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A total of 30 core samples of organic matter-rich Lower Toarcian shale (Posidonia Shale) were geochemically analyzed to study systematic changes in the quantitative and qualitative composition of specific biomarkers at different thermal maturities ranging from 0.48 to 1.45% vitrinite reflectance (VRr). The samples are derived from 5 wells (Hils Syncline, NW Germany) each representing a different level of maturation (0.48, 0.68, 0.73, 0.88, 1.45 %VRr). In NW Germany, Posidonia Shale was deposited under marine, oxygen-deficient bottom water containing initially high amounts of TOC (above 10%) and marine type I-II kerogen. Upon maturation, organic carbon has been lost and hydrogen index values have decreased. Biomarker ratios reflecting this maturation very well include ratios of short over long-chain n-alkanes, ratios of pristane and phytane over nC17 and nC18, Ts/(Ts + Tm), C29Ts/(C29Ts + C29H), ratios based on DMDBTs, and TA(I)/TA(I + II) ratios (triaromatic steroids). The evolution of different steroid-, hopane-, naphthalene-, phenanthrene- and dibenzothiophene-related parameters is documented and compared to literature. Concentrations of individual hydrocarbons were measured in order to obtain quantitative data on biomarker abundance and their evolution upon maturation. Whereas there is a general trend of increasing biomarker content from immature (0.48 %VRr) to early mature (0.68 %VRr) conditions and of decreasing biomarker content with maturation from 0.68 to 0.88 %VRr, there are some exceptions from this trend, especially at low levels of maturity. Almost no polycyclic biomarkers were detected at the highest maturity level of 1.45 %VRr in well Haddessen, where n-alkanes and aromatic hydrocarbons are predominant. The overall pattern of polycyclic biomarker abundance is not only determined by isomerization and aromatization processes, but mainly by preferential degradation of thermally less stable biomarkers leading to the observed modifications of biomarker maturity parameters. Furthermore, outer and inner sections from the 10 cm wide cores were compared in order to find out, whether 40 years of dry storage in a core repository affected the biomarker parameters. No significant and systematic differences have been observed, with exception of the most mature Haddessen well, where low molecular weight n-alkanes (

Six samples of Lower Jurassic mudstones (uppermost Pliensbachian, uppermost Lias δ) from boreholes drilled at the southwestern rim of the Hils Syncline (Lower Saxony Basin, NW-Germany), covering a thermal maturity series ranging from immature to overmature, were analyzed to gain insight into the chemical structure and alteration of bisaccate pollen during maturation as well as the differences in results from various analytical methods. Laser-pyrolysis–gas chromatography–mass spectrometry (La-Py–GC–MS) and micro-Fourier transform infrared (μ-FTIR) spectroscopy applied to handpicked bisaccate pollen, and Curie Point-Py (CP-Py–GC–MS) and FTIR spectroscopy applied to sieve-fractionated kerogen concentrate from the same samples indicated considerable differences in composition. Ratios of the main compound groups, e.g. O containing components, aliphatic hydrocarbons and aromatic hydrocarbons, plotted vs. maturity showed systematic changes in composition with maturation. The study also focussed on the comparability of micro- and macroscale spectroscopic and Py methods. The results from FTIR analysis and μ-FTIR analysis, as well as those from La-Py–GC–MS, showed similar trends, e.g. defunctionalization and increasing aromatization, which mostly agree with common knowledge about the changes in the structure of organic matter, whereas the results from CP-Py–GC–MS showed wide differences, especially at higher stages of maturity, i.e. a strong increase in aliphatic vs. aromatic hydrocarbons. Together, the results indicate that both IR spectroscopy and Py–GC–MS are suitable for studying the alteration of palynomorphs during maturation and their complementary use is recommended for comprehensive characterization of alteration.

Future enrichment of atmospheric CO2 and its effect on ecosystems were studied using grassland free air CO2 enrichment (FACE) experiments. Plant waxes have been shown to be directly modified under elevated CO2 concentration. Lipids, as major components of plant waxes, are important constituents of plant surfaces and their position at the plant/atmosphere interface makes them susceptible to environmental change. The main focus of this study was to improve knowledge about modifications to stable carbon isotopic (δ13C) values of individual lipids within plant biomass and soils as a result of the increased atmospheric CO2 concentration, implying an addition of 13C labelled CO2. The isotopically labelled biomass facilitates turnover time determination of lipids in soils due to the direct comparison of identical plants grown under ambient and 13C-depleted atmospheric conditions. We demonstrate which lipids were influenced by modified CO2 concentration and how the lipid isotopic values of plant biomass and soil were influenced under elevated vs. ambient CO2 conditions. Most plant carboxylic acids and alkanes were uniformly depleted in 13C by ca. 6‰ when compared to plant biomass bulk isotope values. In soil, short chain carboxylic acids (

The occurrence and distribution of alkyl naphthalenes and alkyl phenanthrenes in 39 Late Palaeozoic coal and sediment samples, containing predominantly terrestrial organic matter, is related to thermal maturity and biological source input. This study investigates the relationship between aromatic hydrocarbons and the corresponding aldehydes, ketones, carboxylic acids and dicarboxylic acids based on the naphthalene skeleton. It is suggested that alkyl naphthalenes are oxygenated in the sediments. The behaviour of alkyl phenanthrenes and their oxygenated analogues is discussed in this context. Alkyl naphthalenes and phenanthrenes were abundant in all samples. The low polarity nitrogen, sulfur and oxygen compound fraction was characterised by the presence of alkyl naphthaldehydes and naphthyl ketones for the majority of the samples. The presence of naphthalene carboxylic acids and anthracene/phenanthrene carboxylic acids was restricted to samples of relatively enhanced maturity (vitrinite reflectance, Rr, 0.67–1.26%), with one exception. The correlations between the different classes of compounds based on the naphthalene skeleton led to the hypothesis that, within the maturity range investigated, aldehydes and ketones were readily formed from the corresponding aromatic hydrocarbons, while the carboxylic acids were formed at elevated maturity. For alkyl naphthalene dicarboxylic acids, two formation pathways are suggested, because of two different distribution patterns. A direct correlation of these dicarboxylic acids with the occurrence of other compounds having a naphthalene skeleton was not apparent.

Anhydrous non-isothermal heating experiments were conducted under controlled compressive stress on cylindrical plugs of six oil shales from Permian through Miocene age. The objectives of this study were to investigate molecular and compound class fractionation during petroleum generation and expulsion and to highlight causes of compositional variations due to primary migration from source rocks. Molecular compositions of n-alkanes, triterpanes, methylphenanthrenes and fatty acids of the original samples (initial bitumen), the samples after pyrolysis (residual bitumen) and the expelled products were compared. Acyclic alkanes were preferentially expelled with compositions depending on source kerogen and partial evaporative loss from the open experimental system expulsion. No substantial molecular fractionation within various compound classes or preferential primary migration of n-alkanes relative to acyclic isoprenoids occurred. Cyclic triterpanes and aromatic hydrocarbons were found only in small concentrations in the expelled bitumen indicating preferential retention relative to acyclic alkanes. Palmitic (C16) and stearic (C18) acids occurred as dominant compounds in the initial and residual bitumen. In the expelled bitumen they constitute virtually the only fatty acid species, indicating that expulsion efficiency is strongly dependent on concentration and generation intensity.

Comprehensive GC/MS analysis was applied to both the mobile liquid phase (seepage water) and the immobile solid matter of discrete layers derived from a waste deposit landfill. The vertical distribution of organic compounds supports information on the transport, transfer and transformation processes with depth and, consequently, with time. Numerous low molecular weight organic contaminants of natural and xenobiotic origin were identified and partially quantified. Several were selected to act as molecular indicators for different processes. Interpretation of their occurrence and concentration profiles (considering possible waste sources) and their molecular properties allowed us to (i) differentiate immobile and mobile fractions, (ii) reveal restrictions in the vertical transport by transfer processes between particulate and water phase, (iii) identify dynamic accumulations of individual contaminants and (iv) estimate approximate residence times. In addition, intensive degradation processes were pointed out for the natural fraction of the organic matter by way of determination of specific transformation products. Besides the transformation of natural components, transformation of numerous xenobiotics was recognised. In particular, with respect to an important group of contaminants, the phthalate-based plasticisers, a detailed view of (i) the influence of transfer and transport phenomena on transformation processes as well as (ii) the consecutive appearance of different degradation steps in both seepage water and solid waste was pointed out. The information provides a valuable base for the prediction of the long term behaviour of organic contaminants in waste deposit landfills.

Hydrocarbons extracted from the Tertiary age coals from the Lower Suban seam, South Sumatra Basin, Indonesia have been investigated using gas chromatography (GC) and combined gas chromatography/mass spectrometry (GC/MS). Low rank (vitrinite–huminite reflectance ∼0.41–0.45%) coals from the Tambang Air Laya mine represent different maceral assemblages of an ideal succession of ombrogenous palaeo-peat development in a vertical section. High rank coals (vitrinite reflectance ∼1.42–5.18%) from the Suban mine have been thermally metamorphosed by an andesitic intrusion. Variations in the distributions of n -alkanes, isoprenoids and saturated and aromatic biomarkers in the low rank coals reflect variations in local source input and palaeomire conditions. Terpenoid biomarkers, such as cadinane- and eudesmane-type sesquiterpenoids and oleanane- and ursane-type triterpenoids, indicate the predominance of angiosperm plants in the palaeomire, particularly Dipterocarpaceae . The distribution of hopanoids is affected by the organic facies of the coal and their maturity, and correlates with the palaeomire evolution as derived from petrological studies. Close to the igneous intrusion, rapid thermal stress has destroyed most of the biomarkers, but variations in n -alkane distributions, attributable to palaeomire conditions, remain. Reversals in the trends for molecular parameters based on aliphatic hydrocarbons ( n -alkane distribution and pristane/phytane ratio) and aromatic hydrocarbons (methyl phenanthrenes) with coal rank are observed.

The occurrence and distribution of polycyclic musks in the Lippe River system (a tributary of the Rhine River, Germany) was investigated in order to observe the dynamic transport and partitioning of these compounds between aqueous and particulate phases after their discharge into the river by sewage effluents. 1,3,4,6,7,8-Hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[g]-2-benzopyrane (HHCB), 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN), 6-acetyl-1,1,2,3,3,5-hexamethylindane (AHMI) and 4-acetyl-1,1-dimethyl-6-tert.-butylindane (ADBI) concentrations were determined in 19 water and surface sediment samples which were taken from a longitudinal section of the river. HHCB and AHTN were present in each of the water samples at concentrations ranging from < 10 to 180 ng 1 -1 and < 10 to 70 ng 1 -1 , respectively. The load of dissolved HHCB and AHTN was calculated on the basis of compound concentrations in water and the corresponding river runoff data and ranged from 3 to 293 g day -1 and from 1 to 108 g day -1 , respectively. Increasing loads of HHCB and AHTN along the river reflect a high input of sewage effluents to the densely populated areas along the central part of the river. Decreasing loads at the lower reaches indicate that in the corresponding river sections the rate of removal of musks was higher than the rate of input. Degradation and/or adsorption to particulate matter are processes that might explain this phenomenon. Consequently, high concentrations of HHCB and AHTN were detected in surface sediments from the Lippe River (from 5 to 191 μg kg -1 and from 2 to 1399 μg kg -1 , respectively). HHCB/AHTN ratios in sediment samples were lower (average 1.2) than in water samples (average 2.9), suggesting the preferential adsorption of AHTN to particulate matter.

GC/MS analyses have been applied to sediment samples of the German Bight in order to document the state of organic contamination as well as to identify specific molecular markers that are appropriate to estimate the discharge of anthropogenic compounds derived from the Elbe river. Detailed screening analyses revealed a wide variety of organic lipophilic compounds of biogenic, petrogenic as well as anthropogenic origin. Potential marker compounds indicating the contribution of the Elbe river could be attributed mainly to the chlorinated aromatic contaminants. Specifically, these include tetra- to hexachlorobenzenes, mono- to dichloronaphthalenes, hexachlorobutadiene, tetrabutyl tin, alkylsulfonic acid phenylesters, 1,2,3,6,7,8-hexahydro-1,1,6,6-tetramethyl-4-isopropyl- as -indacene and 4,4′-dichlorodiphenylsulfide. These compounds are suitable to indicate the spatial distribution of Elbe river derived organic matter.