Archive for the ‘Quaternary geology’ category

Homo erectus skull dating with cosmogenic nuclides in Denizli

January 21, 2014

Newly  obtained cosmogenic ages challenge our current knowledge of the Anatolian Homo erectus dispersal. A new discovery within a travertine quarry from Denizli was made by Cihat Alçiçek from Pamukkale University and his colloquies, Lebatard et al. (published in EPSL vol. 390). The burial ages determined on pebbles from conglomeratic levels framing travertine unit that bears the fossil. “The actual age of the fossils is likely to be in the 1.1–1.3 Ma range”, they report. This date is in close agreement with the paleoanthropological conclusions based on morphometric comparisons. The Turkish Homo erectus belongs to the Chinese and African fossil groups, and is different from Middle and Upper Pleistocene specimens. It attests to the antiquity of human occupation of the Anatolian Peninsula. please refer to http://dx.doi.org/10.1016/j.epsl.2013.12.031 for more information.

Screen shot 2014-01-21 at 11.55.58skull

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Tephra deposits in the western Anatolia

January 27, 2012

Source: geology.sdsu.edu

Kazancı et al. from Ankara University published a paper in Global and Planetary Change about a tephra deposits in the Çardak area of Denizli. Its formation time is between 5380 ± 90 and 2395 ± 65 yrs cal BP according to radiocarbon dating of two palaeosol layers within the colluvium. These discoveries showed that very strong volcanic eruption occurred in the Aegean Sea apart from the Santorini explosion. Please refer to http://dx.doi.org/10.1016/j.gloplacha.2011.09.007

 

Fossil elephants in Turkey

January 27, 2012

Albayrak and Lister have been published a study in Quaternary International about the first detailed study of elephant remains from five localities. The radiocarbon dates indicate the ages to 3500 BP, the range of Asian elephant extended as far west as south-east Turkey. This interesting study can be found at http://dx.doi.org/10.1016/j.quaint.2011.05.042

Source: west-runton.ukfossils.co.uk

Sedimentary deposits in the Istanbul’s Byzantine harbour

January 27, 2012

Bony et al. published an interesting study in Quaternary International about a Byzantine harbour (Theodosian harbour) which has been uncovered during excavations in Istanbul. The stratigraphic sequence goes back to 7000 BP. In the marine part of the sedimentary sequence, the authors interpreted high-energy deposit as tsunami deposits and related to the earthquake of 557 AD. You can find more info at http://dx.doi.org/10.1016/j.quaint.2011.03.031.

Source: nautarch.tamu.edu

Remarkably extensive glaciation in Turkey near the Pleistocene-Holocene boundary

December 26, 2011

A new paper was published in GSA’s Journal of Geology by Zreda and others in November 2011. This is their media paragraph published in the journal’s web site: “Looking at how climate changed in the geological past can provide a useful perspective for studying modern climate change and for predicting climate changes in the next century. Dr Marek Zreda of the University of Arizona and his colleagues used mountain moraines to reconstruct the former glaciers and to determine climatic changes in Turkey at the beginning of the Holocene, the current interglacial epoch. They found that the glaciers were unusually large for that time, with snow lines lower than today by more than 1400 meters, implying a temperature 9°C lower than modern long-term average temperature. The main glacier melting phase lasted 500 years during which the ice margin retreated at the average rate of 1700 m per century, which is higher than modern gracier retreat rates computed over comparable time. This corresponds to the temperature increase at the rate of 1.4°C per century, which exceeds the global warming trend of the past century, 0.6°C, showing that natural causes can lead to fast and large climate changes, and that the magnitude and the rate of climate change observed in the past century are not unprecedented.” Please see more details and the paper here doi:10.1130/G32097.1

Holocene climate change in central Turkey

December 25, 2011

Last 6000 years climate record from Tecer Lake in central Turkey were published in Holoceneby Kuzucuoğlu et al. According to the mineralogy and grain-size distribution of lake sediments, during the mid-Holocene transition, intense droughts occured at the end of the sixth, fifth and fourth millennia BP. The characteristics of some climatic phases at Tecer seem specific to the location of the sequence which, when compared with other sites in the eastern Mediterranean, may record variations in the extent of different climatic systems. Please refer to doi: 10.1177/0959683610384163

A new tree-ring data from western Anatolia

February 8, 2011

Kose et al. 2011 have published a new data set on May-June precipitation of the Late Holocene obtained from 17 black pine tree-rings. Their study was published in the Journal of Quaternary Research. May–June precipitation reconstructions contain mostly one-year and, less commonly, two-year drought events. The longest consecutive dry period was in between 1925–1928 AD. The driest year was 1887. The wettest years for the entire western Anatolia were determined to be AD 1835, 1876, 1881 and 1901. They claimed that the study provides a better understanding of agricultural drought and management of regional water resources. For more information, please refer to doi:10.1016/j.yqres.2010.12.005