Physico-Chemical Features and Subsurface Nature of Coastal Dunes on Bozcaada Island, NW Turkey

Authors : Mustafa AVCIOĞLU, Ahmet Evren ERGİNAL, Muhammed Zeynel ÖZTÜRK, Alper DEMİRCİ, Yunus Levent EKİNCİ, Murat TÜRKEŞ, Ersin KARABACAK, Ali SUNGUR, Hasan ÖZCAN, Rezzan EKİNCİ, Gülsen ERGİNAL

Pages : 1-15

Doi:10.30897/ijegeo.303171

View : 16 | Download : 8

Publication Date : 2015-03-02

Article Type : Research Paper

Abstract :We studied the composition, vegetation cover, wind regime characteristics and subsurface nature of a coastal dune field on the west coast of Bozcaada Island, NW Turkey. Performing Electrical Resistivity Tomography insert ignore into journalissuearticles values(ERT); technique, we determined that dune sands with a thickness of ~11-13 m cover the underlying Miocene basement, as confirmed by an abrupt increase in resistivity as from lithological boundary. The results demonstrate that foredune terraces and ridges differ from swales from various points of view. The foredune sands are characterized by average contents of over 82% medium to fine-sized angular sands, especially quartz insert ignore into journalissuearticles values(85%);, based on X-ray fluorescence spectroscopy insert ignore into journalissuearticles values(XRF); data, CaCO 3 insert ignore into journalissuearticles values(1.15%); and organic matter insert ignore into journalissuearticles values(0.19%);. On the other hand, swales are composed on average of 59% medium to fine sands, a mixture of silt and clay insert ignore into journalissuearticles values(13%);, very coarse sands and small-size gravels insert ignore into journalissuearticles values(28%);. In addition to the different grain size distribution, swale sediments have conspicuously lesser amounts of SiO 2 insert ignore into journalissuearticles values(78%);, higher amounts of CaCO 3 insert ignore into journalissuearticles values(5.6%); and organic matter insert ignore into journalissuearticles values(0.8%);. Wind climatology analysis showed the predominance of a northerly insert ignore into journalissuearticles values(mainly NNE); near surface wind circulation over Bozcaada throughout the year with high wind speeds of maximum 7.4 m/s. Nevertheless, the existing sand transport and associated development of foredune forms and blowouts in the dune field relates considerably to the bimodal distribution of northerly winds insert ignore into journalissuearticles values(NNW and NNE);. Although the coastal dune area is capped by a variety of dune plants, blowout development is highly active, in particular, on the northeast section of the dune field.
Keywords : Dune sand, electrical resistivity, wind climatology, Bozcaada Island, NW Turkey