|The effect of rock hardness and other factors on the shape of the burrow of the rock-boring clam, Penitella penita|
|Evans, J.W. (1968). The effect of rock hardness and other factors on the shape of the burrow of the rock-boring clam, Penitella penita. Palaeogeogr. Palaeoclimatol. Palaeoecol. 4(4): 271-278. hdl.handle.net/10.1016/0031-0182(68)90094-1|
|In: Palaeogeography, Palaeoclimatology, Palaeoecology. Elsevier: Amsterdam. ISSN 0031-0182, more|
Penitella penita, a west coast rock-boring clam, forms a conical burrow in the rock the shape of which is controlled by a number of environmental variables. The most important of these being substrate hardness.
A method for determining the relative friability hardness of sandstone is described.
The possibility that this information could be used by the paleontologist to establish the hardness of sedimentary rock at known times in the past is discussed.