New findings about the Lake Salda Microbialites and Their Astrogeological Significance (Burdur, SW-Türkiye)

Öz

In Lake Salda (Southwestern, Türkiye), modern microbialites containing hydrated Mg carbonates continue to form on the shoreline of the lake and at 15 m water depth in structures ranging from a few cm in size to about 10 m in height with 3-4 m width. For the first time, these organo-sedimentary structures were classified and their morphotypes, sedimentological and textural characteristics along with their spatial distribution in the lake were identified. In this context, 5 different zones were identified in the lake. In the lake, stromatolitic thrombolites are the most dominant microbialite type, while stromatolites and thrombolites are restricted to certain parts of the lake. Stromatolitic thrombolites have a wide variety of morphologies, usually dome-shaped and cauliflower-like, while they are rarely tabular. On a meso-scale (cm), stromatolitic thrombolites exhibit finger-shaped (2-5 cm) laminated mini-columns, and dendritic, and bulbous growth structures. Thrombolites with cauliflower morphology coalesce to form a large reef-like structure at depth (10-20 m). Thrombolites with stromatolitic laminae and dendritic internal structure are limited to certain zones in the lake (Zone 2, 3). The macro-scale external morphology of the microbialites is shaped primarily by the influence of the prevailing environmental conditions. Seasonal fluctuations in lake water level, regional differences in sedimentation rates, prevailing winds and currents are the main factors controlling the depositional environment. The internal growth structure of microbialites depends on the microbial community structure and the conditions of the depositional environment. Mineralogical study of the microbial layer revealed a different hydrated Mg carbonate mineral, dypingite (Mg5(CO3)4. OH2.5H2O), for the first time. This mineral, closely related to extracellular polymeric matter (EPS), is the precursor of hydromagnesite. Petrographic investigations of the microbialites revealed the presence of abundant vertical and near-vertical filament (mineralised?)-like structures associated with carbonates, exhibiting a clotted texture containing peloids of various sizes in addition to a thin lamination. Nodular aragonites are generally associated with microbial layers, while fibres developed in voids and aragonite fans and isopach fringes formed by their aggregation indicate secondary and abiotic carbonate precipitation in the lake. Due to their structural, mineralogical and compositional diversity, Lake Salda microbialites are a potential modern analogue that may reveal the origin and formation processes of both Mg-carbonates in the geological record and hydrated Mg-carbonates detected in a possible palaeolake in Jezero crater, one of the Martian craters. In this study, new data on Lake Salda microbialites is evaluated in terms of their origin, formation mechanism and potential for biosignatures.

Anahtar Kelimeler

• Lake Salda
• Mars
• Biosignature
• Dypingite
• hydrated magnesium carbonates
• SW Türkiye

Salda Gölü Mikrobiyalitlerine Dair Yeni Bulgular ve Astrojeolojik Önemleri (Burdur, GB-Türkiye) / New findings about the Lake Salda Microbialites and Their Astrogeological Significance (Burdur, SW-Türkiye)

Öz

Salda Gölü’nde (Güney Batı Anadolu) sulu magnezyum karbonat (SMK) içerikli güncel mikrobiyalitler, kıyı şeridi boyunca ve 15 m su derinliğine kadar uzanan, birkaç cm büyüklüğünden yaklaşık 10 m yüksekliğe ve 3-4 m genişliğe kadar varan e yapılar şeklinde oluşmaya devam etmektedir. Sunulan çalışma kapsamında, ilk defa bu organo-sedimanter yapıların, morfotipleri, sedimentolojik ve dokusal özellikleri ortaya konulmuş; türlerine göre sınıflandırılmış ve göldeki mekansal dağılımları haritalanmıştır. Bu kapsamda gölün litoral kısmında 5 farklı mikrobiyalit zonu belirlenmiştir. Göldeki, stromatolitik-trombolitler en baskın mikrobiyalit türüdür ve gölün belirli kısımlarında tayin edilmişlerdir. Stromatolitik-trombolitler, genellikle kubbemsi ve karnabahar; nadiren tabular (yassı) olmak üzere çok çeşitli makro morfolojiye sahiptir. Orta ölçekte (cm), stromatolitik-trombolitler parmak şekilli (2-5 cm) laminalı mini sütunlar, yumru şekilli dendritik ve soğanımsı büyüme yapıları sergiler. Karnabahar morfolojisine sahip trombolitler birleşerek derinlerde (10-20 m) resif benzeri geniş bir yapı oluşturmaktadırlar. Stromatolitik ve dendritik iç yapılı mikrobiyalitler gölün belirli zonları ile sınırlıdır (Zon 2, 3). Mikrobiyalitlerin, makro boyuttaki dış morfolojisi, öncelikle hakim çevresel koşulların etkisi altında şekillenmektedir. Gölün su seviyesindeki mevsimsel dalgalanmalar, sedimantasyon oranlarındaki bölgesel farklılıklar, hakim rüzgar ve akıntılar depolanma ortamını kontrol eden başlıca faktörlerdir. Mikrobiyalitlerin iç büyüme yapısı, mikrobiyal topluluk yapısı ile çökelme ortamının koşullarına bağlıdır. Mikrobiyal tabakada yapılan mineralojik çalışma ile, ilk defa hücre dışı polimerik madde (HPM) ile yakından ilişkili farklı bir SMK minerali olan dipinjit minerali (Mg5(CO3)4.OH2.5H2O) tespit edilmiştir. Mikrobiyalitlerin petrografik incelemeleri, karbonatlar içinde bol miktarda dikey ve dikeye yakın konuma sahip filament (mineralize?) benzeri yapıların varlığını ortaya koymuştur. Nodüler aragonitler genellikle mikrobiyal tabakalarla ilişkili iken, boşluklarda gelişen lifler ve bunların bir araya gelmesi ile oluşan aragonit yelpazeleri, izopak saçaklar göldeki ikincil ve abiyotik karbonat çökelmesine işaret etmektedir. Morfolojik, mineralojik ve dokusal çeşitlilikleri nedeniyle Salda Gölü mikrobiyalitleri hem jeolojik kayıtlardaki Mg-karbonatların hem de Mars kraterlerinden biri olan Jezero Krateri’ndeki paleogölde tespit edilen SMK’ların kökeni ve oluşum süreçlerini ortaya koymak için potansiyel modern bir analogdur. Bu çalışmada, Salda Gölü mikrobiyalitlerinin kökenleri, oluşum mekanizmaları ve biyoiz koruma potansiyeli elde edilen yeni veriler ışığında, değerlendirilmiştir.

Anahtar Kelimeler

• Salda Gölü
• Mars
• Dipinjit
• Biyoiz
• GB-Türkiye
• Sulu magnezyum karbonat

Kaynakça

1. Allwood, A. C, Walter, M. R., Kamber, B. S., Marshall, C. P. & Burch, I. W. (2006) Stromatolite reef from the Early Archaean era of Australia. Nature, 441, 714–718. https://doi.org/10.1038/nature04764
2. Aloisi, G. (2008). The calcium carbonate saturation state in cyanobacterial mats throughout Earth’s history. Geochimica et Cosmochimica Acta, 72(24), 6037–6060. https://doi.org/10.1016/j.gca.2008.10.007
3. Andersen, D.T., Sumner, D.Y., Hawes, I., Webster-Brown, J. & McKay, C.P. (2011). Discovery of large conical stromatolites in Lake Untersee, Antarctica. Geobiology, 9, 280–293. https://doi.org/10.1111/j.1472-4669.2011.00279.x
4. Arp, G., Reimer, A. & Reitner, J. (2001). Photosynthesis induced biofilm calcification and calcium concentrations in Phanerozoic oceans. Science, 292, 1701–1704.
5. Arp, G., Reimer, A. & Reitner, J. (2003). Microbialite formation in seawater of increased alkalinity, Satonda Crater Lake, Indonesia. Journal of Sedimentary Research 73, 105–127. https://doi.org/10.1306/071002730105
6. Awramik, S. M. & Buchheim, H. P. (2009). A giant, Late Archean lake system: The Meentheena Member (Tumbiana Formation, Fortescue Group), Western Australia. Precambrian Research, 174, 215–240. https://doi.org/10.1016/j.precamres.2009.07.005
7. Awramik, S. M. & Margulhis, L. (1974) Definition of stromatolite, In E. Walter (Ed.), Stromatolite Newsletter, 2(5).
8. Balcı, N. (2022) Mars Yolculuğunda Yeni Keşifler ve Biyoiz Bulmacası. Herkese Bilim ve Teknoloji Dergisi, 324.

9. Balcı, N. ve Demirel, C. (2018). Salda Gölü’nün jeomikrobiyolojisi ve güncel stromatolit oluşumunda mikrobiyal etkiler. Hacettepe Üniversitesi, Yerbilimleri Uygulama ve Araştırma Merkezi Yerbilimleri Bülteni, 39(1), 19-40. 2018.
10. Balcı, N. & Güneş, Y. (2025). Tracking organomineralization from modern microbial layers of Lake Salda (hazırlık aşamasında).
11. Balcı, N., Güneş, Y., Kaiser J., Ön, S. A., Eris, K., Garczynski, B. & Horgan, B. H. (2020). Biotic and abiotic imprints on Mg-Rich stromatolites: Lessons from Lake Salda, SW Turkey. Geomicrobiology Journal, 37, 401–425. https://10.1080/01490451.2019.1710784
12. Baldes, M. J. Gong, J., Trejo, D., Balcı, N., Güneş, Y., Tamura, N. & Bosak, T. (2025, inceleme de). Microbial polymers influence the mineralogy and organic preservation potential of hydrated magnesium carbonate minerals (İnceleme de).
13. Braithwaite, C. J. R. & Zedef, V. (1994). Living hydromagnesite stromatolites from Turkey. Sedimentary Geology, 92, 1–5.
14. Braithwaite, C. J. R. & Zedef, V. (1996). Hydromagnesite stromatolites and sediments in an alkaline lake, Salda Gölü, Turkey. Journal of Sedimentary Research, 66, 91–1002. https://doi.org/10.1306/D426845F-2B26-11D7-8648000102C1865D
15. Brasier, A. T., Rogerson, M. R., Mercedes-Martin, R., Vonhof, H. B. & Reijmer, J. J. G. (2015). A test of the biogenicity criteria established for microfossils and stromatolites on Quaternary Tufa and Speleothem materials formed in the “Twilight Zone” at Caerwys, UK. Astrobiology, 15, 883–900. https://doi.org/10.1089/ast.2015.1293
16. Brasier, A., Wacey, D., Rogerson, M., Guagliardo, P., Saunders, M., Kellner, S., Mercedes-Martin, R., Prior, T., Taylor, C., Matthews, A. & Reijmer, J. (2018). A microbial role in the construction of Mono Lake carbonate chimneys?. Geobiology, 16, 540–555. https://doi.org/10.1111/gbi.12292
17. Braissant, O., Cailleau, G., Dupraz, C. & Verrecchia, E. P. (2003). Bacterially induced mineralization of calcium carbonate in terrestrial environments: the role of exopolysaccharides and amino acids. Journal of Sedimentary Research, 73, 485– 490. https://doi.org/10.1306/111302730485
18. Burne, R. V., Moore, L. S., Christy, A.G., Troitzsch, U., King, P.L., Carnerup, A. M. & Hamilton, P.J. (2014). Stevensite in the modern thrombolites of Lake Clifton, Western Australia: a missing link in microbialite mineralization?. Geology, 42, 575–578. https://doi.org/10.1130/G35484.1
19. Chagas, A. P., Webb, G. E., Burne, R. V. & Southam, G. (2016). Modern lacustrine microbialites: Towards a synthesis of aqueous and carbonate geochemistry and mineralogy. Earth-Science. Reviews, 162, 338–363. https://doi.org/10.1016/j.earscirev.2016.09.012
20. Corsetti, F. A. & Storrie-Lombardi, M.C. (2003). Lossless compression of stromatolite images: a biogenicity index?. Astrobiology, 3, 649–655. https://doi.org/10.1089/153110703322735980
21. De Boever, E., Foubert, A., Lopez, B., Swennen, R., Jaworowski, C., Özkul, M. & Virgone, A. (2017a). Comparative study of the Pleistocene Cakmak quarry (Denizli Basin, Turkey) and modern Mammoth Hot Springs deposits (Yellowstone National Park, USA). Quaternary. International, 437, 129–146. https://doi.org/10.1016/j.quaint.2016.09.011
22. De Boever, E., Brasier, A.T., Foubert, A. ve Kele, S. (2017b). What do we really know about early diagenesis of non-marine carbonates?. Sedimentary Geology, 361, 25–51. https://doi.org/10.1016/j.sedgeo.2017.09.011
23. Dupraz, C., Reid, R. P., Braissant, O., Decho, A. W., Norman, R. S. & Visscher, P. T. (2009). Processes of carbonate precipitation in modern microbial mats. Earth-Science Reviews, 96, 141–162. https://doi.org/10.1016/j.earscirev.2008.10.005
24. Ferris, F. G., Thompson, J. B. & Beveridge, T. J. (1997). Modern freshwater microbialites from Kelly Lake, British Columbia, Canada. Palaios, 12, 213–219. https://doi.org/10.2307/3515423
25. Frantz, C. M. (2015) They might be giants: colossal lacustrine stromatolites. Geology, 43 (8), 751–752. https://doi.org/10.1130/focus082015.1
26. Garczynski, B. J., Horgan, B., Kah, L. C., Balcı, N. & Güneş, Y. (2019). Searching for potential biosignatures in Jezero Crater with Mars 2020. A spectral investigation of terrestrial lacustrine carbonate analogs. Lunar Planetary Contributions, 2089.
27. Garczynski, B. J., Horgan, B., Kah, L.C., Balcı, N., Güneş, Y., Williford, K. H. & Cloutis, E. A. (2020) Investigating the origin of carbonate deposits in Jezero Crater: Mineralogy of a fluviolacustrine analog at Lake Salda, Turkey. Lunar Planetary Contributions, 2326, 2128.
28. Gérard, E., Ménez, B., Couradeau, E., Moreira, D., Benzerara, K., Tavera, R. & López-García, P. (2013). Specific carbonate–microbe interactions in the modern microbialites of Lake Alchichica (Mexico). The ISME Journal, 7, 1997–2009. https://doi.org/10.1038/ismej.2013.81
29. Ginsburg, R.N. (1991). Controversies about stromatolites: vices and virtues. In D. W. Müller, J. A. McKenzie, & H. Weissert (Eds.), Controversies in Modern Geology, London, UK, Harcourt Brace Jovanovich (Academic Press), 25–36.
30. González-López, J., Rodelas, B., Pozo, C., Salmerón-López, V., Martínez-Toledo, M. V. & Salmerón, V. (2005). Liberation of amino acids by heterotrophic nitrogen fixing bacteria. Amino Acids, 28(4), 363-7.
31. Gomez, F. J., Kah, L. C., Bartley, J. K. & Astini, R. A. (2014). Microbialites in a high‐altitude Andean lake: Multiple controls on carbonate precipitation and lamina accretion. Palaios, 29, 233–249.
32. Grotzinger, J. P. & Knoll, A. H. (1999) Stromatolites in Precambrian carbonates: evolutionary mileposts or environmental dipsticks?. Annual Review of Earth Planetary Sciences, 27, 313–358. https://doi.org/10.1146/annurev.earth.27.1.313
33. Grotzinger, J. P. & Rothman, D. H. (1996). An abiotic model for stromatolite morphogenesis. Nature, 383, 423–425. https://doi.org/10.1038/383423a0
34. Güneş, Y. & Balcı, N. (2021). The Catalytic Effect of the Heterotrophic Bacterium Virgibacillusmarismortui on Basaltic Rock Dissolution Under Excess Nutrient Conditions, Geomicrobiology Journal, 38, 4, 315-328. https://doi.org/10.1080/01490451.2020.1852453
35. Güneş, Y., Baldes, M. J., Gong, J., Bosak, T. & Balcı, N. (2022) Morphospace, composition and texture of Lake Salda microbialites. EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-395.
36. Güneş, Y., Sekerci, F., Avcı, B., Ettema, T. & Balcı, N. (2024). Morphological and Microbial Diversity of Hydromagnesite Microbialites in Lake Salda: A Mars Analog Alkaline Lake. Geobiology, 22, Article e12619. https://doi.org/10.1111/gbi.12619
37. Horgan, B., Anderson, R., Dromart, G., Amador, E. & Rice, M. (2020) The mineral diversity of Jezero crater: Evidence for possible lacustrine carbonates. Icarus, 339, Article113526.
38. Kazanci, N., Girgin, S. & Dügel, M. (2004). On the limnology of Salda Lake, a large and deep soda lake in southwestern Turkey: future management proposals, aquatic conservation. Aquatic Conservation: Marine and Freshwater Ecosystems, 14(2), 151–162. https://doi.org/10.1002/aqc.609
39. Kempe, S. & Kaźmierczak, J. (1993). Satonda Crater Lake, Indonesia: Hydrogeochemistry and bicarbonates. Facies, 28, 1–31.
40. Meister, P. (2013) Two opposing effects of sulfate reduction on calcite and dolomite precipitation in marine, hypersaline and alkaline environments. Geology, 41, 499–502. https://doi.org/10.1130/G34639C.1
41. Meister, P. (2014) Two opposing effects of sulfate reduction on carbonate precipitation in normal marine, hypersaline, and alkaline environments: REPLY. Geology, 42, 315. https://doi.org/10.1130/G35240Y.1
42. Petryshyn V. A., Junkins E. N., Stamps B. W., Bailey J. V., Stevenson, B. S., Spear J. R. & Corsetti F. A. (2021). Builders, tenants, and squatters: The origins of genetic material in modern stromatolites. Geobiology, 19, 261– 277. https://doi.org/10.1111/gbi.12429
43. Reid, R. P., Macintyre, I. G., Browne, K. M., Steneck, R. S. & Miller, T. (1995) Modern marine stromatolites in the Exuma Cays, Bahamas: uncommonly common. Facies, 33, 1–18. https://doi.org/10.1007/BF02537442
44. Riding, R. (2006) Cyanobacterial calcification, carbon dioxide concentrating mechanisms, and Proterozoic-Cambrian changes in atmospheric composition. Geobiology, 4, 299–316. https://doi.org/10.1111/j.1472-4669.2006.00087.x
45. Riding, R. (2000). Microbial carbonates: the geological record of calcified bacterial-algal mats and biofilms. Sedimentology, 27, 179–214. https://doi.org/10.1046/j.1365-3091.2000.00003.x
46. Rivadeneyra, M. A., Paraga, J., Delgado, G., Ramos-Coemenzana, A. & Delgado, G. (2004). Biomineralization of carbonates by Halobacillus trueperi in solid and liquid media with different salinities. FEMS Microbiol Ecology, 48, 39–46. https://doi.org/10.1016/j.femsec.2003.12.008
47. Rivadeneyra, M-A., Delgado, G., Soriano, M., Ramos-Cormenzana, A. & Delgado, R. (1999). Biomineralization of carbonates by Marinococcus albus and Marinococcus halophilus isolated from Salar de Atacame (Chili). Current Microbiology, 39, 53–57. https://doi.org/10.1007/PL00006827
48. Russell, M. J., Ingham, J.K., Zedef, V., Maktav, D., Sunar, F., Hall, A. J. & Fallick, A.E. (1999). Search for signs of ancient life on Mars: Expectations from hydromagnesite microbialites, Salda Lake, Turkey. Journal of the Geological Society, 156, 869–888. https://doi.org/10.1144/gsjgs.156.5.0869
49. Sánchez-Román, M., Romanek, C.S., Fernández-Remolar, D. C., Sánchez-Navas, A., McKenzie, J. A., Pibernat, R. A. & Vásconcelos, C. (2011). Aerobic biomineralization of Mg-rich carbonates: Implications for natural environments. Chemical Geology, 281, 143–150. https://doi.org/10.1016/j.chemgeo.2010.11.020
50. Sanz-Montero, M. E., Cabestrero, O. & Sánchez-Román, M. (2019). Microbial Mg-rich Carbonates in an Extreme Alkaline Lake (Las Eras, Central Spain) Frontiers in Microbiology, 10, 148. https://doi.org/10.3389/fmicb.2019.00148
51. Şenel, M., Akyürek, B., Can, N., Aksay, A., Pehlivan, N., Bulut, V. ve Aydal, N. (1997). 1:100.000 ölçekli Türkiye Jeoloji Haritası, Denizli M23 (J9). Maden Tetkik ve Arama Genel Müdürlüğü Yayını, Ankara.
52. Schmid, H. (1987). Turkey’s Salda Lake: A genetic model for Australia’s newly discovered magnesite deposits. Industrial Minerals, 239, 19–31.
53. Schopf, J. W. (2006). Fossil evidence of Archaean life. Philosophical Transactions of the Royal Society B 361, 869–885. https://doi.org/10.1098/rstb.2006.1834
54. Shirokova, L.S., Mavromatis, V., Bundeleva, I.A., Pokrovsky, O. S., Bénézeth, P., Gérard, E., Pearce, C. R. & Oelkers, E. H. (2013). Using Mg Isotopes to Trace Cyanobacterially Mediated Magnesium Carbonate Precipitation in Alkaline Lakes. Aquatic Geochemistry 19, 1–24. https://doi.org/10.1007/s10498-012-9174-3
55. Van Kranendonk, M. J., Philipot, P., Lepot, K., Bodorkos, S. & Pirajno, F. (2008) Geological setting of Earth’s oldest fossils in the ca. 3.5 Ga Dresser Formation, Pilbara Craton, Western Australia. Precambrian Research, 167, 93–124. https://doi.org/10.1016/j.precamres.2008.07.003
56. Varol, S., Davraz, A., Şener, Ş., Şener, E., Aksever, F., Kırkan, B. & Tokgözlü, A. (2021). Assessment of groundwater quality and usability of Salda Lake Basin (Burdur/Turkey) and health risk related to arsenic pollution. Journal of Environmental Health Science. Engineering, 19, 681–706. https://doi.org/10.1007/s40201-021-00638-5
57. Wacey, D., Kilburn, M. R., Saunders, M., Cliff, J. & Brasier, M. D. (2011). Microfossils of sulphur-metabolizing cells in ∼3.4 billion-year-old rocks of Western Australia. Nature Geosciences, 4, 698–70. https://doi.org/10.1038/ngeo1238