DEPARTMEI,,TEOF GBOmGY-AND-IfiII{ERAIOGT.f SJCFORD. IGIfEOUS ACTIVITY COURSE DemonstratLon 3. vor,c4lglo,Rpcicg 0F' CqAIEFIAI{$ Examlno the noeks and. sections from Cnater take ( the ord,er of the rocks ls ehnonol.ogleal, except that No.13 ehould. come before No.14). On the evldence of.these nocks: 1. Compare the more baelc r.ocks of Orater l.lalre wtth the baea].te of Hawall, Ign.Act.V F & H, and the Brltlsh Tertlary provlneet Ign.Aet.IID&Vg. 2. Deecrlbe and. flgune the textural featunee of the tntesned.late and. ac1d. nocks. 3. Llst and brlefly descnlbe the mlneraLs occunrtng as pheno- cryete in the rocks 1n ord.er from baslc to aqid and aLso consid'er the l,ist ln nelatlon to the sequence of the rocke of Mount Mazama. xror d'ese-iption anil alaLygis National e-ee Horrel l{,illiams rfThe orelonr-w'trt----6*r"gie " Georogr of crater Lake to Momt 3"k, nu"orirJiulun"" of tLre cascad.e shasia"' rnsiit;im Range souttru*rd. or washingi;rr'prruri*tion !rao, 1gt'., ;'l,4.+T.s1. Typiel olivine basalt of peak Union : voleno (J) . , G,r- Ff a{I F1.4. ::,L;\ <92, 0livjne-aqgite basalt of Union peak Volcano _ Red.Blanket Canyon (!!) lr,t;1" *, f'JJ' ot5: to ,fu ?$uoent centrar- plug of uniqx peak (q) sirn-ilar to analysea voroano ,r, ^ -Z spolimEn;";; from pl,g, Fr. let _ 's*tl'o-r'3lr' lvrto $rpical Mazanaandeeite: Head of sun creek canyon (5!) pt rf _j. *1{id*r'35' wpical Mt. jvibzanaandesiter Dutton Ridge. (tzl) aiiid3f361. vpical and.osi-te of Mourt scott volcano (10) :.'r'r:i:rf,57.Dacite, Red.ctoud. Cliff gAil . pf pf.ZA l.+, . #7.r"t . ,4. - i!''.rlrf.S8. Dacite, C-Ieet.wood.Cove flow--" (1g9a)\'vrsl iinaI. NO. 21 . Faf. 2t . +ci;.i*{sg.*tffi Brimof wineglass(15ru) tlj*irl*r. f .,,3. fl-t"-, t*rT.1p. 'Livine basalt. Flow from Rod.Oone (f f f ) p. rr?[. ,*L*;:Tlr1.r.Allffil"lo. Cmterpeak oincler oone (19) "4ri*11,2.,Tilr""::1Tl*". rimbercrater (175) pf. 1,.s t. tI "$i'*af'6'**ti:li:-*i:tiliitr;"(5{li*ng a'alanchej.n castre cnek canyon, ./rnal. No. 26. N.t{. ."f,.**I#*.In bottlel sarnple of gmnular ,rpuriloe fhlL,f of oLinaotio erutr*ion. (X) tLs,*c-.*-re, * st€d,r,r. *$ e.*.ci- , p7 "t-l a "-u-**c+* *t"Jn* qt&$"{L *.*-L\&.$*}, c.*J.