Generalized Thermal Maturity Map of Alaska

Online link https://geo-nsdi.er.usgs.gov/metadata/map-i/2494/metadata.faq.html
Description Alaska is a complex amalgamation of tectonic blocks with diverse histories. Sedimentary basins that are formed on these blocks both before amalgamation and as a result of collisions between them record the tectonic history of this complex region. Therma
Originators Johnsson, Mark J.; Johnson, Mark J.; Howell, David G.; Evans, Kevin R.; and Marshall, Heather A.
Publication U.S. Geological Survey Miscellaneous Investigations Series Map I-2494

Related topics

States or counties

AKCANBORDER

Coverage contains a single route in two sections that define the United States-Canadian border.

Label Definition
LTYPE Line Type

BASE.AAT

Coverage contains a base map of Alaska produced by vectorizing a scanned image. Lines define coastline, streams, lakes, and bathymetry. Though cleaned up, it contains very small scanning artifacts that are not resolvable at 1:2,500,000, the intended scale of map.

Label Definition
LTYPE Line Type

CONTOURS.AAT

Coverage contains arcs defining contours on the U/M1 map-unit boundary in areas where sufficient well control exists to define that boundary (Colville Basin and Cook Inlet Basin).

Label Definition
LTYPE Line Type

GRATICULE.AAT

Coverage contains arcs defining latitude-longitude grid lines over map. Many arc segments are needed to make these lines smooth curves.

Label Definition
LTYPE Line type

MAIN.PAT

Principal coverage containing all geologic features (contacts, faults), physiographic features (glaciers, lakes) and thermal-maturity units.

Label Definition
PTYPE Polygon Type
LTYPE Line type

OUTCROPS.PAT

A coverage containing points corresponding to all outcrop sample localities.

Label Definition
CAI Real number giving conodont color-alteration-index value at this locality
VR Real number giving vitrinite-reflectance value at this locality
UNIT Integer value used to define thermal-maturity map unit for this locality
CMDS Character string; a flag used to define continental margin dredge samples. Assigned a null string for all localities except continental margin dredge samples; these are assigned a CMDS value corresponding to map unit for VR or CAI value; used to choose appropriate color of marker symbol in the plot.aml.

TEXT

Coverage contains all of map annotation, including names of water features, political and town names, map-unit tags, geologic-feature names, contour labels, and descriptions of thermal-maturity data from selected wells. Contains leaders as arcs.

Label Definition
LTYPE Line type

TOWNS.PAT

Coverage contains points showing locations of towns. Database category "PTTYPE" defines three size classes, so that towns of different sizes can be plotted with different symbols.

Label Definition
PTTYPE Character string giving town size, used in plotting different size towns with different symbols. Takes on values small, medium, and large.

WELLS1.PAT

A coverage containing points corresponding to selected wells for which thermal-maturity data were used to constrain contours on U/M1 map-unit boundary surface in the Colville Basin and Cook Inlet Basin.

Label Definition
WELLNAME Character string giving name of well
SURF Vitrinite-reflectance value at the ground surface, extrapolated from subsurface data.

WELLS2.PAT

A coverage containing points corresponding to selected wells for which descriptions of thermal maturity data are provided as callouts in the text coverage.

Label Definition
WELLNAME Character string giving name of well
SURF Vitrinite-reflectance value at the ground surface, extrapolated from subsurface data.