Depositional Properties and Paleoclimate of a Middle-Upper Pleistocene Fan Delta Sequence in the Bor Plain, Central Anatolia, Turkey

Türkan Bayer Altın; Zehra Karakaş; Bekir Necati Altın; Mine Sezgül Kayseri Özer

Makale detayları

Depositional Properties and Paleoclimate of a Middle-Upper Pleistocene Fan Delta Sequence in the Bor Plain, Central Anatolia, Turkey

Yazarlar:

Türkan Bayer Altın | Zehra Karakaş | Bekir Necati Altın | Mine Sezgül Kayseri Özer

Yayıncı:

Istanbul University

Ana Başlıklar:

Fiziksel Coğrafya ve Çevre Jeolojisi (Diğer)

Dergi:

Coğrafya Dergisi Issue 48, pp.65-82

Belge Tipi:

Makale

Yayın Tarihi:

5/2024

Belge Dili:

İngilizce

Document ID (Org No.):

2001324939

pISSN:

1305-2128

Anahtar kelimeler:

Özet:

 The Bor Plain, which is located in the Middle Kızılırmak subregion of the Central Anatolia Region, extends 14 km toward the west of Niğde. The fan delta deposition system in the southwest of the Bor Plain was formed on the fault-controlled foothills of Mt. Keçiboyduran. The fandelta sequence shows that a paleolake formed during a phase because of the mineralogical content and frequently changing facies. Additionally, clay minerals and herbaceous plants reflecting humid and arid climatic conditions illustrate the lake-level changes. Six changes in the lake level occurred from marine isotope stage MIS 7 to MIS 5. Three major high stands occurred in the paleolake at the lowest and middle parts of the sequence. The first high stand was a stepwise transgression between 240 and 230 ka., and the second high stand was between 200 and 195 ka. The third high stand was characterized by a short transgression at 182 ka. After this stage, the lake receded significantly at 127 and 105 ka, indicating climatic control over the water level changes. In the transition from the Middle to Late Pleistocene, a revival of volcanic activity in the Leşkeri monogenic volcanic mass released volcanic material, affecting sedimentation. Volcanic rocks increase dramatically in the upper section of the fandelta during an interval that coincides with low lake-level fluctuations.

 The Bor Plain, which is located in the Middle Kızılırmak subregion of the Central Anatolia Region, extends 14 km toward the west of Niğde. The fan delta deposition system in the southwest of the Bor Plain was formed on the fault-controlled foothills of Mt. Keçiboyduran. The fandelta sequence shows that a paleolake formed during a phase because of the mineralogical content and frequently changing facies. Additionally, clay minerals and herbaceous plants reflecting humid and arid climatic conditions illustrate the lake-level changes. Six changes in the lake level occurred from marine isotope stage MIS 7 to MIS 5. Three major high stands occurred in the paleolake at the lowest and middle parts of the sequence. The first high stand was a stepwise transgression between 240 and 230 ka., and the second high stand was between 200 and 195 ka. The third high stand was characterized by a short transgression at 182 ka. After this stage, the lake receded significantly at 127 and 105 ka, indicating climatic control over the water level changes. In the transition from the Middle to Late Pleistocene, a revival of volcanic activity in the Leşkeri monogenic volcanic mass released volcanic material, affecting sedimentation. Volcanic rocks increase dramatically in the upper section of the fandelta during an interval that coincides with low lake-level fluctuations.

 The Bor Plain, which is located in the Middle Kızılırmak subregion of the Central Anatolia Region, extends 14 km toward the west of Niğde. The fan delta deposition system in the southwest of the Bor Plain was formed on the fault-controlled foothills of Mt. Keçiboyduran. The fandelta sequence shows that a paleolake formed during a phase because of the mineralogical content and frequently changing facies. Additionally, clay minerals and herbaceous plants reflecting humid and arid climatic conditions illustrate the lake-level changes. Six changes in the lake level occurred from marine isotope stage MIS 7 to MIS 5. Three major high stands occurred in the paleolake at the lowest and middle parts of the sequence. The first high stand was a stepwise transgression between 240 and 230 ka., and the second high stand was between 200 and 195 ka. The third high stand was characterized by a short transgression at 182 ka. After this stage, the lake receded significantly at 127 and 105 ka, indicating climatic control over the water level changes. In the transition from the Middle to Late Pleistocene, a revival of volcanic activity in the Leşkeri monogenic volcanic mass released volcanic material, affecting sedimentation. Volcanic rocks increase dramatically in the upper section of the fandelta during an interval that coincides with low lake-level fluctuations.

 İç Anadolu Bölgesinin Orta Kızılırmak bölümünde bulunan Bor Ovası, Niğdenin batısına doğru 14 km uzanır. Ovanın güneybatısındaki yelpaze deltası, Keçiboyduran Dağının fay kontrollü eteğinde oluşmuştur. Fan delta, mineralojik içerik ve sık sık değişen fasiyes nedeniyle bir faz sırasında eski bir göl ortamında oluştuğunu göstermektedir. Ayrıca nemli ve kurak iklim koşullarını yansıtan kil mineralleri ve otsu bitkiler göl seviyesindeki değişimleri göstermektedir. Deniz izotop aşaması MIS 7den MIS 5e kadar göl seviyesinde altı kez değişiklik meydana geldiği anlaşılmaktadır. İstifin en alt ve orta kısımlarında eski göl ortamında üç büyük yüksek basamak meydana gelmiştir. İlk yüksek basamak, 240 ile 230 ka arasında ve İkinci yüksek basamak 200 ile 195 ka arasındadır. Üçüncü yüksek basamak 182 kada görülmektedir. Bu aşamadan sonra göl 127 ka ve 105 ka da önemli ölçüde gerilemiştir. Bu durum su seviyesi değişiklikleri üzerinde iklim kontrolünün olduğunu göstermektedir. Ayrıca Orta Pleyistosenden Geç Pleyistosene geçişte, Leşkeri volkanik kütlesinden çıkan materyal sedimantasyona etki etmiştir. Bu nedenle volkanik kayaçlar, düşük göl seviyesi dalgalanmalarına denk gelen bir aralıkta fan deltanın üst kesiminde önemli ölçüde artar.

Makale detayları

Depositional Properties and Paleoclimate of a Middle-Upper Pleistocene Fan Delta Sequence in the Bor Plain, Central Anatolia, Turkey

Yazarlar:

Türkan Bayer Altın | Zehra Karakaş | Bekir Necati Altın | Mine Sezgül Kayseri Özer

Yayıncı:

Istanbul University

Ana Başlıklar:

Fiziksel Coğrafya ve Çevre Jeolojisi (Diğer)

Dergi:

Coğrafya Dergisi Issue 48, pp.65-82

Belge Tipi:

Makale

Yayın Tarihi:

5/2024

Belge Dili:

İngilizce

Document ID (Org No.):

2001324939

pISSN:

1305-2128

Fan delta

Paleoclimate

MIS7Fan delta

Plaeoiklim

MIS7

Sayı

Makale detayları

Depositional Properties and Paleoclimate of a Middle-Upper Pleistocene Fan Delta Sequence in the Bor Plain, Central Anatolia, Turkey

Yazarlar: Türkan Bayer Altın | Zehra Karakaş | Bekir Necati Altın | Mine Sezgül Kayseri Özer

Yayıncı: Istanbul University

Ana Başlıklar: Fiziksel Coğrafya ve Çevre Jeolojisi (Diğer)

Dergi: Coğrafya Dergisi Issue 48, pp.65-82

Belge Tipi: Makale

Yayın Tarihi: 5/2024

Belge Dili: İngilizce

Document ID (Org No.): 2001324939

pISSN: 1305-2128

Fan delta

Paleoclimate

MIS7Fan delta

Plaeoiklim

MIS7

Sayı

Yazarlar:

Türkan Bayer Altın | Zehra Karakaş | Bekir Necati Altın | Mine Sezgül Kayseri Özer

Yayıncı:

Istanbul University

Ana Başlıklar:

Fiziksel Coğrafya ve Çevre Jeolojisi (Diğer)

Dergi:

Coğrafya Dergisi Issue 48, pp.65-82

Belge Tipi:

Makale

Yayın Tarihi:

5/2024

Belge Dili:

İngilizce

Document ID (Org No.):

2001324939

pISSN:

1305-2128