Log Types

Both borehole views and cross section views display logs. Several different log types can be created in Strater. To create a log in either the borehole view or cross section view, click the Log | Create Log | [log type] command. Click on the screen where the log should be created. In the Open dialog, select the table to use or data file to import and click Open. The log is displayed with the default options.

 

Click the Example numbers for sample log illustrations:

 

Depth

Depth logs are used as a scale bar to display the depth or elevation of the data in the log or cross section pane. True vertical depth can be displayed on a depth log, if azimuth and inclination (or dip) are available for the wells. Examples:   1, 2

 

Line/Symbol

Line/symbol logs are used to display data as a symbols with connected lines. Line/symbol logs are useful for displaying assay values, geophysical parameters, moisture content, etc. Example 1

 

Crossplot

Crossplot logs are used to display intersections of two data curves on a graph. Crossplot logs can be used to characterize properties such as porosity, water saturation, or clay content by comparing where two logs intersect. Example 1

 

Zone Bar

Zone bar logs display data as filled blocks within intervals, and can show a wide variety of logging data. For instance, zone bars can represent sample intervals, alteration zones, contamination layers, etc. Examples:  I, 2

 

Bar

There are two types of bar logs: standard bars and polarity bars. Standard bar logs plot a bar from the data minimum value to the row's data value. Polarity bar logs plot data based upon zero so there are bars on both sides of zero if there is a mix of negative and positive data. Examples: 1, 2.

 

Percentage

Percentage logs are similar to bar logs. Percentage logs display the percentage of each alteration in a sample; the amounts of sand, clay, gravel, silt, etc. The percentage log uses data to create either a series of blocks (interval data) or polygons (depth data) that always add up to 100%. Examples:   1, 2, 3.

 

Tadpole

Tadpole logs are used to display dip and dip direction down the borehole. This gives an indication of strike and dip of bedding planes, fractures, or any other structure along the depth of the borehole. The symbols, colors, and labels can be altered to display the most useful information along the well. Example:1

 

Post

Post logs are used to display a symbol and text at the data position. The symbols can represent sample locations at depth or intervals, and in the case of monitoring wells, the depth to water, contamination, etc.

 

Classed Post

Classed post logs are similar to the post logs, except classed post logs use range schemes and numerical values to determine the symbol properties. Example: 1

 

Complex Text

Complex text logs show text in intervals. This type of complex text is generally used for rock descriptions, alteration descriptions, or any general descriptive text that represents interval data. Long text blocks are wrapped to fit within the log width. Separator styles can be used to separate text in long descriptions, and if adjacent sections contain the same text they can be combined into a single, larger section. Examples 1, 2

 

Graphic

Graphic logs allow you to specify image file names and show the images at specified intervals. This is useful in displaying photos of the core, rock type, alteration, etc. Example 1

 

Lithology

Lithology logs show the various stratigraphic layers in the borehole. The display can be as simple as a filled block from the top to bottom, or the display can be more elaborate and show weathering patterns and line types. Example:   1

 

Well Construction

Well construction logs replicate a well construction diagram for the log, and is generally used in the environmental industry. This log type shows items such as screen, packing material, end caps, and covers.

 

Registered and Unregistered Raster

An unregistered raster log is a scanned image of a paper or electric log without depth-registration information. It is easy to depth-register the unregistered raster log with Strater. Once the depth registration is complete the log can be used in cross sections and modified with the properties in the Property Manager. A registered raster log is a scanned image of a paper or electric log with a depth registration file. Registered raster logs can be used in cross sections and modified with the properties in the Property Manager.

 

Function

Function logs combine multiple existing log variables into a new log using mathematical formulas. The log variables being combined can contain different depth spacings and be from different tables. A new table is created from the output data of the input logs. Example: 1

 

See Also

Borehole View

Overlay Logs