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Sedimentology of the Outer Texas Coast

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Sedimentology of the Outer Texas Coast " ."' / i \t-anjllWi.£^/2i?^^1 7 Sedimentology of the Outer Texas Coast W William Dave Blankenship, B. A. prasaatad It the Pmmltg of the Ctra&*«t* School ©f fto Hmi¥#r»it^ of f©i«i» la partial Aslflllaant of tha Beciulr^aeiits For t3a® B^re® if mmm of AMM fhe osrrafisxn of tmub Vi w» wl£ t illappreelativn ilMil mm «Beoarts«Mie»t Abstract H§ ftatant a* ap#f»3*#»ei*t#& ®& the f#n«s ©oast saqr &c a#p&rstad atoonolngijsslii into tha Xaglealcte, &l&is®£, mm PoaVAlasan or tmmmt times ♥ Each aubaivlsion is associated aUjmti^ with a n&Jor fXmotn&tiaaf th« Xngl«»id« ftud F0»%» Hassan yltfe tte oflr«t0flr«t aM s^oßd oXlaMitl6 I', % rtsp«6tlvely # eai t Altaaa with tbt» "Little Xc« %# » Clsari«st@Fisti^ if th# Xaglealde «»5 ?r#s®at time®, and an& lagoon ayfttema. file ptesmlvgmp&X& teaturaa of the preseist coastal banker ssrst^ foml«ig th# o«t#r f«»» e^mst, «aiilf«at a <Hr«et MAittM to tte ©liaatlci ItJtlftfilllltiil ®f th# Fr4HMHOt# Jtav&rlag onalK>r# aoT«&ant of »«dl®aat®. fhm »«4im€ott sa-rrle4. b> laainland streams to the b®% ayataßMi^ th#a »ov«(l tte©a.gh the fesrri#r passes b^ tidal o^rr#sta, ar# oostrlbated t® a sauttoestwara «^vJ4ag lon^J^^^e enrrtiit. Way® transport aM «<!% aotl©u trajsuit#f th« s^dia#nta to mm %m&mr® Orift oU2^*#atf utoleh it r^ersifel# In dir©etiun with tha loagals&ra c^eponeat of tli€ |OM| wii^# 9ha tl^ittlO if taie IMHi 4rlft mirrant iffflMlli Olraatly th# orlantatipft of f&?aate*a f^tor^st MMMIg Kpi b#tw#tn cmtps, a^ the atsoclat^di ba©k»#^i ahisanelt ®M rlppla Biarks. fto## teala pvoflXM raprasaatlais «^l®# sswl, iM 4 5 storm Vinci ooadltlops raattlt froa MPiUMI or rwoiral |f Barrl&aiiaa, ooourrixig at &m on@ loaaHty ©n the ¥***« aoast about H|t ays*? 23 yaars, pr©4n©# gf*#at hot©® tiMA flood Uui fe«3rrl«r ■y»t«n fti tli# r^ioß ntor# to^ MM traok ero«s#« th# @0a9%1t00. M hssrrlean# flood flatt#a» Icm fore- duoaa, fer#akß ttmmgh g«ps inMg^#r MMiiiMig MMI «®s&o^^ f«n« «iai t^porar^ ps»ae», «od oarrl^ft tli# maturlal aei^>ssi the isl&aa In oh«naels, &®p®nl%im% the s.©aim#atsi In front of 0«ok &i&® fields aiKl in tne lagoon. $hm day portion if tbe pf*@tfmt win*l regime (tJauit £$*## if precipitation) transports Mta Oulf hmm& eanas inlsaa over tte b»rri^ Fr«oipit#tlon, ae<m,i*riiig i»r# often giftfe MMMiittl1 vIJCKIt than irito iWlUlMrtir urincl®, .r#&io#s tine effect of the f^i^er on saM fl»v«Bi«iit* SB is th# |>r<^ralllng triad 41r«ction ei*ei «l«o tiie resultant effective direction omisia^ «#oli®» mvmmmt of m&& over the barrier sy«t«a> pro<Juoin^ a» over*all reaaltftiit HI s^v«m«at. Bloncmt tojagaea, l^ireliaiia, ©»a aalf &§.ia#s of tha barriar «fat4i® # mlm ttem dana fi#l4s aM tfiiis*eiit rldgat and furroira of tkm mainland, hsve 4#¥#lop@a trends in a^r#«m^it with tha W airisetion of a^lian m&m &wm*m%. fha 111 tr#M^ art «iparJUspoe«d on a sand eteet that e®nt#r» at 27*1 latltuda on th© s^inlana ana stands ¥ fwm tM&xm M©Or#, the nM sh«et yes probably the pro^siot of m diff^r^i^ iriad r^ima because of it« i^n^agraafiiant with tha pfesant ttilptiii of 5 * flW^i^MlffWt wfmtF w A gradaal sh&age of pi^tlogrspliio features souto^tstvara aloi^ the coast is the direct result of tke 61ffesrent of sand aov^^iit oorr«^onOiiis with a cllattlo r^o^# from luald in tl)# vicinity of Sabla© Fast to 9m&**®rM on mrt&epn :padra Island* Hetsrt^t^rp© <tos»s f the s#ifs ©asd barcb©us topical of t^« grsst #rga of tlie worlds art fcuad la tl»# s««l«arM portion of t&& fexas &&rrt#s» s^st««* Of th# @ntir# continental sb^rea of th© United States, only alontj t^# festas stores 4o «jch ciunca develop for no other shore in tb# Unltea States Bppa?oaotes the sa^e ci^ree of ari<li%. Table of Contents Xntrodiiotlott ♥ #*##*♥#*#*.♥**♥*♥♥3.2 Background »""*«"««**"««""«« 12 IiMMM ana aaitofttlra " *»"»»«*""" 12 p II J#®%*l^#B *"*»"*««*«»#*«"*" p| i\€kiioirleclgm#ist® *»««*»..«*,"""« 13 Stmeta*.ral tettlag .."""♥**♥*"«*"*#*16 " : Flj>*Blogrsphie getting I■##.*#" # « ♥ # ♥, ♥t« £0 " Floi»too#a® ana raeent gtalagie history . » # « 22 SedUmmtft*? enviroiasitat and interrelatlozui * * " " %5 Btatrifcsntiv® *g«nt» aoa the rWilltig 3«iHse mtm t© b#«th ,**».♥"♥♥♥"#25 * * " * flKiXf beMli "*""«""""** ♥ ♥ 30 fltaXf tofttefe to lagaott beach """#*♥*#♥37 prettnt wiM r«glai* *#*#""»##« 3T jftw)^o'3Wi otliti* $t ttbte #nvif*oite#at I- #» | 43 ?fcysi&gr«pli±« f^ttt&r** ***""«* 45 Earlier iriaa rogSa* .****««.,»"* 60 %ttmt of terrletn#» *""**.»#♥"". 60 Mtto&%; ol* Ess 1* n #.*.#* »*#» * " # " pS Sedimentary ssalyseft " """"*"**»»*""« 64 'Bmtvtor formstloa ***,#**.♥"".#♥ 6? $#l«*eies tetfellogrsptisf *»*«",***#**** 69 7 List of Illustrations Figures Page 1. Zw&mx map ®£ tke featas eoaet ........ la 2* Aerial pitu>togr«pii of aorthersi JiiPl XslanKl. » 11 4. A#3*ial pttot©gr%pti of Arai«N9» F«»# ""«#«« 27 fi Split e3rpoo#a at loir- IMNI .......... 19 Icjw " 6* Spltt as^ btrt #j^o»#di «t tid# « *. 31 7. Basle NMMrtl prcfll»*t mlms UMili * ■ S%O*S * * # ♥ " * " |# * » # ♥ " * * ♥ # ,3:^ S« Usm'n cusp» a»a to«2f» *.»""«.**#*"" 31 9* VftYM imteri«ot.i«g I* fallow water *"* # » 36 B9liiip§'B& 10* elaftzukel ..»..♥"» f ..... 36 " * vet aa^s p«r vlad 41reotio© p#r ytar* . ■" 39 It* Vifid r©st iß&te sting mn**gs tu«b#r of <Sr^ tiftys per vln4 <3JLr«otlo& par ...... 40 13* Wind, iiti iMlestiisg resultant clry wiMi, * " 41 dlr«otlon 0f sand moirfsaiit *"»§** * "< 48 15. For«^utaa« rldg« »«***#♥**""***« %6 16* Sfejmfe*eoppi©#" 4mstt on*southern" *********F#4rt XslaM . i If, Xaolated *et*fc*f*ti tittaa teld to^etter fey roots 18* Boa*€*s!!Brpe4 fWflfftti &i&e. t«**« * * * * 48 191 Bloirout toflgua atraaaisg ffli ova* aeoltan plain ................... 30 20* Leewra aid* of low dune on bloiroat toogue* * 50 8 9 Flgt»re©~~ Fag# 21* Windward side of law &*ne on blotr^at 22. Leev«r<i side of self 6une ridge saving rlpple^msrlced slip-feee and arc »«* bedding expoeecl In 6 subordinate H point ...... 51 S3* XK»##rt*t^p# Ottn« fltli ©hewing B-V treating "elf aunas with olear lan#» between 2-. B«re dunes mxrrounaing live oaks bent HV under prevailing SI viaa* »»"«*«"" 4 5^ SaasKl sculpture fronting a *llp»f&e# la notion ♥".»»«"♥#.##♥♥"♥♥55 86* Looking V along s«lf £an« rl&ge toy*** Laguaa 2?* Slightly inclined resistant lamination* left after ml#ration of dune .♥......♥"39 26. Hittograaa for tables 1 through 5 &5 " £9, Hiategi*®in» for Maples 6 througb 10 ♥"■. 66 Fig. 1. Index map 11 Fig.2. Northern Padre Island 11 Fig .2. Northern Padre Island 11 Fig. 2. Northern Padre Island Introduction Background This stsdy ««" undertaken In parauanee of the writer's interest &n coastal geology aeq&lmd i&Lle vorldas for the Btaob Erosion Board illMaa^iii^toii# D.C « Location and Selection entire outer VeaeM eciatt MM Bafeint f#«» to the ftio ai^Bit E£^#r ftad c tittAllii ettid^ of the mvthem 10 cilles ©f F#te# i»laM OppOtite SM «EKt«QMIIDg «N9UttetVd fftm Co^Ut 6!iriCtl# fexas. Figure 1 is aa ißdess: nfip for looatlons ftwi Figure 2 is mi a#riiil pli®to^«p^ «tevlj)g a portion of the area studied lorthei*E fatoe lsl@aci wa© B#l#et€4 for the &et6lle6 »tu43f for two refteoimi 1) Its aooest-lblllty to s^ fviea Osrpas iritis, Christ! by pm®& roaa oaim^atii^ the ielaM the ualB!&u&# iM also Its «oeeeclbllltQr to ®M from Port Jkransss |p a b#aoh f«n@# dri^e, sM; a) of the *s®tlr# outer IMNMI {i@laM» f paart ptlANdittj and 4#lt®a) # Island the fNMMI ¥srlet^ of p^siosi^i^io featuf*o». Objectives f-fie obj«?otiv## of this tftMii ®^^ follondngt 1} to ssake a detailed stu4jr °^ j^aralographlc f#»ttir#a 12 13 of ih# aorthera ICatlee of F«dr® Island and iti ®4Jno©at ua&esiteter tNHii coasicieriag tte agnate of ttftrtlflrttiil aM toe HiiHttH ®$ transport of aedlttetttsj 2) to ass&e a general stti4y tf the ptts;®tQgi*tphS© features ©f to# #^tlro T®n.a® iMM la ort#i* to relatt pi^operly the arta of detailed attention! 3) To t^t^a^ taXl«nl*» anilytet if flttlf bmvh mMn &ljn& the Texas coast % the GdAltloa of 10 aaaplea %&&m aerotn MlPi XsXaad MMMMI the Half sad I#tgoea treaohes! %} fo obtuls data laliaatiflig teaaoual and iHW Is^ortsat clit«g#a la tte mrm toy fraqaaat tttlt oba#r^atlon» over a of oae jmrs 5) fo obtain ao«M» eom^t of lo^s p®ri®& ohaagea W eo«|>arlaon of all kaovn sets of aerial photographa, mups, JSt-¥M*S Atiki*V*&Ket Acknowledgments Xadabtadaftaa i» lanre ®o3a^?wl#c%^a It the m»m orsaal«atloiia and in*liirl<toi& ite haT# gi^#a genaroaaXy tei&a? e^iotiragea^at IMI taf^yjsatiom al^iag the ©oii^l«stto& if this ata^y. farfcli&sXar #ateowla%m©nt i® iia the Beaoh &*G»loa Boar4, Corpa of &&la*eFsf Vaahlastoa« 1&*G» for their iat#r©®t im the ostopme of thle &%&$$ ani for their g#«^rou» ®i 4in eupplylaiß «wp« *ad at^ial photogrepha* HH i«§« Imrl Mii"* HP HMPSMkI Spiral Mr Station pjroviae«l fjiHttlfii foi* a#rlal HMMVWttaH of fadre 14 Island aad Mustang lelaad frc« &i*n pats to Fort faMMLf fea^a, offering an liwalwable w@^ of st*3%ing the ptiyslograplile featuree of %h® bkrrZm Islands* the O.S* g*vy «t the Corpus HjFJJtI S***! ili1 Station Made a irp^l&i photegraphle flight oV#r Padre Ialand to pr^¥i4e mm up<~ts*date aat of aerial pictography, file o^B.
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