A Computer Programme for Geothermometer's Calculations for the Estimation the Reservoir Tempcraiurc of the Gcothermal Watcrs

Yıl 2004, Cilt: 28 Sayı: 2, 1 - 12, 01.11.2004

Müfit Şefik Doğdu

Öz

Geothermometers are one ofthe most important methods used for determining the geothermal water reservoir temperature. Chemical content ofthe thermal water that was acquired by the waterrock interaction is used in the geothermometer equations. Determination of possible reservoir temperature ofthe thermal water is quite important for development and operation of the thermal waters. in spite ofbeing lots of geothermometer type like cation, silica, gas and isotope, generally cation and silica geothermometers arepreferred because their analyses and evaluations are easy. in the scope ofthis study, a computer programme has been prepared by using ofthe Microsoft Visual Basic 6.0 programming language and aim of this programme is determining the thermal water reservoir temperature by silica and cation geothermometer equations. Majör ion order which denotes the water type; majör ion balance which indicates the accuracy ofthe water analyses; and maturity index which indicates the application ofthe Na-K geothermometers are suitable or not to thermal water are determined by this programme in addition to the geothermometer calculations. Appropriateness of the reservoir rock mineral composition to the based mineral used in geothermometer equations, the chemical equilibrium behveen water and rock, cold water mixing, chemical changes in the thermal water when it was ascending, etc. must always be taken into consideration during the geothermometer applications, in terms ofevaluations and reliability.

Anahtar Kelimeler

geothermal water, geothermometer, reservoir temperature.

Jeotermal Suların Rezervuar Sıcaklığının Tahmininde Kullanılan Jeotermometre Hesaplamaları İçin Bilgisayar Programı

Öz

Jeotermal suların rezervuar sıcaklığının belirlenmesinde kullanılan en önemli yöntemlerden biri jeotermometrelerdir. Jeotermometre eşitliklerinde termal suyun rezervuar kayaç etkileşimi ile kazandığı kimyasal içerik kullanılmaktadır. Rezervuar sıcaklığının kaç derece olabileceğini belirlemek, termal suyun ekonomik olarak işletilmesi ve geliştirilmesi açısından oldukça önemlidir. Katyon, silis, gaz, izotop vb. bir çok jeotermometre türü olmasına karşın örneklemesi, analizi ve değerlendirilmesi kolay olduğundan dolayı genellikle rezervuar sıcaklığının tahmininde katyon ve silis jeotermometreleri tercih edilmektedir. Bu çalışma kapsamında Microsoft Visual Basic 6.0 programlama dilinde hazırlanan bilgisayar programının amacı katyon ve silis jeotermometre eşitlikleri ile termal suyun rezervuar sıcaklığını belirlemektir. Jeotermometre sonuçlarının yanı sıra suyun tipini gösteren majör iyon sıralaması, analiz doğruluğunu belirten majör iyon dengesi ve termal suya Na-K jeotermometresinin uygulanıp uygulanamayacağının belirteci olan olgunluk indeksi de bu program tarafından hesaplanmaktadır. Jeotermometrelerin uygulanmasında ve sonuçlarının değerlendirilmesinde, jeotermometrenin temel aldığı mineral bileşiminin alandaki rezervuar kayaç bileşimine uygunluğu, termal su ile kayaç arasında kimyasal dengenin sağlanmış olması, termal suya soğuk suyun karışması, termal suyun yüzeye yükselirken uğradığı kimyasal değişikler vb. gibi süreçler hesaplanan rezervuar sıcaklığının güvenilirliği açısından daima göz önünde bulundurulmalıdır.

Anahtar Kelimeler

jeotermal su, jeotermometre, rezervuar sıcaklığı.

Kaynakça

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