white chert造句

• These rock fragments include chalky-white chert derived from the middle member.
• The middle of this member contains numerous thin discontinuous beds of chalky-white chert.
• Redwall is composed of thick-bedded, dark brown to bluish gray limestone and dolomite with white chert nodules mixed in.
• They may represent the last phases of the Maritime Archaic, as they contain significant finds of white chert artifacts common to other Maritime Archaic sites.
• Many rounded to subangular felsic and mafic volcanic fragments are known to occur in the unit, as well as rare quartz vein fragments and one fragment of white chert.
• Its lower part consists of brownish-gray, interbedded finely crystalline dolomite and fine-to coarse-grained limestone with layers of white chert lenses and yellowish-gray and brownish-gray, cliff-forming, thick-bedded, fine-grained dolomite.