Depositional environment of oil shale within the Eocene Jijuntun Formation in the Fushun Basin (NE China)

Strobl, Susanne; Sachsenhofer, Reinhard F.; Bechtel, Achim; Gratzer, Reinhard; Groß, Doris; Bokhari, Syed Nadeem Hussain; Liu, Rong; Liu, Zhaojun; Meng, Qingtao; Sun, Pingchang

doi:10.1016/j.marpetgeo.2014.04.011

Cited by 56 publications

(50 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Oil yields ranging from 3.6 to 7.1 wt% classify these intervals as low-medium quality oil shales following Liu et al (2009). Compared with oil shales from Eocene fault-related coal-bearing basins in NE China such as the Fushun and Huadian Basins (Strobl et al, 2014(Strobl et al, , 2015, the relatively low quality of the Tuanyushan oil shales may be related to the lower organic productivity as reflected by the lower TOC contents.…”

Section: Hydrocarbon Potentialmentioning

confidence: 99%

Hydrocarbon Potential and Palaeo‐depositional Environment of Lacustrine Source Rocks: Middle Jurassic Shimengou Formation, Northern Qaidam Basin, Nw China

Meng

Bechtel

Sachsenhofer

et al. 2018

Journal of Petroleum Geology

View full text Add to dashboard Cite

The Middle Jurassic Shimengou Formation in the Qaidam Basin, NW China, includes coals and lacustrine source rocks which locally reach oil shale quality (i.e. yielding >3.5 % oil on low‐temperature distillation). In the present study, the palaeo‐depositional environment and hydrocarbon potential of the 84.5 m thick Shale Member of the Shimengou Formation are investigated based on bulk geochemical parameters, organic petrographic data, biomarker analysis, and stable isotope geochemistry of 88 core samples. The Shale Member was deposited in an anoxic freshwater lake which formed following the drowning of a precursor low‐lying mire. Variations in bulk geochemical parameters allow four informal units to be identified, referred to (from the base up) as Units 1 to 4. These contain intervals of oil shale of varying thicknesses. In Unit 1, mudstones in the interval referred to as oil shale Layer 1 (true thickness [TD]: 2.06 m) are OM‐rich as a result of algal blooms and photic zone anoxia, and correspond to an initial flooding event. Subsequently, productivity of aquatic organisms decreased, resulting in the deposition of organic‐lean mudstones in Unit 2. Oil shale Layers 2 (TD: 2.03 m) and 3 (TD: 8.03 m) near the base of Unit 3 were deposited during maximum water depths. As with Layer 1, high productivity by algal blooms resulted in photic zone anoxia in a stratified water column. The shales in the upper part of Unit 3 are characterized by high TOC contents and a gradual increased input of terrigenous OM, and were deposited in a stable semi‐deep lake. Finally, organic‐lean mudstones in Unit 4 were deposited in shallow lacustrine conditions. The reconstruction of depositional environments in thick, non‐marine shale‐rich successions by mineralogical, petrographic and inorganic geochemical methods may be challenging as a result of the homogenous composition of component mudstones. The results of this study indicate, however, that sub‐division and basin‐wide correlation of such intervals can be achieved by organic geochemical analyses. Oil shales and organic‐rich mudstones in Units 1 and 3 of the Shimengou Formation Shale Member are excellent oil‐prone source‐rocks with a Source Potential Index of 3.2 t HC/m2. Considering the large area covered by the Shimengou Formation in the northern Qaidam Basin (∼34,000 km2), the results of this study highlight the regional significance for future petroleum exploration. They indicate that variations in organic productivity and dilution by minerals are key factors controlling the abundance and type of organic matter in the formation. An understanding of these factors will assist with the identification of exploration targets.

show abstract

Section: Hydrocarbon Potentialmentioning

confidence: 99%

Hydrocarbon Potential and Palaeo‐depositional Environment of Lacustrine Source Rocks: Middle Jurassic Shimengou Formation, Northern Qaidam Basin, Nw China

Meng

Bechtel

Sachsenhofer

et al. 2018

Journal of Petroleum Geology

View full text Add to dashboard Cite

show abstract

“…The oil shale-bearing succession was deposited in a rapidly subsiding freshwater lake. Low quality oil shale (oil yield b 4.7 wt.%) was deposited in the lower part (shallow lake), whereas oil shale with high quality (oil yield N4.7 wt.%) was deposited in the upper part (deep lake; Liu et al, 2009;Strobl et al, 2014).…”

Section: Geological Settingmentioning

confidence: 99%

“…Huang et al (1983) reconstructed a moist subtropical climate for the time of coal accumulation within the Guchengzi Formation. Modified according to Hong et al (1980), Wu et al (2000), Meng et al (2012), andStrobl et al (2014).…”

Section: Geological Settingmentioning

confidence: 99%

“…Models were calibrated by modifying heat flow and the thickness of eroded sediments until a satisfactory fit between measured and calculated values was obtained. Vitrinite reflectance and hopane isomerization data from the overlying Jijuntun Formation were adopted from Strobl et al (2014). Input parameters include stratigraphic information about the sediments within the Fushun Basin.…”

Section: ¼ A=bmentioning

confidence: 99%

“…Peat accumulation was ceased by rapid subsidence, resulting in a lacustrine environment in which organic-rich shales were deposited. Significant amounts of land-plant material were transported into the shallow lake after termination of peat accumulation (Strobl et al, 2014).…”

Section: Stage 3 (Transition Zone Between Mire and Lake)mentioning

confidence: 99%

See 2 more Smart Citations

Paleoenvironment of the Eocene coal seam in the Fushun Basin (NE China): Implications from petrography and organic geochemistry

Strobl

Sachsenhofer

Bechtel

et al. 2014

International Journal of Coal Geology

Self Cite

View full text Add to dashboard Cite

Paleoweathering and paleoenvironmental change recorded in lacustrine sediments of the early to middle Eocene in Fushun Basin, Northeast China

Chen

Ding

Tang

et al. 2017

Geochem Geophys Geosyst

View full text Add to dashboard Cite

Deciphering the long-term interaction among continental silicate weathering, global climate, and atmospheric CO 2 concentrations is helpful in understanding the mechanisms of the Cenozoic climate change and accessing the future climatic and environmental response to anthropogenic carbon emissions. The Eocene, which is characterized by the Early Eocene Climatic Optimum (EECO) and the following global cooling, represents an ideal test case. Here we generate geochemical data of the Eocene lacustrine sediments from the Fushun Basin, northeast China, to explore the regional climatic response to the global climate change. The chemical index of alteration (CIA) and plagioclase index of alteration (PIA) consistently show a gradual, long-term decrease, indicating a climatic transition from warm and humid to relatively cold and arid during the Eocene in the Fushun Basin. This climatic trend is broadly coincident with the global cooling and decreasing CO 2 concentration, implying that the regional climate is closely correlated with the global climate change over geological time scales. Additionally, the extreme silicate weathering and high lake productivity as reflected by relatively positive d 13 C values of lacustrine organic matter are associated with the EECO. This consistency may demonstrate that enhanced continental weathering and lake productivity had served as effective sinks to lower atmospheric CO 2 across the EECO. Collectively, our new geochemical data add supporting evidence for a long-term, close coupling among continental silicate weathering, climate, and global carbon cycle during the Eocene.

show abstract

Depositional environment of oil shale within the Eocene Jijuntun Formation in the Fushun Basin (NE China)

Cited by 56 publications

References 53 publications

Hydrocarbon Potential and Palaeo‐depositional Environment of Lacustrine Source Rocks: Middle Jurassic Shimengou Formation, Northern Qaidam Basin, Nw China

Hydrocarbon Potential and Palaeo‐depositional Environment of Lacustrine Source Rocks: Middle Jurassic Shimengou Formation, Northern Qaidam Basin, Nw China

Paleoenvironment of the Eocene coal seam in the Fushun Basin (NE China): Implications from petrography and organic geochemistry

Paleoweathering and paleoenvironmental change recorded in lacustrine sediments of the early to middle Eocene in Fushun Basin, Northeast China

Contact Info

Product

Resources

About