From macro-scale tectonics to molecular fossils and atomic isotopes

GRANTS

Zhuang has brought $1,145,250 of extramural fundings to LSU, leading a total budget of $1,829,105.

NSFGEO-NERC Award # 2217529 (09/01/2022 – 08/31/2025): Collaborative Research: NSFGEO-NERC: Solving the conundrum of the Miocene South Asian Monsoon: $652,927.00 (to LSU), total budget $1,336,782: Zhuang (lead PI)

NSF Award # 2022282 (08/01/2020 – 07/31/2023): Using organic biomarker paleohypsometry to reconstruct the punctuated uplift history of the Northern Tibetan Plateau: $284,603.00: Zhuang (Sole PI)

Contracts: $207,720

RESEARCH AREAS

  • Tectonics: Himalayas-Tibetan Plateau
  • Paleoclimate: Asian monsoons and Westerlies
  • Paleoceanography: upwelling in Western Arabian Sea
  • Paleoecology: C4-grassland expansion
  • Boundary events: Eocene-Oligocene Transition

My current research focuses on the biogeochemistry processes and the applications. I aim at understanding the production and preservation of organic molecules and the isotopic signatures in biomarkers and use this knowledge to study multi-sphere interactions.

2.topdown
Diagram emphasizing a top-down way to expand my vision and explore new research frontiers. R, O, and OH represent the alkyl, carbonyl, and hydroxyl functional groups, respectively; single (double) segments are saturated C-C (unsaturated C = C) bonds. Three arrow lines in the middle link the main categories of organic molecules (bold fonts within rectangle boxes) in sediments and sedimentary rocks with organisms in biosphere where they are synthesized via different pathways (acetogenic; mevalonate pathway – MVA; and methylerythritol phosphate or non-mevalonate pathway – MEP). The bottom arrow line highlights the inorganic substrates (CO2 and H2O) in the atmosphere and hydrosphere to sustain the biosynthesis processes in biosphere.

My research career began with a research project on the northern Tibetan Plateau that includes the intermountain Qaidam Basin, the foreland basin of Hexi Corridor, the Qilian Shan fold-thrust-belt, and the left-lateral strike-slip Altyn Tagh fault. To understand the growth history and the climatic impact of the northern Tibetan Plateau, I used an integrated approach (basin analysis, U-Th/He thermochronology, and carbonate stable oxygen and carbon isotopes).

Motivations_forMyWeb
Topographic map, showing the study locations and types of research in the northern Tibetan Plateau and the climatic regimes (arrows). Note: Major structures the Chinese Loess Plateau (brownish color) are denoted (barbed lines – thrust fault systems; pairs of arrows – strike-slip fault systems); AA’ denotes the topographic cross-section shown below.

My interests in biogeochemistry trace back to my first postdoctoral training at Yale. I have developed an approach that used the leaf wax n-alkane hydrogen isotopes and microbial tetraethers to constrain the paleo-elevation of orogenic belts and applied this approach to quantify the paleo-elevation of the Qaidam Basin and the paleo-relief between the Qilian Shan and the Qaidam Basin and Hexi Corridor (see details in my publications: Zhuang et al., 2014 EPSL and Zhuang et al., 2019 GRL).

Topographic cross-section through the Himalaya across the Tibetan Plateau with major geological features in the northern Tibetan Plateau being labeled (right). Note: Qaidam Basin – the largest intermountain basin on the plateau; Hexi Corridor – foreland basin.

We have used the sea surface temperature (SST) proxy based on isoprenoid GDGT to constrain the upwelling history in the western Arabian Sea by studying core samples at the Ocean Drilling Program (ODP) Sites 722B and 730A.

Himalaya-Tibetan Plateau with active faults (barbed lines, thrust; paired arrows, strike-slip) and surrounding regions. Green circles indicate ODP sites 730A and 722B with SST contours and winds in summer. Hexagons denote paleoaltimetry studies, supporting an Eocene proto-Plateau (red) and expansion of high topography in Neogene (yellow). Yellow triangles indicate themochronology studies, revealing rapid uplift in Pamir and Iranian Plateau in the Middle-Late Miocene. Yellow squares are faunal and sedimentary studies that support the restriction and disruption of Tethys Seaway in the Middle Miocene.

My group has used the leaf wax n-alkane hydrogen and carbon isotopes, biomarkers, along with the climatic modeling to understand the evolution of Asian summer monsoons and the interactions with the Westerlies on Myr- and Kyr-scales, and the Eocene-Oligocene Transition in Asia and North America (see Hou et al., 2020 GSA Bulletin; Wu et al., 2021 EPSL; Hou et al., 2022 GSA Bulletin for details).

30 year (1981-2010) record of winter (December-January-February) minus summer (June-July-August) precipitation (mm/day). Blue color represents greater precipitation in winter (December-January-February), while red color indicates greater precipitation in summer (June-July-August). Data are derived from NCEP Reanalysis provided by NOAA ESRL PSD at Colorado, Boulder, USA (https://www.esrl.noaa.gov/psd/data). The gray line outlines the 3000 m-contour on the Tibetan Plateau and surrounding mountain (adapted from Li et al., 2018). The Qaidam Basin (brown outline), core site (yellow star), and the Chinese Loess Plateau (CLP; dark blue outline) are noted. Arrows highlight the moisture transport via the Westerlies (green), Indian summer monsoon (blue), and East Asian summer monsoon (yellow). The black dashed line represents the modern boundary between the Asian summer monsoons (East Asian and Indian summer monsoons) and the Westerlies. Blue triangles are the location of isotope reconstruction of paleometeoric waters in the Hulu (H) (Wang et al., 2008), Dongge (G) (Dykoski et al., 2005), and Kesang (K) (Cheng et al., 2012) caves and the Dunde Ice core (D) (Thompson et al., 1989). Green circles denote the lakes and paleo-lakes discussed in the text: Lake Qinghai (QH) (Hou et al., 2016), Lake Sugan (S) (He et al., 2013Wang et al., 2013), Lake Keluke (H) (Rao et al., 2014), Tengger Desert (T), Qarhan (Q), Zabuye (Z), Aksayqin (A) (Yu et al., 2003) and Lisan (L) (Bartov et al., 2003). Black squares indicate the Global Network of Isotope in Precipitation (GNIP) meteorological stations (IAEA/WMO, 2006).