Chemical Variation from Biolipids to Sedimentary Organic Matter in Modern Oceans and Its Implication to the Geobiological Evaluation of Hydrocarbon Source Rocks
-
摘要: 现代海洋生物有机组分的动态变化过程是利用正演法评价海相优质烃源岩的重要中间环节, 可以为估算沉积过程中有机质的损耗提供参考.从化学组成来看, 生物体的脂类与原油成分最为接近, 而且与其他生化组分相比, 脂类的化学性质相对稳定, 可以长期保存在地层中, 因此脂类是最重要的生油母质.温度、盐度、CO2等环境条件以及生物的种类和生长阶段对生物脂类组成有重要影响, 不同环境条件和不同种类的生物对烃源岩有机质的贡献也不同.海水中的有机质在沉积过程中受原始生产力和氧化还原条件的影响.在特定生境中, 在一定的生产力范围内, 沉积有机质的通量与生产力有正相关关系.超过此范围, 沉积有机质通量与生产力关系不大.氧化条件下有机质降解速度快, 而还原条件则有利于沉积有机质的保存.生物膜的形成不仅使有机质更容易沉积, 而且降低了有机质被降解的机会.地质历史时期生物膜的识别对研究烃源岩有机质的保存具有重要意义.Abstract: Understanding the dynamics of organic matter in marine water columns greatly favors the geobiologcal evaluation of hydrocarbon source rocks. Biolipids could make great contribution to petroleum due to their comparable chemical components and the slightly refractory characteristics of biolipids during the microbial/thermal degradation. A variety of environmental factors such as temperature, CO2 and salinity could affect the biochemical contents in microorganisms. As a result, microorganisms living in a changing environmental condition might have a different contribution to petroleum formation. Organic carbon flux shows a positive correlation with biological productivity only within a certain range of biomass volumes in a specific biohabitat. Furthermore, organic matter is degraded much more quickly in a water column with oxic conditions. Therefore the anoxic condition, along with the enhanced biological productivity, would be one of the significant factors in contributing the formation of high-quality hydrocarbon source rocks. The formation of biofilms favors the preservation of sedimentary organics by enhancing the deposition rate and decreasing the degradation rate of organics. Identification of biofilms in sedimentary rocks will thus greatly help to understand the depositional processes of organic matter finally preserved in hydrocarbon source rocks.
-
Key words:
- modern oceans /
- primary productivity /
- biochemicals /
- biofilm /
- sedimentary organic matter /
- hydrocarbon source rocks
-
图 1 非极地区海洋2 000 m深处年生产力与有机碳通量的关系(据Harvey, 2006修改)
Fig. 1. The relationship between annual organic carbon flux and annual primary productivity at 2 000 m depth of non-polar marine (Modified from Harvey, 2006)
图 2 海洋生物生化组分的降解(据Harvey, 2006,重新绘制)
Fig. 2. Variations of biochemicals in marine organisms during degradation (Redrew from Harvey, 2006)
表 1 生物体及其演化产物的平均元素组成(据王启军和陈建渝, 1984; 黄第藩和李晋超, 1982,综合)
Table 1. Mean contents of elements in organisms and their derived products
-
Araújo, S. C., Garcia, V. M. T., 2005. Growth and biochemi-cal composition of the diatom Chaetoceros cf. wighamii brightwell under different temperature, salinity and car-bon dioxide levels: I. Protein, carbohydrates and lipids. Aquaculture, 246 (1-4): 405-412. https://www.cnki.com.cn/Article/CJFDTOTAL-SCYZ202103003.htm Berner, P. A., 1994. Geocarb Ⅱ: A revised model of atmos-pheric CO2 over Phanerozoic time. American Journal of Science, 294: 56-91. doi: 10.2475/ajs.294.1.56 Burdige, D. J., 2005. Burial of terrestrial organic matter in marine sediments: Are-assessment. Global Biogeochem-ical Cycles, 19 (4): GB4011. [47] Costerton, J. W., Marriet, J., Cheng, K. J., 1985. Phenomena of bacterial adhesion. In: Savage, D., Fletcher, M., eds., Bacterial adhesion. Plenum Press, New York, 344. [49] Egan, B., 1987. Marine microbial adhesion and its conse-quences. In: Sleigh, M. A., ed., Microbes in the sea. El-lis Horwood, 220-238. [51] Fletcher, M., 1985. Effect of solid surfaces on the activity of attached bacteria. In: Savage, D., Fletcher, M., eds., Bacterial adhesion. Plenum Press, New York, 339-362. Goňi, M. A., Nelson, B., Blanchette, R. A., et al., 1993. Fungal degradation of wood lignins: Geochemical per-spectives from CuO-derived phenolic dimmers and mon-omers. Geochimicaet Cosmochimica Acta, 57 (16): 3985-4002. https://www.cnki.com.cn/Article/CJFDTOTAL-CYXB201403002.htm Gordon, E. S., Goňi, M. A., 2003. Sources and distribution of terrigenous organic matter delivered by the Atchafalaya River to sediments in the northern Gulf of Mexico. Geochimicaet Cosmochimica Acta, 67 (13): 2359-2375. https://www.cnki.com.cn/Article/CJFDTOTAL-HJXX201602001.htm Gordon, E. S., Goňi, M. A., 2004. Controls on the distribu-tion of and accumulation of terrigenous organic matter in sediments from the Mississippi and Atchafalaya River margins. Marine Chemistry, 92: 231-352. https://www.cnki.com.cn/Article/CJFDTOTAL-HJHX202011027.htm Gough, M. A., Fauzi, R., Mantoura, C., et al., 1993. Terres-trial plant biopolymers in marine sediments. Geochimicaet Cosmochimica Acta, 57 (16): 945-964. [61] Harvey, H. R., 2006. Sources and cycling of organic matter in the marine water column. In: Volkman, J., ed., Ma-rine organic matter. Springer-Verlag, Berlin Heidelberg, 1-25. Harvey, H. R., Macko, S. A., 1997. Kinetics of phytoplank-ton decay during simulated sedimentation: Changes in lipids under oxic and anoxic conditions. Organic Geo-chemistry, 27 (3-4): 129-140. doi: 10.1016/S0146-6380(97)00077-6 Harvey, H. R., Tuttle, J. H., Bell, J. T., 1995. Kinetics of phytoplankton decay during simulated sedimentation: Changes in biochemical composition and microbial activ-ity under oxic and anoxic conditions. Geochimicaet Cos-mochimica Acta, 59 (16): 3367-3377. doi: 10.1016/0016-7037(95)00217-N Hartgers, W. A., Sinninghe, D. J. S., Requejo, A. G., et al., 1994. Evidence for only minor contributions from bacte-ria to sedimentary organic carbon. Nature, 369 (64-77): 224-227. Hartnett, H. E., Keil, R. G., Hedges, J. I., et al., 1998. In-fluence of oxygen exposure time on organic carbon pres-ervation in continental margin sediments. Nature, 391 (6667): 572-574. doi: 10.1038/35351 Hedges, J. I., Keil, R. G., 1995. Sedimentary organic matter preservation: An assessment and speculative synthesis. Marine Chemistry, 49 (2-3): 81-115. doi: 10.1016/0304-4203(95)00008-F Huang, D. P., Li, J. C., 1982. Formation of terrestrial petro-leum in China. Petroleum Industry Press, Beijing (inChinese with English abstract). [75] Huc, A. Y., Van Buchem, F. S. P., Colleta, B., 2005. Strati-graphic control on source rock distribution: First andsecond order scale. In: Harris, N. B., ed., The deposi-tion of organic carbon rich sediments: Models, mecha-nisms and consequences. SEPM (Society for Sedimen-tary Geology) Special publication, Tulsa, Oklahoma, 82: 225-242. Keil, R. G., Tsamakis, E., Fuh, C. B., et al., 1994. Minera-logical and textural controls on the organic composition of coastal marine sediments: Hydrodynamic separationusing SPLITT-fractionation. Geochimicaet Cosmochim-ica Acta, 58 (2): 879-893. doi: 10.1016/0016-7037(94)90512-6 Koki, H., Grant, W. D., 1998. Extremophiles, microbial lifein extreme environments. Wiley-Liss, New York. Krumbein, W. E., Stahl, L. J., 1991. The geophysiology of marine cyanobacterial mats and biofilms. Kieler Meeresforsch, 62: 158-163. Liang, Y., Mai, K. S., Sun, S. C., 2002. Effects of harveststage on the total lipid and fatty acid composition of four cylindrotheca strains. Chinese Journal of Oceanol-ogy and Limnology, 20 (2): 157-161. doi: 10.1007/BF02849653 Mayer, L. M., 1994. Surface area control of organic carbon accumulation in continental shelf sediments. Geochimicaet Cosmochimica Acta, 58 (4): 1271-1284. doi: 10.1016/0016-7037(94)90381-6 Nguyen, R. T., Harvey, H. R., 1997. Protein and amino acid cycling during phytoplankton decomposition in oxic and anoxic waters. Organic Geochemistry, 27 (3-4): 115-128. doi: 10.1016/S0146-6380(97)00076-4 Ourisson, G., Albrecht, P., Rohmer, M., 1984. The microbi-al origin of fossil fuels. Scientific American, 251 (2): 44-51. doi: 10.1038/scientificamerican0884-44 [91] Paerl, W., 1985. Influence of attachment on microbial metab-olismand growth in aquatic ecosystems. In: Savage, D., Fletcher, M., eds., Bacterial adhesion. Plenum Press, New York, 363-400. Prahl, F. G., Ertel, J. R., Goni, M. A., et al., 1994. Terres-trial organic carbon contributions to sediments on the Washington margin. Geochimicaet Cosmochimica Acta, 58 (14): 3035-3048. doi: 10.1016/0016-7037(94)90177-5 Ransom, B., Kim, D., Kastner, M., et al., 1998. Organicmatter preservation on continental slopes: Importance of mineralogy and surface area. Geochimicaet Cosmochim-ica Acta, 62 (8): 1329-1345. doi: 10.1016/S0016-7037(98)00050-7 [97] Stotzky, G., 1985. Mechanisms of adhesion to clays, with refer-ence to soil systems. In: Savage, D., Fletcher, M., eds., Bacterial adhesion. Plenum Press, New York, 195-254. [99] Summons, R. E., 1993. Biochemical cycles: A review of fun-damental aspects of organic matter formation, preserva-tion and composition. In: Engel, M. H., Macko, S. A., eds., Organic geochemistry: Principles and applications. Plenum Press, New York, 3-21. Tissot, B. P., Welte, D. H., 1978. Petroleum formation and occurrence. First Ed. . Springer verlag, Berlin. Tyson, R. V., 1995. Sedimentary organic matter-organic faci-es and palynofacies. Chapman & Hall, London. Wang, Q. J., Chen, J. Y., 1988. Geochemistry of petroleum and gas. China University of Geosciences Press, Wuhan (in Chinese). Westall, F., Rince, Y., 1994. Bioflims, microbial mats and microbe-particle interactions: Electron microscope ob-servation from diatomaceous sediments. Sedimetology, 41 (1): 147-162. doi: 10.1111/j.1365-3091.1994.tb01396.x Xia, J. R., Gao, K. S., 2005. I mpacts of elevated CO2 concen-tration on biochemical composition, carbonic anhydrase, and nitrate reductase activity of freshwater green algae. Journal of Integrative Plant Biology, 47 (6): 668-675. doi: 10.1111/j.1744-7909.2005.00114.x Zhu, L. Y., Zhang, X. C., Ji, L., et al., 2007. Changes of lipidcontent and fatty acid composition of Schizochytrium limacinum in response to different temperatures and sa-linities. Process Biochemistry, 42 (2): 210-214. doi: 10.1016/j.procbio.2006.08.002 黄第藩, 李晋超, 1982. 中国陆相油气生成. 北京: 石油工业出版社. 王启军, 陈建渝, 1988. 油气地球化学. 武汉: 中国地质大学出版社.