleys that repeat on a near-weekly basis.
Data centers use less energy than you think
Using the most detailed model to date of global data center energy use, researchers found that massive efficiency gains by data centers have kept energy use roughly flat over the past decade.
Storing data in music
Researchers at ETH Zurich have developed a technique for embedding data in music and transmitting it to a smartphone.
Life data economics: calling for new models to assess the value of human data
After the collapse of the blockchain bubble a number of research organisations are developing platforms to enable individual ownership of life data and establish the data valuation and pricing models.
Geoscience data group urges all scientific disciplines to make data open and accessible
Institutions, science funders, data repositories, publishers, researchers and scientific societies from all scientific disciplines must work together to ensure all scientific data are easy to find, access and use, according to a new commentary in Nature by members of the Enabling FAIR Data Steering Committee.
Democratizing data science
MIT researchers are hoping to advance the democratization of data science with a new tool for nonstatisticians that automatically generates models for analyzing raw data.
Getting the most out of atmospheric data analysis
An international team including researchers from Kanazawa University used a new approach to analyze an atmospheric data set spanning 18 years for the investigation of new-particle formation.
Ecologists ask: Should we be more transparent with data?
In a new Ecological Applications article, authors Stephen M. Powers and Stephanie E.
Should you share data of threatened species?
Scientists and conservationists have continually called for location data to be turned off in wildlife photos and publications to help preserve species but new research suggests there could be more to be gained by sharing a rare find, rather than obscuring it, in certain circumstances.
Futuristic data storage
The development of high-density data storage devices requires the highest possible density of elements in an array made up of individual nanomagnets.
More Data News and Data Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: The Power Of Spaces
How do spaces shape the human experience? In what ways do our rooms, homes, and buildings give us meaning and purpose? This hour, TED speakers explore the power of the spaces we make and inhabit. Guests include architect Michael Murphy, musician David Byrne, artist Es Devlin, and architect Siamak Hariri.
Now Playing: Science for the People

#576 Science Communication in Creative Places
When you think of science communication, you might think of TED talks or museum talks or video talks, or... people giving lectures. It's a lot of people talking. But there's more to sci comm than that. This week host Bethany Brookshire talks to three people who have looked at science communication in places you might not expect it. We'll speak with Mauna Dasari, a graduate student at Notre Dame, about making mammals into a March Madness match. We'll talk with Sarah Garner, director of the Pathologists Assistant Program at Tulane University School of Medicine, who takes pathology instruction out of...
Now Playing: Radiolab

What If?
There's plenty of speculation about what Donald Trump might do in the wake of the election. Would he dispute the results if he loses? Would he simply refuse to leave office, or even try to use the military to maintain control? Last summer, Rosa Brooks got together a team of experts and political operatives from both sides of the aisle to ask a slightly different question. Rather than arguing about whether he'd do those things, they dug into what exactly would happen if he did. Part war game part choose your own adventure, Rosa's Transition Integrity Project doesn't give us any predictions, and it isn't a referendum on Trump. Instead, it's a deeply illuminating stress test on our laws, our institutions, and on the commitment to democracy written into the constitution. This episode was reported by Bethel Habte, with help from Tracie Hunte, and produced by Bethel Habte. Jeremy Bloom provided original music. Support Radiolab by becoming a member today at     You can read The Transition Integrity Project's report here.