University of Illinois at Urbana-Champaign
Jan 2021 - Jun 2021
Jan 2019 - Dec 2019
Aug 2017 - Mar 2019
4-D Geodynamic Modeling With Data Assimilation: Origin Of Intra-Plate Volcanism In The Pacific Northwest(gk6)
Aug 2017 - Jul 2018
Sep 2015 - Aug 2017
4-D Geodynamic Modeling with Data Assimilation: Origin of Intra-Plate Volcanism in the Pacific Northwest(giv)
May 2015 - May 2016
May 2013 - Nov 2014
Blue Waters Symposium 2019, Jun 5, 2019
Blue Waters Symposium 2018, Jun 5, 2018
Blue Waters Symposium 2017, May 18, 2017
Lijun Liu: Simulating 4-D Subduction and Mantle Flow beneath the Americas using Data Assimilation Models
Blue Waters Symposium 2016, Jun 14, 2016
Feb 19, 2018
The researchers processed geophysical data with the Blue Waters supercomputer at the National Center for Supercomputing Applications at Illinois hoping to better understand these high-elevation regions. The thick roots of cratons have been thought to be buoyant due to their low-density mineral content, allowing them to float on top of the hot underlying mantle. However, the new data indicate that the cold mantle that lies below these regions in South America and Africa – once joined as part of the supercontinent Pangea – has a layered structure and that the lower layer was more dense in the past than it is today.
Dec 18, 2017
The origin of late Cenozoic intraplate volcanism over the western United States is debated. One important reason is the lack of a clear understanding of the mantle dynamics during this volcanic history. Here we reconstruct the mantle thermal states beneath North America since 20 million years ago using a hybrid inverse geodynamic model with data assimilation. The model simultaneously satisfies the past subduction kinematics, present mantle tomographic image and the volcanic history. We find that volcanism in both the Yellowstone volcanic province and the Basin and Range province corresponds to a similar eastward-intruding mantle derived from beneath the Pacific Ocean and driven mostly by the sinking Farallon slab below the central-eastern United States.
May 26, 2017
Contrary to posters you may have seen hanging on the walls in science buildings and classrooms, Lijun Liu, professor of geology at Illinois, knows that Earth's interior is not like an onion. While most textbooks demonstrate the outer surface of the Earth as the crust, the next inner level as the mantle, and then the most inner layer as the core, Liu said the reality isn't as clear-cut.
Nov 21, 2016
Scientists may be a step closer to predicting volcanic activity and earthquakes thanks to research conducted using the Blue Waters supercomputer. University of Illinois at Urbana-Champaign geology professor Lijun Liu and his collaborator Derrick Hasterok at the University of Adelaide in Australia ran models of 100 cores each on Blue Waters to help them develop a method to estimate weakness in the Earth’s outer layers.
Oct 3, 2016
The researchers developed a method for measuring strength and finding weak spots in the lithosphere, the outer layers of earth that include the crust and the outer mantle -- the molten rock lurking just under the surface that can well up and create volcanoes. The researchers found that calculating lithosphere strength using magnetotelluric imaging maps of the southwestern United States can more accurately describe the rough terrain and volcanic and seismic activity observed on the surface than can standard geologic models. The study by U. of I. geology professor Lijun Liu and Adelaide professor Derrick Hasterok is reported in the journal Science.
Mar 7, 2016
Simmering deep below the geysers and hot springs of the Yellowstone caldera is a dormant supervolcano—a powerful behemoth with the ability to blanket the western U.S. with many centimeters of ash in a matter of hours. What could spark such a powerful eruption? Scientists have long debated over the origins of Yellowstone’s supervolcano, with the most widely accepted idea suggesting that it was formed by a mantle plume—a column of hot rocks emerging from deep within our planet, in the mantle layer. But a new simulation shows that the conventional wisdom was wrong. The plume could not have reached the surface because it was blocked by a slab from an ancient tectonic plate. ... The simulation results of the model, which is the first to replicate the complex interaction between a mantle plume and a sinking slab, was detailed last month in Geophysical Research Letters. Lijun Liu, a geologist at the University of Illinois at Urbana–Champaign, and his graduate student Tiffany Leonard built the model to replicate both the plate tectonic history of the surface and the geophysical image of Earth’s interior.
Feb 17, 2016
The Old Faithful geyser at Yellowstone National Park has thrilled park visitors for over a century, but it wasn’t until this year that scientists figured out the geophysical factors powering it. With over 2 million visitors annually, Yellowstone remains one of the most popular nature destinations in the US. Spanning an area of almost 3,500 square miles, the park sits atop the Yellowstone Caldera. This caldera is the largest supervolcano in North America, and is responsible for the park’s geothermal activity. Until last week, most geologists had explained this activity with the so-called mantle plume hypothesis. This elegant theory proposed an idealized situation where hot columns of mantle rock rose from the core-mantle boundary all the way to the surface, fueling the supervolcano and the geothermal geysers. This theory didn’t sit well with Lijun Liu, assistant professor in the department of Geology at the University of Illinois, however.
Feb 10, 2016
Understanding the complex geological processes that form supervolcanoes could ultimately help geologists determine what triggers their eruptions. A new study using an advanced computer model casts doubt on previously held theories about the Yellowstone supervolcano’s origins, adding to the mystery of Yellowstone’s formation. “Our model covered the entire history of Yellowstone volcanic activities,” said Lijun Liu, a geology professor at the University of Illinois. Liu’s computer model accounted for the last 40 million years, prior to even the earliest signs of Yellowstone’s volcanism.
Jun 10, 2015
Seventeen U of I research teams from a wide range of disciplines have been awarded computational and data resources on the sustained-petascale Blue Waters supercomputer at NCSA. “These diverse projects highlight the breadth of computational research at the University of Illinois,” said Athol Kemball, associate professor of Astronomy and chair of the Illinois allocation review committee. “Illinois has a tremendous pool of talented researchers in fields from political science to chemistry to engineering who can harness the power of Blue Waters to discover and innovate.”
May 2, 2014
Normal procedure for running a job on Blue Waters goes something like this: compile the code; create an executable; write a submission script; submit the script; and the scheduler runs the script. The script specifies how many nodes to run on, and the scheduler allocates resources on the machine. Once the job is launched, it will run on whatever nodes are set aside for that job. When it comes to running jobs using community codes—which are complex in their structure but all-purpose in their construction and execution—things can get tricky, especially when using a code for the first time on a new machine. For Lijun Liu, self-proclaimed geodynamicist in training and computational geologist at the University of Illinois at Urbana-Champaign, this is the very challenge he ran into when first attempting to use a community code on the Blue Waters supercomputer—which he hopes to use in the study of large-scale deformation of the earth through numerical simulations.
Jun 11, 2013
The University of Illinois at Urbana-Champaign has awarded access to the Blue Waters supercomputer—which is capable of performing quadrillions of calculations every second and of working with quadrillions of bytes of data—to 22 campus research teams from a wide range of disciplines. The computing and data capabilities of Blue Waters, which is operated by the National Center for Supercomputing Applications (NCSA), will assist researchers in their work on understanding DNA, developing biofuels, simulating climate, and more.