They formed in clayey sediments, soft shales, or basic rocks, in association with Aridisols and with aridic subgroups of Ustolls.
(They; formed; L:in clayey sediments, soft shales, or basic rocks, in association with Aridisols and with aridic subgroups of Ustolls)
They
formed
L:in clayey sediments, soft shales, or basic rocks, in association with Aridisols and with aridic subgroups of Ustolls