Paleo-Depositional Environment and Coalification Characteristics of Çilhoroz (Çayırlı - Erzincan) Coals

Year 2018, Volume: 3 Issue: 1, 11 - 29, 30.06.2018

Nazan Yalcın Erik Faruk Ay

Abstract

This study has done by petrographic methods in
order to determine the paleo-depositional features and coalification process
characteristics of coal deposits around Çilhoroz in Erzincan basin. Coal
bearing units consists of coal and alternating layers (mainly clay, carbonate
shale, limestone) and it located at the Miocene aged Neftlik Formation at
Çayırlı area. Çilhoroz coal seam demonstrate a dominance of dull and banded
dull lithotypes. The coal is predominated by combined xylitic/attrital
lithotypes and by huminite macerals with inertinite and minor liptinite
macerals. Densinite, attrinite, ulminite and corpohuminite were the most
abundant huminite group macerals, respectively. Inertodetrinite and macrinite
were the dominant inertinite macerals, while sporinite and resinite were the
predominant litpinite macerals. The content of mineral matter (such as clay,
pyrit) is variable but generally low (varying from 1% to 7%), it consists
mostly of quartz, calcite, clay minerals, and pyrite. According to the
proximate and ultimate analyses data indicate that the coal is describe by and
in proportion to low ash (avg. 27%), moisture ingredient (avg. 18%) and total
sulphur content (avg. 7.7). The volatile matter yields and carbon contents are
relatively high, while fixed carbon, sulphur and oxygen contents are average
and hydrogen and nitrogen contents are low. The mean huminite reflectance
values of samples (Ro, %) ranged from 0.42 to 0.50, and these coals are
bituminous B/C coal according to ASTM classification. Based on the GI-TPI,
VI-GWI facies diagrams, the Çilhoroz coal formed in the limnic environment,
with the accumulation of dominated vegetable matter and conditions up to
rheotrophic to mesotrophic.

Keywords

Tertiary coals, paleo-environment, petrography, Çayırlı coal, Erzincan Basin

Çilhoroz (Çayırlı-Erzincan) Kömürlerinin Paleo-Çökelim Ortamı ve Kömürleşme Süreci Özellikleri

Abstract

Bu çalışma Erzincan havzasında, Çilhoroz civarındaki kömürlü istiflerin
paleo-ortam özellikleri ve kömürleşme süreçlerinin belirlenmesi amacıyla
petrografik yöntemlerle gerçekleştirilmiştir. Kömürlü istif, kömür ve
ardalanmalı tabakalardan (başlıca kil, karbonatlı şeyl, kireçtaşı) oluşur ve
Çayırlı sahasında Miyosen yaşlı Neftlik Formasyonu taban seviyelerinde
bulunur.  Çilhoroz kömür damarı egemen
olarak mat, bantlı mat litotiplerini göstermektedir. Kömür ksilitik/detritik
litotipler ve hüminit maseralleri, ikinci olarak da inertinit maseralleri ile
çok düşük miktarda liptinitlerden oluşmaktadır. Densinit, attrinit, ulminit ve
korpohuminit sırasıyla en bol bulunan huminit grubu maseralleridir.
Inertodetrinit ve makrinit inertinit grubunda egemenken, liptinit grubunda da
sporinit ve resinitler baskın maserallerdir. Mineral madde içeriği (kil ve
pirit gibi) ise genellikle değişken ve düşük (%1-7 arasında) olup, çoğunlukla
kuvars, kalsit, kil mineralleri ve piritten oluşur. Kısa ve elementer analiz
verilerine göre kömür düşük kül (ort. %27), nem (ort. %18) ve kükürt
içeriklidir (ort. % 7.7). Uçucu madde ve karbon bileşimi ortalama değerlerde
iken, hidrojen ve azot içeriği düşüktür. Ortalama hüminit yansıma değerleri
(Ro, %) 0.42-0.50 arasında değişmektedir ve ASTM sınıflamasına göre bitümlü B/C
tipi kömürdür. GI-TPI, VI-GWI fasiyes diyagramlarına göre Çilhoroz kömür damarı
limnik ortamda, başlıca bitkisel maddelerin birikimi ile retrofik-mesotrofik
şartlarda oluşmuştur.

Keywords

Tersiyer kömürleri, paleo-ortam, petrografi, Çayırlı kömürü, Erzincan Havzası

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