[1] 1.Barrick R. C.,Hedges J. I. and Peterson M. L.(1980) Hydrocarbon geochemistry of the Puget Sound region-I.Sedimentary acydic hydrocarbons. Geochim. Cosmochim. Acta 44. 1349-1362.

2.Barrick R. C. and Hedges J. I. (1981) Hydrocarbon geochemistry of the Puget Sound region-1 .Sedimentary diter-penoid, steroid and triterpenoid hydrocarbons. Geochim. Cosmochirn. Acta 45. 381-392.

3.Belt S. T.,Cooke D. A.,Hird S. J. and Rowland S. (1994) Structural Determination of a highly branched Czs sedi-mentary isoprenoid biomarker by NMR spectroscopy and Mass spectrometry. J. ChPm. Snc.,Chem. Commurz. 2077-2078.

4.Cranwell P..A. (1982) Lipids of aquatic sediments and sedimentary particulates. Prog. Lipid Res. 21,271-308.

5.Hird S. J.,Evans R. and Rowland S. J. (1992) Isolation and characterization of sedimentary and synthetic highlybranched C20 and C25 monoenes. Mar. Chem. 37,117-129.

6.Hoefs M. J. L.,Sinninghe Damste J. S. and de Leeuw J. W. (1995) A novel Cas highly branched isoprenoid polyene in recent Indian (kean sediments. prg Geochem. 23, 263-267.

7.Kohnen M, E. L.,Sinninghe Damste J. S.,Rullkotter J.,ten Haven H. L. and de Leeuw J. W. (1990) Origin and transformation of C25 and C30 highly branched isoprenoid sulphur compounds, further evidence for the formation of or-ganically bound sulphur during early diagenesis. Gexhim. Cosrnochim. Acta 54,3053-3063.

8.Nichols P. D.,Volkman J. K.,Palmisane A. C.,Smith G. A. and White D. C.(1988) Occurrence of an isoprenoid C25 diunsaturated alkene and high neutral lipid content in Antarctic sea-ice diatom communities. J. Phycol. 24, 90-96.

9.Requejo A. G. and Quinn J. G. (1983) Geochemistry of C25 and C30 biogenic alkenes in sediments of the Narragansett Bay estuary. Geochim. Cosmochim. Acta 47, 1075-1090.

10.Requejo A. G.,Quinn J. G.,Gearing J. N. and Gearing P. J. (1984) C25 and C30 biogenic alkenes in a sediment core from the upper anoxic basin of the Pettaquamscutt River (Rhode Island, U. S. A.).Org. Geochem. 7.1-10.

11.Robson J. N. and Rowland S. J. (1986 ) Indentification of novel widely distributed sedimentary acycGc sesterter-penoids. Nazure 324. 561-563.

12.Robson J. N. and Rowland S. J.(1988a) Synthesis of a highly branched Csosedimentary hydrocarbon. Tetrahedron Lett. 29, 3837-3840.

13.Robson J. N. and Rowland S. J. (19886) Biodegradation of highly branched isoporenoid hydrocarbons; A possible ex-planation of sedimentary abundance. In Aduances in Ch}ganic Geochemistry 1987, Chog. Georhern. 13. 691-695.

14.Rowland S. J.,Yon D. A.,Lewis C. A. and Maxwell J. R. (1985 ) Ocurrence of 2. 6. 10-trimethyl-7(3-methylbutyl)-dodecane and related hydrocarbons in the green alga Enteromorpha prolifera and sediments. Org.Geochem. 8, 207-213.

15.Rowland S. J. and Robson. J. N. (1990) The widespread occurrence of highly branched acyclic C20. C25 and C30 hy-drocarbons in recent sediments and biota-a review. Mar. Erruvon. Res. 30.191-216.

16.Sinninghe Damste J. S.,Van Koert E. R.,Kock-van Dalen A. C.,de leeuw J. W. and Schenck P. A. (1989) Char-acteri7ation of highly branched isoprenoid thiophenes occurring in sediments and immature crude oils. Org. Geochem.

17.Sinninghe Damste J. S. and Rijpstra W. I. C. (1993) Identification of a novel C25 highly branched isoprenoid thiophenein sediments. Org. Geochcm. 20, 327-331.

18.Volkman J. K.,Barrett S. M. and Dunstan G. A. (1994 ) C25 and C30 branched isoprenoid alkenes in laboratorycultures of two marine diatoms. (kg. Geochem. 21,407-413.

19.Yon D. A.,Ryback G. and Maxwell J. R. (1982) 2. 6. 10-Trimethyl-7(3-methylbutyl) dodecane. a novelsedi-mentary biological marker compound, Tetrnhedrrm L.ett. 23, 2143-2146.

20.Yruela I.,Barbe A. and Grimalt J. O. (1990) Determination of double bond position and geometry in Linear andhighly branched hydrocarbons and fatty acids from gas chromatography-mass spectrometry of epoxides and diols gen-erated by stereospecific resin hydration. J. Chrnmmtoqr. Sci. 28. 421-427.