Climate proxies for the last 17.3 ka from Lake Hazar (Eastern Anatolia), extracted by independent component analysis of μ -XRF data

Bibliographic Data

ID21120531
AuthorsZ Bora Ön (0000-0002-8684-3476, Muğla University, corresponding author), Sena Akçer Ön (0000-0002-0708-8629, Muğla University), M Sinan Özeren (0000-0003-2295-4289), Kürşad Kadir Eriş (0000-0002-7440-8709), Alan M Greaves (0000-0002-8004-4702, University of Liverpool), M Namık Çağatay (0000-0003-4677-3802)
Year2018
Volume486
Pages17-28
Publication date2018-08-01
Peer ReviewedYes
Open AccessYes
TypeARTICLE
VenueQuaternary International (JOURNAL)
Journal identifiersISSN: 1040-6182 • E-ISSN: 1873-4553
PublisherElsevier BV (PUBLISHER)
DOI10.1016/j.quaint.2017.08.066
OpenAlexW2755570984
LanguageEN
Citations received9
References cited66

The elemental composition of lake sediment cores is often the result of several independent processes. In this study we attempt to extract statistically independent climate related signals from μ-XRF multi element data of a core drilled from Lake Hazar in Eastern Anatolia, using the independent component analysis (ICA) method. In addition, we analysed ostracod shells for oxygen and carbon isotopes. The ICA method has advantages over traditional dimension reduction methods, such as principal component analysis or factor analysis, because it is based on maximal statistical independence rather than uncorrelatedness, where independence is a stronger property. The Hz11-P03 core, which represents the last 17.3 ka, was recovered from Lake Hazar which, at times, formed the headwaters of the Tigris. Applying the ICA method, we selected two out of six independent components by measuring distance correlation similarity. We propose that one of the selected components can be read as a proxy for temperature and the other for precipitation in this region. Our results indicate that the region was relatively cold and wet during the late glacial, between 17.3 and 14.8 ka BP, and wet and warm during Bølling-Allerød. The lake level dropped below today's level during the Younger Dryas stadial (12.49 and 11.76 ka BP), forming a marked hiatus in the core's stratigraphic record. During the beginning of the Holocene, while precipitation values were high, the temperature gradually increased until 8 ka BP. Between 8 and 5 ka BP, the region was warm but extremely dry. After 5 ka BP, around 3.5 ka BP temperatures suddenly fell, and three abrupt dry phases are observed around 3.5 ka and 2.8 ka and 1.8 ka BP

Geography · Glacial period · Holocene · Physical geography · Precipitation · Principal component analysis · Sediment · Younger Dryas · Archaeology and ancient environmental studies · Geology and Paleoclimatology Research · Marine and environmental studies · Geology · Paleontology