Current Conference:
Eclogites in Space and Time – Bridging the Micro to Planetary Scales
Rohnert Park, California, USA | 19–23 June 2025
Know Before
You Go
Program and
Abstract Volume
Field Guide
(Non-Peer Reviewed)
International Eclogite Conference
Eclogites in Space and Time — Bridging the Micro to Planetary Scales
will represent the 15th meeting of the International Eclogite Conference
(IEC-15). The IEC was established in 1982 to promote worldwide
communication and cooperation among scientists who study high-pressure
and ultrahigh-pressure rocks and processes.
Find out more about the IEC
Description
The multidisciplinary study of eclogites from micro to planetary scales over the past 50 years has
significantly advanced our understanding of plate tectonics. Eclogites are both the recorders and drivers of
planetary-scale tectonics, and their formation is involved in such diverse processes as the geochemical exchange
between Earth’s surface and deep interior, intermediate-depth seismicity, and continental growth, collision, and
evolution.
Objectives
The objective of this Penrose Conference is to bring together the international eclogite community and
scientists working on subduction-zone processes to discuss recent advances in diverse fields (e.g., geodynamics,
geochemistry, experimental petrology, and geochronology); catalyze breakthroughs in our understanding of
subduction-zone processes; and chart future research on eclogites in space and time.
This Penrose Conference will represent the 15th International Eclogite Conference (IEC15) and will be the first
time U.S.-based scientists host the international eclogite community at a dedicated conference.
Conference Format
The conference format will include oral presentations, poster presentations, breakout discussions, and
mentoring opportunities for early career scientists. Attendees will be expected to observe the GSA Code of
Ethics & Professional Conduct throughout the meeting.
The venue is close to some of the classic localities of the Franciscan Complex, which we will visit during two
syn-conference field excursions. Learn more about the venue online.
Thematic Sessions
Eclogites, Micro to Macro Scales
What processes do eclogites and eclogite-facies rock reveal at different scales? How do new insights from
micro-scale observations on high-pressure and ultrahigh-pressure (HP–UHP) metamorphic rocks better constrain and
inform subduction-zone processes? This thematic session will explore the state of knowledge regarding bridging
the scales in eclogite research.
Advances in Methods: Thermobarometry and Geo/ Thermochronology
Mineral assemblages preserved in HP–UHP metamorphic rocks challenge the assumption that equilibrium was
attained during prograde, peak, and retrograde conditions. This thematic session will explore advances in
thermo-barometry and geo/thermochronologic techniques used to determine the
pressure-temperature-time-deformation (P-T-t-D) histories of eclogite and related rocks.
The Role of Eclogite in Geodynamics
This thematic session will explore how P-T-t paths and deformation histories of eclogites (and related
rocks) can be used to improve our understanding of paleogeothermal gradients, and thus the thermal evolution of
our planet. It will include how seismic tomography can be integrated with observations from exhumed rocks to
constrain the role of eclogites in Earth’s geodynamic evolution.
The Franciscan and HP–UHP Rocks of the Circum-Pacific Realm
The Franciscan Complex of California is among the first natural laboratories for the study of subduction zones
and subduction processes. This session will focus on how the Franciscan Complex and other HP–UHP terranes in the
circum-Pacific realm formed and survived exhumation
to Earth’s surface. This thematic session will also explore how HP–UHP exhumation mechanisms differ between
long-lived and transient subduction zones.
Rheology of the Subduction Interface: Deformation and Earthquake Processes
Can exhumed analogs in the subduction-related metamorphic rock record be used to constrain the rheology of the
slab–mantle interface? How does the process of serpentinization affect fore-arc deformation and fluid transport
in the mantle wedge? This thematic session will explore the rheology of the subduction interface as preserved in
both the seismicity of active subduction zones and the geologic evolution of exhumed HP-UHP terranes.
Fluids, Melts, and Geochemical (Re)cycling in Subduction Zones
What are the roles of fluids and melts in the geochemical cycling in subduction zones? This thematic session
will explore how observations on HP–UHP metamorphic rocks can constrain the sources, pressures, and volumes of
fluids in subduction zones.
Sponsors