Atomic ratio, H:C Atomic ratio, H:C 



0+N+S 



Fig. 3. The chemical composition of fossil organic substances. 



(a) Composition of caustobiolites of the coal — sapropelite series: 1 — cellulose; 

 2 — wood ; 3 — peat ; 4 — lignites ; S — coal ; 6 — striped coals and others ; 7 — anthracites ; 

 S — bedded graphites ; 9 — shungites:2ö — sapropel coals ; 11 — combustible bitumin- 

 ous shales; 12 — sapropels; 13 — carbonified saproponites. 



(b) Demonstrated processes of change of organic substances in the earth crust : 

 1 — composition of the caustobiolites of the coal sapropehte series (K) and bitumens 

 of the oil series; 2 — demonstrated processes of change of organic substances; 

 3 — composition of gaseous hydrocarbons and bitumens of the oil series ; 4 — com- 

 position of caustobiolites of the coal — sapropelite series: Ö — Loss of CO2, H2O 



and others. 



(c) Composition of bitumens of the oil series : 1 — Average composition of hydro- 

 carbons of combustible gas; 2 — average composition of methane oil; 3 — normal 

 type oils; 4 — resinous oils; 5 — asphalts and malthas; 6 — gilsonites; 7 — grahamites; 



•S — impsonites; fl — anthraxolites. 

 The sum of three perpendiculars dropped from any point of the diagram to the 

 sides of the equilateral triangle is a constant value; it is I00°o and corresponds to 

 the sum of the contents in weight (C) + (H) + (O + N + S) in the composition 

 of the organic substance. The weight percentages of carbon, hydrogen, and the 

 sums of oxygen, nitrogen, and sulphur correspond to each of the three perpendi- 

 culars dropped to the sides of the triangle. 



Ta face p. 92. 



