Consider a simple domain involving a hopper full of gravel and two trucks.
In the absence of gravel deposits, roads outside the shell ridge area are often surfaced with pulverized shell material.
One specimen comes from a gravel pit, and another specimen was found buried in sediments below the marine limit.
Fine-grained sediments, intercalated between two gravel deposits and also rich in plant macrofossils, occur at the base of the exposure.
The floor was covered with gravel to control weeds and prevent puddles during the rainy season.
Extractors often mixed fossil copal with inferior copal resins, and sometimes with other adulterants like sand and gravel in attempts to inflate the price.
To the south there is a gravel and clay wady.
Tubs were filled with sandy secondary forest topsoil over 5 cm of coarse gravel.
