DOI: 10.1016/j.palaeo.2015.08.014
论文题名: Link between cyclic eustatic sea-level change and continental weathering: Evidence for aquifer-eustasy in the Cretaceous
作者: Wendler J.E. ; Wendler I. ; Vogt C. ; Kuss J.
刊名: Palaeogeography, Palaeoclimatology, Palaeoecology
ISSN: 0031-0182
出版年: 2016
卷: 441 起始页码: 430
结束页码: 437
语种: 英语
英文关键词: Cenomanian
; Greenhouse climate
; Hydrological cycle
; Sequence stratigraphy
; Terrigenous minerals
; Turonian
英文摘要: Cyclic fluctuations in global sea level during epochs of warm greenhouse climate have remained enigmatic, because absence or subordinate presence of polar ice during these periods precludes an explanation by glacio-eustatic forcing. An alternative concept suggests that the water-bearing potential of groundwater aquifers is equal to that of ice caps and that changes in the dynamic balance of aquifer charge versus discharge, as a function of the temperature-related intensity of the hydrological cycle, may have driven eustasy during warm climates. However, this idea has long been neglected for two reasons: 1) the large storage potential of subsurface aquifers was confused with the much smaller capacity of rivers and lakes and 2) empirical data were missing that document past variations in the hydrological cycle in relation to eustasy. In the present study we present the first empirical evidence for changes in precipitation, continental weathering intensity and evaporation that correlate with astronomically (long obliquity) forced sea-level cycles during the warmest period of the Cretaceous (Cenomanian–Turonian). We compare sequence-stratigraphic data with changes in the terrigenous mineral assemblage in a low-latitude marine sedimentary sequence from the equatorial humid belt at the South-Tethyan margin (Levant carbonate platform, Jordan), thereby avoiding uncertainties from land–ocean correlations. Our data indicate covariance between cycles in weathering and sea level: predominantly chemical weathering under wet climate conditions is reflected by dominance of weathering products (clays) in deposits that represent sea-level fall (aquifer charge > discharge). Conversely, preservation of weathering-sensitive minerals (feldspars, epidote and pyroxenes) in transgressive sediments reflects decreased continental weathering due to dryer climate (aquifer discharge > charge). Based on our results we suggest that aquifer-eustasy represents a viable alternative to glacio-eustasy as a driver of cyclic 3rd-order sea-level fluctuations during the middle Cretaceous greenhouse climate, and it may have been a pervasive process throughout Earth history. © 2015 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/68702
Appears in Collections: 过去全球变化的重建
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作者单位: Department of Geosciences, Bremen University, P.O. Box 330440, Bremen, Germany; Crystallography/Central Laboratory for Applied Material Sciences (ZEKAM), Department of Geosciences, Bremen University, P.O. Box 330440, Bremen, Germany
Recommended Citation:
Wendler J.E.,Wendler I.,Vogt C.,et al. Link between cyclic eustatic sea-level change and continental weathering: Evidence for aquifer-eustasy in the Cretaceous[J]. Palaeogeography, Palaeoclimatology, Palaeoecology,2016-01-01,441