Great Basin GIS

Nevada-Utah Statewide GIS Datasets

Updated 7 February 2024

Nevada Geology:

Several versions of the Nevada 500,000 scale geologic map (Stewart and Carlson, 1978) are available:

Basic: From the USGS GIS dataset with many additional attributes added.  The rock and fault topology of this dataset does not match.

As Published:  Heavily modified from the source GIS data set. Rock and fault topology consistent. Thousands of linework edits have been made to remove "automatic vectorizing" artifacts at fault-contact intersections. Thus the map can be enlarged somewhat without looking too ugly, unlike the original source GIS and Basic version above. A few edits to have been made to update the maps based on new mapping, age-dates etc.

Enhanced:  Has extensive age-date and mapping updates, in addition to all that is in the As Published version.

One version of the "New" Nevada 250,000 scale geologic map (Crafford, 2007) is available:

Basic: From the USGS GIS dataset with many additional attributes added to the rock table. A lengthy legend text file is included, which is linked to the rock table using the same tool as in the detailed quad maps. There are few attributes to the fault and contact tables. The rock and fault topology of this dataset does not match in all locations (especially at county map boundaries), and there are remnant contacts within units that were not removed when map units were combined in the USGS map preparation.

Utah Geology:

Enhanced:  From Utah Geological Survey Map 179DM. Attributes such as Formation name, lithology, environment of deposition, isotopic age were added based on the various stratigraphic columns covering different geologic provinces.

Nevada Mineral Occurrences:

Updated August 2023

 

This geographic-oriented GIS database is intended to contain all mines, deposits and described occurrences in the state of Nevada. To my knowledge, this is the best, most complete, and easiest to use mineral occurrence database covering this area. The database covers all mineral products, with the exception of geothermal, petroleum, and sand/gravel (several dozen commercial sand and gravel operations in major markets are included). Gemstones, mineral specimens, and semi-precious stones are included only as encountered, and are highly incomplete at present.

 

Geographic coverage of the state is complete, including the various types of restricted-access areas. The database contains both historical and recent occurrences and discoveries.

 

This database is constructed with the philosophy that all locations will be entered, regardless of how close together they are. Individual, closely spaced mines or deposits are not grouped by their location. This allows more of the local trends, clusters and alignments of ore bodies to be seen.

 

At of 11/20/2019 there were 14,783 entries, of which 7684 contain Au, 6545 contain Ag, 4327 contain Cu, 3869 contain Pb, 2467 contain Zn, 1539 contain Mo, 246 contain Ni, 813 contain U, 940 contain W, 1605 contain Hg, 1812 contain barite or elevated Ba, 315 contain fluorspar, and 2795 contain Sb. There are 3301 records that have other commodities (industrial minerals, iron and rarer elements) listed and 4401 records that contain trace elements not listed above. There are 648 entries at altered areas, quartz veins, etc. with no commodity listed.

 

This database can be used to locate, select, graph, and map Nevada mineral occurrences by many different criteria, including deposit types, commodities, and sizes. It is also a useful source of reference material for more detailed descriptions of the occurrences. It can also be used to check for company activity. This is not a current news database, but rather a historical geologically-oriented database. However, new properties or discoveries are included as encountered.

 

This database includes information from sources that are known to be in part unreliable, incomplete, inaccurate and/or incorrect. Users should verify all information to determine its suitability for their intended use. Accordingly, all numeric data should be considered approximations, especially such data as discovery date, status date, location accuracy and the size and grade of commodities.

 

INCLUSION CRITERIA:

 

To be included, an occurrence must contain at least two of the following 3 criteria:

 

  1. elevated concentrations of economic elements or commodities, or geologic features that suggest this (e.g. quartz veins, gossans, altered zones).
  2. a description in the literature, or personal field notes.
  3. physical workings or drilling/sampling activity.

 

Based on these criteria, conceptual-only targets and undocumented mine and prospect symbols from legacy topographic maps are generally not included. In some cases, exploration programs evidenced by drilling (especially for gold) have no documentation that any commodity concentration was encountered. In some such cases, a notation was placed in the Remarks field that the commodity content was uncertain.

 

The inclusion criteria allow access tunnels to distant orebodies that have no indication of mineralization near the entrance, but are described in the literature. These are included in the database as Type = "mine entrance". For such entries, some notes are included but no commodities. Often these have large conspicuous dumps and would be confusing if not included.

 

DATABASE TABLES:

 

The database consists of three tables and a text document. The Main Table consists of a single flat file of GIS points. This approach was taken to make the table easy to use for persons not conversant with more complex relational database systems. The second table contains GIS polygons and polylines representing mineral outlines, footprints, grade contours and vein traces etc. for a limited number of occurrences and with a limited number of data fields. A third non-mappable table contains approximately 2800 full bibliographic references linked to the entries in the main table. A text document (this one) contains explanations of the various philosophies, abbreviations, sources, and other aspects of the database that could not be included in the database table itself.

 

The main table contains both text and numeric fields referencing the type of entry, location accuracy, name, alternate names, district names, geology of the deposit and host rock, age of the deposit, physical size and orientation, discovery year, exploration/development/mining/abandonment status, separate numeric size/grade field pairs for Au, Ag, Cu, Pb, Zn, Mo, Ni, U, W, Hg, barite, fluorspar, and Sb, Fields for other commodities, minor elements, sources of data, sources of location, and remarks fields for geology, resources, production, companies, and miscellaneous notes. Of course, in many entries, no data was found to place in a number of the fields.

 

A great deal of effort was made to locate the entries accurately. The combination of statewide coverage 1:24,000 scale topographic maps, 1m pixel orthophotos of several recent dates, BLM LR2000 database system, mineral survey and mineral connection plats, exploration company websites, Canadian instrument 43101 technical reports, along with careful inspection of text descriptions and individual, small scale maps in USGS and 1orts have enabled the location accuracy of many entries to be improved over an order of magnitude from the 1:250,000 scale NBMG county report plates. As of November 20, 2019, 10,216 entries are estimated to be located to 100 m or better.

 

In most cases, individual workings, mines, or prospects are located, with some exceptions in major districts. The major ore bodies of the Comstock are so well described, that they were listed individually, and data from different company mines were combined to form one entry for each orebody. In other cases (Reese River District, Goldfield, Tonopah, Pioche) this was not possible, at least for now, and individual workings are listed separately.

 

Some prospects shown on the NBMG County Bulletin plates have not been included if no commodity was listed, or it appeared from other sources that they were probably nonexistent, were claim discovery pits of the 1960s era or were sand/gravel pits, and thus did not meet the above inclusion criteria. Many of these were in Esmeralda and Lyon Counties. In the Lander Co. report there were numerous mines that were listed in the various tables, but only approximate locations were given. These were grouped at the same location, more or less centrally located within the uncertainty area of their location information (see Battle Mt, Reese River, and Pioche districts). Some of these grouped locations have been improved using other sources.

 

SOURCES:

 

The sources of information for both data and location are nearly all public:

 

1) The current set of NBMG County mineral bulletins and reports, including both text and plates.

2) The current set of NBMG and USGS statewide commodity publications.

3) County-wide, state-wide, or multi-district, and district-scale publications and open-files.

4) Mineral assessment reports for Wilderness Study and BLM resource areas, ACEC areas, etc.

5) Symposium Proceedings and Guidebook Compendiums, and some guidebook articles.

6) NBMG and NV DOM yearly reports and archived documents.

7) Newly encountered papers, maps, guidebooks, books, etc.

8) Southern Pacific Company Report and 24K-series maps.

9) Company Web Sites, annual reports, presentations and technical reports.

10) Notes from various GSN, NWMA-AEMA and other symposiums and field trips.

11) Other sources

Utah Mineral Occurrences:

This is a GIS database which is intended to contain all mines, deposits and described occurrences in the state of Utah.  The database covers all mineral products, with the exception of liquid and gaseous petroleum, helium, carbon dioxide and geothermal energy. This is an historical geological-exploration-oriented database, not a current news database.  However, new properties or discoveries are included as encountered. At present coal occurrences are incompletely represented.  Gemstones, mineral specimens, and semi-precious stones are included only as encountered, and are incomplete at present.

This database can be used to locate, select, graph, and map Utah mineral occurrences by many different criteria, including geologic deposit types, commodities, company names, and size.  It is also a useful source of reference material for more detailed descriptions of the occurrences.  It can also be used as context to check for activity in an area of interest.

All or portions of the database can be licensed. Portions to be licensed can be selected by any simple query; for example: only gold occurrences, or only a specific geographic area.

The database consists of three flat files.  Highly attributed mineral points, minimally attributed outlines, and non-mappable bibliographic references. This approach was taken to make the table easy to use for persons not conversant with more complex relational database systems.  A pdf document contains explanations of the various philosophies, abbreviations, and other aspects of the database that could not be included in the database table itself.

The database started with a download of Utah Geologic Survey's Utah Mineral Occurrence System (UMOS) in 2015, after an update by the Utah Geological Survey. All records were initially retained, but many fields were consolidated and non-essential and repetitive text data were deleted, including quadrangle names and much un-interpretable or unclear information. Many descriptive fields were excessively wordy and repetitive and were reworded for compactness and corrected for spelling. Full reference citations were removed to a separate table.  Following this treatment, 351 publications and websites were carefully reviewed for additional data and verification. The sources of information for both data and location are all public.

The main table contains 9169 entries, of which 1449 contain Au, 1786 contain Ag, 1900 contain Cu, 1412 contain Pb, 864 contain Zn, 278 contain Mo, 10 contain Ni, 1696 contain U, 218 contain W, 126 contain Hg, 270 contain barite or elevated Ba, 300 contain fluorspar, 292 contain Sb, 93 contain coal, and 203 contain various forms of solid petroleum.  There are 5177 records that have other commodities (industrial minerals, iron and rarer elements) listed and 855 records that contain trace elements not listed above. 1849 entries are borrow pits for gravel.

The database started with a download of the Utah Mineral Occurrence System (UMOS) in 2015, after an update by the Utah Geological Survey.   All records were initially retained, but many fields were consolidated and non-essential and repetitive text data were deleted.  Deleted data includes quadrangle names and much un-interpretable or unclear information. Many descriptive fields were excessively wordy and repetitive and were reworded for compactness and corrected for spelling.  Full reference citations were removed to a separate table.  Following this treatment, 351 publications were carefully reviewed for additional data and verification.

To be included or retained from UMOS, an occurrence must contain at least two of the following 3 criteria:

  1. elevated concentrations of economic elements or commodities in rock or soil, or geologic features that suggest this (e.g. quartz veins, altered zones).
  2. a description in the public domain.
  3. physical workings or drilling/sampling activity.

Nearly all the entries downloaded from the UGS Mineral occurrence system meet all 3 of these inclusion criteria.  However further information may cause some to be deleted in the future, some to be split into several entries, and others to be added.

Based on these criteria, purely conceptual exploration targets and some workings without any geologic description or elevated commodity are not included.  In some cases, exploration programs evidenced by drilling (especially for gold) have no documentation that any commodity concentration was encountered, or that the commodity reported was suspect.  In some such cases, a notation was placed in the Remarks field that the commodity content was uncertain or unconfirmed.  In most cases, stream sediment anomalies were not utilized.

UMOS borrow pits were retained, but gravel deposits without workings were removed.  UMOS oil/gas wells and geothermal wells were also removed. The UMOS database contained only a few coal occurrences.  Coal mines are being added as they are encountered, but are not a priority.

The inclusion criteria allow access tunnel entrances to distant orebodies that have no indication of mineralization near the entrance, but are described in the literature.  These are included in the database as Type = "mine entrance".  Typically, some notes are included but no commodities.

The Outline table contains lines and polygons representing outlines of 1036 major and minor deposits and pit outlines, with 8 fields containing type, name, major commodities, estimated accuracy, date, and source

The References table contains a total of 1582 references from UMOS and elsewhere as full bibliographic citations.

A great deal of effort was made to locate the entries accurately.  The combination of statewide coverage 1:24,000 scale topographic maps, 1m pixel orthophotos of several dates, BLM LR2000 database system, mineral survey and mineral connection plats, exploration company websites, Canadian instrument 43-101 technical reports, along with careful inspection of text descriptions and individual, small scale maps in USGS and UGS reports have enabled the location accuracy of many entries to be improved over the UMOS download. 6143 entries are estimated to be located to 100 m or better(more information on www.greatbasingis.com).

Other Geological databases available:
(Nevada only, unless otherwise noted)

Age Dates: USGS Isotopic Age dates, updated from other sources, and accuratized in areas covered by the detailed geological map set

Fossils: Fossil information from various sources, mostly in areas covered by the detailed geological map set

Geophysics:

Gravity: Color shaded relief images, with 2 mgal vector contour lines.  From USGS dataset DDS-42.  This is a regional set, useful at township to statewide scales only.

Magnetics:  Color shaded relief image, with 100 nT vector contour lines.  From USGS downloaded dataset.  This is a regional set, useful at township to statewide scales only.

Geochemistry:

Trace-Element Samples:  A database of more than 158,000 rock, soil, stream-sediment, and drill cutting analyses in Nevada is available. Includes more than 96,000 gold analyses including 66,000 with low (<=50 ppb) detection limit and 48,000 lithium analyses. Data from various Nevada Bureau of Mines and Geology and USGS publications and all the trace-element data from the USGS National Geochemical Database, as well as the original NURE and newly re-analyzed NURE samples. Also data from various USGS, NBMG, and USBM publications. Poorly located samples are quantitatively identified.

Geography (100,000 scale):

Several GIS geography datasets are available. Others can be constructed as needed

Topographic contours: 100,000 scale contours from the USGS Topo maps.
(also available for Utah)

Shaded Relief images: Several images at different resolutions are available.
(also available for Utah)

Hydrography:  100,000 and 1:24,000 scale water bodies and water lines.

Cadastral(PLSS):  100,000 scale and 24,000 scale (GCDB) Township/Range/Sections. Many corrections have been made from the 100,000 scale BLM data set.
(also available for Utah, but without corrections)

Culture (100,000 scale):

Roads: Heavily edited and updated from 100K SDTS source and Tiger Line data.

RailRoads:  Heavily edited and updated from 100K SDTS source, Edited to approximately 1:24,000 scale. Includes many abandoned and dismantled lines.

Power: Electric power lines and other electricity infrastructure. Heavily augmented using 24,000 scale topo maps and field notes.

Other Culture: Fiber-Optic lines, natural gas pipelines, etc. Heavily augmented using 24,000 scale topo maps and field notes.