20121009
000000
portsmouth_bedrock_data_points
vector digital data
Bedrock geology data points
Source of individual data points listed in the data_src field in associated attribute table.
PORTSMOUTH_DATA_POINTS contains bedrock geology point data for the quadrangle mapped at a scale of 1:24,000, from the Department of Conservation, Maine Geological Survey. Printed maps published by the Maine Geological Survey on USGS 7.5' quadrangle bases. Bedrock geology points delineated and digitized by the Maine Geological Survey from data compiled on USGS 7.5' quadrangle bases (Full description of each point type is contained in the associated attribute table).
Delineate bedrock characteristics. Bedrock maps indicate the distribution, lithology, age, and structural characteristics of bedrock units, and the stratigraphic, intrusive, and structural relationships among rock units. Symbols indicate locations of specific bedrock features such as the occurrence of natural outcrop exposures, occurrences of particular rock or mineral types, orientations of stratigraphic or structural features, and other features of interest noted in the field by the geologist. This information has a wide variety of uses by environmental or geotechnical consultants, hydrogeologists, mineral prospectors, rock and stone producers, soil scientists, ecologists, and geologists.
Irregular
-70.001084
-69.872632
44.250254
44.124798
Maine GIS Thesaurus-Theme
geology, bedrock
ISO Keyword Thesaurus
geoscientificInformation, imageryBaseMapsEarthCover
Maine GIS Thesaurus-Place
Maine, United States
GCMD Parameter Keyword
solid earth
ISO 19115 Topic Categories
geoscientificInformation
None
Users must assume responsibility in determining the usability of this data for their purposes. User must include full citation (author, pubdate, title, and source fields in associated attribute table) for the bedrock geology points when using the data in printed or digital form.
Maine Department of Conservation (MEDOC), Maine Geological Survey (MGS)
mailing
22 State House Station
Augusta
Maine
04333
USA
207-287-2801
mgs@maine.gov
Credit should be given to the data source and/or originator when data is transferred or printed. Source should be cited as: Maine Department of Conservation, Maine Geological Survey, 22 State House Station, Augusta, ME 04333-0022.
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 3; ESRI ArcGIS 10.0.3.3600
24000
hardcopy
USGS 1:24,000 7.5' quadrangles used as mapping base
Vector
Entity point
50
NAD 1983 UTM Zone 19N
0.9996
-69.0
0.0
500000.0
0.0
coordinate pair
0.000000002220024164500956
0.000000002220024164500956
Meter
D North American 1983
GRS 1980
6378137.0
298.257222101
portsmouth_bedrock_data_points
FID
Internal feature number.
ESRI
Sequential unique whole numbers that are automatically generated.
OBJECTID
Internal feature number.
ESRI
Sequential unique whole numbers that are automatically generated.
state_id
Unique state-wide point identification number for bedrock data location.
MGS
quadname
Name of 7.5-minute USGS quadrangle.
MGS
type_code
A 1-character or 2-character code that indicates what type of geologic feature is being reported in that row. This code is necessary for displaying symbols on the geologic map, each type of feature being represented by a particular symbol.
MGS
see definition in type_expl field in associated attribute table
MGS
type_expl
Explanation of type codes used in the quadrangle.
MGS
see associated attribute table
MGS
azimuth
Strike or Trend. If the Feature type code refers to a planar feature (such as bedding) or a linear feature (such as a fold axis), the orientation of that feature must be specified, using the two fields labeled azimuth and angle. The Strike or Trend is an azimuth in degrees, that must be a number between 0 and 360 (inclusive).
Strikes (of planar features) is reported according to the “right-hand-rule” convention, in which the strike is 90 degrees less than the dip direction. This means that strikes between 0 and 90 dip to the southeast; strikes between 90 and 180 dip to the southwest; strikes between 180 and 270 dip to the northwest; and strikes between 270 and 360 dip to the northeast. For horizontal planes, a default strike of zero is used (though technically the strike is undefined); for vertical planes, either end of the strike line may be used.
Trends (of linear features) are always reported in the down-plunge direction. For vertical lines (plunge = 90), a default trend of zero is used (though technically the trend is undefined); for horizontal lines, either end of the trend line may be used.
If the Strike or Trend is not known, a value of -1 (negative one) is used.
MGS
angle
Dip or Plunge. If the Feature type code refers to a planar feature (such as bedding) or a linear feature (such as a fold axis), the orientation of that feature is specified, using the two columns labeled azimuth and angle. The Dip or Plunge is an angle measured in degrees, that must be between 0 (horizontal) and 90 (vertical) (inclusive).
Dips (of planar features) and plunges (of linear features) are always measured downward from horizontal, in a vertical plane.
If the Dip or Plunge is not known, a value of -1 (negative one) is used.
modifier
The modifier is intended to distinguish between features that are basically all of the same type, but which differ by some secondary characteristic. For example, several localities in the quadrangle may have upright bedding, which would be assigned the same type code and have the same map symbol. But a modifier may be used in order to distinguish between sites with graded beds and sites with cross-beds, by assigning a modifier (such as “gr” for graded beds or “x” for cross-beds) that would be plotted next to the bedding symbol on the map.
MGS
see definition in mod_expl field in associated attribute table
MGS
mod_expl
Explanation of modifiers used in the quadrangle.
MGS
see associated attribute table
data_src
Formal citation of the data source. In most cases, the source of the data will be original field work by the geologist submitting the file.
Example 1: Henry N. Berry IV, Maine Geological Survey, 2007-2008, original data.
In some cases, however, data may have been compiled from existing sources such as published maps, unpublished thesis maps, well logs, etc. This is allowable as long as the data source is properly acknowledged.
Example 2: Arthur M. Hussey II, 1971, Geologic Map of the Portland Quadrangle, Maine. Maine Geological Survey map GM-1, 1:62,500.
Listing the source of data separately from the “person submitting this file”, allows someone to submit data collected by someone else, but the person submitting the file is responsible for any errors that may occur. Citing the original source allows questions to be investigated and errors to be corrected. Each data file must contain data from only one source. If data are being submitted from more than one source, they must be submitted in separate data files.
MGS
descriptio
submit_by
Name of the person who actually delivered the file to MGS. (This might not be the person who collected the data, or the person who created the file.) This is the one person responsible for the data file.
MGS
method
This field describes how the data were collected. If they are original data, then they were collected by field work. If they are pre-existing data, then they may have been transcribed from existing maps or copied from data tables or log sheets. This may be a lengthy comment, if it was a complex procedure.
Example 1: Field work.
Example 2: Data recovered by digitizing symbols from existing paper map.
Example 3: Data transcribed from Table 12, p. 134-138 of thesis.
MGS
submit_dat
Shape
Feature geometry.
ESRI
Coordinates defining the features.
Attribute table for bedrock geology feature arcs.
20121009
Maine Department of Conservation (MEDOC), Maine Geological Survey (MGS)
mailing
22 State House Station
Augusta
Maine
04333
USA
207-287-2801
mgs@maine.gov
FGDC Content Standard for Digital Geospatial Metadata
FGDC-STD-001-1998
local time
Users must assume responsibility in determining the usability of this data for their purposes. User must include full citation (author, pubdate, title, and source fields in associated attribute table) for the bedrock geology points when using the data in printed or digital form.