, 65:38 | Cite as

Oncoids and groundwater calcrete in a continental siliciclastic succession in a fault-controlled basin (Early Permian, Northern Italy)

  • Fabrizio BerraEmail author
  • Fabrizio Felletti
  • Andrea Tessarollo
Original Article


Lower Permian continental deposits of the fault-controlled Orobic Basin (Central Southern Alps; Northern Italy) include alluvial fan facies interfingering with muddy basin-floor deposits, consisting of three facies associations: heterolithic fine-grained siliciclastic facies, laminated sandstone facies, and oncoidal limestone facies. Besides oncoidal and microbial limestones, carbonates occur as nodules in sandy tabular beds within the laminated sandstone facies association. Microfacies analyses distinguish several types of oncoidal carbonate (consisting of an alternation of microbial carbonate and fibrous calcite) and carbonate nodules. Each type of carbonate has been characterized in terms of δ18O and δ13C. The two types of carbonate in the oncoids record a stable δ18O and a slightly varying δ13C, whereas the isotope composition of the calcite in nodules is completely different. Carbonate nodules in sandy beds of the laminated sandstone facies association have a diagenetic origin as indicated by cross-cutting relationships between nodules and lamination; the nodules are interpreted as groundwater calcrete, formed in the subsurface at the top of the unconfined water table. The exclusive sedimentation of oncoidal carbonate facies within siliciclastic deposits indicates that when oncoids were formed in ephemeral shallow ponds, siliciclastic input was minimal. The sedimentological and geochemical characteristics of the studied succession and the stable isotopic composition of the oncoids (the absence of covariance between δ18O and δ13C excludes deposition in evaporating basins) indicate persistent stable conditions for sufficient time to permit growth of centimeter-sized oncoids. Oncoids are interpreted to have formed in spring-fed ponds and outflow channels, with flowing, clean water, at the toe of major alluvial fans. Episodes of rapid delivery of sand and silt-sized sediments by flash floods, with an oscillating water table, caused the observed facies alternation. The precipitation of calcareous cements close to the water table surface produced nodules in sandy layers. Carbonate precipitation within laminated sandstone reduced porosity and permeability, causing a strong compartmentalization in the well-bedded continental succession.


Continental carbonates Early Permian Semi-arid climate Southern Alps of Italy Syndepositional tectonics 



We would like to thank Ausonio Ronchi and Michal Gradziński for the detailed and careful comments that helped us in clarifying and improving the first version of this paper. We also would like to thank the Editor of Facies, Maurice Tucker, for his support.


  1. Alonso-Zarza AM (2003) Palaeoenvironmental significance of palustrine carbonates and calcretes in the geological record. Earth Sci Rev 60(3–4):261–298CrossRefGoogle Scholar
  2. Arakel AV (1991) Evolution of Quaternary duricrusts in Karinga Creek drainage system, central Australian groundwater discharge zone. Aust J Earth Sci 38(3):332–347CrossRefGoogle Scholar
  3. Arthaud F, Matte P (1977) Late Paleozoic strike-slip faulting in Southern Europe and Northern Africa: results of a right lateral shear zone between the Appalachians and the Urals. Geol Soc Am Bull 88:1305–1320CrossRefGoogle Scholar
  4. Berra F, Felletti F (2011) Syndepositional tectonics recorded by soft-sediment deformation and liquefaction structures (continental Lower Permian sediments, Southern Alps, Northern Italy): stratigraphic significance. Sed Geol 235(3):249–263CrossRefGoogle Scholar
  5. Berra F, Tiepolo M, Caironi V, Siletto GB (2015) U-Pb zircon geochronology of the volcanic deposits from the Permian basin of the Orobic Alps (Southern Alps, Lombardy): chronostratigraphic and geological implications. Geol Mag 152:429–443CrossRefGoogle Scholar
  6. Berra F, Felletti F, Tessarollo A (2016) Stratigraphic architecture of a transtensional continental basin in low-latitude semiarid conditions: the permian succession of the Central Orobic Basin (Southern Alps, Italy). J Sediment Res 86(4):408–429CrossRefGoogle Scholar
  7. Beverly EJ, Driese SG, Peppe DJ, Johnson CR, Michel LA, Faith JT, Tryon CA, Sharp WD (2015) Recurrent spring-fed rivers in a Middle to Late Pleistocene semi-arid grassland: implications for environments of early humans in the Lake Victoria Basin, Kenya. Sedimentology 62(6):1611–1635CrossRefGoogle Scholar
  8. Cadel G, Cosi M, Pennacchioni G, Spalla MI (1996) A new map of the Permo-Carboniferous cover and Variscan metamorphic basement in the Central Orobic Alps, Southern Alps-Italy: structural and stratigraphical data. Memorie di Scienze Geologiche di Padova 48:1–53Google Scholar
  9. Cannizzaro C, Venerandi I, Zuffardi P (1984) Iron preconcentration in stromatolites/oncolites: an example from the Lower Permian of the Central Alps. In: Syngenesis and epigenesis in the formation of mineral deposits, pp 342–349CrossRefGoogle Scholar
  10. Casati P (1969) Strutture della formazione di Collio (Permiano inferiore) nelle Alpi Orobie. Natura 60:301–312Google Scholar
  11. Casati P, Gnaccolini M (1967) Geologia delle Alpi Orobie occidentali. Riv Ital Paleontol Stratigr 73:25–162Google Scholar
  12. Cassinis G, Massari F, Neri C, Venturini C (1988) The continental Permian in the Southern Alps (Italy). A review. Zeitschrift fur Geologische Wissenschaften 16:1117–1126Google Scholar
  13. Cassinis G, Perotti C, Ronchi A (2012) Permian continental basins in the Southern Alps (Italy) and peri-mediterranean correlations. Int J Earth Sci 101:129–157CrossRefGoogle Scholar
  14. Davison I (2007) Geology and tectonics of the South Atlantic Brazilian salt basins. Geol Soc Lond Spec Publ 272(1):345–359CrossRefGoogle Scholar
  15. De Sitter LU, de Sitter-Koomans CM (1949) The Geology of the Bergamasc Alps Lombardia Italy. Leidse Geol Meded 14(2):1–257Google Scholar
  16. Della Porta G (2015) Carbonate build-ups in lacustrine, hydrothermal and fluvial settings: comparing depositional geometry, fabric types and geochemical signature. Geol Soc Lond Spec Publ 418:17–68CrossRefGoogle Scholar
  17. Della Porta G, Croci A, Marini M, Kele S (2017) Depositional architecture, facies character and geochemical signature of the Tivoli travertines (Pleistocene, Acque Albule Basin, Central Italy). Rivista Italiana di Paleontologia e Stratigrafia (Research in Paleontology and Stratigraphy) 123(3):487–540Google Scholar
  18. Forcella F, Sciunnach D, Siletto GB (2001) The Lower Permian in the Orobic Anticlines (Lombardy Southern Alps): criteria for field mapping towards a stratigraphic revision of the Collio Formation. In: Cassinis G (ed) Permian continental deposits of Europe and other areas. UnravelledGoogle Scholar
  19. Freytet P, Verrecchia EP (1999) Calcitic radial palisadic fabric in freshwater stromatolites: diagenetic and recrystallized feature or physicochemical sinter crust? Sediment Geol 126:97–102CrossRefGoogle Scholar
  20. Freytet P, Verrecchia EP (2002) Lacustrine and palustrine carbonate petrography: an overview. J Paleolimnol 27(2):221–237CrossRefGoogle Scholar
  21. Freytet P, Kerp H, Broutin J (1996) Permian freshwater stromatolites associated with the conifer shoots Cassinisia orobica Kerp et al.: a very peculiar type of fossilization. Rev Palaeobot Palynol 91:85–105CrossRefGoogle Scholar
  22. Freytet P, Toutin-Morin N, Broutin J, Debriette P, Durand M, El Wartiti M, Gand G, Kerp H, Orszag F, Paquette Y, Ronchi A, Sarfati J (1999) Palaeoecology of non marine algae and stromatolites: Permian of France and adjacent countries. Ann Paléontol 85:99–153CrossRefGoogle Scholar
  23. ISPRA (2012a) Foglio 077 Clusone. Carta Geologica d’Italia alla scala 1(50):000Google Scholar
  24. ISPRA (2012b) Foglio 056 Sondrio. Carta Geologica d’Italia alla scala 1(50):000Google Scholar
  25. Jones B, Renaut RW (1994) Crystal fabrics and microbiota in large pisoliths from Laguna Pastos Grandes, Bolivia. Sedimentology 41(6):1171–1202CrossRefGoogle Scholar
  26. Karcz I (1972) Sedimentary structures formed by flash floods in southern Israel. Sediment Geol 7(3):161–182CrossRefGoogle Scholar
  27. Leng MJ, Marshall JD (2004) Palaeoclimate interpretation of stable isotope data from lake sediment archives. Quatern Sci Rev 23(7–8):811–831CrossRefGoogle Scholar
  28. Mack GH, Cole D, Trevino L (2000) The distribution and discrimination of shallow, authigenic carbonate in the Pliocene-Pleistocene Palomas Basin, southern Rio Grande rift. Geol Soc Am Bull 112:643–656CrossRefGoogle Scholar
  29. Mann AW, Horwitz RC (1979) Groundwater calcrete deposits in Australia some observations from Western Australia. J Geol Soc Aust 26:293–303CrossRefGoogle Scholar
  30. Marchetti L, Ronchi A, Santi G, Voigt S (2015) The Gerola Valley site (Orobic Basin, Northern Italy): a key for understanding late early Permian tetrapod ichnofaunas. Palaeogeogr Palaeoclimatol Palaeoecol 439:97–116CrossRefGoogle Scholar
  31. Marchetti L, Tessarollo A, Felletti F, Ronchi A (2017) Tetrapod footprint paleoecology: behavior, taphonomy and ichnofauna disentangled. a case study from the Lower Permian of the Southern Alps (Italy). Palaios 32(8):506–527CrossRefGoogle Scholar
  32. Muttoni G, Kent DV, Garzanti E, Brack P, Abrahamsen N, Gaetani M (2003) Early Permian Pangea ‘‘B’’ to Late Permian Pangea ‘‘A’’. Earth Planet Sci Lett 215:379–394CrossRefGoogle Scholar
  33. Nehza O, Woo KS, Lee KC (2009) Combined textural and stable isotopic data as proxies for the mid-Cretaceous paleoclimate: a case study of lacustrine stromatolites in the Gyeongsang Basin, SE Korea. Sediment Geol 214(1):85–99CrossRefGoogle Scholar
  34. Nicosia U, Ronchi A, Santi G (2001) Tetrapod footprints from the Lower Permian of western Orobic Basin (N. Italy).” Permian continental deposits of Europe and other areas. Regional reports and correlations. Nat Brescia 25:45–50Google Scholar
  35. Petti FM, Bernardi M, Ashley-Ross MA, Berra F, Tessarollo A, Avanzini M (2014) Transition between terrestrial-submerged walking and swimming revealed by Early Permian amphibian trackways and a new proposal for the nomenclature of compound trace fossil. Palaeogeogr Palaeoclimatol Palaeoecol 410:278–289CrossRefGoogle Scholar
  36. Renaut RW, Gierlowski-Kordesch EH, Dalrymple R, James N (2010) Lakes. Facies Models 4:541–575Google Scholar
  37. Risacher F, Eugster HP (1979) Holocene pisoliths and encrustations associated with spring-fed surface pools, Pastos Grandes, Bolivia. Sedimentology 26:253–270CrossRefGoogle Scholar
  38. Ronchi A, Santi G (2003) Non-marine biota from the Lower Permian of the central Southern Alps (Orobic and Collio basins, N Italy): a key to the paleoenvironment. Geobios 36:749–760CrossRefGoogle Scholar
  39. Ronchi A, Santi G, Confortini F (2005) Biostratigraphy and facies in the continental deposits of the central Orobic Basin: a key section in the Lower Permian of the Southern Alps (Italy). In: Lucas SG, Ziegler K (eds) The Nonmarine Permian, vol 30. New Mexico Museum of Natural History and Sciences, Bulletin, Albuquerque, pp 273–281Google Scholar
  40. Schreiber BC, Smith DB, Schreiber E (1981) Spring peas from New York State; nucleation and growth of fresh water hollow ooliths and pisoliths. J Sediment Res 51:1341–1346Google Scholar
  41. Sciunnach D (2001) The Lower Permian in the Orobic Anticline (Southern Alps, Lombardy): a review based on new stratigraphic data. Riv Ital Paleontol Stratigr 101:47–68Google Scholar
  42. Talbot MR (1990) A review of the palaeohydrological interpretation of carbon and oxygen isotopic ratios in primary lacustrine carbonates. Chem Geol Isotope Geosci Sect 80(4):261–279CrossRefGoogle Scholar
  43. Talbot MR, Kelts K (1990). Paleolimnological signatures from carbon and oxygen isotopic ratios in carbonates from organic carbon‐rich lacustrine sediments. In: Katz BJ (ed) Lacustrine basin exploration: case studies and modern analogs, vol 50. AAPG Mem., pp 88–112Google Scholar
  44. Thompson DL, Stilwell JD, Hall M (2015) Lacustrine carbonate reservoirs from Early Cretaceous rift lakes of Western Gondwana: pre-salt coquinas of Brazil and West Africa. Gondwana Res 28(1):26–51CrossRefGoogle Scholar
  45. Valero Garcés BL (1993) Lacustrine deposition and related volcanism in a transtensional tectonic setting: upper Stephanian-Lower Autunian in the Aragón-Béarn basin, western Pyrenees (Spain-France). Sediment Geol 83:133–160CrossRefGoogle Scholar
  46. Valero Garcés BL, Gierlowski-Kordesch E, Bragonier WA (1997) Pennsylvanian continental cyclothem development: no evidence of direct climatic control in the Upper Freeport Formation (Allegheny Group) of Pennsylvania (northern Appalachian Basin). Sediment Geol 109(3–4):305–319CrossRefGoogle Scholar
  47. Winsborough BM, Seeler JS, Golubic S, Folk RL, Maguire B Jr (1994) Recent fresh-water lacustrine stromatolites, stromatolitic mats and oncoids from northeastern Mexico. In Phanerozoic stromatolites II. Springer, Netherlands, pp 71–100CrossRefGoogle Scholar
  48. Wright VP (2012) Lacustrine carbonates in rift settings: the interaction of volcanic and microbial processes on carbonate deposition. Geol Soc Lond Spec Publ 370:SP370-2CrossRefGoogle Scholar
  49. Zanchi A, Zanchetta S, Berio L, Berra F, Felletti F (2019) Low-angle normal faults record Early Permian extensional tectonics in the Orobic Basin (Southern Alps, N Italy). Ital J Geosci 138:184–201. CrossRefGoogle Scholar

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© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Dipartimento di Scienze della Terra ‘A. Desio’Università degli Studi di MilanoMilanItaly

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