TY - JOUR

T1 - Mineralogy and geochemistry of fine-grained clastic rocks in the Eocene Huadian Basin (NE China): Implications for sediment provenance, paleoclimate and depositional environment

AU - Meng, Qingtao

AU - Sachsenhofer, Reinhard

AU - Liu, ZhaoJun

AU - Sun, PingChang

AU - Hu, Fei

AU - Zhou, RenJie

AU - Wang, KeBing

PY - 2017

Y1 - 2017

N2 - The Huadian Basin is a small fault-controlled basin in northeast China. It is filled by the Eocene Huadian Formation comprisingthick lacustrine oil shale-and coal-bearing sediments. Oil shale, mudstone and carbonaceous shale samples have been collectedto determine their mineralogical and geochemical (major, trace and rare earth elements) characteristics. These data are used toevaluate sediment provenance as well as paleoclimate and depositional environment. The fine-grained sediments in the HuadianFormation are derived from felsic volcanic rocks and granites, mixed with minor amounts of mafic and sedimentary rocks. Geochemical proxies confirm sediment recycling in the source region. Clay mineralogy and indices of chemical alteration suggest thata subtropical warm and humid climate prevailed during deposition of the fine-grained sediments. The data also suggest climaticchanges during deposition of the Huadian Formation, from a stable warm and humid climate causing intermediate chemical weathering (Pyrite Member), to a seasonal dry-wet climate (Oil Shale Member), to a stable warmer and more humid climate causingstrong chemical weathering (Carbonaceous Shale Member). Based on inorganic proxies, the fine-grained sediments in the Huadian Formation have been deposited in an anoxic fresh-water environment. Only the sediments of the Oil Shale Member reflectfluctuating freshwater and brackish conditions. The Eocene climatic change controlled lake level variations and water chemistry.A brackish and strictly anoxic environment together with a warm and humid climate was beneficial for the formation of highquality oil shale, whereas fresh-water conditions and warm and more humid climate favored peat accumulation.__

AB - The Huadian Basin is a small fault-controlled basin in northeast China. It is filled by the Eocene Huadian Formation comprisingthick lacustrine oil shale-and coal-bearing sediments. Oil shale, mudstone and carbonaceous shale samples have been collectedto determine their mineralogical and geochemical (major, trace and rare earth elements) characteristics. These data are used toevaluate sediment provenance as well as paleoclimate and depositional environment. The fine-grained sediments in the HuadianFormation are derived from felsic volcanic rocks and granites, mixed with minor amounts of mafic and sedimentary rocks. Geochemical proxies confirm sediment recycling in the source region. Clay mineralogy and indices of chemical alteration suggest thata subtropical warm and humid climate prevailed during deposition of the fine-grained sediments. The data also suggest climaticchanges during deposition of the Huadian Formation, from a stable warm and humid climate causing intermediate chemical weathering (Pyrite Member), to a seasonal dry-wet climate (Oil Shale Member), to a stable warmer and more humid climate causingstrong chemical weathering (Carbonaceous Shale Member). Based on inorganic proxies, the fine-grained sediments in the Huadian Formation have been deposited in an anoxic fresh-water environment. Only the sediments of the Oil Shale Member reflectfluctuating freshwater and brackish conditions. The Eocene climatic change controlled lake level variations and water chemistry.A brackish and strictly anoxic environment together with a warm and humid climate was beneficial for the formation of highquality oil shale, whereas fresh-water conditions and warm and more humid climate favored peat accumulation.__

KW - Fine-grained sediments

KW - Oil Shale

KW - Geochemistry

KW - Provenance

KW - Paleoclimate

KW - Environment

KW - Huadian Basin

M3 - Article

VL - 110.2017

JO - Austrian journal of earth sciences

JF - Austrian journal of earth sciences

SN - 2072-7151

IS - 2

ER -