Use "?" for one missing letter: pu?zle. Use "*" for any number of letters: p*zle. Or combine: cros?w*d
Select number of letters in the word, enter letters you have, and find words!
Sapropel (a contraction of ancient Greek words sapros and pelos, meaning putrefaction and mud, respectively) is a term used in marine geology to describe dark-coloured sediments that are rich in organic matter. Most studies of sapropel formation mechanisms infer some degree of reduced deep-water. — “Sapropel - Wikipedia, the free encyclopedia”, en.wikipedia.org
Sapropel is part of WikiProject Geology, an attempt at creating a standardized, informative, comprehensive and easy-to-use geology resource. If you would like to participate, you can choose to edit this article, or visit the project page for more information. Stub. — “Talk:Sapropel - Wikipedia, the free encyclopedia”, en.wikipedia.org
The biggest deposits of commercial potential are near Aleksinac and Vina-Zubetin. Serbian oil shale is of sapropel type (Aleksinac, Mionica and Petnica) and sapropel-coaly type.  History of exploration. Although oil shale was known. — “Oil shale in Serbia - Wikipedia, the free encyclopedia”, en.wikipedia.org