Table 3 List of the compounds detected by GC–MS in all the investigated samples

Tricyclic terpanes

1

TR23

tricyclic terpane C 23

Tetracyclic terpanes

2

TET24

tetracyclic terpane C24

Trisnorhopanes

3

Ts

18α(H),21β(H)-22,29,30-Trisnorhopane

4

Tm

17α(H),18α(H),21β(H)-22,29,30-Trisnorhopane

Bisnorhopanes

5

H28

17α(H),18α(H),21β(H)-28,30-Bisnorhopane

Norhopanes

6

H29

17α(H),21β(H)-30-Norhopane

7

M29

17β(H),21α(H)-30-Norhopane

Hopanes

8

H30

17α(H),21β(H)-Hopane

9

M30

17β(H),21α(H)-Hopane

Homohopanes

10

H31S

22S-30-Homohopane

11

H31R

22R-30-Homohopane

Gammacerane

12

GAM

Gammacerane

Bishomohopanes

13

H32S

22S-30,31-Bishomohopane

14

H32R

22R-30,31-Bishomohopane

Trishomohopanes

15

H33S

22S-17α(H),21β(H)-30,31,32-Trishomohopane

16

H33R

22R-17α(H),21β(H)-30,31,32-Trishomohopane

Tetrakishomohopanes

17

H34S

22S-17α(H),21β(H)-30,31,32,33-Tetrakishomohopane

18

H34R

22R-17α(H),21β(H)-30,31,32,33-Tetrakishomohopane

Pentakishomohopanes

19

H35S

22S-17α(H),21β(H)-30,31,32,33,34-Pentakishomohopane

20

H35R

22R-17α(H),21β(H)-30,31,32,33,34-Pentakishomohopane