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The chemical and isotopic compositions of gases from hydrocarbon systems of the Taranaki Basin of New Zealand (both offshore and onshore) show wide variation. The most striking difference between the western and south-eastern groups of gases is the helium content and its isotopic ratio. In the west, the Maui gas is over an order of magnitude higher in helium concentration (up to 190 μmol mol−1) and its 3He/4He ratio of 3.8 RA (where RA=the air 3He/4He ratio of 1.4×10−6) is approximately half that of upper mantle helium issuing from volcanic vents of the Taupo Volcanic Zone. In the SE, the Kupe South and most Kapuni natural gases have only a minor mantle helium input of 0.03–0.32 RA and low total helium concentrations of 10–19 μmol mol−1. The 3He/C ratio (where C represents the total carbon in the gas phase) of the samples measured including those from a recent study of on-shore Taranaki natural gases are generally high at locations where the surface heat flow is high. The 3He/CO2 ratio of the Maui gases of 5 to 18×10−9 is higher than the MORB value of 0.2 to 0.5×10−9, a feature found in other continental basins such as the Pannonian and Vienna basins and in many high helium wells in the USA. Extrapolation to zero CO2/3He and CO2/C indicates δ13C(CO2) values between −7 and −5‰ close to that of MORB CO2. The remaining CO2 would appear to be mostly organically-influenced with δ13C(CO2) c.−15‰. There is some evidence of marine carbonate CO2 in the gases from the New Plymouth field. The radiogenic 4He content (Herad) varies across the Taranaki Basin with the highest Herad/C ratios occurring in the Maui field. δ13C(CH4) becomes more enriched in 13C with increasing Herad and hydrocarbon maturity. Because 3He/4He is related to the ratio of mantle to radiogenic crustal helium and 3He/C is virtually constant in the Maui field, there is a correlation between RC/RA (where RC=air-corrected 3He/4He) and δ13C(CH4) in the Maui and New Plymouth fields, with the more negative δ13C(CH4) values corresponding to high 3He/4He ratios. A correlation between 3He/4He and δ13C(CO2) was also observed in the Maui field. In the fields adjacent to Mt Taranaki (2518 m andesitic volcano), correlations of some parameters, particularly CO2/CH4, C2H6/CH4 and δ13C(CH4), are present with increasing depth of the gas reservoir and with distance from the volcanic cone.

An Australian bituminous coal has been heated, both alone and in the presence of bentonite, from 200 to 360°C over a period of 4 days. The heating sequence was designed to simulate coalification in a subsiding basin in which volatiles are confined to the generating sequence. The clay particles act as centres for catalytic cracking of volatile matter which cannot then adsorb within the coal on cooling. Evidence for deposition of “carbon” within the clay comes from thermal analysis, light microscopy and transmission electron microscopy. GC-MS data show that polycyclic aromatic hydrocarbons are only present in the free oil that is generated during maturation when clay is available as a catalyst.

The flux and compositions of solvent-extractable lipid fractions were measured in particulate matter collected periodically by moored sediment traps in the Santa Monica Basin from 1985–1988. The purpose was to assess the compositional changes during settling, the carbon dynamics in the basin and to estimate the impacts of energy-related by-products on the surface sediments. Sediment traps recorded consistently high lipid fluxes in the eastern slope relative to the central basin, reflecting elevated terrigenous carbon inputs possibly from land-based human activities. Generally, lipid fluxes decrease offshore but increase vertically with water depth below ∼500m, implying lateral transport of particles. The steep decline of flux in the top 500m of the water is related to the rapid decomposition and mineralization of the marine-derived cellular carbon compounds. Less than 5% of the marine lipid components reach the seabed. In contrast, preferential preservation of terrigenous lipid is clearly evident from the chemistry of deeper traps and surface sediments. The lateral transport of particles is reflected in the presence of higher plant-derived lignin phenols and sewage-derived coprostanol and epicoprostanol in the deep trap material as well as in surface sediment throughout the basin. Petroleum triterpanes characteristic of natural seepage also permeates through the entire basin. Based on the data collected from both the trap particulte matter and surface sediments, a carbon budget for the Santa Monica Basin has been constructed.

Carbon cycling in coastal sediments was investigated using stable isotopes of carbon and nitrogen and radiocarbon isotope of various compound class fractions from a subsurface sediment section (30–50 cm) of Santa Monica Basin (SMB) and a composite of six surface grab sediments from McMurdo Sound, Antarctica. The range of stable isotope ratios reflects a mixture of terrestrial and marine inputs in the SMB sediments. By contrast, the uniformity of the carbon isotopic signature in the Antarctic sediments is characteristic of a dominantly planktonic contribution. Additional information on sources, particle processing and organic matter preservation was obtained by integrating the stable isotope data with radiocarbon measurements and molecular composition of the same fractions. Inputs of carbon from submarine seeps in coastal sediment are obvious from the relatively older age observed in the aliphatic and aromatic hydrocarbon fractions from the sediments of SMB. On the other hand, eroded sedimentary sequences containing coal could have imparted a non-recent age to the aliphatic and aromatic fractions in the Antarctic sediments. A major biogenic origin is evident from the younger age of most of the Antarctic sediment organic fractions compared to those from SMB. The humic and fulvic acid fractions from both the regions of investigation exhibit relatively young age in the range of 760–1700 BP. In contrast, protokerogen is much older (5470 and 8770 BP, respectively) than the humic and fulvic acids in both the sample locations. This suggests that protokerogen is more likely derived from the selective accumulation and preservation of refractory residues of biological organic components rather than being generated by in situ humiflcation. These results have important implications to the carbon cycling in coastal sediments and in understanding the formation of kerogen.

I.R. Kaplan, M.H. Alimi, Y. Galperin, L.P. Lee and S.T. Lu Abstract This presentation describes a set of chemical tests which have been developed to characterize hydrocarbon fuels released into the environment. The methods examine various homologous series of hydrocarbons including straight chain (paraffins or n-alkanes), branched chain (isoparaffins or isoprenoids), cyclic (naphthenes or alkylated cyclohexanes), polycyclic (steranes and terpanes) and aromatic structures (BTEX, alkylated benzenes, PAH and alkylated PAH compounds and aromatic steranes). Each one of these groups of hydrocarbons has a different tolerance to alteration (evaporation, water washing and biodegradation). When used as an analytical system on environmental samples, the data obtained provide information on fuel type recognition patterns and on degradation levels of the various fuels. Introduction It has been well established. with a large literature citation extending back over forty years. that crude oil in the environment is altered by a series of processes leading to tar balls and asphaltenic residues. These processes involve evaporation. water solution or water washing and biodegradation of various components. As a general rule, the low molecular weight hydrocarbons with the highest vapor pressure will escape from the crude oil rapidly. Next. in the presence of either standing water (ocean, lakes, rivers or aquifers) or rain, the soluble components begin to be removed. Benzene is the most soluble hydrocarbon (1750 ppm) followed by toluene (550 ppm) and other aromatic hydrocarbons. The light hydrocarbon gases such as methane and ethane are also among the most soluble hydrocarbons. Following the selective removal of the most volatile and most soluble components of a crude oil, the residual components can remain in a sterile environment for an indeterminate period of time. Crude oil has been produced from early Paleozoic reservoirs. more than 500 million years old and Precambrian source rocks approaching one billion years in age. such as the Weiyuan in the Sichuan Basin in China and sediments in McArthur River Area. Northern Territory, Australia. The two controlling parameters that regulate the decomposition rate of the hydrocarbons in crude oil are (1) temperature and (2) the presence or absence of oxygen. Although thermophilic bacteria that grow at temperatures between 90 - 100 C have been known for a long time, recent work by Stetter and his colleagues has shown that it is possible to grow bacteria at temperatures above 110 C at elevated pressures. Empirical observations, however. indicate that whereas in shallow crude oil reservoirs containing water. biodegradation of hydrocarbons occur, those more deeply buried with temperatures exceeding 82 C (the Pasteurization temperature) do not show evidence of significant biodegradation. P. 601

Dry natural gases produced from the Sacramento and northern San Joaquin basins contain up to 87% nitrogen. δ15N measurements for gases with N2 ≥ 8% vary from 0.9%. to 3.5%.; methane δ13C values vary from −61%. to −15%. 3 He 4 He ratios indicate the presence of mantle-derived helium in addition to radiogenic crustal helium and suggest that the gases may originate from mixing between three principal components: a hydrocarbon-rich gas with 3 He 4 He ≤ 0.1R A derived from the microbial and thermogenic alteration of sedimentary organic matter, a hydrocarbonrich gas with 3 He 4 He ≥ 2.75R A derived from the localized pyrolysis of sediments by magmatic volatiles, and a nitrogenrich gas with 3 He 4 He ≥ 1R A The nitrogen-rich component is characterized by methane δ13C less negative than −25%. and N 2 Ar ratios as high as 22,000. Nitrogen concentrations tend to increase towards the basement along the shallow eastern margin of the valley suggesting that the nitrogen-rich component is derived from metasedimentary rocks deep within the crust. The Coast Ranges Fraciscan complex, which was thrust well beneath the Great Valley during Late Mesozoic and Early Cenozoic subduction, appears to be the most likely source.

Latitudinal trends in plankton 13 C: 12 C significantly differ between northern and southern oceans. The results corroborate previous that (1) a strict temperature-plankton 13 C: 12 C relationship common to all oceans does not exist, and (2) geographic differences in plankton biosynthesis or metabolism are important in causing latitudinal variations in plankton carbon isotope abundance.

Hydrocarbons and inorganic gases have been analyzed in the drilling fluid of the Gravberg-1 well, Siljan Ring, Sweden, which represents the first commercial exploration for mantle-derived methane. Hydrocarbons detected to a depth of ∼6.6 km have been in trace amounts, dissolved in the drilling fluid. Low concentrations of hydrocarbons from granite intervals are rich in unsaturated hydrocarbons, and may result from abiogenic synthesis from inorganic carbon species in the granite, or may be synthesized, during drilling operations, from organic precursors in the drilling fluid. Below ∼5 km, higher hydrocarbon concentrations in granite intervals are correlated with two different lubricants added to the drilling fluid. These gases are characterized by distinctive suites of hydrocarbons, especially in the C4–C6 range. The effects of hydrocarbon production from these and other additives are particularly pronounced in this well, due to the low concentration of indigenous hydrocarbons. The highest concentrations of methane were enriched in 13C ( δ 13 C > −26‰ ), and were associated with several dolerite intrusions in the granite rocks. This methane was present in both a core and cuttings, and is similar to methane isolated from dolerite in a well recently drilled in Massachusetts, U.S.A. The methane may have a deep upper-mantle origin, or may be a product of abiogenic synthesis in crustal rocks. Significant quantities of H2 and He, occurring deeper than 6 km, appear to have a low-temperature crustal origin: there is no evidence of significant amounts of upper-mantle He in the Gravberg-1 gases.

In comparing a control vs. a sewage-affected nearshore site off southern California, the natural relative abundances of 13C, 15N and D in Dover sole and Ridgeback prawn muscle were found to be significantly different. This between-site shift in animal isotope abundance is of the type expected if sewage organic materials were an important food source for animals in the latter site. Use of stable isotope natural abundance to trace the incorporation and movement of sewage-derived organics in marine food webs is suggested.

Helium isotope ratios in Sacramento basin natural gas wells show a strong mantle signal. The3He/4He ratios range from 0.11 times the atmospheric ratio (0.11 RA) in the Rio Vista field to 2.75 RA in the Moon Bend field, indicating that 1% to 34% of the helium is mantle-derived. 3He/4He versus CH4/4He ratios provide evidence of two-component mixing between crustal and magmatic end-members. Extrapolation of the linear regression line to CH4/4He = 0 gives a hypothetical magmatic end-member 3He/4He ratio of 3.84 RA, half the typical mantle ratio. This indicates that the magmatic end-member may actually represent a mixture of mantle and crustal helium. Gases which deviate from the simple two-component mixture can be explained by addition of pure methane, radiogenic 4He, or a high N2-He component with 3He/4He = 0.6 Ra to 1.0 RA. The CH4/3He ratio of the magmatic end-member remains poorly constrained (0 to 3 × 109) and one cannot rule out the possibility that a significant proportion of the methane in some fields may be of deep-earth origin. However, fields with the highest 3He/4He ratios are associated with buried Plio-Pleistocene intrusives which have up-arched sediments to form hydrocarbon traps. The methane in these fields may have been produced by rapid thermal alteration of the intruded sediment. Elsewhere, the methane appears either to have migrated from deeply-buried sediments in the western basin or to have been produced by local microbial activity.

More than 28·1012 ft.3 (79·1010 m3) of natural gas and 5.3·109 bbl (8.4·108 m3) of oil have been produced in Kansas, U.S.A., from Paleozoic carbonate and sandstone reservoirs on structural uplifts and shallow embayments along the northern margin of the Anadarko basin. A heavily-explored, geologically well-characterized state, Kansas is an excellent place to study hydrocarbon migration and to test geochemical models for the origin of natural gases. Immature to marginally-mature rocks of eastern Kansas (Cherokee and Forest City basins) produce mixed microbial and thermogenic gases. Gases in this region have wetness = 0.03–51%, methane δ13C = −65 to −43‰ and methane δD = −260 to −150‰. Gases from central and western Kansas (Nemaha uplift to Hugoton embayment) are entirely thermogenic and have wetness =4–51%, methane δ13C = −48 to −39‰ and methane δD = −195 to −140‰. Ethane and propane δ13C-values throughout Kansas vary from −38 to −28‰ and from −35 to −24‰, respectively. Mature thermogenic gas (generated from source rocks in southwestern Kansas and the Anadarko basin with 1.0% ≤ Ro ≤ 1.4%) is recognized throughout the state. Lateral migration into shallow reservoirs on the Central Kansas and northern Nemaha uplifts and in the Cherokee basin probably occurred along basal Pennsylvanian conglomerates and weathered Lower Paleozoic carbonates at the regional sub-Pennsylvanian unconformity. Early thermogenic gas (generated by local source rocks with Ro ≤ 0.7%) is recognized in isolated fields in the Salina and Forest City basins, in Ordovician reservoirs beneath the sub-Pennsylvanian unconformity in the Cherokee basin, and in reservoirs generally above the unconformity in the Cherokee and Sedgwick basins, the eastern Central Kansas uplift and the Hugoton embayment.

Chemical and isotopic compositions have been measured on 62 microbial gases from Tertiary hemipelagic sediments in the Middle America Trench off Guatemala and from decaying kelp and surf grass currently accumulating in Scripps Submarine Canyon off southern California. Gases from the Middle America Trench have been generated primarily by the reduction of carbon dioxide; methane δ13C varies from −84‰ to −39‰, methane δD varies from −208‰ to −145‰, and carbon dioxide δ13 C varies from −27‰ to +28‰. Gases from Scripps Submarine Canyon have been generated primarily by acetate dissimilation; methane δ13 C varies from −63‰ to −43‰, methane δD varies from −331‰ to −280‰, and carbon dioxide δ13C varies from −17‰ to +3‰. Methane δ13C values as heavy as −40‰ appear to be uncommon for gases produced by carbon dioxide reduction and, in the Middle America Trench, are associated with unusually positive carbon dioxide δ13C values. However, based on the 25‰ intramolecular fractionation between acetate car☐yl carbon and methyl carbon estimated from the Scripps Submarine Canyon data, methane produced by acetate dissimilation may commonly have heavy δ13C values. The δD of methane derived from acetate is more negative than natural methanes from other origins. Microbial methane δD values appear to be controlled primarily by interstitial water δD and by the relative proportions of methane derived from carbon dioxide and acetate. The chemical and isotopic compositions of microbial gas and thermogenic gas overlap, making it difficult to determine the origins of many commercial natural gases from methane δ13C and C2+ hydrocarbon concentrations alone. Measurements of methane δD and carbon dioxide δ13C can provide useful additional information, and together with ethane δ13C data, help identify gases with mixed microbial and thermogenic origins.

L'echantillonnage porte sur une large collection d'invertebres, poissons et mammiferes des eaux cotieres du sud de la Californie et des eaux pelagiques entre Costa Rica et l'ile Cocos. Mise en evidence d'un leger mais progressif accroissement du 13 C/ 12 C dans les tissus des animaux (muscle) lorsque croit le niveau trophique. Interet de ces resultats dans l'etude des biocenoses

He isotope ratios provide important constraints on the input of magmatic gases into crustal systems. Natural gas associated with active continental margins from Taiwan (R.O.C.), New Zealand, the Philippines, Indonesia, Thailand and Alaska (U.S.A.) contain a magmatic He component, based on measured 3 He 4 He ratios (R) ranging from 0.5 to 3.8 times the atmospheric value (RA). The methane-helium results can be interpreted as the result of a mixture between a low - 3 He 4 He (0.01R A ) , high-CH 4 3 He crustal end-member and a high - 3 He 4 He (0.6-3.9R A ) , low -( CH 4 3 He 6 ) magmatic component. The presence of mantle He does not require significant amounts of mantle methane. A better fit to the data is obtained using a “zero-methane” magmatic end-member. The worldwide association of 3He and magmatic activity suggests that volcanism plays a role in methane generation by supplying the heat needed to convert organic matter to methane thermogenically. Only gases from the accretionary prism of Barbados (West Indies) appear totally devoid of magmatic He ( 3 He 4 He ratio=0.02RA); the He is completely of crustal origin. There is no evidence that faults within the accretionary prism of this fore-arc act as conduits for the migration of mantle He. Many of the gases studied contain significant quantities of CO2 which appear to result from two processes. 3 He 4 He , high-CO 2 3 He gases (0.01RA, 1011) possibly result from decarbonation reactions in the crust, while the high - 3 He 4 He , low-CO 2 3 He gases (2−4RA

Natural oil seepage contributes approximately 10% (0.6 × 106 metric tons per year) of the annual input of petroleum hydrocarbons to the marine environment and half of that arises from the continental shelves of the circum-Pacific. Chemical properties of submarine petroleum seeps are reviewed, focusing on those of the Southern California Borderland, in relation to crude oil produced in the same geographic area, the compositional changes due to weathering in the marine environment, and the hydrocarbon and trace element compositions of the surrounding seawater and adjacent sediments. One purpose has been to determine whether the hydrocarbon compositions of seawater or surface sediments reflect the composition of nearby seepage, and can be used to identify previously unknown petroleum sources. The analytical procedures included identification of saturated hydrocarbons by gas chromatography and gas chromatography/mass spectrometry; stable isotopic ratios of sulfur, nitrogen and carbon on gas and oil, and the δ13C for various liquid-solid chromato-graphic fractions. The range in δ34S covered by the California oils is −4 to +15.9%., and the δ15N range is from +5.6 to +11%.. Carbon isotopic ratios for total oils exhibit a relatively narrow range (−22.1 to −27.3%.); however, chemical fractions show a relatively greater variation (−21.5 to −31.5%.), with the hexane fraction lighter than the total oil, and the n-alkanes representing the lightest of all fractions measured. The content of nitrogen and sulfur, their isotopic ratios, and the δ13C of chromatographic fractions, serve to distinguish oils and seeps derived from different formations. Comparison of gas chromatographic/mass spectrometric data from a seep and from a crude oil produced nearby show cycloalkane compositional differences attributable to origins, rather than to differences in weathering history. Data presented demonstrate that analyses of the water column for enrichment in high-molecular-weight hydrocarbons or trace metals adjacent to seep areas may produce equivocal results. Sediment analysis appears to give a more reliable indication of petroleum contribution. Anthropogenic hydrocarbons and trace metals, derived from shipping lanes, harbor activities, or sewage disposal systems, can exceed natural concentrations and thereby alter the distribution pattern. However, marine sediments receiving petroleum contributions can be differentiated from those in which only biogenic hydrocarbons are present.

Twenty meteorites were studied in the iron (hexahedrites and octahedrites) and stony (enstatite achondrite, carbonaceous, enstatite, bronzite and hypersthene chondrites) families. Troilite is the chief sulfur component of iron meteorites and the δS34 ranges from 0 to + 0.6‰ with respect to Canyon Diablo troilite. Stony meteorites contain a wide variety of sulfur compounds including water and acid soluble sulfides, elemental sulfur, water and acid soluble sulfates and unidentified components soluble only in aqua regia. The δS34 content of the isolated compounds varies from +2.5 to −5.5‰ with respect to Canyon Diablo. The weighted average for all components of each meteorite, however, falls within ± 1 ‰ of Canyon Diablo. The S33 distribution closely follows S34. The data strongly suggest that differentiations have occurred in a closed system, corresponding to the meteorites or their parent body, and starting from a single source of sulfur. There is no evidence for biological activity having occurred in the meteorites, either from the distribution of sulfur compounds or from the isotope abundance data.

Analyses of sulphur compounds in basin sediments off southern California indicate that elemental sulphur, free sulphide, hydrotroilite, organic sulphur, sulphate and pyrite are present in quantities that vary with environment and depth in the sediments. Pyrite is generally the most abundant form, occurring in oxidizing as well as in reducing sediments and often constituting 90 per cent of total sulphur. A material balance indicates that the total sulphur content is far in excess of the sulphate-sulphur initially trapped in the interstitial water. This evidence, together with failure to detect significant alternate sources, suggests that sulphate-sulphur is extracted from the overlying sea water at the sediment-water interface. Isotope measurements confirm many of the conclusions suggested by the quantitative chemical analyses. They show that biological sulphate reduction is the single most important process in the sulphur cycle. The sulphide released is converted to hydrotroilite and then to pyrite. Elemental and organic sulphur appear to be continually forming and reacting in the sediment column. The organic sulphur released from decaying organic matter apparently plays only a small role in the sulphur economy. Enrichment in S32 ranging from 9 to 62‰ was measured in pyrite fragments, a spread similar to that previously observed in ancient sediments. Data from field and laboratory experiments were combined to determine rate of sulphate reduction, number of sulphate reducing bacteria and the amount of organic matter decomposed during sulphate reduction in the sediment, as well as rate of renewal of water in the basins. The results suggest that the methods used may have many applications for elucidating in situ rate processes.

In situ measurements by calcite and aragonite saturometry in the intermediate waters of the northeastern Pacific, indicate that these waters are close to saturation with respect to calcite. It is proposed that the carbonate compensation depth in this region is mainly controlled by the degree of carbonate saturation of ocean waters. If this suggestion is correct, then the carbonate compensation depth can be shown to be directly related to the alkalinity and nutrient cycles in the oceans. Three independent factors seem to control the depth of carbonate compensation: bottom topography, nutrient recycling rate (oceanic mixing) and a dependency factor relating biogenic CaCO 3 production to nutrient availability.

Methods based on paper and cellulose column chromatography are described for the rapid separation of small quantities of bacteriochlorophyll and Chlorobium chlorophyll. Spectral absorption curves are given as evidence of the efficiency of the methods to separate pure products. Curves are given for bacteriochlorophyll in ethyl ether and in ethanol. It was found that bacteriochlorophyll could be stored at −10 ° without much deterioration, but it was necessary to saturate the solvents with H 2 S to prevent decomposition of the chlorophyll during purification. Chlorobium chlorophyll has very different chromatographic properties from chlorophyll a, but similar spectroscopic properties. The chlorophyll in the purple sulfur bacteria and that in the green sulfur bacteria were shown to be different pigments.

Reducing surface sediment from a depth of 300 m in the Dead Sea was found to contain phytanic acid (520 μg/Kg), dihydrogen phytol (800 μg/Kg) and phytane (17 μg/Kg). An investigation revealed that glycerol phytanyldiether could be isolated from the sediment by hydrolysis of a lipid soluble fraction. The phytanyldiether is probably derived from the phosphatidyl glycerophosphate lipid, which has been demonstrated by Kates and co-workers to be the dominant lipid present in red halophilic bacteria. Comparison of results by analysis of Halobacterium cutirubrum, using the same analytical procedure as was used for the sediment investigation, confirmed the authenticity of the lipid characterization. In view of this finding, it is suggested that phytane in the Dead Sea sediment has been derived from this lipid and that long-chain isoprenoid hydrocarbons in some ancient environments may have had a similar origin.

Studies were performed to determine the distribution of microbiota in the Dead Sea during 1963 to 1965. The dominant organisms in the surface water were found to be two red halophilic bacteria, followed in abundance by a green flagellated alga, Dunaliella virdis. Cultures inoculated with Dead Sea water produced growth of the red bacteria as well as unidentified non-pigmented halo-tolerant bacteria, capable of growing in 25% salt solution, and bacteria that grew only in dilute salt media. The latter are mainly spore-forming aerobes, probably introduced by rain-wash of the soil, as well as from the Jordan River and fresh water springs. Sulfate reducing bacteria were also cultured from the water and from the sediment. Pigment studies on extracts from laboratory cultures of the red bacteria, from centrifuged suspensions of Dead Sea water and, by comparison, from a pure culture of Halobacterium salinarium, showed that the dominant pigment in all cases was the carotene α-bacteriorubrin. The total number of organisms decreased with depth of the water column, especially below the thermocline. The interpretations given for the decrease are: lack of dissolved oxygen, decrease in incident light, and lack of dissolved phosphate. The last factor is probably due to rapid precipitation of phosphate by divalent ions.

Eight carbonaceous chondrites (Orgueil, Cold Bokkeveld, Mighei, Murray, Felix, Lance and Warrenton), five non-carbonaceous chondrites (Richardton, Bjurbole, Karoonda, Abee and Hvittis) and one achondrite (Norton County) were examined for organic constituents. Hydrocarbon-type organic matter was extracted from the samples with organic solvents (benzene-acetone and acetone-methanol) and studied by ultra-violet, visible and infra-red absorption spectroscopy and by nuclear magnetic resonance spectroscopy. Both aliphatic and aromatic compounds were detected; in addition carbonyl groups appeared to be present as well as unsaturated groups of the vinyl or allylic type. The extractions also separated elemental sulfur in Orgueil, Cold Bokkeveld, Mighei and Richardton. Amino acids and sugars were encountered in all the meteorites studied. The sugars were present in small quantities (5–26 μ g/g) with mannose and glucose the most abundant. Amino acids were present in greater concentrations—30–500 μ g/g in the carbonaceous chondrites and 8–50 μ g/g in the others. Seventeen amino acids were detected: serine, glycine, alanine, the leucines. glutamic acid, asparatic acid and threonine were found to be the most abundant. C'hondrules were isolated from Mokoia, Bjurbole and Richardton, and analysed for sugars and amino acids. Those from Mokoia and Bjurbole were carefully washed before analysed. No sugars were present and glycine was the only water-soluble amino acid found. Besides glycine a great variety of ninhydrin-positive compounds appeared on the chromatograms. In the acid hydrolyzate, alanine, serine, threonine, the leucines, glutamic acid and aspartic acid were also present. Acid hydrolyzates of carbonaceous chondrites contained 16 diazonium-sensitive compounds, four of which had the Chromatographic properties (in terms of Rf value and color) of hydroxy-berizoic, p-hydroxybenzoic, p-hydroxyphenylacetic, and vanillic acids. In addition, fifteen unidentified, ultraviolet-absorbing and fluorescing compounds appeared on the chromatogram. All extracts were tested for optical rotation on a polarimeter capable of measuring 0.0005°. No rotation could be detected. The absence of rotation, the type and distribution pattern of amino compounds in chondrules and matrix, the lack of pigments, fatty acids and presumably nucleic acids in addition to other biochemical criteria, suggest that the organic material has been synthesized by chemical rather than known biochemical processes.

The principal objective of the current on-going project is to understand the processes involved in the cycling of organic carbon in the southern California Bight. This involves the evaluation of the relative flux of planktonic carbon to the seafloor versus the import of terrestrial carbon components and the determination of the rate of decomposition of sedimenting organic matter in the water column. These goals were achieved by the chemical characterization of sedimenting particles (from traps) as well as in the near surface sediments. The organic matter in the marine regime comprises contribution from land plants, marine productivity (plankton and bacteria) as well as anthropogenic sources. At UCLA, we have been focusing on the chemical characterization of selected classes of organic carbon compounds derived from these various sources to understand the vertical flux and the chemical composition of the particulate organic matter which are controlled by complex transport, transformation, degradation and remineralization processes.

An exploratory study was made of the Battelle Megavolume Sampler. This device collects gram quantities of aerosol particles from air at high flow rates, by impaction and electrostatic precipitation, in three ranges of particle size, namely 0-1.7 ..mu..m, 1.7-3.5 ..mu..m, and >3.5 ..mu..m. The usefulness of various sample treatments and analyses were examined. Samples were taken at the foothill location northeast of Los Angeles, where intense photochemical smog is often encountered. Samples were extracted into organic or aqueous solvents for chromatographic and spectroscopic treatments. Individual components were identified in the following classes: alkanes, fatty acids, dicarboxylic acids, carbonyl compounds, polynuclear aromatic hydrocarbons, inorganic anions, and metals. Elemental analyses for C, H, and N, /sup 13/C//sup 12/C ratios, electron spin resonance, and /sup 14/C radio-activities were also run. The sampler was simple to operate and gave suitable samples, but quantitative recovery of material from the sampler was difficult. The distribution of certain homologous series of organic compounds, the high electron spin densities, and the finding from /sup 14/C activities that only about 50% of the noncarbonate aerosol was fossil, all indicated that a substantial part of the aerosol was biogenic.

Two methods were developed for the separation of plastid pigments by paper chromatography: (a) One is based on the reversed phase procedure and uses Whatman No. 4 paper impregnated with paraffin oil, and methanol as the irrigation solvent; (b) the second is an improvement on existing methods, and consists in the use of the circular procedure on unimpregnated paper to repress tailing. Cellulose columns were also successfully used. By a combination of these methods it is possible to identify and separate in a state of spectroscopic purity the natural chlorophylls and some of the carotenoids. Conditions to avoid deterioration of the sensitive pigments during irrigation and elution are briefly discussed.