Question 2: There is an important distinction to draw between nodules and ________; the latter being formed from
mineral precipitation around some kind of nucleus while the former
is a replacement body.
Question 3: ________ and flint nodules are commonly found in horizontal
layer in limestone and
chalk formations respectively.
Question 5: ________ are rounded accumulations of manganese, iron and other metal oxides that accumulate on the
deep ocean floor.
Question 6: Nodules may be hollow as geodes or vugs or
filled with crystals and intricate geometric shrinkage
patterns as in ________.
Question 7: ________,
formed from mineral precipitation in the pores of a sediment, not
to be confused with nodules
Question 8: A nodule in petrology or ________ is a secondary structure,
generally spherical or irregularly rounded in shape.
Question 9: ________ are also a widespread
source of biogenic silica in marine sediments.