Cenozoic evolution of Asian climate and sources of Pacific seawater Pb and Nd derived from eolian dust of sediment core LL44‐GPC3

Pettke, Thomas; Halliday, Alex N.; Rea, David K.

doi:10.1029/2001pa000673

Cited by 99 publications

(115 citation statements)

References 61 publications

(141 reference statements)

Supporting

Mentioning

103

Contrasting

Unclassified

Order By: Relevance

“…A combined method of biostratigraphy and Co-model method [15,[23][24][25][26] is used for dating the crusts. Meanwhile, a method of comparison of Pb isotopes between these crusts and ODP sediment core LL44-GPC3 [27] is also used.…”

Section: Samples and Methodsmentioning

confidence: 99%

New index of ferromanganese crusts reflecting oceanic environmental oxidation

Zhou

Zhang

et al. 2007

SCI CHINA SER D

View full text Add to dashboard Cite

Ferromanganese crusts (hereinafter crusts) form in aerobic environment and the environmental oxidation degree is recorded by the redox sensitive element Co in the crusts. The ages of the layers from the surface to bottom of the crusts are determined, and main element contents at high resolution along the depth sections of three crusts from the Pacific Ocean are analyzed by an electron microprobe. Thus the variations of Co/(Fe+Mn) and Co/(Ni+Cu) with age/depth of the crust layers are obtained. By comparing the ratios of Co/(Fe+Mn) and Co/(Ni+Cu) with the δ 18 O curves of the Pacific benthic foraminifera, we find that these two ratios can reflect the variation of the environmental oxidation state under which the crust layers deposit. The evolution of the oxidation degree reflected by the two indexes resembles the evolution of temperature since the Oligocene reflected by the δ 18 O curves of the Pacific benthic foraminifera. This suggests that the crust-forming environment after the Oligocene is controlled mainly by the oxygen-rich bottom water originated from the Antarctic bottom water (AABW). However it is not the case prior to the Oligocene. Furthermore it suggests that the environmental oxidation degree controls the formation of the crusts and the Co contents in the crusts. This explains why the Co contents in the crusts increase with time up to now. ferromanganese crusts, the Pacific Ocean, oxidation degree of environment, the Oligocene, AABW Ferromanganese crusts are a kind of laminar authigenetic mineral deposit mainly composed of iron and manganese oxide from the seawater. Crusts formed mainly on naked bedrocks which locates on the top or slope of seamounts or submarine plateaus [1][2][3][4] . Recently research on palaeoceanography and palaeoenvironment using ferromanganese crusts has been a hot subject [5] , as crusts have some favourable characteristics for such research. Firstly, laminar crusts with rhythmicity have recorded the palaeoceanographic information for a few tens of million years, and they can serve as a "microfossil". Moreover, Crusts can record the history of periods during which no other sediments deposited in because they could form during such period. Secondly, they can reflect well the seawater compositions from which they formed because they are autogenetic sediments. Thirdly, crusts are enriched in many kinds of trace elements and radioactive elements, thus the study using these tracers can be easily conducted. The fourth, crusts were hardly disturbed by the deep-sea creatures or changed by other deep-sea processes. Palaeoceangraphic events could have important influences on the formation of crusts [6][7][8][9][10][11][12][13][14][15][16][17][18] , but the authors supposed that conditions of the palaeoceanography and palaeoenvironment studied

show abstract

Section: Samples and Methodsmentioning

confidence: 99%

New index of ferromanganese crusts reflecting oceanic environmental oxidation

Zhou

Zhang

et al. 2007

SCI CHINA SER D

View full text Add to dashboard Cite

show abstract

“…In this regard, it is worth noting that the onset of loess deposition at Qin'an in the Chinese Loess Plateau (20, 21) (see Fig. 1B for location), and change in the dust to the distal north Pacific Ocean (22)(23)(24) as shown by a significant increase in the detrital contribution and quartz content, occurred at about the same time (Fig. 3).…”

Section: U-pb Dating Of Zircon From Volcanic Ashmentioning

confidence: 99%

Late Oligocene–early Miocene birth of the Taklimakan Desert

Zheng

Xing

Tada

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

180

196

View full text Add to dashboard Cite

As the world’s second largest sand sea and one of the most important dust sources to the global aerosol system, the formation of the Taklimakan Desert marks a major environmental event in central Asia during the Cenozoic. Determining when and how the desert formed holds the key to better understanding the tectonic–climatic linkage in this critical region. However, the age of the Taklimakan remains controversial, with the dominant view being from ∼3.4 Ma to ∼7 Ma based on magnetostratigraphy of sedimentary sequences within and along the margins of the desert. In this study, we applied radioisotopic methods to precisely date a volcanic tuff preserved in the stratigraphy. We constrained the initial desertification to be late Oligocene to early Miocene, between ∼26.7 Ma and 22.6 Ma. We suggest that the Taklimakan Desert was formed as a response to a combination of widespread regional aridification and increased erosion in the surrounding mountain fronts, both of which are closely linked to the tectonic uplift of the Tibetan–Pamir Plateau and Tian Shan, which had reached a climatically sensitive threshold at this time.

show abstract

“…Nd isotopic composition of modern detrital silicate samples in the central North Pacific is shown to be comparable to those of Chinese Loess Plateau (CLP) (John et al, 2001;Jones et al, 1994;Nakai et al, 1993;Pettke et al, 2000), suggesting that aeolian dust in the central North Pacific and the CLP derives from the same source (Sun, 2005). In addition, the uniform Nd isotopic composition since 12 Ma (Pettke et al, 2000), possibly even since the late Eocene (Pettke et al, 2002), precludes a major change in the provenance of the dominant dust component. More recently, Nd-Sr isotopic studies suggest that the dust source region for both the proximal CLP (via near-surface northwest winter monsoon) and the distal North Pacific (via high-altitude westerlies) is the deserts on the northern margin of the Tibetan Plateau, i.e., Taklimakan, Qaidam, Badain Jaran, and Tengger deserts (Chen et al, 2007;Rao et al, 2009).…”

Section: Drying Of the Dust Source Regionmentioning

confidence: 75%