https://www.geol.umd.edu/facilities/seismology/News and research notes from the Lekić Lab, University of Maryland https://www.geol.umd.edu/facilities/seismology/a-molten-layer-above-marss-core/https://www.geol.umd.edu/facilities/seismology/a-molten-layer-above-marss-core/Thu, 30 Jul 2026 14:06:55 +0000When we publish papers, we hope they can get read, cited, or even built upon. It’s rare that a paper gets argued with in print and at length, which is probably a sign that the paper was worth writing! A couple of years ago, Henri Samuel, at the Institut de Physique du Globe de Paris,https://www.geol.umd.edu/facilities/seismology/the-gradiometer-has-finite-size/https://www.geol.umd.edu/facilities/seismology/the-gradiometer-has-finite-size/Tue, 28 Jul 2026 16:52:58 +0000There are something like a hundred million unexploded landmines and pieces of ordnance in the ground worldwide, most of them small, shallow, and made of enough metal to have a magnetic signature. But reliably finding them with a magnetometer is far from easy. Heidi Myers, a former Ph.D. student co-advised by myself and Prof. Danhttps://www.geol.umd.edu/facilities/seismology/a-method-built-for-mars-focused-back-onto-the-moon/https://www.geol.umd.edu/facilities/seismology/a-method-built-for-mars-focused-back-onto-the-moon/Tue, 28 Jul 2026 13:46:42 +0000On Earth, a straightforward way of measuring the thickness of the crust beneath a seismometer is to look for converted waves — a P wave that turns into an S wave at the crust-mantle boundary. The method is simple, reliable, and used everywhere. On the Moon it has never really worked for P-to-S conversions. Apollohttps://www.geol.umd.edu/facilities/seismology/an-iron-rich-root-beneath-hawaii/https://www.geol.umd.edu/facilities/seismology/an-iron-rich-root-beneath-hawaii/Mon, 27 Jul 2026 21:57:25 +0000Sitting at the very base of the mantle, directly beneath Hawai’i, is a patch of rock where seismic waves slow down dramatically. Structures like this — ultralow-velocity zones, or ULVZs — are found in many places along the core-mantle boundary, but the ones beneath major hot spots are exceptionally large, and their origin has beenhttps://www.geol.umd.edu/facilities/seismology/when-the-average-isnt-a-solution/https://www.geol.umd.edu/facilities/seismology/when-the-average-isnt-a-solution/Mon, 27 Jul 2026 21:57:16 +0000Bayesian sampling methods have entered the geophysical toolkit due to their versatility and power at quantifying uncertainty. Our lab has spent a decade contributing to them: transdimensional deconvolution of receiver functions, self-parameterizing inversions of surface waves, Bayesian tomography of North America and the inner core, etc. Regardless of the specific application, these methods return nothttps://www.geol.umd.edu/facilities/seismology/rehearsing-for-the-moon/https://www.geol.umd.edu/facilities/seismology/rehearsing-for-the-moon/Mon, 27 Jul 2026 21:30:28 +0000Three papers led by Jingchuan Wang (formerly a postdoc at Maryland, currently at Caltech) appeared in 2025 — one in JGR: Planets, one in Geophysical Research Letters, one in Earth and Space Science. They describe fieldwork at sites hundreds of miles apart and they read, at first glance, like three separate projects. But, all threehttps://www.geol.umd.edu/facilities/seismology/a-hidden-fault-and-missing-aftershocks-beneath-delaware-bay/https://www.geol.umd.edu/facilities/seismology/a-hidden-fault-and-missing-aftershocks-beneath-delaware-bay/Mon, 27 Jul 2026 20:48:03 +0000Eight years ago, the day after a magnitude 4.2 earthquake struck east of Dover, Delaware, graduate students from this lab were in the field installing seismometers alongside collaborators from the Carnegie Institution for Science, the Delaware Geological Survey, the U.S. Geological Survey, Lehigh University, and the Lamont-Doherty Earth Observatory. That deployment has now produced itshttps://www.geol.umd.edu/facilities/seismology/constraints-on-martian-core-from-first-observations-of-sks-waves/https://www.geol.umd.edu/facilities/seismology/constraints-on-martian-core-from-first-observations-of-sks-waves/Mon, 24 Apr 2023 19:36:29 +0000Mars has a liquid iron alloy core at its center. Using seismic data gathered by the InSight mission, we have made the first observations of seismic waves traveling through Mars’ core. We use the travel times of core-transiting seismic waves, relative to ones which remain in the mantle, to constrain properties of the core andhttps://www.geol.umd.edu/facilities/seismology/congratulations-to-prof-ross-maguire/https://www.geol.umd.edu/facilities/seismology/congratulations-to-prof-ross-maguire/Wed, 06 Apr 2022 18:23:45 +0000We wish Prof. Ross Maguire all the best as he transitions to his new position as an Assistant Professor at the University of Illinois, Urbana-Champaign!https://www.geol.umd.edu/facilities/seismology/dr-doyeon-kim-takes-an-oberassistent-position-at-eth-zurich/https://www.geol.umd.edu/facilities/seismology/dr-doyeon-kim-takes-an-oberassistent-position-at-eth-zurich/Thu, 14 Oct 2021 15:18:19 +0000Congratulations to Dr. Doyeon (DK) Kim, who has taken an Oberassistent position at the Swiss Federal Institute of Technology (ETH) in Zurich. We wish him the best of luck and look forward to many years of collaboration.https://www.geol.umd.edu/facilities/seismology/dr-pritwiraj-moulik-becomes-associate-research-scholar-at-princeton-university/https://www.geol.umd.edu/facilities/seismology/dr-pritwiraj-moulik-becomes-associate-research-scholar-at-princeton-university/Wed, 13 Oct 2021 15:27:02 +0000We wish Pritwiraj (Raj) Moulik the best of luck in his new position as Associate Research Scholar at Princeton University!https://www.geol.umd.edu/facilities/seismology/dr-kristel-izquierdo-moves-to-purdue-university/https://www.geol.umd.edu/facilities/seismology/dr-kristel-izquierdo-moves-to-purdue-university/Tue, 14 Sep 2021 15:41:37 +0000After successfully defending her Ph.D. dissertation, Dr. Izquierdo has moved to Purdue University where she will be a postdoc in their Planetary Science group. We wish Kris the best of luck and lots of exciting discoveries!https://www.geol.umd.edu/facilities/seismology/dr-chao-gao-moves-to-houston/https://www.geol.umd.edu/facilities/seismology/dr-chao-gao-moves-to-houston/Mon, 25 Nov 2019 01:57:46 +0000We wish Chao the best of luck in his new position at CGG in Houston, TX.https://www.geol.umd.edu/facilities/seismology/dr-erin-cunningham-begins-postdoc-at-ceri/https://www.geol.umd.edu/facilities/seismology/dr-erin-cunningham-begins-postdoc-at-ceri/Mon, 25 Nov 2019 01:56:27 +0000We wish Erin the best of luck as she ventures on the next step of her scientific journey as a postdoc at CERI!https://www.geol.umd.edu/facilities/seismology/spurious-low-velocity-zones-in-joint-inversions-of-surface-waves-and-receiver-functions/https://www.geol.umd.edu/facilities/seismology/spurious-low-velocity-zones-in-joint-inversions-of-surface-waves-and-receiver-functions/Mon, 25 Nov 2019 01:49:12 +0000Low-velocity layers within the crust can indicate the presence of melt and lithologic differences with implications for crustal composition and formation. Seismic wave conversions and reverberations across the base of the crust or intracrustal discontinuities, analysed using the receiver function method, can be used to constrain crustal layering. This is commonly accomplished by inverting receiverhttps://www.geol.umd.edu/facilities/seismology/first-tomographic-model-of-the-inner-core/https://www.geol.umd.edu/facilities/seismology/first-tomographic-model-of-the-inner-core/Mon, 25 Nov 2019 01:20:24 +0000With collaborators Scott Burdick at Wayne State University and Lauren Waszek at New Mexico State University — both former Maryland postdocs — we just published the first tomographic model of Earth’s inner core in Earth and Planetary Science Letters. Seismic body wave and normal mode analyses have revealed that the inner core is solid, stronglyhttps://www.geol.umd.edu/facilities/seismology/improved-model-of-outer-core-1d-structure/https://www.geol.umd.edu/facilities/seismology/improved-model-of-outer-core-1d-structure/Tue, 10 Jul 2018 18:47:46 +0000We have published a new model of 1D structure of the outer core, parameterized using two different equations of state: Irving_Cottaar_Lekic_2018 Brief highlights: We infer the seismic properties and equation of state of the outer core using Earth’s oscillations We address a longstanding discrepancy between high and low frequency investigations of the outer core Our workhttps://www.geol.umd.edu/facilities/seismology/prof-olugboji-moves-to-u-rochester/https://www.geol.umd.edu/facilities/seismology/prof-olugboji-moves-to-u-rochester/Tue, 10 Jul 2018 18:37:55 +0000We wish Prof. Olugboji the very best of luck as he starts his new position of Assistant Professor at the University of Rochester.https://www.geol.umd.edu/facilities/seismology/our-paper-about-the-properties-of-the-outer-core-is-published-in-science-advances/https://www.geol.umd.edu/facilities/seismology/our-paper-about-the-properties-of-the-outer-core-is-published-in-science-advances/Wed, 27 Jun 2018 21:54:59 +0000Link to the article: http://advances.sciencemag.org/content/4/6/eaar2538 Link to a nice write-up about how the project came together: https://www.princeton.edu/news/2018/06/27/seismologist-jessica-irving-uses-massive-earthquakes-unlock-secrets-outer-corehttps://www.geol.umd.edu/facilities/seismology/congratulations-to-tolu/https://www.geol.umd.edu/facilities/seismology/congratulations-to-tolu/Fri, 06 Apr 2018 17:42:17 +0000We congratulate Dr. Tolu Olugboji for being selected a Fellow of the Next Einstein Forum, which recognises Africa’s best young scientists and technologists. In March, Tolu presented his research in Kilagi, Rwanda. Check out the photos from the ceremony, below.