oolite

The fine breccia limestone was mostly composed of calcite oolites with tuff debris (Fig.

Biofilm, biodictyon, biomat microbialite, oolites, stromatolites - geophysiology, global mechanisms and parahistology.

This is supported by the wide distribution of clastic carbonate material, oolites, stromatolites and vertical branching channels (burrows or 'rhizoid' structures), sometimes even at a distance from reconstructed sea shores.

But Minagish oolites contain high-sulphur oils with toxic hydrogen sulphide.

The studied succession consists of 7 lithofacies expanded from Barnolas and Simo (1987) including: boulder-pebble conglomerates, graded pebble conglomerates, graded peloidal-ooid packstones, graded oolites, calcilutites, Posidonia coquina and cherty mudstones.

The south, meanwhile, is a low flat rocky plain, composed by Pliocene through Quaternary limestone and oolites covered by dense forests and bushes.

Upper Paoli beds reveal a well developed oolite bar containing large undeformed oolites with thick cortical rinds, in a very clear spar cement.

This is not necessarily the case for higher parts of the deposits, comprising unaltered calcite oolites (Fig.

Larsen (1942b) made a detailed study of the paragenetic relationships in the evolution of variscite nodules in the Clay Canyon deposit, identifying six stages: (1) variscite formation, followed by fracturing and the introduction of thin black quartz veinlets; (2) banded minerals, primarily crandallite, millisite and wardite, replacing and enclosing variscite while opening up cavities through shrinkage (some variscite nodules were entirely replaced by crandallite); (3) formation of free-growing crystals of gordonite, englishite, montgomeryite and probably overite and kolbeckite in cavities; (4) a minor reversion to crandallite formation from solution as isolated oolites; (5) apatite-group minerals; and finally (6) the limonitic phase (limonite is not present inside any of the nodules).

In the Smackover oolites, which were used to construct the porosity/depth curves in Figure 3, physical and chemical compaction combined account for a loss of 33% of the original 45% porosity (Heydari, 1997).

The oolites at Cedar Hill and Russell Mountain laed us to the conclusion that these bedded ores are of undoubted sedimentary origin.

(6) 1.2 m--dark brown varigrained pelletal-biodetrital dolofloatstone with oolites, small pebbles of light grey dolomudstone and rounded bivalves, gastropods, ostracods (Herrmannina), intercalated with light grey dolomudstone.