Theme: Geologic Map from USGS Branch of Alaska Geology
Data Theme Name:  GEOLOGY
Coverage Pathname/Name(s):  /fsfiles/ref/library/gis/chugach/geology
Coverage Type:  Polygon
Coverage Geographic Extent and Projection:  Chugach NF (Forest-wide); UTM Zone 6, NAD27
Source Media/Scale: paper map 
Manuscript Media/Scale: 1:250,000
Date of Source Data:  1985
Date of most recent update:  03/11/97
Source Agency/Organization:  USGS Branch of Alaska Geology
Digitization Method:  Chugach NF staff using ARC/INFO
Cell Size or Minimum Mapping Unit:
Last Update/Maintenance Schedule:  
Known Problems, Technical Limitations, or Constraints (Accuracy):
Remarks: Digitized from the Geologic Map of the Chugach National Forest, AK prepared by Steven W Nelson, JA Dumoulin, & Marti L Miller, 1985. 

                                       <><><><>  Data File and Item Definitions  <><><><>
Theme       File Description           Item           Re- BEG WI O- TY DE ALT     Item Description
Name        ---------------            -----          DEF COL DE WI PE CI Name    ----------------
GEOLOGY     Geologic Map               AREA                1   8 18  F  5         Polygon Area in Square Meters
            Polygons                   PERIMETER           9   8 18  F  5         Distance Around the Polygon in Meters
                                       GEOLOGY#           17   4  5  B  0         Coverage Feature Number - System Generated
            Page 1 of 3                GEOLOGY-ID         21   4  5  B  0         Coverage Feature ID - System Generated
                                    ============ THEME SPECIFIC INFORMATION FOLLOWS ============
                                       GEO-CODE           25   4  4  I  - CODE    Geologic Feature Code 
	                                                                              Valid Codes
	                                                                               100 = Surficial deposits, undifferentiated
	                                                                               101 = Ice fields or Glaciers
	                                                                               102 = Water contacts (Lakes and Ocean)
	                                                                               220 = Yakataga Formation (Miocene)
	                                                                               230 = Redwood Formation (Miocene and Oligocene?)
	                                                                               235 = Sedimentary rocks, undivided Poul Creek 
	                                                                                     Formation (Miocene, Oligocene, and Eocene) 
	                                                                               240 = Tokun Formation (Oligocene and Eocene)
	                                                                               250 = Kulthieth Formation (Eocene)
	                                                                               255 = Stillwater Formation (Eocene)
	                                                                               270 = Conglomerate, Orca Group (Eocene? and Paleocene)
	                                                                               271 = Sedimentary rocks undivided, Orca Group 
	                                                                                     (Eocene? and Paleocene) 
	                                                                               272 = Tuffaceous sedimentary rocks, Orca Group
	                                                                                     (Eocene? and Paleocene) 
	                                                                               320 = Volcanic rocks, undivided, Poul Creek Formation
	                                                                                     (Miocene, Oligocene, and Eocene) 
	                                                                               330 = Pillow basalt, Orca Group (Eocene? and Paleocene)
	                                                                               331 = Pillow basalt and sedimentary rocks, Orca Group
	                                                                                     (Eocene? and Paleocene) 
	                                                                               332 = Interbedded sedimentary and mafic volcanic rocks,
	                                                                                     Orca Group (Eocene? and Paleocene) 
	                                                                               333 = Volcanic rocks, undivided, Orca Group
	                                                                                     (Eocene? and Paleocene) 
	                                                                               334 = Sheeted dikes, Orca Group (Eocene? and Paleocene)
	                                                                               405 = Dacite of Cape Saint Elias (Miocene)
	                                                                               420 = Granite and qranodiorite (Oligocene)
	                                                                               421 = Gabbro and diorite (Oligocene)
	                                                                               422 = Miners Bay pluton (Oligocene)
	                                                                               423 = Mafic plugs (Oligocene)
	                                                                               440 = Granite granodiorite (Eocene)
                                                                                     455 = Felsic dikes (Eocene? and Paleocene?) 

                                        <><><><>  Data File and Item Definitions  <><><><>

Theme       File Description           Item           Re- BEG WI O- TY DE ALT     Item Description
Name        ---------------            -----          DEF COL DE WI PE CI Name    ----------------

GEOLOGY     Geologic Map                                                              470 = Gabbro, Orca Group (Eocene? and Paleocene)
            Polygons                                                                  471 = Ultramafic rocks, Orca Group
	                                                                                     (Eocene? and Paleocene)
	                                                                                510 = Sedimentary rocks, undivided, Valdez Group
            Page 2 of 3	                                                              553 = Ultamafic rocks, Valdez Group
	                                                                                554 = Interbedded volcanic and sedimentary rocks,
	                                                                                      Valdez Group
	                                                                                610 = Paragneiss, Valdez Group
	                                                                                611 = Greenstone, Valdez Group
	                                                                                650 = McHugh Complex melange
                                       GEO-TYPE           29   8 8 C  - TYPE    Geologic Feature Type 
	                                                                               Valid Codes
	                                                                                Fresh = Fresh water (lakes)
	                                                                                Glacier = Ice fields or Glaciers
	                                                                                Km = McHugh Complex melange
	                                                                                Kvg = Paragneiss, Valdez Group
	                                                                                Kvgr = Greenstone, Valdez Group
	                                                                                Kvs = Sedimentary rocks, undivided, Valdez Group
	                                                                                Kvu = Ultamafic rocks, Valdez Group
	                                                                                Kvvs = Interbedded volcanic and sedimentary rocks
	                                                                                       Valdez Group
	                                                                                Qu = Surficial deposits, undifferentiated
	                                                                                Salt = Salt water (ocean)
	                                                                                Td = Dacite of Cape Saint Elias (Miocene)
	                                                                                Tfd = Felsic dikes (Eocene? and Paleocene)
	                                                                                Tg = Granite and qranodiorite (Oligocene)
	                                                                                Tgd = Gabbro and diorite (Oligocene)
	                                                                                Tgg = Granite granodiorite (Eocene)
	                                                                                Tk = Kulthieth Formation (Eocene)
	                                                                                Tm = Mafic plugs (Oligocene?)
	                                                                                Tmb = Miners Bay pluton (Oligocene)
	                                                                                Toc = Conglomerate, Orca Group (Eocene? and Paleocene)
	                                                                                Tod = Sheeted dikes, Orca Group (Eocene? and Paleocene)
	                                                                                Togb = Gabbro, Orca Group (Eocene? and Paleocene)
	                                                                                Top = Pillow basalt, Orca Group (Eocene? and Paleocene)
	                                                                                Tops = Pillow basalt and sedimentary rocks, Orca Group
	                                                                                       (Eocene? and Paleocene)
	                                                                                Tos = Sedimentary rocks undivided, Orca Group
	                                                                                      (Eocene? and Paleocene) 
	                                                                                Tosv = Interbedded sedimentary and mafic volcanic 
	                                                                                       rocks, Orca Group (Eocene? and Paleocene)
	                                                                                Tots = Tuffaceous sedimentary rocks, Orca Group
	                                                                                       (Eocene? and Paleocene)  
	                                                                                Tou = Ultramafic rocks, Orca Group
	                                                                                      (Eocene? and Paleocene)   
	                                                                                Tov = Volcanic rocks, undivided, Orca Group
	                                                                                      (Eocene? and Paleocene)  
	                                                                                Tps = Sedimentary rocks, undivided, Poul Creek 
	                                                                                      Formation (Miocene, Oligocene, and Eocene)
	                                                                                Tpv = Volcanic rocks, undivided, Poul Creek Formation
	                                                                                      (Miocene, Oligocene, and Eocene) 
	                                                                                Tr = Redwood Formation (Miocene and Oligocene?)
	                                                                                Ts = Stillwater Formation (Eocene) 
	                                                                                Tt = Tokun Formation (Oligocene and Eocene)
                                                                                      Ty = Yakataga Formation (Miocene) 

                                        <><><><>  Data File and Item Definitions  <><><><>

Theme       File Description           Item           Re- BEG WI O- TY DE ALT     Item Description
Name        ---------------            -----          DEF COL DE WI PE CI Name    ----------------

GEOLOGY     Geologic Map               FNODE#              1   4  5  B  0         The Arcs's From-Node ID
            Arcs                       TNODE#              5   4  5  B  0         The Arc's To-Node ID
                                       LPOLY#              9   4  5  B  0         The Poly-ID on the Left Side of Arc
            Page 3 of 3                RPOLY#             13   4  5  B  0         The Poly-ID on the Right Side of Arc
                                       LENGTH             17   8 18  F  5         Length of the Arc in Meters
                                       GEOLOGY#           25   4  5  B  0         Coverage Feature Number - System Generated
                                       GEOLOGY-ID         29   4  5  B  0         Coverage Feature ID - System Generated
                                    ============ THEME SPECIFIC INFORMATION FOLLOWS ============
                                       ARC-CODE           33   3  3  I  - AC      Geologic arc code
	                                                                               Valid Codes
	                                                                                 1 = Stratigraphic contact, certain
	                                                                                 2 = Stratigraphic contact, approximate
	                                                                                 4 = Normal fault, certain
	                                                                                 5 = Normal fault, approximate
                                                                                	   7 = Shoreline or riverbank 
	                                                                                10 = Thrust fault, certain
	                                                                                11 = Thrust fault, approximate
	                                                                                15 = Ice contact (glacier limit)
	                                                                                51 = Concealed contact
	                                                                                52 = Concealed fault
	                                                                                53 = Concealed thrust fault
	                                                                                93 = Lineament
	                                                                                99 = Bounding line(neatline) of coverage