WPC  A,sj.UB@)-bkJ3OM$!{M[&^(JOe;X]ɡ`\-D37iD3J_{# o:.oYd(b.qR:Y2JCtDOg%"hM/ qa9vO[u5֜R!SIRmc>hW S *UԶr~\o[d]`~̋ m.eaBNËO!uVqp$iY/3d{Y•'{Eil]lTa|  k˂j[i|H80‹5/ckAvMzU<~ 0<zp 0UN %\#!bw:4 mN^ U;: 0d: 0R 0A 0 T1 0h 0|  i b} b \  `$Times NewRoman<:Default Para'  Fred 0 .   3|x (fq3$  6XX66xuH Z6Times New Roman RegularXHP LaserJet 5P/5MP Po (Copy 2)0 EDUDee vQ&|iL~ U Jc&,*AZ"Arial Regular(Wf|$ @*  A (W$    (Vm$0   (,!$0  0` (#(#  (@$0  0` (#(#0 ` (#` (# ` (T$0  0` (#(#0 ` (#` (#0 (# (# - - q3!  VXXV  _    L? 8 Xdd8__RetrievingandUnpackingSDTSData    ! L?TutorialandUsersManual#L?  ! #  Z   L?June23,1998#L?   -#  ! L? >    ! ^y _NeithertheU.S.Governmentnoranyagencythereofnoranyoftheiremployeesmakeanywarranty,expressedorimplied,orassume   anylegalresponsibilityfortheaccuracy,completeness,orusefulnessofanyinformation,apparatus,product,orprocessdisclosedhereinorrepresentthatitsusewouldnotinfringeprivatelyownedrights.Referencetoanyspecificcommercialproduct,process,orservicebytradename,trademark,manufacturer,orotherwisedoesnotnecessarilyconstituteorimplyitsendorsement,recommendation,orfavoringbytheU.S.Governmentoranyagencythereof.# _^y#    Vm  Vm0 4    1.Introduction#!!G!.  4!4!#1Vm݌    Ќ  Vm  Vm_0 4    2.OverviewofDLG/SDTSandDEM/SDTSData#!!G!.54!4!#2Vm_{݌ 0  Ќ  !  !80 4 0 4!4! 4   2.1SDTSOverview#!!G!.,,# ! !#2!8S݌ B  Ќ  !  ! 0 4 0 4!4! 4   2.2MassConversionofUSGSDatatoSDTS#!!G!.: ! !#2! (݌   Ќ  !  !0 4 0 4!4! 4   2.3SalesandDistributionPolicies#!!G!.VV5 ! !#3! ݌ v  Ќ  !  ! 0 4 0 4!4! 4   2.4SDTSdataorganization#!!G!.vv, ! !#3! ݌ 8  Ќ     0 4 0 4!4!0 ! !   2.4.1DLG/SDTSData#!!G!.::* ! !#3 ݌ J Ќ     0 4 0 4!4!0 ! !   2.4.2DEM/SDTSData#!!G!.+ ! !#4 ݌   Ќ  Vm  Vm 0 4    3.SummaryofDataRetrievalProcedures#!!G!.::44!4!#4Vm ݌ @ Ќ  !  !m 0 4 0 4!4! 4   3.1DLG/SDTSData#!!G!.((" ! !#4!m ݌ R Ќ  !  !A0 4 0 4!4! 4   3.2DEM/SDTSData#!!G!.BB" ! !#5!A\݌  Ќ  Vm  Vm0 4    4.DetailedInstructionsforRetrievingSDTSData#!!G!.XX>4!4!#5Vm1݌ H Ќ  !  !0 4 0 4!4! 4   4.1CreateLocalDirectory#!!G!., ! !#6!݌  Z Ќ  !  !0 4 0 4!4! 4   4.2FindandRetrieveData#!!G!.@@, ! !#6!݌  Ќ    0 4 0 4!4!0 ! !   4.2.1FindandRetrieveDLG/SDTSData#!!G!.= ! !#6݌  Ќ    0 4 0 4!4!0 ! !0< ! !   4.2.1.1DLG/SDTSTransportationOverlay:ASpecialCase#!!G!.R<!<!#7݌ P Ќ    0 4 0 4!4!0 ! !0< ! !   4.2.1.2RetrievetheDLG/SDTSMasterDataDictionary#!!G!.""P<!<!#7݌ b Ќ    0 4 0 4!4!0 ! !   4.2.2FindandRetrieveDEM/SDTSData#!!G!.; ! !#8݌ $ Ќ  !  !0 4 0 4!4! 4   4.3UnzipandUntar#!!G!.::% ! !#8! ݌   Ќ    0 4 0 4!4!0 ! !   4.3.1WinZip#!!G!.rr# ! !#9݌ X! Ќ    0 4 0 4!4!0 ! !   4.3.2Othertarandziputilities#@!@!F!.rr8 ! !#10݌ j" Ќ    0 4 0 4!4!0 ! !0< ! !   4.3.2.1DOStarandziputilities#@!@!F!.<<!<!#10݌ ,# Ќ    0 4 0 4!4!0 ! !0< ! !   4.3.2.2UNIXtarandziputilities#@!@!F!.=<!<!#10݌  $ Ќ    0 4 0 4!4!0 ! !0< ! !   4.3.2.3NTtarandziputilities#@!@!F!.ff;<!<!#10݌ `!% Ќ  Vm  Vm0 4    5.ProblemsDownloadingData#@!@!F!.  )4!4!#10Vm݌ "4' Ќ  !  !0 4 0 4!4! 4   5.1FTP#@!@!F!.  ! !#10!݌ #( Ќ  Vm  Vmd0 4    6.ConclusionsandPointsofContact#@!@!F!.14!4!#11Vmd݌ *%z * Ќ     !  1.Introduction q !  2(#. TwodigitalcartographicproductsoftheU.S.GeologicalSurvey(USGS)arevector(DLG)andterrainelevation(DEM)dataintheSpatialDataTransferStandard(SDTS)format.TheUSGS distributesthesedatasetsovertheInternetasameansofpromotingthestandard.TheSDTS *:&1 isarelativelynewformatthathasbeenmandatedforfederaluse.NumeroussoftwarepackagesfromvendorssuchasESRI,IntegraphandERDASareabletoacceptdatainthisformat.  ThisdocumentisadetailedexplanationofproceduresfordownloadingandunpackingUSGSSDTSdata.DLGdatasetswerecreatedbyreformattingdigitallinegraphoptional(DLGO)dataasSDTS.DEMdatasetswerecreatedbyreformattingexistingdatasetstotheSDTSformat.Theseconversionsincludeaddingmetadatatoeachtransfer,butdonotnecessarilyincludeanyupdateorothercontentchangestothespatialdata.Thisdocumentcanbeusedasacompanionto:̄dlgv32Windows95DisplaySoftwareforDLG,DEM,andDRGData(usersmanual,version3.5),or̄dem3dWindows95DisplaySoftwareforDEMData(usersmanual,version2.0b)Theproceduresdescribedheremayalsobebeneficialtousersofothersoftware.See http://mcmcweb.er.usgs.gov/viewers foradditionalinformationaboutdlgv32ordem3d. ^   ,X !  2.OverviewofDLG/SDTSandDEM/SDTSData ,$ Z  U  ! ,X  2.1SDTSOverview $  U  TheSDTSwasdesignedbyagroupofpeoplerepresentinggovernmentagencies,universities,andprivatecompaniesthatallsawarequirementforarobustwayoftransferringearthreferencedspatialdatabetweendissimilarcomputersystemswiththepotentialfornoinformationloss.After12yearsofdiscussion,development,review,andtesting,theresultingSDTSwasapprovedasFederalInformationProcessingStandard(FIPS)173,andnowalsoasFGDCSTD002.CompliancewithSDTS,alsoknownasFIPS173,isnowmandatoryforallfederalagencies.SDTSisatransferstandardthatembracestheideaofselfcontainedtransfers;spatialdata,attributes,georeferencing,adataqualityreport,adatadictionary,andothersupportingmetadataareallincludedinthetransfer.TheSDTSisastandard.Standardsaredocumentsthatspecifyrules;theyareneithersoftwarenordatabases.TheSDTSisastandardfordatatransfer,asopposedtoastandardfordataprocessing.SDTS " doesnotreplaceexistingGeographicInformationSystem(GIS)processingformats.TheSDTSisdesignedspecificallyforspatialdata.Otherstandardsexistforotherkindsofdata(digitalimages,documents,electronicsignals,etc.).TheNationalMappingDivisionoftheUSGSisthemaintenanceagencyforthestandard.PleasevisittheSDTSwebsiteat http://mcmcweb.er.usgs.gov/sdts formoreinformation .  $( )  AsingledocumentoverviewofSDTSisavailableat:  h&!+  4 ftp://sdts.er.usgs.gov/pub/sdts/articles/ascii/overview.doc or , 0'",  4 ftp://sdts.er.usgs.gov/pub/sdts/articles/ps/overview.ps   'H#-  U   2.2MassConversionofUSGSDatatoSDTS ,# U+#  P*%0 In1995theUSGSbeganconvertingdigitalcartographicdataholdingstoSDTS.1:24,000scale(or7.5minute)DEMdatawereconvertedinearly1998.ConversionofotherDEMscaleshavenotyetbeencompleted. The1:2,000,000scaleDLGdatawererevisedin1995andarenowavailableinSDTS.ThisincludescoverageoftheconterminousUnitedStatesforthefollowingcategoriesofdata:hydrography,transportation,boundaries(countynamesareincludedwiththetransfer),UnitedStatesPublicLandsSurveySystem,andmanmadefeatures.All1:100,000scaleDLGfileshavebeenconvertedtoSDTSformat.Thisincludesnationalcoverageofthehydrographyandtransportationoverlays,withpartialcoverageofotherlayers.All1:24,000scaleDLGfileshavebeenconvertedtoSDTSformat.Coveragevariesbetweenoverlaysatthisscale,butnooverlayhascompletecoverage."Allfiles"meansallfilesforwhichDLGdatahavebeenproduced.Coverageof1:24,000and1:100,000scaleDLGdataisnotcomplete.U   2.3SalesandDistributionPolicies 0  U f MostUSGSdataareneitheronlinenorfree.SDTSdataareasignificantexceptiontothispolicy.Otherexceptionsinclude1:100,000scaleDLGOand1:250,000scalenativeformatDEMdata.Production,pricing,anddistributionpoliciesfornativeDLGOandnativeDEMdatahavenotchangedduetotheavailabilityofSDTSdata.Datainnativeformatarestillavailablefromthesamesourcesatthesameprices.Becauseofdataconversionproblems,thereareasmallnumberofdatasetsthatareavailableinnativeformatbutnotavailableinSDTS.AllDEMdatanowofferedinSDTSformatarestillavailableinnativeformatU   2.4SDTSdataorganization 3  U T!  XX  2.4.1DLG/SDTSData o4#XXP4#  *# DLGOdataarederivedfromstandardUSGStopographicquadrangles.ThepackagingofDLGOdatareflectsthis:eachphysicalfilecoversthegeographicareaofsomepartofastandardquadrangle,andcontainsafeaturesetthatapproximatestheinkcolorsofastandardpublishedmap.Similarly,DLG/SDTSdataarederiveddirectlyfromDLGOdata,andreflecttheDLG-Odatapackaging.EachSDTStransferhasthesamegeographiccoverageandsamespatialdatacontentastheDLGOitwasderivedfrom.ThispackagingisnotdictatedbytheSDTS;thestandardwouldallow(forexample)allroadandhydrographydataforacountytobecontainedinonetransfer,butreorganizingthedatathiswaywouldhaverequiredalargeandcostlyproductionoperation,insteadofarelativelysimpledatareformat.AsideeffectisthattheDLG/SDTSdataappearmorefragmentedandcomplexthannecessary.ThisisnotacharacteristicoftheSDTS,butofpolicydecisionsmadewhentheUSGSmassconvertedDLGOdatatoSDTSformat. $,t'3  XX  2.4.2DEM/SDTSData#XX8# 9  DEMdataarederivedfromstandardUSGStopographicquadrangles.ThepackagingofDEMdatareflectsthis:eachphysicalfilecoversthegeographicareaofsomepartofastandardquadrangle,Similarly,DEM/SDTSdataarederiveddirectlyfromDEMdata,andreflecttheDEMdatapackaging.EachSDTSDatatransferhasthesamegeographiccoverageandsamespatialcontentastheoriginalsourceDEM. ,X !  3.SummaryofDataRetrievalProcedures 8; 0    ! ,XDLG/SDTSandDEM/SDTSdataareheldonanftpsite. d  ThebaseaddressforDLG/SDTSdatais ftp://edcftp.cr.usgs.gov/pub/data/DLG  &v  ThebaseaddressforDEM/SDTSdatais ftp://edcftp.cr.usgs.gov/pub/data/DEM >  U   3.1DLG/SDTSData <# U<#  F  TherearethreesubdirectoriesintheDLGFTPsite;oneforeachofthethreedatascales.Thesethreescalesare: 100K holds1:100,000scaledata.ThedirectorycontainsanSDTSmasterdatadictionaryfor b thisscale,areadmefile,and26subdirectories,oneforeachletterofthealphabet.Eachofthesesubdirectoriesholdsthe1:100,000scalequadrangleswhosenamesstartwiththatletter. 2M holds1:2,000,000scaledata.ThedirectorycontainsanSDTSmasterdatadictionaryfor p thisscale,areadmefile,and50subdirectories,oneforeachstate. LARGE_SCALE holds1:24,000scaledata.ThedirectorycontainsanSDTSmasterdata ~ dictionaryforthisscale,areadmefile,and26subdirectories,oneforeachletterofthealphabet.Eachofthesesubdirectoriesholdsthe1:24,000scalequadrangleswhosenamesstartwiththatletter.EachdatasubdirectoryinturnhasseveralmorelevelsofdirectoriesthatreflectDLGoverlays,dataversions,andphysicalpackaging.TheUSGSGeoDatawebpage,at http://edcwww.cr.usgs.gov/doc/edchome/ndcdb/ndcdb.html  V#' providesauserinterfacetotheftpsite.Thewebpageprovidesseveraldifferent"views"ofthedata,includinglistsbystate,byname,andsearchingbygraphicindex.Alloftheseviewseventuallyleadtothelowestleveloftheftpdirectorystructure.̀TheGlobalLandInformationSystem(GLIS),at http://edcwww.cr.usgs.gov/webglis provides &'v", anotherwaytoreachthesedata.GLISprovidesrelativelypowerfuldatasearchtools.AnSDTStransferiscomposedofmultiplefiles.DLG/SDTStransfershavebeencombinedintoonephysicalfilewiththetarutility,andthencompressedusinggzip.Seesection4.3fordetails.U   +'2   3.2DEM/SDTSData D # UD#  TherearefoursubdirectoriesintheDEMFTPsite.Atthistime,only7.5minuteDEMsareintheSDTSformat. 15min containsnodataatthistime.Itwillholddatabasedon2by3arcsecondspacing.  CoverageofoneDEMcorrespondstoa1:63,360scalequadrangle,usedprimarilyforAlaska. 250 holdsdatabasedon3by3arcsecondspacing.Thisdirectoryispopulatedwithdatain  h nativeDEMformat.Itcontainsareadmefile,and26subdirectories,oneforeachletterofthealphabet.Eachofthesesubdirectoriesholdsthe1:250,000scalequadrangleswhosenamesstartwiththatletter. 30min containsnodataatthistime.Itwillhold1:100,000scaledata,alsoknownas2arc 8  second. 7.5minute hasthesamecoverageasthestandardUSGS7.5minutecell.Insomecases,this 4  isnotanexactmatchofthecorrespondingtopographicmap.DEMsnevercontainoveredgedataforsliversoflandjustbeyondthecellboundary.ThisdirectoryispopulatedwithdatainSDTSformat.Itcontainsareadmefileand26subdirectories,oneforeachletterofthealphabet.Eachofthesesubdirectoriesholdsthe1:24,000or1:25,000scalequadrangleswhosenamesstartwiththatletter.TheUSGSGeoDatawebpage,at http://edcwww.cr.usgs.gov/doc/edchome/ndcdb/ndcdb.html J  providesauserinterfacetotheftpsite.Thiswebpageprovidesseveraldifferent"views"ofthe b data,includinglistsbystate,byname,andsearchingbygraphicindex.TheGlobalLandInformationSystem(GLIS),locatedat http://edcwww.cr.usgs.gov/webglis X  providesanotherwaytoreachthesedata.GLISprovidesrelativelypowerfuldatasearchtools.  p Alloftheseviewseventuallyleadtothelowestleveloftheftpdirectorystructure.AnSDTStransferiscomposedofmultiplefiles.DEM/SDTStransfershavebeencombinedintoonephysicalfilewiththetarutility,andthencompressedusinggzip.Seesection4.3fordetails.EachDEMtransfercontainsadatadictionary;thereisnoseparatemasterdatadictionarytobedownloaded. ,X !  4.DetailedInstructionsforRetrievingSDTSData N v#(  ! ,XThissectioncontainsstepbystepinstructionsforretrieving,unpacking,andorganizing $) DLG/SDTSandDEM/SDTSdata.TheConifer,CO1:24,000scalequadrangleisusedasanexampleofDLGdata.TheBigBullMountain,CO7.5minutequadrangleisusedasanexampleofDEMdata.Proceduresfortheotherscalesaresimilar,butvaryslightlybecauseofdifferentproductcharacteristics.Theseexamplesshowhowtofinddatausing FTPviagraphicscapabilitiesontheGeoData webpage.Userswhoknowwhattheyarelookingforandknowhowtouseftpclientsoftware |+&2 maywishtoskiptheseproceduresandgodirectlytotheftpsitedescribedinsection3.Readingsection4.3isstronglyrecommendedbeforedoingthis. U   4.1CreateLocalDirectory Q  UԀ  Createdirectories(orfolders)onyourlocalcomputertoholddownloadedfiles.Forthepurposesoftheseexamples,wewillassumeyouareusingacomputerwiththeWindows95operatingsysteminstalled.Ifyouplantousemultiplequadrangles,itisimportanttoorganizethedatainafilestructurethatwillhelpyoukeeptrackofalldata.Createanadditionalsubdirectoryforeachquadrangle.AnSDTStransfertypicallycontainsmanyfiles.KeepingtransfersseparatebyputtingeachquadrangleinitsowndirectoryisnecessarybecauseofthewayfileswithinaDLG/SDTSorDEM/SDTStransferarenamed.Storingmultiplequadranglesinonedirectorymayresultinfilecollisions,whereonefilemayoverwriteanotherwiththesamenamingconvention.FortheDLG/SDTSexample,createadirectorynamed c:\data\sdts\conifer.  "r  FortheDEM/SDTSexample,createadirectorynamed c:\data\sdts\big_bull  :  U   4.2FindandRetrieveData !V  U 6  XX  4.2.1FindandRetrieveDLG/SDTSData#XXV# V  \ AMasterDataDictionary(MDD)mustbedownloadedforeachscaleofDLGdata(100K,2M,andLargeScale)datayouintendtouse.Detailedinstructionsareincludedinsection4.2.1.2,below.Todownloadaspecificdataset,followtheseprocedures:1.GototheUSGSGeoDatapageat http://edcwww.cr.usgs.gov/doc/edchome/ndcdb/ndcdb.html   2.Scrolldownthepageto LargeScaleDigitalLineGraphs(DLG)SDTSformatonly.  L 3.Sincethenameofthequadrangleisknown,thedatacouldbefoundbyselectingeitherFTP &  via󀀀AlphabeticalListorFTPviaState.However,itiscommontonotknowexact ! quadranglenames:Select FTPviaGraphics .  l# 4.Select Conterminous48states . !% 5.AsimplemapoftheU.S.appears.Clickonthe stateofColorado . 0#' 6.AmapofColoradoappears,with1degreelinesoflatitudeandlongitude.Click nearthe $ ) centerofthe1degreecell immediatelywestofDenverandimmediatelysouthofBoulder . % * Thenextdisplaywillshowapproximately307.5minutequadrangles,centeredonwhereyouclickedyourmouse.7.Clickonthe7.5minutecelllabeled Conifer,CO.  (#. 8.A"list"ofonequadrangleappears.(Otherpathstothispagemayproducelistsofmorequadrangles.)Selectthelinkto Conifer,CO.  *,&1   +&2 Alistofninedirectorieswillthenappear.EachdirectorycorrespondstooneDLGoverlay. Coniferisusedinthisexamplebecauseallnineoverlaysareavailable.Thisisunusualfor1:24,000scaledata;mostquadrangleshavefewerthannineoverlaysfinished.9.Selectthesecondoverlay(inthisexample), hydrography .  10.Select version_1 ,themostrecentversion. B  ThefileD3910530_hy0s.1.sdts.tar.gzcontainstheSDTStransferforthehydrographylayerof   theConifer,COquadrangle.Foranexplanationofthefilenamingconvention,see http://edcftp.cr.usgs.gov/pub/data/DLG/LARGE_SCALE/00README P    11.Selectthefile D3910530_hy0s.1.sdts.tar.gz fordownloading  0  12.Saveittothe c:\data\sdts\conifer folder.Thefilecanberenamed(forexample, j  conifer.tar.gz).Retainingthe.tar.gzextensionsisstronglyrecommended.Somebrowserswillattempttorenamethisfileforyou.Insomecases,thisrenamingcausesproblemsfordecompressionsoftware.Onecommoncaseisarenamefrom*.tar.gzto*_tar.gz,whichconfusestheWinZipdecompressionprogram.Repeatsteps9through12foralloverlaysofinterest.  4.2.1.1DLG/SDTSTransportationOverlay:ASpecialCase b   WhileyoureattheFTPsitegettingdatafortheconifer,COquadrangle,pullupthetransportationsubdirectory,andclickon version_1 .  Z YouwillseethatitcontainsthreeDLG/SDTStransfers:roads(therd0sfile),railroads(therr0s)file),andmiscellaneoustransportation(forairports,pipelines,etc)(themt0sfile).AllDLGO1:24,000scalesalesunitsarepackagedthisway,andthatpackagingwasretainedintheSDTSversionofthedata:threeseparateSDTStransportationtransferswerecreatedforeachquadrangle.Thedataforthesetransfers must bekeptinseparatedirectories.Untaringtwoor  moretransportationtransfersforthesamequadinthesamedirectorywillcausefilecollisionsandlossofdata.Ifyouintendtousemorethanoneofthesethreetransportationlayers,createsubdirectoriesforeachofthem.Forexample,c:\data\sdts\conifer\railroad.Thisstepneednotbedonebeforedownloadingthedata,butmustbedonebeforeunzippinganduntaringthedata(section4.3).In1:100,000and1:2,000,000DLGdata,thethreetransportationoverlaysarecombinedintoonefile,andthereforecompriseonlyoneSDTStransfer.Creationofadditionaltransportationsubdirectoriesisnotnecessaryforthesescales.U  # U)h#  4.2.1.2RetrievetheDLG/SDTSMasterDataDictionary oh  %T * EachSDTStransferisrequiredtohaveadatadictionary,specifictothatparticulartransfersscale.BecausetheDLG/SDTSdatawerecreatedbyreformattingDLGOdata,thesamedatadictionarycanbeusedforalldatasetsofthesamescale.Ratherthanincludethisdictionarywitheachtransfer,onedatadictionaryisstoredforalltransfersatthetopoftheftpdirectorytree.ToretrievetheMDD: +,'3 1.Goto http://edcftp.cr.usgs.gov/doc/edchome/ndcdb/ndcdb.html   2.Scrolldownthepageto LargeScaleDigitalLineGraphs(DLG)SDTSformatonly.  : 3.Clickon singletarfile.   4. Saveittothe c:\data\sdts\conifer folder T  ThisfilemustbeunzippedanduntaredlikeotherSDTSdata.Placementofthedatadictionaryfilesmaybesoftwaredependent.Ifusingdlgv32,thefilesmaybeplacedinanydirectoryonyourharddrive,includingthedirectorythatholdstheotherSDTSdatafiles.IfusingESRIArc/Info,placethedatadictionaryfilesinthemasterdddirectoryasspecifiedbyESRIdocumentation. XX  4.2.2FindandRetrieveDEM/SDTSData m#XXom#  >  1.GototheUSGSGeoDatapageat http://edcwww.cr.usgs.gov/doc/edchome/ndcdb/ndcdb.html    2.Scrolldownthepageto 7.5MinuteDigitalElevationModel(DEM)SDTSformatonly . &v 3.Sincethenameofthequadrangleisknown,thedatawerelookingforcouldbefoundbyselectingeitherFTPviaAlphabeticalListorFTPviaState.Sinceitscommontonotknowexact r quadranglenames,maketheselection FTPviaGraphics . 4 4.AsimplemapoftheU.S.appears.Clickon thestateofColorado.   5.AmapofColoradoappears,with1degreelinesoflatitudeandlongitude.Clickonthe bullet H rightnexttoColoradoSprings .Thenextdisplaywillshowapproximately307.5minute ` quadrangles,centeredonthismouseclick.6.Clickonthe7.5minutecelllabeled BigBullMountain,CO.  \  7.A"list"ofonequadrangleappears.(Otherpathstothispagemayproducelistsofmorequadrangles.)Selectthelinkto BigBullMountain,CO.  # Thefile30.1.1.934296.tar.gzcontainstheSDTStransferforBigBullMountain,CO.Foran 2!% explanationofthefilenamingconvention,see http://edcftp.cr.usgs.gov/pub/data/DEM/7.5min/00README "'  8.Selectthefile 30.1.1.934296.tar.gz fordownloading. F$) 9.Saveittothe c:\data\sdts\big_bullfolder .Thefilecanberenamed(forexample, % !+ bigbull.tar.gz).Retainingthe.tar.gzextensionsisstronglyrecommended.Somebrowserswillattempttorenamethisfileforyou.Insomecases,thisrenamingcausesproblemsfordecompressionsoftware.Onecommoncaseisarenamefrom*.tar.gzto*_tar.gz,whichconfusestheWinZipdecompressionprogram. U   4.3UnzipandUntar u # Uu# $+t&2 TheDLG/SDTSandDEM/SDTSdataweredesignedin1994,beforethereleaseofWindows95 andbeforemostPCswerepowerfulenoughtouseGISdata.Thedataweredesignedforthescientificcomputersofthetime,whichweremostlyUNIXworkstations.ThefilesineachSDTStransferwerecombinedintoonefilewiththeUNIXtarutility,andthiscombinedfilewasthencompressedusingthegnuzip(gzip)utility.ThistechniqueforcombiningandcompressingfilesiscommonontheUNIXoperatingsystem.TarandgziparenotascommoninthePCworld,butavarietyoffreeware,shareware,andcommercialimplementationsoftheseutilitiesexistforallPCoperatingsystems.U   XX U4.3.1WinZip#U XX&y# y  U    OneofthemostcommonPCcompressionprogramsisthesharewareprogramWinZip̀( http://www.winzip.com ).WinZipwillunzipanduntarDLG/SDTSandDEM/SDTSfilesif >  properproceduresarefollowed.TheseinstructionsareforWinZip6.3forWindows95,usingtheWinZipClassicinterface(asopposedtotheWizard;thisisauserselectableoptioninWinZip).Ensurethatthefilehasanameoftheform*.tar.gzNOT*_tar.gz ^  1.StartWinZip2.Fromthetoolbar,select Options f  3 . Select configuration .  4.Thereisacheckboxlabeled TARfilesmartCR/LFtranslation.Ensurethatthisboxisnot 0 checked. B 5.Select OK toexitconfiguration. v 6.Select Open fromthetoolbar.Apopupwindowappears. P 7.Inthe"Typesoffiles"subwindow,select All Archives .   8.Navigatetothelocaldirectoryyoucreatedearlier(c:\data\sdts\coniferforDLG/SDTSdataorc:\data\sdts\big_bullforDEM/SDTSdata).AlistofthefilesdownloadedfromtheUSGSGeoDatasiteshouldbevisible.Selectoneofthesefilesandclick Open .  $ 9.Awindowappearswiththemessage Archivecontainsonefile8.decompressittoatemporaryfolderandopenit?Select Yes . "4' 10.Alistof.ddffileswillappear.ThesearethefilescontainedintheSDTStransfer.Toselectallfilesinthetransfer, clickonthefirstfile,thenshiftclickonthelastfile . 0% * 11.Select Extract fromthetoolbar. & ", 12.Apopupwindowlabeled"Extract"appears.Enter,ornavigateto,thepathanddirectorythatyouwanttoplacethedatainto.Theextractedfilesarestoredinthesamedirectoryasthecompressedfiles,soenter(ornavigateto)thelocaldirectoryyoucreatedearlier(c:\data\sdts\coniferforDLG/SDTSdataorc:\data\sdts\big_bullforDEM/SDTSdata),thenclickthe Extract button.Thiswillunzipanduntarthefiles. L+&2  ,d'3 NOTE:Donotrenamefilesextractedfromthetarfile.ThefilesinanSDTStransferarereferencedbynameinotherfilesofthetransfer.Renaming.ddffileswillbreaktheserelationships.U  XX U  4.3.2Othertarandziputilities #U XX#  U  TarandgzipforDOS,UNIX,andNToperatingsystemsareavailableintheGNUutilitiesfromtheFreeSoftwareFoundation.Softwarelocationsforeachoperatingsystemlistedbelow.  4.3.2.1DOStarandziputilities      Copiesofthesecanberetrievedfrom 4 ftp://ftpmcmc.er.usgs.gov/pub/sdts/software/tools/tar.exe   6    4 ftp://ftpmcmc.er.usgs.gov/pub/sdts/software/tools/gunzip.exe ThesemustberuninaDOSwindow,usingthefollowingsyntax: n  Ѐ0 4 toUnzip: \gunzip0 4!4!  4 toUntar: 0 < \tarxvf <!<! whereisthepathtothedirectorythatcontainsthegunzipandtarexecutables.  4.3.2.2UNIXtarandziputilities    Copiesofthesecanberetrievedfrom 4 ftp://ftpmcmc.er.usgs.gov/pub/sdts/software/tools/tar   4  4 ftp://ftpmcmc.er.usgs.gov/pub/sdts/software/tools/gunzip  4.3.2.23NTtarandziputilities Ĉ Copiesofthesecanberetrievedfrom T  4 ftp://ftpmcmc.er.usgs.gov/pub/sdts/software/tools/winnt/tar.exe L  f  4 ftp://ftpmcmc.er.usgs.gov/pub/sdts/software/tools/winnt/gunzip.exe  ,X !  5.ProblemsDownloadingData E# ! ,X&# D   # TheavailabilityoffreeSDTSdatahascausedsevereoverloadsontheGeoDataserverandrelativelyfrequentperiodsofdowntime.Untilhardwareupgradescanbeapplied,wecanonlysuggesttryingat offtimesoftheday.Unfortunately,theUSGSdoesnothavethestafftoprovidetutorialsupportforcommercialsoftware.Ifyoucannotaccessthesedatathroughyourbrowser,werecommendeither:̄studyingyoursoftwaredocumentationforanonymousftpconfigurationprocedures,or̄usinganftputilityinsteadofabrowser. XX  5.1FTP #XX#  D)$/ Differentbrandsandversionsofwebbrowsersimplementanonymousftpdifferently.TheUSGShastestedanumberofbrowsersontheftpsitedescribedinthispaperandbelievesthatthedatacanbeaccessedthroughmostbrowsers.However,thedefaultbrowserconfigurationsare +'2 notalwayscorrectforanonymousftpaccess,andinsomecaseschangingthoseconfigurationsissomewhatdifficult.Somesiteswhereftputilitiescanbedownloadedandpurchasedare: 4 http://www.cuteftp.com    4 http://www.ftpx.com   Asanalternative,usersofWin95orWinNTcanftpdatausingtheRunfunctionontheStartMenu:Type ftp://edcftp.cr.usgs.gov andselect OK.   b  Login: 4 anonymous  *  Password:youremailaddressintheform name@domain    Fromthere,makethefollowingchoices: pub/data/DEM/7.5min/B/big_bull_mountain_CO (this &v  willgetyoutotheDEM/SDTSdatasetweusedinourexampleearlier)Atthispointtheuserisabletonavigatetothelayertobedownloaded.Tochangethedatatransfertypetobinary,typebinary.Tospecifywhichdirectorythedataistobedownloadedto,typelcdnameofdirectory.Todownloadthedata,typegetnameoffile.Toexit,typequit. ,X !  6.ConclusionsandPointsofContact  ! ,X D DLG/SDTSandDEM/SDTSdataarerelativelynew.Thedesignofthesedatacouldandwillbeimprovedforfuturedataproduction.Thedataareusableintheircurrentformifproperproceduresarefollowedandappropriatesoftwareisavailable.̀FormoreinformationaboutSDTS,see http://mcmcweb.er.usgs.gov/sdts .Tomake   commentsoraskspecificquestionsaboutSDTSortheUSGSimplementationofDLG/SDTS,sendmailto sdts@usgs.gov  Z"  Forinformationaboutdlgv32,USGSfreewareforWindows95thatwilldisplayDLG/SDTSdata,see http://mcmcweb.er.usgs.gov/viewers . "h&   #( Ѐ#!#