UMD Geology: Zhang on Fe-Ni-S-C Liquid in the Earth’s Mantle

2017 University of Maryland Geology Colloquium Series

Friday, April 7th 2017 at 3:00 pm
in PLS 1140 (College Park campus)

Johnny Zhang
Scripps Institution of Oceanography

Fe-Ni-S-C Liquid in the Earth’s Mantle

Fe-Ni-S-C phases are accessory phases in the Earth’s mantle, but carry important geochemical and geophysical implications due to the contrasting physical and chemical properties between metallic and silicate phases. In the shallow mantle (<200 km), the metallic phase occurs as monosulfide solid solution (mss) or melt with near-monosulfide stoichiometries. To constrain the sulfide melt stability field and its Fe-Ni exchange with mantle silicate minerals, we performed experiments at comparable conditions (P, T, fO2) to Earth’s shallow mantle. In the deeper part of the upper mantle (200-410 km), the mantle become reduced, corresponding to an increase of metal activities in sulfide melt. To contain the composition of Fe-Ni-S melt and its storage of deep carbon, we performed experiments and thermodynamic calculations to show the evolution of Fe-Ni-S-C compositions and mantle silicates at deep upper mantle conditions. Based on the experim! ental and modeling exercise, further discussion will be made on the recent Fe-Ni-S-C liquid from deep diamonds (Smith et al. 2016). In the deepest part of Earth’ mantle (<2900 km), we propose that small quantities of Fe-Ni-S-C liquid is the cause for the two large low shear velocity provinces (LLSVPs). These Fe-Ni-S-C liquid is likely trapped during the crystallization of a dense basal magma ocean and therefore a potential carrier of primordial geochemical signature.

UMD: Viete on metamorphism as earthquake record

2017 Geology Colloquium Series

Friday, March 31st 2017 at 3:00 pm
in PLS 1140, University of Maryland, College Park

Daniel Viete
Johns Hopkins University

Metamorphism can record individual earthquake events in the subduction setting: evidence from the Franciscan Complex, California

Rhythmic major-element zoning has been documented in garnets from high pressure/low temperature (HP/LT) lenses within a number of worldwide subduction mélanges (e.g. California, Chinese Tianshan, Cuba, Greek Cyclades, Guatemala, Japan, Venezuela). These features reflect some fundamental process(es) in the subduction setting. In this talk, conditions of rhythmic zoning acquirement in HP/LT garnets of the Franciscan Complex, California are investigated by use of thermodynamic modeling of phase equilibria, and Raman and synchrotron Fourier transform infrared (FTIR) microspectroscopy.

Hornblende, omphacite and zoisite in the Franciscan rocks are also complexly zoned in major elements. Modeling of phase equilibria shows that modal contours for garnet, amphibole and zoisite are gently dipping in the P–T region that corresponds to the peak-metamorphic mineral assemblage. Metamorphic assemblage diagrams suggest that hydration/dehy! dration reactions involving garnet <—> zoisite (which also involve amphibole exchange or omphacite for glaucophane) are incredibly sensitive to changes in P (e.g. 5–10 vol.% absolute gain/loss of garnet for ΔP = 250 MPa). Major-element zoning in the Franciscan minerals may record repeated growth–partial dissolution cycles in response to P fluctuations in the subduction setting.

Quartz-in-garnet Raman barometry reveals varying P—on the order of 100–350 MPa, over radial distances of 10s of µm—in association with the major-element zoning in the Franciscan garnets. Results from synchrotron FTIR microspectroscopy demonstrate association between zone overgrowths and OH in garnet (a proxy for crystallization pressure in pyrope garnet). The microspectroscopy results confirm changes in P attended development of the rhythmic garnet zoning.

Steep compositional gradients defining the rhythmic major-element zo! ning limit time scales at peak T (and garnet growth–dissolution) conditions to < 1 Myr, requiring that individual growth–partial dissolution cycles were extremely brief. Overpressure on the order of 100s of MPa can develop by tectonic loading of the crust and is relieved with earthquake rupture. Seismic cycles represent ephemeral phenomena capable of accounting for development of rhythmic major-element zoning in HP/LT garnet, during subduction, as a result of fluctuations in P (and garnet stability). Metamorphic rocks may carry detailed records of the catastrophism that punctuates longer-term tectonometamorphic processes.

Technical Forum for Geohazards Impacting Transportation in Appalachia

Colleagues, Researchers, and Friends,

The 17th  Technical Forum for Geohazards Impacting Transportation in Appalachia is coming up, and we’d like you to consider sending in an abstract!  The deadline is June 12th, 2017.

Information on the conference can be found at http://www.marshall.edu/cegas/events/GITAR/default.aspx .

The Forum will be held in Blacksburg, Virginia, from August 15th to 17th, 2017, at Virginia Tech, hosted by the Virginia Department of Transportation.  Many of you know about the Forum, but if you don’t:  It’s a two-and-one-half day meeting focusing broadly on the intersection of geohazards and transportation, particularly in the Appalachian states.  It’s a great opportunity to present your recent geotechnical or geohazards research or new work, and for keeping connected with the industrial,  academic, and  public-sector geotechnical industries.

We also expect to have an excellent field trip this year, on Tuesday, August 15th, 2017.  The field trip will include a visit to the Virginia  Tech Transportation Institute Smart Road, which is a world-class facility for testing innovative transportation technology in a controlled environment.  The field trip will also include a demonstration of unmanned aerial vehicles for collecting geotechnical data, analysis of that data, and an update on the current Federal regulations on the use of such vehicles.

Over the years, the focus of the Forum has broadened to include themes of forensic geology, planning, emergency response, remote sensing, karst, seismics, and hydraulics, as well as many other related topics.  If it falls, floods, or fails, it’s something of interest to the Forum – the geographic focus does not need to be Appalachian.  This year’s technical sessions include:

  • UAV and Remote Sensing
  • Mine Hazards
  • Landslide Hazard Assessment and Characterization
  • Rock Reinforcement
  • Risk and Reliability
  • Rockfalls
  • Climate Change, Extreme Events Resiliency
  • GIS, Mapping, and Planning
  • Karst

The Forum has always been a high-value (and very economically reasonable) technical conference, filled with a roster of speakers presenting novel and innovative research, new industry standards and methods, insights into management and best practices, and lessons learned.  I anticipate that this year will be no different.

Please share this Call!  If this email has reached you in error, or you don’t want any further communications regarding the Forum, just notify me and I’ll remove you from the distribution list.

Thank you very much,

Brian Bruckno
540-480-5896

NOVA Science Seminar: Astrobiology

Friday, March 24, 2017

Ernst Center (CE Building), Forum

12:00 noon to 1:00 p.m.

Seemal Asghar, Maha Khalid, Luis Vallejo, and Nimra Viryam

Former NOVA Students who Studied under Dr. Muffarah Marr

Present:

“Astrobiology: The Origin, Evolution, Distribution, and Future of Life in the Universe”

11:30 a.m. to 11:55 a.m. – Meet and Greet and Light Refreshments in CE Forum

Presented by the Science Seminar Committee, of the Math, Science, and Engineering Division and the Annandale Campus Lyceum Committee

Abstract: Astrobiology is a cross-disciplinary subject involving understanding of biology, astronomy, geology, and chemistry. The underpinnings of the laws of physics as well as basic astronomy and planetary science lead the research toward an understanding of the origin, evolution and distribution of life in the Universe. A summary of the search for knowledge in astrobiology, annotated with findings from fossil searches, telescope examination, and interviews with iconic scientists, is presented.

Biography: The presenters are former NOVA students who were guided in their undergraduate research by Biology Adjunct Professor Dr. Muffarah Marr. They have each arranged to take time away from their current academic studies and professional commitments to present and share their undergraduate research experience with our NOVA academic community.

GSW 1518: seafloor, Titan, & granites

The 1518th meeting of the Geological Society of Washington will be on
Wednesday, March 29, 2017
,
featuring :

Jean-Arthur Olive, Lamont-Doherty Earth Observatory – Columbia University
“What’s shaping the seafloor?”

Carrie Anderson, NASA
“The Organic Inventory at Titan’s Poles Inferred from ~15 Years of Cassini Observations”

Mike Ackerman, Carnegie Institution for Science
“New Perspectives on an Age-old Question: How do Granites Form?”

AEG Environmental and Engineering Geology Symposium

Visit www.aeg-bwh.org for all of the information regarding the symposium and other AEG-DMV events.

Third Annual Environmental and Engineering Geology Symposium

April 7th and 8th, 2017 at James Madison University, Harrisonburg, Virginia

Convened by the DC-Maryland-Virginia (DMV) Chapter and the JMU Student Chapter of the Association of Environmental and Engineering Geologists (AEG)

The third annual AEG-DMV spring environmental and engineering geology symposium will be held on the campus of JMU in Memorial Hall. The spring symposium was established to provide a forum for the exchange of ideas, allow for students to meet potential employers, and to further the fellowship that exists between geoscientists.  Last year’s symposium was attended by over 50 geo-professionals, academics, and students from five universities. Lasting personal and professional relationships were forged. The Symposium will consist of the traditional poster and oral presentations on Saturday and a half-day field trip is planned on Friday to observe and learn about a cut slope failures on Interstate-64 crossing the Blue Ridge.

Friday, April 7, 2017

12:00 to 5:00 pm– Half-day field trip.  The field trip will involve visiting the nearby Blue Ridge Mountains near where Interstate-64 crosses the mountain where a slope failed in the past and where historical debris flows can be observed in the nearby vicinity.  In addition, a planned stop will also visit an old railroad tunnel that crosses the Blue Ridge and is under the cut slope.  The tunnel is now being converted into a bike trail.  Dr. Scott Eaton and Dr. Yonathan Admassu will discuss the cut slope features and tunnel.  Dr. Steven Whitmeyer, a structural geologist will guide the group to several stops to explain the geology of the Blue Ridge Mountains.  Please note the field trip is limited to the first 30 participants that sign up.

Saturday, April 8, 2017

08:00 to 08:30 – Symposium registration and continental breakfast

08:30 to 12:00 – Oral presentations – Memorial Hall, Room 6110

12:00 to 1:00 – Lunch & Poster presentations   Mineral Museum open for viewing

(Lunch provided by the AEG-DMV and JMU Student Chapter)

1:00 to 3:00 – Oral presentations – Memorial Hall, Room 6110

Symposium attendance is open to anyone with an interest in environmental and engineering geology.  Fees are based on your standing within AEG and as detailed below:

  • Student                        $30
  • Member                      $75
  • Non-member              $90
  • Field Trip                     $45

Since overnight travel is likely for some attendees, AEG-DMV has made arrangements with the following hotels:

Holiday Inn Express                            $91 per night (two Queen beds)

3325 South Main Street                      $129 per night (King bed)

Harrisonburg, Virginia

(540) 433-9999                                   4.1 miles south of Memorial Hall

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Hampton Inn                                       $134 per night (two Queen beds)

85 University Boulevard

Harrisonburg, Virginia                         2.8 miles east of Memorial Hall

(540) 432-1111

The Symposium will be held in Room 6110, Memorial Hall, located at 395 South High Street, Harrisonburg, VA 22801.  Parking is available near Memorial Hall, see attached map.

AEG-DMV and the JMU Student Chapter are excited to host this event and look forward to seeing you in Harrisonburg.  To register and pay via Paypal for the symposium, please log onto the AEG-DMV website (www.aeg-bwh.org).   Attendees can also pay by check at time of registration; however, please complete the event sign-up sheet at the bottom of this page, scan it, and return it to the AEG-DMV Spring Geology Symposium e-mail (AEGsymposium2017@yahoo.com) for head count purposes.

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General Directions to JMU Memorial Hall

From  I-81, get off at Exit 245 in Harrisonburg onto VA Rt. 253 / Port Republic Road – Maryland Avenue towards the west. After approximately 0.9 mile, turn right onto High Street.  Travel approximately 0.4 mile to the University parking lot on the left.

UMD Geology: Lewis (JHU) on Mars rover geology

2017 Geology Colloquium Series

Friday, February 24th 2017 at 3:00 pm
in PLS 1140

Kevin Lewis
Johns Hopkins University

Exploration of Gale Crater Mars with the Curiosity Mars Rover

The Curiosity Mars rover has been exploring its landing site at Gale crater since 2012. Over this time it has begun to climb the lower slopes of Mount Sharp, a 5 kilometer high mound of sedimentary rock located within the crater. In this talk, we will combine orbital and rover-based geological and geophysical tools to understand the formation of Mount Sharp, with potential implications for other crater-hosted mounds found commonly in the Martian equatorial region. The ultimate goal of this work, and one of the key objectives of the Curiosity mission, is to understand the climate information recorded in the strata of Mount sharp exposed along the rover traverse.