The USGS Mineral Resource Surveys Program has since 1989 used contract services to produce digital versions of published and unpublished (manuscript) geologic maps at a variety of scales. For each map, the contractor is required to adhere to specifications that I developed (attachments A and B).
In each case, the contractor is supplied with the original publication separates or manuscript map. In some cases, the geology is separated from the base map information. In other cases, the geologic lines and base map features are contained on a single sheet; this increases the cost of map digitization.
Provided that scale-stable materials are available for scanning, the contractor is required to precisely register the digital map output to the original map. The contractor delivers Arc/Info export files with fully attributed coverages (according to Attachments, provided below). The attributes for all polygons, lines, and points are incorporated into the PATs and AATs of the coverages created. The contractor is requested to make proof plots of the map for us to check. In some cases, this is not possible due to the size of the map and plotting limitations of the contractor. If the contractor cannot plot the map, then I do so (using an HP650 plotter and mylar, not paper) to compare with the scanned materials.
The agreements state that upon delivery of map files and proofs, we must within four weeks examine the deliverables and accept or reject them. Proofing involves the following steps:
- verification that the proof plot exactly matches the source
- verification that all lines and points were digitized, and
- verification that all features were properly attributed.
The contractor has never failed to meet all of these tests. The contractor is to misattribute no more than 10 percent of the features; but they have never approached this level of error. Typically, no contractor errors in positioning or attributing are found. The more significant problem is attribution of tiny polygons that cannot be identified, even by a geologist familiar with the area.
Example costs for contract digitizing and production of attributed Arc/Info coverages is shown below.
|
Map |
Scale |
Cost/Time |
|
Washington/Idaho/ |
1:500,000 |
$87K |
|
Montana state maps |
(4 plates) |
(3 months) |
|
USGS Map I-667 |
1:24,000 |
$2K |
|
(Swales Mtn.) |
(1.5 quads) |
(3 months) |
|
USGS Map I-1028 |
1:62,500 |
$8K |
|
(Carlin-Pinon Range) |
(4 quads) |
(3 months) |
The U.S. Geological Survey (USGS), Office of Mineral Resources, Branch of Western Mineral Resources (WMR) has a requirement for digital geologic map data production services. The service needed at this time is to digitize state geologic maps and production of topologically structured ARC/INFO (TSAI) files. TSAI data files include all geologic information on a geologic map including faults and other structural-geologic information and lithologic information at a scale of 1:500,000. The purpose of these data files are to provide the digital data necessary to reproduce any or all of the information contained in the published geologic map using ARC/INFO version 6.0 or newer software.
If any of the criteria or formats defined in this statement of work significantly impact the cost, the Contractor can propose a proven, most cost effective alternative that meets the Government's purpose.
The contractor shall deliver TSAI data to USGS in accordance with the specifications described here. Completed work includes the digitization of all geologic information on the geologic map and the production of the TSAI data files meeting ARC/INFO data export file specification (version 6.0) or newer) and the USGS specifications detailed in Attachment B (Data structure for digital geologic maps).
The project addressed by this contract requires the production of TSAI data representing contacts, faults, fold axis, formation names, and other geologic information found of the specified state geologic map and defined in the legend of that map. All digitized data are to be complete, appropriately attributed, and topologically structured to allow for duplication of the published map using ARC/INFO software (version 6.0 or newer) or to allow for creation of a new map using any combination or selection of features and attribues.
3.1 Two (2) stable-base copies of the geologic map. The cleanest material available will be used; however in some case extraneous non-geologic information may be included on this material.
3.2 One published colored copy of the geologic map.
3.3 Shipment of GFM-Commercial shipment of the GFM by the government and the Contractor shall be by registered mail, return receipt requested. This requirement may be waived in the event other methods of shipment are more advantageous to the Government, e.g.,messenger, air freight, etc. If other than registered mail is used, a receipt shall be furnished by the Contractor to the Contracting Officer with a copy to the Contracting Officer's Representative (COR).
4.1 Topologically Structured ARC/INFO (TSAI) Data
4.1.1 The Contractor shall produce two TSAI data files in ARC/INFO export format (version 6.0 or newer) for the supplied map. The first TSAI data product will be the lithologic polygons (a polygon coverage). The second TSAI data product will be the structural geologic information (an arc coverage). TSAI data produced must meet the format specifications detailed in Attachment B.
4.1.1.1 The polygon and arc coverage will have some duplicate arcs because many of the faults will also be boundaries of lithologic polygons. The Contractor should make every effort to make these duplicate arcs identical in both TSAI data files.
4.1.2 The Contractor shall record the TSAI files representing the geologic map on computer compatible one-half inch, 9-track magnetic tape at 6400 BPI or some other alternate format, such as Internet ftp, as agreed with the COB at time of delivery. A tape should have a label indicating the map name, the Contractor's name, and the name of the data files.
4.2 Verification Plots--A minimum of two plots are required. These plots will contain the polygon and arc coverages. If the contractor is not able to plot the map, the USGS may, at their discretion, produce the plots.
4.2.1 Line verification--One plot on stable-base material at the scale of the GFM published map shall be delivered for each TSAI geologic map. The purpose of this plot is to verify the positional accuracy and attributes of all lines. Each plot shall be provided as a positive image on clear or translucent media (film or frosted mylar) 0.004" or thicker. The elements which shall be shown on the plots and symbology to used are indicated below.
4.2.1.1 The selection of line weights and other symbols should be similar to those on the GFM. The numbers given below are only listed as approximate sizes.
4.2.1.2 Nodes, points where 3 or more arcs intersect, might be plotted using a circle with a line weight of 0.005" and diameter of 0.080". The circle shall be centered over the recorded coordinates of the node. For pseudo nodes, points where 2 arcs join, and for hanging nodes, end points of an arc which does not join another arc, symbols might be diamonds and squares respectively.
4.2.1.3 All lines should be plotted with a distinctive line weight similar to those on the GFM. For example, all geologic contact and fold axis might be plotted with a line weight of 0.005". All faults might be plotted with a line weight of 0.010".
4.2.1.4 All dashed and dotted lines should be reproduced similar to those displayed on the published map.
4.2.1.5 All thrust faults and other decorated lines should be plotted with decorations similar to the published geologic map. These decorations must be on the same side as shown on the published map. Colored lines could also be used to help differentiate line types. See Attachment B for more information of decorated lines.
4.2.1.6 Plotting material shall measure an appropriate size to get the proof print on the minimal number of pages. In the case that the map will not plot on one page, one smaller scale plot should be provided to verify the registration across plotting page boundaries.
4.2.1.7 Tick marks measuring 0.1 in length and positioned and labeled with latitude and longitude on the latitude-longitude points shown on the GFM published geologic map shall appear on all plots with a distinctive fine line weight.
4.2.1.8 The following information shall be printed in the margin of all plots:
4.2.1.8.1 Plot generation date, plot scale, source-data map name, map authors, map scale, and map publication date (e.g. Geologic Map of Nevada, Stewart and Carlson, 1977)
4.2.1.8.2 Contractor name, name of the Contractors' contract, address, and phone number.
4.2.2 Polygon verification plot--one full color plot at the scale of the published map shall be delivered. The purpose of this plot is to verify the attributes of all polygons. Each plot shall be provided as a positive image on paper base or other appropriate media for good color display. The elements which shall be shown on the plots and the symbology to be used is indicated below.
4.2.2.1 All lines as defined above in section 4.3.1.
4.2.2.2 Because of the wide variety of hardware, there are many options how this might be colored. The purpose of the coloring is to provide a product with colors similar to the published map to facilitate verification of the assigned polygon (formation) attributes. Because these maps often combine colors and patterns the Contractor should select a display method that will make comparisons between the published map and the verification plot as easy and rapid as possible.
4.2.2.2.1 The coloring scheme should allow for easy identification of the attributes of small polygons. Solid colors are generally best for this objective.
4.2.2.2.2 The coloring scheme should be similar to the scheme used on the GFM published geologic map, but does not need to duplicate those colors. The objective is that similar colors will aid verification.
4.2.2.3 A colored legend should accompany this colored map which defines the relationship between colors and symbols on the map and the attributes of the lines and polygons.
4.2.3 Although the line weights specified may not be achievable, given the variety of plotting equipment and plotting media available, they should be as close to the original specifications as possible and must be completely legible and be precise enough to permit effective evaluation of the completeness and positional accuracy of the data produced.
4.3 Intermediate products--Other products, such as raster scanned images, that are made in the course of obtaining the TSAI data file could be of value to the Government. Such products would be considered in evaluation the Contractor.
4.4 Status Reports--Two (2) copies of a monthly status report shall be delivered to the COR by the tenth (l0th) calendar day after the end of each month, beginning with the month following the delivery of the GFM to the Contractor. The content of the report is specified in Paragraph 6.9. A status report is not necessary if the Deliverable Products can be completed in 40 days or less.
4.5 Final Report--Four (4) copies of a final report shall be delivered to the COR at the completion of the project. The content of the report is specified in Paragraph 6.10.
The following standards shall be met by the Contractor to ensure the quality and accuracy of the digital cartographic data provided to the Government.
5.1 The government intends to use these TSAI with ARC/INFO software (version 5.0.1 or newer). Knowledge of the full details of the formats necessary so the TSAI data can be imported and directly used with the ARC/INFO software with the ARC/INFO import procedure are the responsibility of the Contractor. Information regarding the ARC/INFO software may be obtained from: Environmental Systems Research Institute, Inc., 380 New York Street, Redlands, California.
5.2 Category-defined features that appear on the state geologic map of the government furnished materials shall be digitized and assigned attribute codes. Ninety-eight percent (98%) of the coded elements will be as shown on the GFM published geologic map. All formats in attribute tables will be in accordance with the standards contained in Attachment B. When proper attribute codes cannot be determined using Attachment B, the Contractor shall notify the COR for resolution. Resolution of these problems will often require the Contractor to involve a geologist experienced with state geologic maps and access to people with the necessary information to correctly tag the attribute.
5.3 The positional accuracy of ninety percent (90%) of all nodes shall be inside the true position of the node defined by the intersecting lines on the GFM scale-stable source. The positional accuracy of ninety percent (90%) of all vertices shall be inside the line as found on the GFM scale-stable source. The remaining ten percent (10%) of all TSAI elements shall be within 0.010" in any direction from the true (correct) position shown on the GFM scale-stable source.
5.4 Linear features shall be digitized with a point density sufficient to preserve the graphic quality of the feature as represented on the GFM. Thus, angularity of lines that is not visible on the GFM scale-stable source should not be visible on the digitized product when plotted at the same scale as the GFM scale-stable source
6.1 The Contractor shall perform the following tasks to produce the required deliverable products detailed in section 4.0. The TSAI data produced shall comply with the ARC/INFO export format (version 5.0.1 or newer) and the content and quality standards stated in Section 5.0 and Attachment B.
6.2 The Contractor shall furnish all personnel, labor, facilities, material, and any other items, except as otherwise provided as GFM, required to produce the necessary TSAI files required as deliverable items.
6.3 The Contractor will require the services of a geologist experienced in the use of geologic maps in order to properly attribute all of the elements shown upon the map. The Contractor shall document that such an experienced person is available to assist in solving questions about attributing.
6.3.1 The COR will provide consultation with the Contractor's geologist at least by telephone to help resolve attributing problems.
6.4 Task A--Preparation
Due to the wide variety of computer equipment used by private industry to perform work of the type required, and the varied production techniques used to optimize the operation of these systems, all preparation of digitizing media is the responsibility of the Contractor. The Government will not prepare or furnish any materials other than those identified as GFM.
6.5 Task B--Data Collecting and Attributing
The Contractor shall digitize and attribute all features defined in the legend of the published GFM and any Contractor materials derived from GFM as a result of Task A.
6.6 Task C--Editing
The Contractor shall edit the data collected in Task B as necessary to correct all attributing errors and element misalignments, to delete duplication and extraneous information, to add missing data, and to provide topological structure necessary to digitally reproduce the GFM published geologic map.
6.7 Task D--Processing
The Contractor shall perform all data processing required using the data produced through Task C to generate the TSAI data files in the ARC/INFO export format (version 5.0.1 or newer), and with the content and quality standards detailed in Attachment B and Attachment A, section 5.
6.8 Task E--Verification
For each TSAI data produced, the Contractor shall generate the verification plots detailed in Section 4.0. The Contractor shall inspect each TSAI data file produced under this contract to ensure full compliance with the standards detailed in Section 5.0 and Attachments B prior to delivery to the Government.
6.9 Task F--Status Reports
The Contractor shall prepare monthly status reports outlining significant work accomplished during the reporting month, including a percent-of completion summary for the TSAI geologic map. The report shall also discuss problems encountered during the reporting month, corrective action taken, and impact, if any, on delivery schedules.
6.10 Task G--Final Report
The Contractor shall prepare a final report detailing the equipment used and the procedures and processes followed in the generation of the TSAI data specified in this contract. The report shall include, but not be limited to, a description of the resources required (personnel and equipment hours) for the completion of Tasks A-E. Developmental problems associated with computer hardware and software shall be addressed. All deviations from the formats outlined in these specifications as allowed by these specifications shall be clearly reported.
6.10.1 The Contractor shall assess the potential for improvement of the TSAI production process and recommend changes to Government specifications that would improve the efficiency of the digital cartographic data production.
6.10.2 Summary of specialized comments in the Final Report as referenced in other parts of these specification.
6.10.2.1 New words added to the word list of attributes.
6.10.2.2 Changes in attribute tables lengths.
6.10.2.3 Convention for digitizing decorated lines.
6.10.2.4 Map projection used and all associated parameters.
Prior to acceptance by the Government, all products will be validated using one or more of the following types of inspection to determine the level of quality for each TSAI characteristics prior to acceptance. Failure of the delivered TSAI data file to pass all test and acceptance procedures described will result in a rejection of the entire product and the procedures detailed in Section 8.0 will apply.
7.1 Inspection Procedures for TSAI Characteristics The inspection procedures for the following TSAI characteristics will be performed by the Government for the verification of the TSAI data. In addition to the verification plots supplied by the Contractor, the Government will generate selected paper and scale-stable film plots from each delivered TSAI data file. ARC/INFO software (version 5.0.-1) will be used as part of the validation process. Inspections are intended to ensure compliance with stated standards for the following: 1) file format, 2) content completeness, 3) positional accuracy, 4) attribution accuracy and 5) topological fidelity. Specified objectives are indicated below:
7.1.1 Format--The ARC/INFO taperead and import commands will be used to import the data. Errors contained in the data that prevent the proper loading of the file into the ARC/INFO environment will cause the TSAI to be rejected.
7.1.2 Topology--Topology relationships contained in delivered TSAI data will be tested for logical consistency using ARC/INFO routines. Checks will be made for intersections such as extensions of lines through nodes, lines crossing other lines except nodes, and lines crossing themselves. Polygon (area) adjacency will be checked to ensure that area left and are right definitions of lines are consistent. Topological violations will cause the TSAI to be rejected.
7.1.3 Feature Content--Feature content will be performed by comparing both Contractor and Government generated verification plots against scale-stable and published GFM. All geologic map specified features appearing on the color proof must be represented on the plots. Extraneous, duplicate, or missing data will cause the TSAI to be rejected.
7.1.4 Positional Accuracy--A visual comparison will be made between Contractor supplied stable-base line-verification plot and GFM stable-base materials. A software comparison will be made between Government digitized test nodes and arcs and Contractor digitized features. Errors in position which exceed the accuracy standards detailed in Section 5.0 will cause the TSAI to be rejected.
7.1.5 Attributing--The attributing of elements contained in delivered TSAI data will be checked for conformance to specifications detailed in Attachment B. ARC/INFO software will be used to check the encoded data against a table of valid attribute codes to ensure that each code or combination of codes is valid for the category and element type. Further verification of the encoded data will be made by manual correlation of file listings, verification plots, and the color composites produced by the Government from GFM. Errors in attributing which exceed the standards in Section 5.0 will cause the TSAI to be rejected.
7.1.6 Corrections--The Government may choose to make minor edits, such as deleting extraneous and duplicate data, adding small amounts of missing data, or making minor positional corrections. This provision does not require the Government to make such correction, nor does it relieve the Contractor of responsibility for meeting all specifications of this contract. Edits may be made at the Government discretion when the number of elements to be edited does not exceed five percent (5%) of the total number of lines and nodes contained in the delivered file.
7.2 Acceptance Procedure
Products passing the inspections and test detailed in Section 7.0 will be accepted by the Government. The Contractor will be notified of acceptance, in writing, within thirty (30) calendar days from receipt by the COR of the deliverables.
Upon receipt of any deliverable product by the COR, the following procedures will apply:
8.1 The Contractor will be notified in writing that the deliverable was rejected and the cause for rejection.
8.2 Written notice will be forwarded to the Contractor within thirty (30) calendar days from receipt of the deliverable. All Contract supplied materials will be returned to the Contractor with the rejection notice.
8.3 The Contractor agrees to correct and ship at no additional cost to the Government, the rejected deliverable within twenty (20) calendar days from the receipt of the rejection notice. Corrected deliverables must meet stated TSAI standards.
8.4 New verification plots shall be produced upon completion of all corrections to rejected deliverables.
8.5 The corrected deliverables and new verification plots shall be delivered to the Government for testing as described in Section 7.0
The terminology used here is that of ARC/INFO (version 6)
1.1 Add to the polygon attribute table (PAT) as the last item, formation. The field length is 10, field width is 11, and the field type is character.
1.2 The information in this item will be formation symbol as shown on the GFM published map by a symbol or color. All of these names must appear in the legend associated with GFM published map. The symbol convention should reproduce the symbols as used on the map, e.g. Tv for Tertiary volcanics.
1.2.1 Certain characters used on the map will not have standard keyboard characters; so the following conventions should be used for these special symbols.
1.2.1.1 OL - Oligocene, EP - Paleocene, PL - Pliocene, CZ - Cenozoic, MZ - Mesozoic, PZ - Paleozoic, K - Cretaceous, TR - Triassic, PN - Pennsylvanian, PM -Carboniferous or Pennsylvanian-Mississippian, C - Cambrian, PC - Precambrian.
1.2.1.2 All superscripts or subscripts should be typed as normal characters, i.e. no superscripts or subscripts can be used. These should be lower case letters. The conventions used here should be noted in the final report.
1.2.1.3 Where the allowed work list does not include the appropriate word the Contractor should make an appropriate selection and document this in the final report on the project. If there seems to be confusion resulting from the selection of words, the selection should be discussed with the COB.
2.1 Add to the arc attribute table (AAT) as the last four items, [type, modifier, accuracy, and name].
2.1.1 Field lengths can be increased if required and this change should be documented in the final report.
2.2 The item ltype is for the type of line. The item length is 30, the item width is 31, and the item type is character.
2.2.1 ltype can have the following values: contact, fault, fold, other.
2.3 The item modifier denotes the type of contact, fault, fold or other. The item length is 20, the item width is 21 and the item type is character.
2.3.1 The following words can be used with faults: normal, thrust, reverse, strike-slip, strike dextral, strike-sinistral, none.
2.3.2 The following words can be used with folds: anticline, syncline, overturned anticline.
2.3.3 The following words can be used with other: map boundary, water boundary, or glacier boundary.
2.4 The item accuracy is a modifier denoting the positional accuracy on the location of the geologic feature. This does not refer to any aspect of the digitizing accuracy. This is normally shown on the map by the type of line, such as solid, dashed, or dotted lines. The item length is 15, the item width is 16, and the item type is character.
2.4.1 The following words can be used: certain, approx. located, inferred, inferred ?, concealed, concealed ?, gradational.
2.4.1.1 The query (?) after the word denotes that the line had ? along the line.
2.4.1.2 Solid lines are normally certain. Dashed lines are generally approximately located. Dotted lines are generally concealed. However this should be verified with the explanation that accompanies the GFM published map.
2.5 The item name is used only for those faults or folds that have identified names shown on the map. This item should include both upper and lower case characters as in normal writing with proper names.
2.5.1 The field length is 20, the field width is 21, and the field type is character.
2.6 Where the allowed word list does not include the appropriate word, the Contractor should make an appropriate selection and document this in the final report on the project. Additions to the allowed word list must be documented in the final report. If there seems to be confusion resulting from the selection of words, the selection should be discussed with the COR.
2.7 Decorated lines, that is those lines with some sort of symbol on one side of the line such as thrust faults, require that the lines be digitized in a fixed direction relative to the decorations so the decoration will plot on the side shown on the GFM published map. The convention to use is that these lines will be digitized in the direction that puts the decoration on the right side, e.g. if the decoration is on the east side of the line, then digitize from south to north.
2.7.1 The important thing is that all decorated lines are digitized in a standardized manner relative to the side the decoration is drawn. The convention used should be documented in the final report.
3.1 All coordinates of the TSAI data set will be x-y digitizer coordinates.