Table 2.

Main features of zeolite occurrences in thin-sections, for the lake margin deposits of Beds I and II.

— Authigenic silicates ——Other diagenetic features —
UnitSampleAnChPhOthfmchccscModeAssociations
Authigenic silicates: An – analcime, Ch – chabazite, Ph – phillipsite, Oth – others (Cl – clinoptilolite, Er – erionite, Kn – kenyaite, Nt – natrolite) [(+)/+/++ signs indicate relative abundance]. Other diagenetic features: fm – Fe/Mn oxides, ch – channels, cc – clay coatings, sc – secondary carbonates [(x)/x/xx signs indicate relative abundance]. Mode of occurrence (for chabazite and phillipsite): g – groundmass, p – pores, s – glass shards, v – volcanic rock fragments, i – infillings, ic – infillings in cracks. Associations: cc – coarse clay coatings, fc – fine clay coatings, afc – authigenic fine clay, fm – Fe/Mn oxides, sc – sparitic carbonates; → sequence (not replacement), + co-occurrence (with no apparent difference in time of development).
BedIIRS32-------xx
RS31--++-----Ph-p/(r)
RS26------xxx
RS24-++-Cl-xx-xCh-pCh → Cl
RS22---Erxxxx-
RS21-------xx
RS19-++------Ch-p-ic
RS17-++-Erx(x)-xCh-pCh → Er
RS16-----x-xx
RS13--------
RS13c-------xx
RS11--------
RS11c----x--xx
RS10-------x
RS9--------
RS7-++---x--Ch-p/(g)-i
RS5-++-Kn-x--Ch-p-iCh → Kn
RS2c-------xx
Bed IZ24-++++-xx---Ch-g/(r), Ph-p/rCh → Ph
3Z-++------Ch-p-ic
ZL-+++-xx-(x)-Ch-g/r, Ph-p/rCh → Ph
ZK-+++-xxxx-Ch-g/r/p-i, Ph-pCh → Ph, Ch → afc → Ch
Z22-+++-xxxxxxCh-g/(r), Ph-p/rCh → Ph
Z19-++--x---Ch-g
Z17-++--x---Ch-p/(r)-i
Z15-+++-xxxx--Ch-g/(r), Ph-p/rCh → Ph
Z11-+++-xxxxxx-Ch-g/p/r, Ph-p/rCh → Ph
Z10-+++-xxxxxxxCh-g/r, Ph-p/rCh → Ph
Z9-++--(x)xx--Ch-p/r-i
Z7-+++----xCh-r/p, Ph-pCh → Ph
Z4-+++-xx-(x)xCh-g/r/p, Ph-p/rCh → afc → Ch, Ch → Ph
Z3--++---x-Ph-g/p/r
Z2----x---
ZJ-+++-xxx-xCh-s, Ph-pPh → fm, Ph → sc
ZI--(+)--x--
ZB-+--xxx--Ch-r/(p)
ZA-+(+)-xxxx--Ch-p-i, Ph-s/(p)Ch → fm