In Poland, chalk is the name traditionally given to two different mineral raw materials: lacustrine chalk (calcareous tufa) and proper chalk rock (still often called as ”writing chalk” in Polish literature). The raw materials differ in origin and chemical composition and use.
Lacustrine chalk, also known as „meadow limestone” or „lacustrine limestone”, is a calcareous sediment of the Quaternary age, associated mainly with post-lacustrine series formed in times of the Last Glaciation. It is used in agriculture as calcareous fertilizer. Accumulations of lacustrine chalk occur mainly in northern and north-western Poland, often at the base of deposits of peat and calcareous gyttja. Chalk deposits occurrence is presented on the map.
Chalk is a weakly coherent and porous limestone rock, mainly used in the manufacture of rubber, paper, chemicals, dyes and cement. Cretaceous limestones of the chalk type used in production of cement (Chełm deposit) are discussed in the section dealing with limestone and marl raw material of the cement industry. Chalk deposits found in north-eastern Poland are related to erratics of Cretaceous chalk embedded in Quaternary glacial sediments (for example, the Mielnik and Kornica deposits).
According to the Regulation of the Minster of the Environment there are the limit values of the parameters that defines the deposit:
- proper chalk (“writing chalk”) is being documented to the depth of 70 m, with maximum overburden of 15 m, maximum ratio of overburden to deposit thickness of 0.2 and minimum alkalinity (CaO) of 80 %;
- lacustrine chalk is being documented with minimum deposit thickness of 1 m, maximum ratio of overburden to deposit thickness of 0.3 and minimum alkalinity (CaO) of 40 %;
The table 1 given below shows resources and the current state of exploration and development of chalk.
Anticipated economic resources of chalk in 2013 amounted to 199.64 million tonnes and increased by 584 thousand tonnes in comparison with the previous year.
There were gyttja resources as co-occurring raw material documented within 3 deposits: Gorszewice AW 2, Wieliszewo and Wieliszewo I (with total resources of these deposits equal 900.13 thousand tonnes).
There were 4 new documentations with recalculated resources approved for 4 deposits: Roszczyce II, Kazimierz III, Kobierniki and Tyczewo I.
In 2013, production of chalk increased by 18.08 thousand tonnes to the level of 165.29 thousand tonnes. Lacustrine chalk production amounted to 27.80 thousand tonnes and writing chalk production to 137.49 thousand tonnes. Lacustrine chalk is being exploited only from Lubiatów and Bełchatów deposits while writing chalk is being exploited from 7 deposits (6 in Mazowieckie Voivodeship and 1 in Podlaskie Voivodeship).
Lucastrine chalk occurr as co-occurring raw material in brown coal deposit Bełchatów – pole Szczerców and is being exploited from this deposit (the resources of the chalk are not officially calculated).
The figure given below shows changes in domestic resources and production of chalk in Poland in the years 1989-2013.
Prepared by: Wojciech Szczygielski