“…Pery is derived from biological precursors during post-depositional diagenesis in terrigenous sources (Aizenshtat, 1973, Laflamme and Hites, 1978, Hites et al, 1980, Tan and Heit, 1981, Tan et al, 1996, Jiang et al, 1998, Grice et al, 2009. It has been derived from both aquatic and continental organic matters under the influence of prolong reducing environments (Aizenshtat, 1973, Wakeham et al, 1979, Silliman et al, 2000, Suzuki et al, 2010. Pery may also originate from diatomaceous sediments (Wakeham et al, 1979, Venkatesan, 1988.…”