Category Archives: UMD

University of Maryland geology department

UMD: Carnegie’s Bardyn on comet dust

2018 Geology Colloquium Series

Friday, April 27th 2018 at 3:00 pm
in PLS 1140, University of Maryland, College Park

Anaïs Bardyn
Department of Terrestrial Magnetism, Carnegie Institution for Science

The dust of comet 67P/Churyumov-Gerasimenko

After a 10-year journey, the European spacecraft Rosetta arrived at comet 67P/Churyumov-Gerasimenko (67P) on August 6, 2014. In order to conduct intensive research for 26 months, a total of 21 instruments were on board the Rosetta orbiter and the Philae lander. The mass spectrometer named COSIMA (Cometary Secondary Ion Mass Analyzer) was one of the orbiter instrument and was designed to collect cometary dust particles ejected from 67P nucleus, imaged them and analyzed in situ their composition. I will present the Rosetta space mission, as well as results from the COSIMA instrument regarding the organic content of the cometary dust particles.

Advertisements

UMD Science on Tap: Tom Holtz on T. Rex

A new monthly lecture series at UMD that explores the latest discoveries in science and technology in a relaxed atmosphere with food and drink

T-Rex Skull
The Life &
Death of
T. REX
New discoveries about the most famous dinosaur and the end of
its world
Thomas Holtz
Vertebrate Paleontologist and
UMD Department of Geology
Principal Lecturer

Wednesday, February 28, 2018
Doors open at 6 p.m.
Lecture begins at 6:30 p.m.

Milkboy Art House

MilkBoy ArtHouse
7416 Baltimore Ave.
College Park, MD 20740
(Directions)

RSVP at go.umd.edu/scienceontap
Space is limited. Food and beverages will be available for purchase.

Questions? Contact Abby Robinson at
abbyr@umd.edu or 301-405-5845.


ABOUT THE TALK
Tyrannosaurus rex is arguably the most famous of all dinosaur species. Since its naming in 1905, it has been a cultural and scientific icon. But new discoveries continue to be made about this last and (presently) largest of the giant carnivorous dinosaurs. New specimens and new analytical techniques have revealed details previously unknown about its biology. How did it feed? How did it move? Was it scaly, fuzzy or both? How much and how fast did it grow? How long did it live? And what were those little arms for, anyway? Dr. Holtz will discuss new insights into the biology of T. rex, as well as some of the geological evidence concerning the great extinction which ended the reign of the Tyrant King.

UMD: Boehnke on geochemical models through time

2018 University of Maryland Geology Colloquium Series

Friday, February 9th 2018 at 3:00 pm
in PLS 1140, UMD College Park

Patrick Boehnke
University of Chicago

Getting more out of geochemical data: Models for the Hadean to the Pleistocene

UMD: Jackson on core formation

2018 University of Maryland Geology Colloquium Series

Friday, January 26th 2018 at 3:00 pm
in PLS 1140

Colin Jackson
Smithsonian Institution

Early episodes of high-pressure core formation preserved in plume mantle

UMD: Boise State’s Kohn on Shear heating in subduction zones

2017 University of Maryland Geology Colloquium Series

Friday, November 17th 2017 at 3:00 pm
in PLS 1130, College Park campus

Matthew Kohn
Boise State University

Shear heating controls mineralogy, seismicity, and convection in subduction zones

Popular thermal-mechanical models of modern subduction systems are c. 300 °C colder at c. 50 km depth – the seismic-aseismic transition – than pressure-temperature conditions determined from exhumed metamorphic rocks, i.e. “Rocks are hotter than models” (Penniston-Dorland et al., 2015, EPSL). Subduction zone thermal structure is crucial for predicting depths of seismicity, fluid release, and sub-arc melting conditions. In this talk I will show that adding realistic shear stresses to thermal models quantitatively reproduces surface heat flow and the pressure-temperature conditions recorded by exhumed metamorphic rocks. A consistent seismic-aseismic transition depth of c. 50 km, however, is difficult to explain through mineralogical or thermal weakening mechanisms. Rather, I propose that mechanical removal of rheologically weak and buoyant rocks along the subduction interface leads to seismic decoupling and dynamic coupling bet! ween slab and mantle to drive mantle wedge convection and arc volcanism.

UMD: Le Mével on volcanic unrest at large silicic systems

2017 University of Maryland Geology Colloquium Series

Friday, November 10th 2017 at 3:00 pm
in PLS 1130, UMD- College Park

Hélène Le Mével
DTM/Carnegie Institution for Science

Geodetic measurements and numerical models of volcanic unrest at large silicic systems.

I will examine the ground deformation associated to non-eruptive unrests at two volcanic systems: the Laguna del Maule volcanic field (Chile), experiencing high uplift rates since 2007, and the Long Valley caldera (USA), experiencing multiple episodes of surface uplift over the last 40 years. I will present results from analytical and numerical models to interpret these episodes of ground deformation in terms of magmatic processes.

UMD: Georgetown’s Johnson on “Life on Mars” (+ distant moons)

2017 Geology Colloquium Series at the University of Maryland, College Park
Friday, November 3rd 2017 at 3:00 pm
in PLS 1130
Sarah Johnson
Georgetown University
Searching for Life on Mars and Distant Moons
Advances in molecular biology have the potential to alter the way we look for life in solar system, from direct detections to a deeper understanding of how biology affects patterns of mineralization. This talk will discuss our ongoing research into biosignature detection, including work in planetary analog environments like Australian acid salt lakes and the Dry Valleys of Antarctica. It will explore how handheld sequencers are starting to change the way we do remote field work, and how one day they may transform biological observation of the most inaccessible places on Earth, just as remotely telemetered image data revolutionized our understanding of the planet at the dawn of the Space Age. The talk will conclude with possibilities for nanopore-based life detection, including a concept that harnesses the power of sequencing to fingerprint patterns of surface chemical complexity as signatures of life, regardless of whether that life is based on nucleic acids.