Request Info
Dr. Close instructs undergraduate student Nicola Paul on operation of the GC-IRMS
Lipid extracts from a depth profile at Station ALOHA
Dr. Close deploying in situ pumps in the North Pacific
Dr. Close and Ph.D. student Shannon Doherty deploying in situ pumps in Monterey Bay
Lipid extracts from the Eastern Tropical North Pacific
R/V Knorr docked in Barbados on one of its last voyages in 2013 (Deep DOM cruise)
Sunset over the Eastern Tropical North Pacific
Installation of the magnet on the MAT 253 isotope ratio mass spectrometer
Group Photo, 2019-2020 Group Photo, 2019-2020
Close Lab group, 2019-2020
Close Lab group, 2017-2018

Marine Organic and Isotope Geochemistry

The Close Lab specializes in particle sampling, purification of organic compound classes, and compound-specific isotope analysis in order to constrain how organic matter is produced, degraded, and physically distributed in marine environments. The lab includes equipment for the extraction and purification of lipids, amino acids, and other compound classes and instrumentation for compound identification (GC-MS), bulk stable isotope analysis (EA-IRMS), and compound-specific isotope analysis of lipids and amino acids (GC-IRMS). Research opportunities for undergraduate students are frequently available.
We are currently searching for a lab analyst/manager. If you have experience and interest in continuous-flow IRMS, organic wet chem preparations, and general lab management please contact Dr. Close.

News and updates


February 2024:

  • New publication in PNAS! Lillian's work on carbon isotopic fractionation during photosynthesis has just been published, available here.
  • Liz, Lillian, Dailen, and Hilary had a great time at the 2024 Ocean Sciences Meeting in New Orleans, and we also bumped into lab alums Shannon, Josh, and Nicola! Liz presented AA-CSIA results from the North Atlantic EXPORTS campaign, Lillian presented stoichiometry and carbohydrate results from the BIOS-SCOPE project, and Dailen presented AA-CSIA results from his senior thesis work. Thank you to all of our colleagues who attended our presentations and provided valuable feedback.

Fall 2023:

  • Liz, Paul, and Hilary joined a research cruise on the R/V Sally Ride in October, led by collaborator Anela Choy. We collected a lot of size-fractionated particles from the upper 1000 m of the water column, which are on their way to some innovative analyses in our lab and those of several collaborators. Stay tuned! 
  • The 2023-2024 academic year is a busy one! We have four senior undergraduates conducting thesis work in our lab, we hosted a visitor from the Choy Lab to conduct AA-CSIA, and both Paul and Lillian are in the home stretch of their PhD research. Stay tuned for upcoming publications!

Summer 2023:

  • New open access publication! Paul's work on interpreting particle degradation mechanisms using nitrogen isotopes of amino acids is now available at Limnology and Oceanography.
  • Lillian and Hilary traveled to Spain to present at the 2023 ASLO Aquatic Sciences Meeting. Lillian presented recent results from the BIOS-SCOPE project, and Hilary presented an overview of CSIA advances in recent years. 
  • Paul will present his most recent work on the North Pacific EXPORTS project at the Goldschmidt meeting in Lyon on Friday, July 14th. Please stop by if you are here!
  • Liz will present her most recent results from the North Atlantic EXPORTS project at the Chemical Oceanography Gordon Research Conference. We look forward to seeing many current and new colleagues there!

Fall 2022:

  • We welcomed Rita García-Seoane as a visiting postdoctoral scholar for 3 months this fall. She conducted analysis of fatty acids and stable isotopes of several fish species from provinces around northern Spain. We look forward to continued collaboration with Rita!
  • Hilary enjoyed a trip to Germany for the Ocean Floor Symposium at MARUM, University of Bremen. Many thanks to her MARUM hosts and fellow attendees for an exciting meeting! She was able to add on some time to visit collaborators at GEOMAR and the Christian-Albrechts University of Kiel.
  • Paul, Lillian, Liz, and Hilary all continue to log ship time each semester on the R/V F.G. Walton Smith by participating in the FLOTSUM cruises (Florida Ocean Time Series by Undergraduates at UM), a series of 1-day cruises to the Florida Straits where Ocean Sciences faculty and graduate students give UM Marine Science undergraduates a taste of life, sample collection, and analyses at sea.

May 2022: 

  • Congratulations to recent graduate Chase Glatz (honors in Marine Science/Chemistry), who successfully completed his senior thesis in the lab. Chase independently adapted literature methods to extract lignin phenols from local plant materials and offshore marine DOM -- a challenging project with intriguing results. We will miss having Chase in the lab!
  • Paul Wojtal received an OCB travel grant to attend and present his EXPORTS results at the 2022 Gordon Research Conference in Ocean Biogeochemistry, which took place in Castelldefels, Spain. An exciting return to in-person conferences!
  • Over the summer we will be getting back into the lab, conducting our 5th cruise off Bermuda with the BIOS-SCOPE team, and attending the 2022 Organic Geochemistry Gordon Research Conference.
  • Hilary received notice of promotion to Associate Professor with tenure. She has also been named as a 2022 Sloan Research Fellow in Earth System Science. Big things ahead for the lab!

 February 2022:

 August 2021: 

  • We warmly welcome Elizabeth Yanuskiewicz, a first-year Ph.D. student who will be working on our North Atlantic EXPORTs project! For more on this project, click here.

 June 2021:

  • Shannon Doherty successfully defended her Ph.D. on June 14th -- congratulations Dr. Doherty!
  • Four students in the Close Lab will present research at the ASLO Aquatic Sciences virtual meeting. On June 24, look for a talk by Lillian Henderson on her recent work identifying photosynthetic carbon isotope signatures of the lower euphotic zone and a poster by Paul Wojtal on his work interpreting mechanisms of carbon flux attenuation in the northeast Pacific. On June 25, Shannon Doherty will give a talk on recent work using nitrogen isotopes of amino acids to estimate fecal pellet composition of particles in Monterey Bay, and Suzanne Stremler will present a poster demonstrating that the periostracum of deep-sea mussels retains unique compound-specific isotope signatures related to methanotrophy.

 May 2021:

 September 2020:

August 2020:

 Summer 2020:

  • This summer has been turbulent for many reasons. Lab members have continued to check in with each other frequently over video chats, have practiced safe interactions in the lab, and have been active in anti-racism efforts. Please visit the webpage of the Diversity, Equity and Inclusion Committee as one starting place for information about equipping ourselves to take active roles in building more inclusive and diverse STEM environments and for university plans for advancing racial justice.

 March 2020:

 February 2020:

 December 2019:

 August 2019:

  • We are excited to welcome two new Ph.D. students to the lab! Look out for great things from Lillian Henderson and Paul Wojtal.
  • Dr. Close presented at the 2019 Goldschmidt meeting in Barcelona. See the abstract here.

July 2019:

  • Dr. Close participated in her second summer research cruise with the BIOS-SCOPE collaboration, sampling large-volume, size-fractionated particles from the oligotrophic North Atlantic. Collaborators investigating microbial and metabolomic properties of these particle samples include Dr. Craig Carlson (UCSB) and Dr. Liz Kujawinski (WHOI).

June 2019:

  • This month we welcome summer undergraduate researcher Sophia Schiaroli from Franklin and Marshall College. She is joining MGS Ph.D. student Evan Moore in extracting organic biomarkers from shallow-water carbonate rocks.
  • At the same time, we bid a fond farewell to research assistant Nicola Paul, who has been the master of many lab techniques in her two years with our group. We wish her great success in her new position as Ph.D. student in the Santoro Lab at UCSB.

May 2019:

  • Shannon joined a research cruise to the BATS (oligotrophic North Atlantic) site with our EXPORTS collaborator Dr. Amy Maas (BIOS) to collect particles, zooplankton, and fecal pellets.

April 2019:

  • Via our partnership with the U.S. Geological Survey, we are excited to obtain samples from the water column and seafloor around a deep-sea coral habitat on the U.S. mid-Atlantic margin. See more about the multi-agency research happening this April on board the Ronald H. Brown here.

February 2019:

  • Dr. Close presented at the ASLO meeting in San Juan, Puerto Rico on our work with the U.S. Geological Survey at methane seeps in the mid-Atlantic.

September 2018:

  • The Close Lab has joined the EXPORTS team! We are grateful to our collaborators for collecting samples in the subarctic Pacific, onboard the R/V Roger Revelle and R/V Sally Ride in August-September, 2018. See our NSF project description here.

August 2018: