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  1. Title: Map of a portion of British Columbia showing the coalfields of Comox, Nanaimo & Cowitchin on Vancouver and adjacent islands and the distribution of the cretaceous coal bearing rocks also the tertiary rocks of Sooke & Burrard Inlet, to illustrate the report of Mr. James Richardson; compiled & drawn by R. Barlow, Ch. Draftsn., Geo. Sur.

    Contributors:

    Summary: Greenwich prime meridian. Relief shown by hachures and spot heights. Includes 3 profiles. 1 map: col.; 77 x 88 cm

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  2. Title: Geologic map of Minnesota, New Ulm sheet, bedrock geology

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    Summary: Map showing interpretations of bedrock geology (distribution of rock at the land surface and beneath surface sediments) of the New Ulm quadrangle, scale 1:250,000.

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  3. Title: Bathymetric Digital Elevation Model (200 meters): California Coast, 2002

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    Summary: This raster dataset is a mosaic resampled to 200 meter horizontal resolution for areas of sparse data occurrence. Vertical units are fathoms (integer). The tiled 25 meter base DEMs are intermediate products used to generate the 25-200 meter zonal DEMs. These 25, 50, 100 and 200 meter "zones" were defined by plotting the source data on paper, visually identifying and hand drafting zone boundaries based on data density, then capturing the boundaries in digital format. The tiled 5-200 meter zonal DEMs are simply the coast-wide zonal DEMs (or individual 5 meter zonal DEMs) clipped to a 7500 meter buffered tile extent and stored in the tile directory. This makes it easy to find DEMs of all available resolutions for a single tile. Tile directories store only those resolutions that cover the tile. A single coast-wide Digital Elevation Model (DEM) was envisioned as the product of the California Department of Fish and Game bathymetry development project, but it quickly became evident that the source data necessitated multiple datasets, including: 1) Coast-wide 25, 50, 100 and 200 meter zonal DEMs; 2) 5 meter zonal DEMs for localities supported by high-density source data; 3) Tiled 5, 25, 50, 100 and 200 meter zonal DEMs; and 4) Tiled 25 meter base DEMs. The grid is a resampled compilation of these datasets (available upon request). The bathymetry development project covered most of the 200 nautical mile Exclusive Economic Zone (EEZ) off the coast of California. The actual extent of data is slightly beyond this zone in some areas to account for the 100 km. tiles used to process source data (some tiles extend beyond the EEZ boundary by as much as almost a tile width, or less than 100 km.). To the east, the coverage includes many major inlets along the coast. The tiles also extend north and south of California by less than one tile height. These data are not suitable for navigation purposes. California Department of Fish and Wildlife, 2003. Bathymetric Digital Elevation Model (200 meters): California Coast, 2002. Marine Region GIS Lab. Available at: http://purl.stanford.edu/ns150wp8904. --BEGIN ORIGINAL METADATA - THIS INFORMATION MAY NOT BE CURRENT-- California Department of Fish and Game BATHYMETRY PROJECT Second Edition This document provides an overall description of the California Department of Fish and Game (DFG) bathymetry development project, including source datasets, processes used, and resulting products. The bathymetry data are not suitable for navigation. DFG makes no warranty as to the suitability of the bathymetry data, and any project-related datasets, for any purpose. In addition to this readme file, other documentation files (text, XML, etc.) may accompany datasets related to this project. ACKNOWLEDGEMENTS The bathymetry processing methods and documentation were originally developed by the State of California Stephen P. Teale Data Center, GIS Solutions Group (Teale) under DFG direction. Key Teale staff involved in the project included Andy Richardson and Virginia Wong-Coppin. REVISIONS A second edition of the bathymetry data was completed by DFG in August 2002. The second edition data were processed using ARC/INFO GIS software in a Windows 2000 operating system environment and included the following enhancements: - Correction or exclusion of over 1700 miscoded and suspicious Hydrographic Surveys used in the bathymetry development process. - Replacement of older U.S. Geological Survey 7.5-minute terrestrial elevation data with the newer/higher-quality National Elevation Dataset (NED) for use in nearshore bathymetry interpolation. - Minor adjustments to some of the ARC/INFO software ARC Macro Language (AML) scripts and resolution zone boundaries used to process the bathymetry data. GEOGRAPHIC AREA Bathymetry was developed to cover most of the 200 nautical mile Exclusive Economic Zone (EEZ) off the coast of California. The actual extent of data is slightly beyond this zone in some areas to account for the 100 kilometer tiles used to process source data (some tiles extend beyond the EEZ boundary by as much as almost a tile width, or less than 100 KM). To the east, the coverage includes many major inlets along the coast. The tiles also extend north and south of California by less than 1 tile height. VITAL STATISTICS Data Format: ESRI grid (DEMs) Horizontal Datum: NAD27 (spheroid: Clarke 1866) Projection: Albers conic equal area Units: Meters Z-Units (depth values): Decimeters (land coded as zero) 1st Std. Parallel: 34 00 00 (34.0 degrees N) 2nd Std. Parallel: 40 30 00 (40.5 degrees N) Longitude of Origin: -120 00 00 (120.0 degrees W) Latitude of Origin: 00 00 00 (0.0 degrees) False Easting: 0 False Northing: -4000000 RESULTING PRODUCTS Initially a single coastwide Digital Elevation Model (DEM) was evisioned to be the product resulting from this project. Upon commencing the project it became evident that due to the nature of the source data multiple datasets were appropriate. These include: 1. Coastwide 25, 50, 100, and 200 meter zonal DEMs 2. 5 meter zonal DEMs for localities supported by high-density source data 3. Tiled 5, 25, 50, 100, and 200 meter zonal DEMs 4. Tiled 25 meter base DEMs The coastwide 25-200 meter zonal DEMs are based on the fact that there is a wide variation in the density of the source data. Where data were dense, a 25 meter zonal DEM was generated. Where data were sparse, a 200 meter zonal DEM was generated. The 50 and 100 meter zonal DEMs represent intermediate densities. Though "coastwide", data in these DEMs do not overlap, however together they cover the entire study area. These 25, 50, 100, and 200 meter "zones" were defined by plotting the source data on paper, visually identifying and hand drafting zone boundaries based on data density, then capturing the boundaries in digital format. The 5 meter zonal DEMs correspond to areas where source data are particularly dense. These areas were identified by visually scanning the source data on-screen, and "heads up" digitizing the boundaries. These DEMs differ from the 25-200 meter zonal DEMs in that they were processed using different tolerances and that they were not merged into a single coastwide zonal DEM (due to resolution / storage constraints). These DEMs are available named by geographic localities or as tiled data. The tiled 5-200 meter zonal DEMs are simply the coastwide zonal DEMs (or individual 5 meter zonal DEMs) clipped to a 7500 meter buffered tile extent and stored in the tile directory. This makes it easy for a user to find DEMs of all available resolutions for a single tile. Tile directories store only those resolutions that cover the tile. The tiled 25 meter base DEMs are intermediate products used to generate the 25-200 meter zonal DEMs. These have proven useful as a source for generating contours and depth range polygons. They are also useful for visualizing and analyzing small geographic areas, though the user must understand that the source data do not necessarily support 25 meter resolution. These DEMs are tile-wide in extent, and are available clipped to the tile boundary (dembase) and buffered 7500 meters beyond the tile (dembaseb). An available georeferenced map image (bathy_map.jpg with bathy_map.jgw world file) shows spatial distribution, tile numbers, and resolution zones of the DEM data. SOURCE DATA Four sources of depth/elevation data were used to create the bathymetric DEMs: 1. Hydrographic Survey Data version 4.0, National Ocean Service (NOS), National Oceanic and Atmospheric Administration, U.S. Department of Commerce. Dataset name = hydsura (ESRI coverage format). 2. U.S. Geological Survey bathymetric contours for the California EEZ - 100m contours from 200m to maximum depth. Dataset name = eezbata (ESRI coverage format). 3. 30 meter terrestrial DEM based on the National Elevation Dataset (NED), U.S. Geological Survey, U.S. Department of the Interior. Dataset name = dema (ESRI grid format). 4. 1:24,000-scale State of California Coastline, State Lands Commission, State of California. Dataset name = rawclipa (ESRI coverage format). The NOS Hydrographic Surveys were the primary nearshore depth data used to create the bathymetric DEMs. These data represent multiple historical ship transects and were imported to ARC/INFO as a set of over 6 million points. Sampling density is quite variable, as close as a few meters in inland bays and as far apart as hundreds or thousands of meters away from the coast. The Hydrographic Surveys were processed as-is and not filtered to model a particular range of dates. The U.S. Geological Survey bathymetric contours were provided by the U. S. Geological Survey Coastal and Marine Geology Team. The original dataset known as "eezbatcall" was reprojected by DFG to the California (Teale) Albers projection. The coverage provided contours from 200 meters to maximum depth for the California EEZ area. The contours were digitized from various small-scale (approximately 1:1,000,000) U.S. Geological Survey maps. The 30 meter terrestrial DEM was used to allow continuous gridding along the coast. Though there is no land area included in the resulting products, the bathymetry gridding process requires sampling data beyond the edge of the resulting grid to smoothly interpolate depth/elevation along the edge. The NED terrestrial DEM data were distributed by the U.S. Geological Survey then processed and re-distributed by Teale. The 1:24,000 coastline was used to define land and water areas and as source depth points of "0". This results in a well-defined coastline in the bathymetric DEMs. The original State Lands Commission coastline coverage was modified by Teale for project purposes. PROCESSING DATA In addition to the source depth/elevation data, a number of datasets were used to control processing. These include: 1. TILE100KM 2. RES_ZONES 3. RAWCLIPA 4. M5_ZONES TILE100KM is a set of 100 kilometer square (10,000 square kilometers) tiles used to split the entire EEZ into 75 managable processing areas. Many of the resulting datasets are also stored by these tiles. RES_ZONES are zones corresponding to the density of source data that were used to determine the resolution of the resulting zonal DEMs (5, 25, 50, 100, and 200 meters). RAWCLIPA contains a set of polygons that define which areas are water and which areas are land. This dataset serves two functions in the gridding process. Coastlines are extracted, converted to a set of points with a depth value of "0", merged with the Hydrographic Surveys, U.S. Geological Survey bathymetric contours, terrestrial DEMs, and gridded. When gridding is complete, land polygons are pulled from this dataset and used to blank out the resulting DEM. M5_ZONES are areas where the Hydrographic Surveys support 5 meter gridding. The final products include a single 5 meter zonal DEM for each polygon in this dataset. PROCESSING METHODOLOGY The primary engine behind the gridding process is the ARC/INFO TOPOGRID tool. TOPOGRID uses an iterative finite difference interpolation technique that is essentially a discretized thin plate spline technology. It is based upon the ANUDEM program developed my Michael Hutchinson. The online help for TOPOGRID contains the following references: Hutchinson, M.F. 1988. Calculation of hydrologically sound digital elevation models. Third International Symposium on Spatial Data Handling, Sydney. Columbus, Ohio: International Geographic Union. Hutchinson, M.F. 1989. A new procedure for gridding elevation and stream line data with automatic removal of spurious pits. Journal of Hydrology: 106, 211-232. Hutchinson, M.F. and Dowling, T.I. 1991. A continental hydrological assessment of a new grid-based digital elevation model of Australia. Hydrological Processes 5: 45-58. Hutchinson, M.F. 1993. Development of a continent-wide DEM with applications to terrain and climate analysis. In: M.F. Goodchild et al (eds), Environmental Modeling with GIS. New York, Oxford University Press: 392-399. Wahba, G. 1990. Spline models for Observational data. CBMS-NSF Regional Conference Series in Applied Mathematics, Philadelphia: Soc. Ind. Appl. Maths. The following TOPOGRID parameters were used to create the 25-200 meter DEMs: DATATYPE SPOT ENFORCE OFF ITERATIONS 30 TOLERANCES 2.5 1.5 10 XYZLIMITS %LIMITS% (%LIMITS% = bounding box of buffered tile) The following TOPOGRID parameters were used to create the 5 meter DEMs: BOUNDARY XXZONE (XXZONE is the 5 meter zone polygon) DATATYPE SPOT ENFORCE OFF ITERATIONS 30 TOLERANCES 2.5 1.5 2.5 XYZLIMITS %LIMITS% (%LIMITS% is 50 meters beyond the 5 meter zone polygon bounding box) The processing logic applied to each of the 75 tiles to create the 25-200 meter DEMs was: - Receive the tile number to process - Create a results directory corresponding to the tile number - Extract the tile from TILE100KM - Buffer the tile 10 KM - Using the buffered tile, clip out: - RES_ZONES - RAWCLIPA (land water polygons) - Hydrographic Surveys - Coastlines (from RAWCLIPA) - Convert to points - Terrestrial DEM (if tile covers land area) - Convert to points - U. S. Geological Survey bathymetric contours (if tile covers 200 meter zone) - Merge all point coverages - Run TOPOGRID to create 25 meter DEM covering buffered tile area - Blank out land areas - Clip to 7500 meters beyond tile boundary; store in tile directory - Clip to tile boundary; store in tile directory - For each resolution zone covered by the tile: - Clip out area from buffered DEM - Resample to appropriate resolution for zone (using bilinear interpolation) - Blank out land areas - Store in tile directory The process used to create the 5 meter DEMs is: - For each polygon in M5_ZONES: - Create a coverage containing a single rectangle polygon 50 meters (10 5 meter cells) larger than the zone polygon - Using the rectangle, clip out: - RAWCLIPA (land water polygons) - Hydrographic Surveys - Coastlines (from RAWCLIPA) - Convert to points - Terrestrial DEM (if tile covers land area) - Convert to points - Merge the resulting point coverages - Run TOPOGRID to create 5 meter DEM covering the rectangle - Blank out land areas - Clip to extent of the zone polygon After the original tiled 25 meter base DEMs were created by Teale, shaded reliefs were generated and visually inspected. Miscoded points that resulted in spurious pits or spikes were identified and coded as such. After all errors were corrected for a tile, the DEMs for the tile were re-created and re-inspected. DIRECTORY STRUCTURE The following outline illustrates the directory structure used to process the bathymetry data. When fully populated, the TILEx directories are quite large (several gigabytes). - BATHYMETRY - AMLS (ARC/INFO AML data processing scripts) - DATA (source and processing data) - PROCESS (bathymetry processed here) - RESULTS (contains various results directories) - METER5 (5 meter zonal DEMs, named by localities) - OTHER (empty) - STATE (25, 50, 100, 200 meter coastwide zonal DEMs) - TILES (contains tile1-tile75 directories) - TILEx (contains tiled and base DEMs) - DEMBASE (25 meter base DEM clipped to tile) - DEMBASEB (25 meter base DEM buffered 7500 meters beyond tile) - DEM5 (5 meter zonal DEM buffered 7500 meters beyond tile) - DEM25 (25 meter zonal DEM buffered 7500 meters beyond tile) - DEM50 (50 meter zonal DEM buffered 7500 meters beyond tile) - DEM100 (100 meter zonal DEM buffered 7500 meters beyond tile) - DEM200 (200 meter zonal DEM buffered 7500 meters beyond tile) DATA QUALITY ASSESSMENT The following are subjective comments regarding the data. Because the bathymetry data were generated from a variety of sources at varying scales, overall accuracy is difficult to assess. The data have not been thoroughly reviewed. Depth values should be corroborated with other sources. Some "artifacts" are present in the data, and may be especially noticeable along resolution zone and tile boundaries where differing data sources may not have provided a smooth interpolation transition. Additional errors may be present. Source Hydrographic Survey data originated from many historical surveys and thus do not necessarily represent current hydrologic conditions. For accuracy assessments of Hydrographic Survey data, please reference the documentation for that product. DEM depth values are of particular questionable quality in the following areas. Other problem areas may exist. - Nearshore areas north of Mack Pt. (southern Oregon). Source terrestrial elevation data was missing for this area but depth values were still interpolated to the shoreline. - Nearshore, Gulf of the Farallones area, south of Stormy Stack and north of Muir Beach out to about -25 meters depth. Source depth data was missing for this area but depth values were still interpolated to the shoreline. - Nearshore areas south of the California border out to -200 meters depth. Source depth and terrestrial elevation data were missing for this area but depth values were still interpolated to the shoreline. - Any depth values outside of the gridding resolution zones. Cross-reference the "tile100km" and "res_zones" coverages used in data processing to determine areas within tiled DEMs that are outside the resolution zones. The georeferenced map image (bathy_map.jpg with bathy_map.jgw world file) can also be used for this purpose. - San Diego Bay. Source data were missing for portions of the bay but depth values were still interpolated. ACCESS LIMITATIONS None. Acknowledgement of the Bathymetry Project in products derived from the data is appreciated. DATA CONTACT Will Patterson California Department of Fish and Game Information Technology Branch GIS Service Center Sacramento, CA Voice: (916) 323-1484 Fax: (916) 323-1431 Email: wpatters@dfg.ca.gov Readme Version 2002.08.23 --END ORIGINAL METADATA-- This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

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  4. Title: Map illustrating the overland expedition from Port Denison to Cape York, (Australia) under the command of F & A. Jardin Esq. to accompany Mr. Richardson's paper

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    Summary: Relief shown by hachures and spot heights. Route of the party and their camps is marked in red. From: the Journal of the Royal Geographical Society of London. Vol. 36, (1866), pp. 19-51; held in Firestone Library. Call number: G7 .J687 vol.36 1866.

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  5. Title: Soil Expansive

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    Summary: Expansive Soils are defined as Maximum Measured Shrink-Swell Potential and were grouped by consultant Sean Wilson, geologist. Data originates from the NRCS Soils data known within the County of Marin GIS database as Soils. NRCS soils were downloaded from ftp://ftp.tfw.nrcs.usda.gov/pub/ssurgo/online98/data/ca041/ . This data set is a digital soil survey and generally is the most detailed level of soil geographic data developed by the National Cooperative Soil Survey. The information was prepared by digitizing maps, by compiling information onto a planimetric correct base and digitizing, or by revising digitized maps using remotely sensed and other information. This data set consists of georeferenced digital map data and computerized attribute data. The map data are in a soil survey area extent format and include a detailed, field verified inventory of soils and miscellaneous areas that normally occur in a repeatable pattern on the landscape and that can be cartographically shown at the scale mapped. A special soil features layer (point and line features) is optional. This layer displays the location of features too small to delineate at the mapping scale, but they are large enough and contrasting enough to significantly influence use and management. The soil map units are linked to attributes in the National Soil Information System relational database, which gives the proportionate extent of the component soils and their properties.

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  6. Title: Geologic atlas of Stearns County, Minnesota, C-10, Part B, Plate 10, Sensitivity of Ground-Water Systems to Pollution

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    Summary: Map showing the susceptibility of the ground water system (bedrock and unconsolidated sediments) to contamination, including the age of the water as determined from radioactive isotopes in the water, scale 1:100,000, Stearns County.

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  7. Title: Geologic atlas of Stearns County, Minnesota, C-10, Part B, Plate 9, Hydrogeology of the Quaternary Confined Aquifers and Bedrock Aquifers

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    Summary: Maps showing ground water resources and aquifer characteristics of confined Quaternary aquifers (aquifer surrounded by water impermeable material, usually clayey glacial till) and bedrock aquifers, scale 1:100,000, Stearns County.

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  8. Title: Geologic atlas of Stearns County, Minnesota, C-10, Part B, Plate 8, Hydrogeology of the Quaternary Water-Table System

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    Summary: Maps showing ground water resources and aquifer characteristics in the bedrock and unconsolidated sediments (glacial and stream sediments) overlying the bedrock and interactions between surface and bedrock aquifers, scale 1:100,000, Stearns County.

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  9. Title: Geologic atlas of Fillmore County, Minnesota, C-8, Part B, Plate 6, Bedrock Hydrogeology

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    Summary: Maps showing where and how much ground water may be present and aquifer characteristics of the bedrock geologic units, scale 1:100,000, Fillmore County.

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  10. Title: Geologic atlas of Fillmore County, Minnesota, C-8, Part B, Plate 7, Pollution Sensitivity

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    Summary: Map showing the susceptibility of the ground water system (bedrock and unconsolidated sediment aquifers) to contamination, scale 1:100,000, Fillmore County.

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  11. Title: Shorter contributions to the geology of the Sioux Quartzite (early Proterozoic), southwestern Minnesota, RI-32, Plate 1

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    Summary: Generalized interpretations of bedrock geology (distribution of rock at the land surface and beneath surface sediments) of the North Limb, Cottonwood County Basin, Jeffers-Comfrey area, Minnesota, scale 1:48,000.

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  12. Title: Shaded relief aeromagnetic anomaly map of northeastern and east-central Minnesota, M-53

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    Summary: Aeromagnetic anomaly map, (relative to the earth's magnetic field, interpretation of magnetic data collected from airborne surveys, the map colors indicate the distribution and concentration of magnetic minerals (primarily iron-bearing) within the upper crust of the earth, shaded-relief (psuedo 3d), northeastern and east-central Minnesota, scale 1:1,000,000.

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  13. Title: Geologic map of the Gunflint Lake quadrangle, Cook County, Minnesota, M-42

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    Summary: Interpretations of bedrock geology (distribution of rock at the land surface and beneath surface sediments) of the Gunflint Lake quadrangle, scale 1:24,000.

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  14. Title: Geologic map of the Hungry Jack Lake quadrangle, Cook County, Minnesota, M-39

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    Summary: Interpretations of bedrock geology (distribution of rock at the land surface and beneath surface sediments) of the Hungry Jack Lake quadrangle, scale 1:24,000.

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  15. Title: Geologic map of the South Lake quadrangle, Cook County, Minnesota, M-38

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    Summary: Interpretations of bedrock geology (distribution of rock at the land surface and beneath surface sediments) of the South Lake quadrangle, scale 1:24,000.

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  16. Title: General map of rainfall and temperature of Wisconsin, 1882

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    Summary: Relief shown with form lines. Includes cross-sections: On E.E. -- On C.D. -- On A.B. "Plate No. IIC." "The Milwaukee Litho. & Engr. Co." 68 x 58 centimeters Scale approximately 1:960,000 General Map Collection

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  17. Title: Plano de Yerba Buena, Alta California (Raster Image)

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    Summary: This layer is a georeferenced image of a site plan Plano de Yerba Buena, Alta California. For descr. see: Harlow, N. The Maps of San Francisco Bay ... 1850, no. 31.Pen-and-ink and watercolor on tracing paper.Oriented with north to right."No. 280, City of San Francisco, San Francisco, Exhibit no. 2 A.F., filed in office Aug. 20, 1853, Geo. Fisher." Shows drainage, settlements, etc. Relief shown pictorially. A scanned version of this map was georeferenced as part of the Imagined San Francisco project. This project traces the history of urban planning in San Francisco, placing special emphasis on unrealized schemes. Rather than using visual material simply to illustrate outcomes, Imagined San Francisco uses historical plans, maps, architectural renderings, and photographs to show what might have been. By enabling users to layer a series of urban plans, the project presents the city not only as a sequence of material changes, but also as a contingent process and a battleground for political power. Savvy institutional actors--like banks, developers, and many public officials--understood that in some cases to clearly articulate their interests would be to invite challenges. That means that textual sources like newspapers and municipal reports are limited in what they can tell researchers about the shape of political power. Urban plans, however, often speak volumes about interests and dynamics upon which textual sources remain silent. Mortgage lenders, for example, apparently thought it unwise to state that they wished to see a poor neighborhood cleared, to be replaced with a freeway onramp. Yet visual analysis of planning proposals makes that interest plain. So in the process of showing how the city might have looked, Imagined San Francisco also shows how political power actually was negotiated and exercised. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.

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  18. Title: Hydrogeology of the Paleozoic bedrock in southeastern Minnesota, RI-61, Plate 2

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    Summary: Cross section of Paleozoic bedrock from central Mower County east showing hydrostratigraphic (water bearing rock units) attributes and classification of aquifers and confining units (rock units that prevent water movement in the vertical direction), scale 1 inch = about 7 miles.

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  19. Title: Hydrogeology of the Paleozoic bedrock in southeastern Minnesota, RI-61, Plate 1

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    Summary: Cross section of Paleozoic bedrock from the northern part of the Twin Cities Metropolitan area south to central Mower County showing hydrostratigraphic (water bearing rock units) attributes and classification of aquifers and confining units (rock units that prevent water movement in the vertical direction), scale 1 inch = about 7 miles.

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  20. Title: Geologic atlas of Mower County, Minnesota, C-11, Part B, Plate 10, Karst Hydrogeomorphic Units

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    Summary: Maps showing distribution of karst (carbonate rock with caves, springs) units and features and karst hydrology in carbonate rocks susceptible to being dissolved by acidic ground water, scale 1:100000, Mower County.

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