Details

Autor(en) / Beteiligte

• Rattas, M
• Lomp, P
• Jõeleht, A

Titel

Carbonate cementation in the late glacial outwash and beach deposits in northern Estonia

Ist Teil von

• Estonian journal of earth sciences, 2014-03, Vol.63 (1), p.30-30

Ort / Verlag

Tallinn: Teaduste Akadeemia Kirjastus (Estonian Academy Publishers)

Erscheinungsjahr

2014

Link zum Volltext

Quelle

EZB*

Beschreibungen/Notizen

• The sedimentary environments, morphology and formation of carbonate cement in the late glacial glaciofluvial outwash and beach deposits in northern Estonia are discussed. Cementation is observed in well-drained, highly porous carbonaceous debris-rich gravel and sand-forming, resistant ledges in otherwise unconsolidated sediments. The cemented units occur as laterally continuous layers or as isolated lenticular patches with thicknesses from a few centimetres to 3 m. The cement is found in two main morphologies: cement crusts or coatings around detrital grains and massive cement almost entirely filling interparticle pores and intraparticle voids. It is exclusively composed of low-Mg calcite with angular equant to slightly elongated rhombohedral and scalenohedral or prismatic crystals, which indicate precipitation from meteoric or connate fresh surface water and/or near-surface groundwater under low to moderate supersaturation and flow conditions. The absence of organic structures within the cement suggests that, cementation is essentially inorganic. The cement exhibits both meteoric vadose and phreatic features and most probably occurred close to the vadose-phreatic interface, where the conditions were transitional and/or fluctuating.