GIST 환경에너지 공학과 지구물질과학연구실에 방문하신 것을 환영합니다!
현재 대학원생 및 학부인턴 모집 중입니다.
극한환경과학 및 지구물질을 이용한 환경유해물질저감 연구 또는 고체지구물질순환연구 에 관심 있는 학생들은 언제든지 아래의 메일로 연락 주시기 바랍니다.

Water is the most abundant volatile component in the Earth. It continuously enters the mantle through subduction zones, where it reduces the melting temperature of rocks to generate magmas. The dehydration process in subduction zones, which determines whether water is released from the slab or transported into the deeper mantle, is an essential component of the deep water cycle. Here we use in situ and time-resolved high-pressure/high-temperature synchrotron X-ray diffraction and infrared spectra to characterize the structural and chemical changes of the clay mineral kaolinite. At conditions corresponding to a depth of about 75	km in a cold subducting slab (2.7	GPa and 200	°C), and in the presence of water, we observe the pressure-induced insertion of water into kaolinite. This super-hydrated phase has a unit cell volume that is about 31% larger, a density that is about 8.4% lower than the original kaolinite and, with 29	wt% H
2
O, the highest water content of any known aluminosilicate mineral in the Earth. As pressure and temperature approach 19	GPa and about 800	°C, we observe the sequential breakdown of super-hydrated kaolinite. The formation and subsequent breakdown of super-hydrated kaolinite in cold slabs subducted below 200	km leads to the release of water that may affect seismicity and help fuel arc volcanism at the surface.

A role for subducted super-hydrated kaolinite in Earth's deep water cycle

High-pressure and high-temperature experiments using a resistively heated diamond anvil cell have the advantage of heating samples homogeneously with precise temperature control. Here, we present the design and performance of a graphite resistive heated diamond anvil cell (GRHDAC) setup for powder and single-crystal x-ray diffraction experiments developed at the Extreme Conditions Beamline (P02.2) at PETRA III, Hamburg, Germany. In the GRHDAC, temperatures up to 2000 K can be generated at high pressures by placing it in a water-cooled vacuum chamber. Temperature estimates from thermocouple measurements are within +/−35 K at the sample position up to 800 K and within +90 K between 800 and 1400 K when using a standard seat combination of cBN and WC. Isothermal compression at high temperatures can be achieved by employing a remote membrane control system. The advantage of the GRHDAC is demonstrated through the study of geophysical processes in the Earth’s crust and upper mantle region.

Graphite resistive heated diamond anvil cell for simutaneous high-pressure and high-temperature diffraction experiments

Iron is one of the most studied chemical elements due to its sociotechnological and planetary importance; hence, understanding its structural transition dynamics is of vital interest. By combining a short pulse optical laser and an ultrashort free electron laser pulse, we have observed the subnanosecond structural dynamics of iron from high-quality x-ray diffraction data measured at 50-ps intervals up to 2500 ps. We unequivocally identify a three-wave structure during the initial compression and a two-wave structure during the decaying shock, involving all of the known structural types of iron (α-, γ-, and ε-phase). In the final stage, negative lattice pressures are generated by the propagation of rarefaction waves, leading to the formation of expanded phases and the recovery of γ-phase. Our observations demonstrate the unique capability of measuring the atomistic evolution during the entire lattice compression and release processes at unprecedented time and strain rate.

Subnanosecond phase transition dynamics in laser-shocked iron

A role for subducted super-hydrated kaolinite in Earth’s deep water cycle

Novel experimental setup for megahertz X-ray diffraction in a diamond anvil cell at the High Energy Density (HED) instrument of the European X-ray Free-Electron Laser (EuXFEL)

Diamond precipitation dynamics from hydrocarbons at icy planet interior conditions

Synthesis of large and homogeneous single crystals of water-bearing minerals by slow cooling at deep-mantle pressures

X-ray free electron laser-induced synthesis of ε-iron nitride at high pressures

Super-hydration and reduction of manganese oxide minerals at shallow terrestrial depths

Effect of pressure treatment on the specific surface area in kaolin group minerals

Immobilization of large, aliovalent cations in the small-pore zeolite K-natrolite by means of pressure.

A MHz X-ray diffraction set-up for dynamic compression experiments in the diamond anvil cell

The stability of subducted glaucophane with the Earth’s secular cooling

X-ray free electron laser heating of water and gold at high static pressure

Phase transition kinetics of superionic H 2 O ice phases revealed by Megahertz X-ray free-electron laser-heating experiments

Shock compression experiments using the DiPOLE 100-X laser on the high energy density instrument at the European x-ray free electron laser: Quantitative structural analysis of …

Intense reactivity in sulfur–hydrogen mixtures at high pressure under x-ray irradiation

Pressure-induced hydration and formation of bilayer ice in nacrite, a kaolin-group clay

The structure of liquid carbon elucidated by in situ X-ray diffraction

A role for subducted albite in the water cycle and alkalinity of subduction fluids

Dynamic optical spectroscopy and pyrometry of static targets under optical and x-ray laser heating at the European XFEL

Graphite resistive heated diamond anvil cell for simultaneous high-pressure and high-temperature diffraction experiments

Earth Material Sciences Laboratory (EMSL)

교수님 소개

황희정

연구실 소개

연구실 키워드

알럼나이가 간 회사

연구실 지원 방법

대우 조건

연도별 논문 인용수

저널 & 학회 논문 출판 수

연구실 논문 목록

Graphite resistive heated diamond anvil cell for simutaneous high-pressure and high-temperature diffraction experiments

Subnanosecond phase transition dynamics in laser-shocked iron

A role for subducted super-hydrated kaolinite in Earth's deep water cycle

연구실 보유 특허

대학별 입시끈

우리 연구실 모집

교수님 소개

황희정

연구실 키워드

알럼나이가 간 회사

연구실 지원 방법

대우 조건

연도별 논문 인용수

저널 & 학회 논문 출판 수

연구실 논문 목록

Graphite resistive heated diamond anvil cell for simutaneous high-pressure and high-temperature diffraction experiments

Subnanosecond phase transition dynamics in laser-shocked iron

A role for subducted super-hydrated kaolinite in Earth's deep water cycle

연구실 보유 특허

최근 3년간 연구실적 높은 연구실

대학별 입시끈

우리 연구실 모집