|
<br />Thc moment magnitudc is proportional to thc arca of thc fault planc that has slippcd and thus is
<br />dircctly relatcd to the fault lcngth. l\n carthquake may havc onc momcnt magnitudc but a rangc of
<br />intensities. "Intensity" is a measure of the effect of an earthquake at a specific location. 'l1lC 111USt
<br />commonly uscd mcasurcmcnt of carthquakc intcnsity and ground shaking is thc Modified Mercalli
<br />Intensity S"'al~ (TaLI!;; ""'-I). TIll.; ;lIkll~;ly uf \';ddlu-fual\.; !:;lUUIIJ.;:)lw.kiug ill allY um;; u.n."a val;\..-;:) rUI a
<br />lIU1uLCI uf IC:U;:)UII:'). tlu; 1I1(jelliluJ~ uf tile: \,;dlllu-iu<.lk.\,;, tll\'; Ji:o.l..ull....\.,; vf tin..; ;'lit\'; I~UIII till,:; f:1Ult :"JUltl'--\,.,
<br />till;; Jill",;diull uf pluvagdliulI uf tin; lU}ltUlI;;, allJ tin; t,pl,; uf gl,;ulugi\.. 1IU11\;lial:,,> UIIJl,;llyillg ill\,; ;:)itl,;,
<br />witll ;:,lIVlIgC:l :">hak.illg u\..\,.ulJiug VII :')ufL\,;1 :')ua:'t.zSc!lll~ T!lhl,... V_l ~hnvp <mmm!ln7P" tllf" ~rn{ljfipfl
<br />, ,
<br />~f('rt'!ll1i Intt'fl"lfJ' Sr~l(' (rvfT\H) in tpbtinn tn thE' Hirhtt.r Sr~)l', ~.. \V(.11 !l" I'l'rcrivpc! ..h!1king h~'l!1rd,
<br />rnt('nti~1 rl!1tl1!13p, '.1nrl 1''.lrthcl'l'.lluo {'((PCN '.1'" rl.l~tl'd to grnl1ll(ldl~killg "l'Vl'Mry
<br />
<br />Almost all of thc major faults in tlle Bay l\rea arc strikc-slip faults whcrc thc rupturc along thc fault
<br />planc cxtends almost vcrtically into thc ground, and thc ground on onc side moves past thc ground on
<br />thc othcr sidc. [n some carthquakcs, thc surfacc of thc ground can rlIl'turc along thc fault, or a
<br />landslidc can be triggcrcd, or a numbcr of othcr incidcnts may occur. But in all carthquakcs thc ground
<br />shakes, andJllv~t cdltln1llcl.kl..: JdllldOI.;; i;:') "'au~\,,;d Ly the shaking of the ground itsclf.zr~~I1"::l'''' mn..::t
<br />('~rth(J'I~kp ..-1'lm~gf>
<br />
<br />/l. IIUIIIL\;I vr \;al tl".luak\"; raulL~ al\,,; ",;01"'1 vvitll;1I VI ;11 ",lv~\; }-lIUh;lIl;ty tv tll\,,; l'tokd~(llIlvlI rlclllll;lIg AI",a.
<br />Tllu;,>", ",;01 tll\; IIIV~t J;I\,,;d clllJ pvh.;1I1;cllly d",~l,ud;"", ;III}-lad ilIe tin:; Sail AIIJII.;a;,>, Cala"\";hl.;:,),
<br />Ilay",alJ, GI"''''II,,;lIe, illlJ CUII"'VIJ-GII.;\;II V alky fault;), r;oU'''' V-I ;,>llv",~ tll\; Iv",at;vlI vr fdulb ;11 ullJ
<br />lI\;ul tll\; Plallll;lIl:; /'\1 ",a, allJ TdLle V-21;~b 1111,;;1 ~\";;;'>lIIi", pal(lIlI",kl;:'J. Tin; 11;~tVIY vr "'dltlu'luak\"; dd;,,;ty
<br />alulI!:; tll"'~\"; fa.ulb, tv!:;dlll.:;1 ",;tll 111\.; lIlI;)la.bk lIallll\,,; vf ;)Vllle vf tlli;; ~lIIIUUIIJ;II!:; ;)viILypl,;;:'), iIlJ;",al\"; lln;
<br />l;kd;!lllUJ or a IlhljVI ",a.atl,yuuke w;lll puklll;ally J",,,a:>lal;lIo dT",,,,b \I\I;lll;1I 1I1\; lI\;hl 100 y"'(II;).
<br />F!lrthrll1~kt...:: l~n r~I1"t. ~ 1l11f11hr>r nf "pl"lifir h!l7!lrrl..::
<br />
<br />1 l;rotlllrl Sh!l king
<br />
<br />Portions of thc Planning Arca whichthat arc undcrlain by loosely compactcd soils maytJ,"l"fUl"
<br />cxpericncc the grcatcst amount of ground-shaking and damagc, evcn though thcy may not be closcst ro
<br />the fault nlpture, rigUl\'; V -2 illu~hdk;) till;; dll;;a-wiJ", ;)U~"'\,;pt;La;ly Lv oluUlII.hlwkillg ;11 tin;;
<br />1'1(1.1111;1101'\1\,,;(1.. Otlll;;l putlivlI;) vf till,; rl,ulu;lIg {\I\,;a, \1\11 I; I\,; plvLalJly ;)uffl.;I;lIg k;:');) Jalllagc flUlI1
<br />gIUlIIIJ-;)lwkillg, IIIa.y \,,;hP\,;I;\,;U"'\,; vtll"'l ;)1;;;;)lIli",aIlY-ldak;J iIlIPd",b.
<br />
<br />t\" <.:.hn\\1n nn '<'igllrr> V_" !lll(l flu'th,'r rl,...::rrilwr1 in 'I'!lhl,. V_1, ~h(wf>, tll(> grollllrl_..::h!lking h!l7!lnl in tIll'
<br />Pll'!l"!ltltOtl PI~l1l1ing An'~ i.. 1l1n..t1y mith'll th,. "<.:.f>Vf>t,." tn "vinlt.ntH r~ng(' J)!I'''!lg'' rl"<':'l1lting frntn
<br />",'Vf>rf> grrmnd..h~king \\10111,1 hI" 'T\nl1f>rMp tn lll'~'-'Y \\fhil" d~lT\!lgl" dill" tn v1nl,.nt grnllnlkh~king \\1nlllcl
<br />hI' hp~v)' 'l1w intl"ll...ity nf "!Irthr]1l!lkt. grnllnrl ..h~king 111 ~I1Y nn,. ~rp!I v~ri"", fnr !l nJnnlwr nf rp~..nl1<':"
<br />thr> m~gnihH1p nf tit(' "!Irth(pl~kt.. the. di<.:.t!lnrl' from tit(' ...,tl" nf tll(' f~l1lt "::nlln"p' tit(' r1;"I~rt'nl1 nf
<br />prnr!lBJ1t1nn of thp nlphlt'p. ...n,1 "::!lhlr!ltinn or grnllnclm!ltPr' !lnd tlw typP nf gpolqg,r m!ltl'rl!ll...
<br />IInrll'rlying thp ""tf>, \Vith ..::trnng,'r dl!lking 011l1l'r1ng nn the. ..oftl'r ..nil..
<br />
<br />? F~rtll(p'!lkf>_n("bt("(11 !lntklidl''''
<br />
<br />+:---Lundslides could occur generally in areas shown in riglln; V-J,FigJlrf> V_1, ~hnV(', us a result of
<br />grnllnll"h~killg ~nll nthpr rhy..ir~t Inn(litlnn<.:. ~... di..::rll..::..::,.d ~hnvp
<br />
<br />l:;IUUIIJ;:')}IUk;ug.T1w r!ll1"::p,,:: of ..::lnr" f~ilHn', \\1hlrh nortl1!llly prndlln' l!lnrldidp... !ltl(l diff,.rpnt;~1
<br />"::l.ttlpml'nt, !In' !lllgtnPntP(l ,.-ll1rlng p~rthqtl!lk,.... hy ..::tr(lng grnllnll mntinn 1\n earth(luake occurring in
<br />
<br />Public Safl'ly 082906, fl.xllinc
<br />
<br />v-s
<br />
<br />City COllllCi18/29/2006
<br />
|