▁or ▁ ▁ge ological ▁units ▁of ▁considerable ▁size . ▁ ▁The ▁former ▁are ▁described ▁in ▁detail ▁below ; ▁the ▁larger ▁ge ological ▁units ▁are ▁discussed ▁elsewhere ▁under ▁bars . ▁ ▁There ▁are ▁several ▁consp ic uous ▁parts ▁to ▁a ▁beach ▁that ▁relate ▁to ▁the ▁processes ▁that ▁form ▁and ▁shape ▁it . ▁The ▁part ▁mostly ▁above ▁water ▁( dep ending ▁upon ▁t ide ), ▁and ▁more ▁or ▁less ▁act ively ▁influenced ▁by ▁the ▁waves ▁at ▁some ▁point ▁in ▁the ▁t ide , ▁is ▁term ed ▁the ▁beach ▁b erm . ▁The ▁b erm ▁is ▁the ▁depos it ▁of ▁material ▁compr ising ▁the ▁active ▁sh or eline . ▁The ▁b erm ▁has ▁a ▁cr est ▁( top ) ▁and ▁a ▁face — the ▁latter ▁being ▁the ▁slope ▁leading ▁down ▁towards ▁the ▁water ▁from ▁the ▁cr est . ▁At ▁the ▁very ▁bottom ▁of ▁the ▁face , ▁there ▁may ▁be ▁a ▁tr ough , ▁and ▁further ▁sea ward ▁one ▁or ▁more ▁long ▁shore ▁bars : ▁slightly ▁raised , ▁under water ▁emb ank ments ▁formed ▁where ▁the ▁waves ▁first ▁start ▁to ▁break . ▁ ▁The ▁sand ▁depos it ▁may ▁extend ▁well ▁in land ▁from ▁the ▁b erm ▁cr est , ▁where ▁there ▁may ▁be ▁evidence ▁of ▁one ▁or ▁more ▁older ▁cr ests ▁( the ▁storm ▁beach ) ▁resulting ▁from ▁very ▁large ▁storm ▁waves ▁and ▁beyond ▁the ▁influence ▁of ▁the ▁normal ▁waves . ▁At ▁some ▁point ▁the ▁influence ▁of ▁the ▁waves ▁( even ▁storm ▁waves ) ▁on ▁the ▁material ▁compr ising ▁the ▁beach ▁stops , ▁and ▁if ▁the ▁particles