Magnetostratigraphy of sediments from Lake El'gygytgyn ICDP Site 5011-1: paleomagnetic age constraints for the longest paleoclimate record from the continental Arctic

Abstract. Paleomagnetic measurements were performed on sediments drilled from ICDP Site 5011-1 in Lake El'gygytgyn (67°30' N, 172°05' E) located in Far East Russian Arctic. The lake fills partly a crater formed by a meteorite impact 3.58 ± 0.04 Ma ago. Sediments from three parallel cores (5011-1A, 5011-1B and 5011-1C), recovered from the middle part of the lake, yielded a total of 355 m of sediment. Sediments are characterized by variable lithology, where intervals of homogenous and laminated sediments alternate, and mass movement deposits of variable thickness occur frequently along the sediment profile. Mineral magnetic investigation made on sediments enclosed in core catchers suggests that magnetic carrier in these sediments is partly maghemitized Ti-rich pseudo-single domain magnetite. Its detrital origin could be shown by mineral magnetic measurements and SEM-EDS analyses performed on mini-sized cylindrical rock samples, polished rock sections, creek sediments and magnetic extracts prepared from them. The intensity of the natural remanent magnetization (NRM) in the sediments is mainly high with a range from about 1 to 1000 mA m−1. Most of the sediments carry a stable magnetization component interpreted as primary depositional remanent magnetization. Characteristic inclination data show alternating intervals of steep positive and negative inclinations that were used to assign magnetic polarity to the lake sediment profile. This was a rather straightforward procedure owing to the mainly high quality of data. The Matuyama/Gauss (2.608 Ma) and Brunhes/Matuyama (0.780 Ma) reversals were recognized in the sediments. Furthermore, during the Gauss chron the Mammoth and Kaena reversed subchrons, and during the Matuyama, the Olduvai and Jaramillo normal subchrons, as well as the Réunion and Cobb Mountain cryptochrons were identified. Sediment deposition rate is highest at the base of the sequence laid down in the beginning of Gauss chron, when deposition rate is approximately 44 cm kyr−1. Sediment deposition decelerates upcore and it is an order of magnitude lower during the Brunhes chron when compared to that in early the Gauss chron. Decrease in sediment deposition in late Pliocene probably relates to atmospheric and oceanic reorganization heralding the onset of Quaternary climate change. The high-quality magnetostratigraphy reconstructed from Lake El'gygytgyn sediments provides 12 tie-points to pin down the age of the longest paleoclimate record from the continental Arctic.

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Magnetostratigraphy of sediments from Lake El'gygytgyn ICDP Site 5011-1: paleomagnetic age constraints for the longest paleoclimate record from the continental Arctic

Climate of the Past ◽

10.5194/cp-10-623-2014 ◽

2014 ◽

Vol 10 (2) ◽

pp. 623-642 ◽

Cited By ~ 9

Author(s):

E. M. Haltia ◽

N. R. Nowaczyk

Keyword(s):

Deposition Rate ◽

Remanent Magnetization ◽

Far East ◽

Sediment Deposition ◽

Laminated Sediments ◽

High Quality ◽

Sediment Profile ◽

Quaternary Climate ◽

Lake El’Gygytgyn ◽

Mineral Magnetic

Abstract. Paleomagnetic measurements were performed on sediments drilled from ICDP Site 5011-1 in Lake El'gygytgyn (67°30' N, 172°05' E) located in Far East Russian Arctic. The lake partly fills a crater formed by a meteorite impact 3.58 ± 0.04 Ma ago. Sediments from three parallel cores (5011-1A, 5011-1B and 5011-1C), recovered from the middle part of the lake, yield a total of 355 m of sediment. Sediments are characterized by a variable lithology, where intervals of homogenous and laminated sediments alternate, and mass movement deposits occur frequently along the sediment profile. Mineral magnetic investigation made on sediments enclosed in core catchers suggests that magnetic carrier in these sediments is partly maghemitized Ti-rich pseudo-single domain magnetite. Its detrital origin can be shown by mineral magnetic measurements and SEM-EDS analyses performed on mini-sized cylindrical rock samples, polished rock sections and creek sediments. The intensity of the natural remanent magnetization in the sediments is high with a range from about 1 to 1000 mA m−1. Most of the sediments carry a stable magnetization interpreted as primary depositional remanent magnetization. Characteristic inclination data show alternating intervals of steep positive and negative inclinations that are used to assign magnetic polarity to the lake sediment profile. This is a rather straightforward procedure owing to the mainly high quality of data. The Matuyama/Gauss (M/G) (2.608 Ma) and Brunhes/Matuyama (B/M) (0.780 Ma) reversals were recognized in the sediments. The Mammoth and Kaena reversed subchrons were identified during the Gauss chron, and the Olduvai and Jaramillo normal subchrons as well as the Réunion and Cobb Mountain cryptochrons were identified during the Matuyama chron. Sediments also provide a record of the Olduvai precursor and Intra-Jaramillo geomagnetic excursions. Sediment deposition rate is highest at the base of the sequence laid down in the early Gauss chron, when the deposition rate is approximately 44 cm kyr−1. Sediment deposition decelerates upcore and it is an order of magnitude lower during the Brunhes chron in comparison with the early Gauss chron. Decrease in sediment deposition in the late Pliocene probably relates to atmospheric and oceanic reorganization heralding the onset of Quaternary climate change. The high-quality magnetostratigraphy reconstructed from Lake El'gygytgyn sediments provides 12 first-order tie points to pin down the age of the longest paleoclimate record from the continental Arctic.

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Preparation of High-Quality Undoped Microcrystalline Silicon with High Deposition Rate Using Mercury-Sensitized Photochemical Vapor Deposition Method

Japanese Journal of Applied Physics ◽

10.1143/jjap.35.5625 ◽

1996 ◽

Vol 35 (Part 1, No. 11) ◽

pp. 5625-5630 ◽

Cited By ~ 8

Author(s):

Jae Hoon Jang ◽

Koeng Su Lim

Keyword(s):

Deposition Rate ◽

Vapor Deposition ◽

High Deposition Rate ◽

Deposition Method ◽

Microcrystalline Silicon ◽

High Quality ◽

Photochemical Vapor Deposition

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Hetero-Epitaxial Growth of 3C-SiC on Silicon Substrates by Plasma Assisted CVD

Materials Science Forum ◽

10.4028/www.scientific.net/msf.527-529.299 ◽

2006 ◽

Vol 527-529 ◽

pp. 299-302

Author(s):

Hideki Shimizu ◽

Yosuke Aoyama

Keyword(s):

Substrate Temperature ◽

Single Crystal ◽

Epitaxial Growth ◽

Deposition Rate ◽

Crystalline Structure ◽

Flow Rate ◽

Silicon Substrates ◽

High Quality ◽

Sic Films ◽

Lower Substrate Temperature

3C-SiC films grown on carbonized Si (100) by plasma-assisted CVD have been investigated with systematic changes in flow rate of monosilane (SiH4) and propane (C3H8) as source gases. The deposition rate of the films increased monotonously and the microstructures of the films changed from 3C-SiC single crystal to 3C-SiC polycrystal with increasing flow rate of SiH4. Increasing C3H8 keeps single crystalline structure but results in contamination of α-W2C, which is a serious problem for the epitaxial growth. To obtain high quality 3C-SiC films, the effects of C3H8 on the microstructures of the films have been investigated by reducing the concentration of C3H8. Good quality 3C-SiC single crystal on Si (100) is grown at low net flow rate of C3H8 and SiH4, while 3C-SiC single crystal on Si (111) is grown at low net flow rate of C3H8 and high net flow rate of SiH4. It is expected that 3C-SiC epitaxial growth on Si (111) will take placed at a higher deposition rate and lower substrate temperature than that on Si (100).

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Vegetation responses to interglacial warming in the Arctic: examples from Lake El'gygytgyn, Far East Russian Arctic

Climate of the Past ◽

10.5194/cp-9-1211-2013 ◽

2013 ◽

Vol 9 (3) ◽

pp. 1211-1219 ◽

Cited By ~ 21

Author(s):

A. V. Lozhkin ◽

P. M. Anderson

Keyword(s):

Deciduous Forest ◽

Russian Far East ◽

Coniferous Forest ◽

Far East ◽

The Arctic ◽

Dark Coniferous Forest ◽

Vegetation Responses ◽

Wide Range ◽

Lake El’Gygytgyn ◽

Shrub Tundra

Abstract. Preliminary analyses of Lake El'gygytgyn sediment indicate a wide range of ecosystem responses to warmer than present climates. While palynological work describing all interglacial vegetation is ongoing, sufficient data exist to compare recent warm events (the postglacial thermal maximum, PGTM, and marine isotope stage, MIS5) with "super" interglaciations (MIS11, MIS31). Palynological assemblages associated with these climatic optima suggest two types of vegetation responses: one dominated by deciduous taxa (PGTM, MIS5) and the second by evergreen conifers (MIS11, MIS31). MIS11 forests show a similarity to modern Picea–Larix–Betula–Alnus forests of Siberia. While dark coniferous forest also characterizes MIS31, the pollen taxa show an affinity to the boreal forest of the lower Amur valley (southern Russian Far East). Despite vegetation differences during these thermal maxima, all glacial–interglacial transitions are alike, being dominated by deciduous woody taxa. Initially Betula shrub tundra established and was replaced by tundra with tree-sized shrubs (PGTM), Betula woodland (MIS5), or Betula–Larix (MIS11, MIS31) forest. The consistent occurrence of deciduous forest and/or high shrub tundra before the incidence of maximum warmth underscores the importance of this biome for modeling efforts. The El'gygytgyn data also suggest a possible elimination or massive reduction of Arctic plant communities under extreme warm-earth scenarios.

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Chronology of Lake El'gygytgyn sediments – a combined magnetostratigraphic, palaeoclimatic and orbital tuning study based on multi-parameter analyses

Climate of the Past ◽

10.5194/cp-9-2413-2013 ◽

2013 ◽

Vol 9 (6) ◽

pp. 2413-2432 ◽

Cited By ~ 44

Author(s):

N. R. Nowaczyk ◽

E. M. Haltia ◽

D. Ulbricht ◽

V. Wennrich ◽

M. A. Sauerbrey ◽

...

Keyword(s):

Global Climate ◽

Far East ◽

Climatic Conditions ◽

Sedimentation Rates ◽

Scientific Drilling ◽

Lake El’Gygytgyn ◽

Age Model ◽

Orbital Tuning ◽

Lake Floor ◽

The Impact

Abstract. A 318-metre-long sedimentary profile drilled by the International Continental Scientific Drilling Program (ICDP) at Site 5011-1 in Lake El'gygytgyn, Far East Russian Arctic, has been analysed for its sedimentologic response to global climate modes by chronostratigraphic methods. The 12 km wide lake is sited off-centre in an 18 km large crater that was created by the impact of a meteorite 3.58 Ma ago. Since then sediments have been continuously deposited. For establishing their chronology, major reversals of the earth's magnetic field provided initial tie points for the age model, confirming that the impact occurred in the earliest geomagnetic Gauss chron. Various stratigraphic parameters, reflecting redox conditions at the lake floor and climatic conditions in the catchment were tuned synchronously to Northern Hemisphere insolation variations and the marine oxygen isotope stack, respectively. Thus, a robust age model comprising more than 600 tie points could be defined. It could be shown that deposition of sediments in Lake El'gygytgyn occurred in concert with global climatic cycles. The upper ~160 m of sediments represent the past 3.3 Ma, equivalent to sedimentation rates of 4 to 5 cm ka−1, whereas the lower 160 m represent just the first 0.3 Ma after the impact, equivalent to sedimentation rates in the order of 45 cm ka−1. This study also provides orbitally tuned ages for a total of 8 tephras deposited in Lake El'gygytgyn.

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Petrophysical characterization of the lacustrine sediment succession drilled in Lake El'gygytgyn, Far East Russian Arctic

Climate of the Past Discussions ◽

10.5194/cpd-9-351-2013 ◽

2013 ◽

Vol 9 (1) ◽

pp. 351-391 ◽

Cited By ~ 4

Author(s):

A. C. Gebhardt ◽

A. Francke ◽

J. Kück ◽

M. Sauerbrey ◽

F. Niessen ◽

...

Keyword(s):

Mass Movement ◽

Far East ◽

Lacustrine Sediments ◽

Lacustrine Sediment ◽

Organic Carbon Content ◽

Meteorite Impact ◽

Seismic Profiles ◽

Scientific Drilling ◽

Lake El’Gygytgyn ◽

Lake Floor

Abstract. Seismic profiles of Far East Russian Lake El'gygytgyn which was formed by a meteorite impact some 3.6 million years ago show a stratified sediment succession that can be separated into Subunits Ia and Ib at approximately 167 m below lake floor (= ∼ 3.17 Ma). The former is well-stratified, while the latter is acoustically more massive. The sediments are intercalated with frequent mass movement deposits mainly in the proximal parts, while the distal part is almost free of such deposits at least in the upper part. In spring 2009, a long core drilled in the lake center within the framework of the International Continental Scientific Drilling Program (ICDP) penetrated the entire lacustrine sediment succession down to ~ 320 m below lake floor and about 200 m further into the meteorite-impact related bedrock. Downhole logging data down to 390 m below lake floor show that the bedrock and the lacustrine part of the core differ largely in their petrophysical characteristics. The contact between the bedrock and the lacustrine sediments is not abrupt, but rather transitional with a mixture of impact-altered bedrock clasts in a lacustrine matrix with varying percentages. Physical and chemical proxies measured on the cores can be used to divide the lacustrine part into five different clusters. These can be plotted in a redox-condition vs. input type diagram with total organic carbon content and magnetic susceptibility values indicating anoxic or oxic conditions and with the Si/Ti ratio representing more clastic or more biogenic input. Plotting the clusters in this diagram allows identifying clusters that represent glacial phases (Cluster I), super interglacials (Cluster II), and interglacial phases (Clusters III and IV).

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Low Temperature Deposited High Quality ITO Films Prepared by E-Beam Evaporation

MRS Proceedings ◽

10.1557/proc-187-147 ◽

1990 ◽

Vol 187 ◽

Author(s):

C. S. Chang ◽

J. C. Wang ◽

L. C. Kuo

Keyword(s):

Electron Beam ◽

Low Temperature ◽

Substrate Temperature ◽

Optimal Condition ◽

Deposition Rate ◽

Oxygen Pressure ◽

Electron Beam Evaporation ◽

Film Properties ◽

High Quality ◽

Ito Films

AbstractAn electron beam evaporation method has been used to prepare tin doped indium oxide (ITO) films with 95 wt.% In2O3 and 5 wt.% SnO2 in an oxygen atmosphere. It was found that the deposition rate and oxygen pressure strongly influence the film properties when the substrate temperature was lower than 200°C. In an optimal condition, highly transparent (transmittance ˜ 90% at wavelength 570 nm) and conductive (resistivity – 3×10−4Ω-cm) films of thickness around 2000 Å at substrate temperature as low as 180°C can be obtained.

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Multivariate statistic and time series analyses of grain-size data in quaternary sediments of Lake El'gygytgyn, NE Russia

Climate of the Past ◽

10.5194/cp-9-2459-2013 ◽

2013 ◽

Vol 9 (6) ◽

pp. 2459-2470 ◽

Cited By ~ 17

Author(s):

A. Francke ◽

V. Wennrich ◽

M. Sauerbrey ◽

O. Juschus ◽

M. Melles ◽

...

Keyword(s):

Time Series ◽

Grain Size ◽

Far East ◽

Principal Component ◽

Sediment Supply ◽

Multivariate Statistic ◽

Lake El’Gygytgyn ◽

Lake Center ◽

The Impact ◽

Size Data

Abstract. Lake El'gygytgyn, located in the Far East Russian Arctic, was formed by a meteorite impact about 3.58 Ma ago. In 2009, the International Continental Scientific Drilling Program (ICDP) at Lake El'gygytgyn obtained a continuous sediment sequence of the lacustrine deposits and the upper part of the impact breccia. Here, we present grain-size data of the past 2.6 Ma. General downcore grain-size variations yield coarser sediments during warm periods and finer ones during cold periods. According to principal component analysis (PCA), the climate-dependent variations in grain-size distributions mainly occur in the coarse silt and very fine silt fraction. During interglacial periods, accumulation of coarser material in the lake center is caused by redistribution of clastic material by a wind-induced current pattern during the ice-free period. Sediment supply to the lake is triggered by the thickness of the active layer in the catchment and the availability of water as a transport medium. During glacial periods, sedimentation at Lake El'gygytgyn is hampered by the occurrence of a perennial ice cover, with sedimentation being restricted to seasonal moats and vertical conduits through the ice. Thus, the summer temperature predominantly triggers transport of coarse material into the lake center. Time series analysis that was carried out to gain insight into the frequency of the grain-size data showed variations predominately on 98.5, 40.6, and 22.9 kyr oscillations, which correspond to Milankovitch's eccentricity, obliquity and precession bands. Variations in the relative power of these three oscillation bands during the Quaternary suggest that sedimentation processes at Lake El'gygytgyn are dominated by environmental variations caused by global glacial–interglacial variations (eccentricity, obliquity), and local insolation forcing and/or latitudinal teleconnections (precession), respectively.

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