Abstract:
Sedjrrlents deposited in the Late Quaternary marine sUbrnergences that
follov'ted the deglaciation of Ontario} Quebec., and 6ritlst-1 Columbia often
contaln an abundant nlarlne invertebrate macrofauna. The rnacrofauna~
dotYllnated by aragonitic pelecypods} is fully preserved In their original
mineralogy and cherrlistry 8S deternl1ned by x-ray dlffractlon., scannlng
electron tl-,lcroscoDY., trace and r1l1 nor elet11ent analyses and stable isotopes.
Ttle trace elernent and stable isotope geochen-Ilstry of chernlcal1y
unaltered aragorlitlc molluscs can be used to determine paleoter1-lperatures
and paleosallnltles." HO\Never} corrections need to be tllade \fvtlen
deterrTIlnlng oxygen-isotope paleotenlperi:ttures due to the lnfluence of
isotopically 11gtlt glaciol rneltv-laters and reduced sal1nltles. Ttle eastern
Laurentide Ice Sheet probably had an o:~ygen lS0tOP1C composition as low as
-8e) 0/00 (Sr1[IW). In additl0fl} corrections need to be rnade to the carbonlsotope
values, before salinity deterrnlnatlons are t11ade., due to the
reJjuctlon of the terrestrial carbon bl0rnass during glac1al maxlrna.
Using geochernlcal data frot11 537 marlne n-'8crolnvertebrates frorTI 72
localities in soutt-,easter Ontarl0 and southern Quebec, it tras been
deterrnined that the Late Quaternary Char1lplaln Sea \N6S density stratified
along salinity and temperatlJre gradients. The deep-\h/aters of tt-,e Charnplaln
Sea tlad salinities that ranged frorn 31 to 36 ppt} and terrlperatures of 00 to
5°C. Conversely.. the st1alloy./-\f*later regirrle of ttle Ctlarnplaln Sea tlad
sal1nltles that ranged fron-, 24 to 33 ppt} Y.tltt1 terrlperatures ranglng from 5°
to 15°C.
Tr,8 rrlajorl rnlnor1 and trace e1et1-,ent geochernlcal analysls of 155
marine lnvertebrates frorn 4 10C611t1es of tt-,e Late Quaternary Ft. Langley Forrnatlon and Capl1ano Sedlments;. souttl\Nestern Brltlsh Columblal suggest l
t~lat the 'waters of the o-,arlne lnundation that fol1o....ved the retreating
Cordl11eran Ice Sheet had sal1nltles ranglng frorn 32 to 3f. DPt.
