is a widely used computer program designed for the rapid analysis of grain size statistics from unconsolidated sediments. Originally developed by Simon J. Blott and Kenneth Pye in 2001, it operates as a Microsoft Excel-based package
that simplifies complex calculations required to classify sedimentary environments. Michigan Technological University Core Functionality
The program calculates essential grain size parameters from data obtained via standard techniques like sieving or laser granulometry. Its primary outputs include: Michigan Technological University Mean Grain Size
: Represents the average size of sediment grains in a sample. Sorting (Standard Deviation)
: Indicates the uniformity of grain sizes, ranging from very well sorted to very poorly sorted.
: Measures the asymmetry of the grain size distribution curve (e.g., very positively skewed to very negatively skewed).
: Reflects the "peakedness" of the distribution, classified into categories like leptokurtic or platykurtic. Versions and Methods gradistat v 91 hot
While the original release was significant, researchers often use updated versions such as GRADISTAT v9.1 to handle modern data types like laser diffraction particle size distributions . The software computes statistics using multiple methods: Horizon IRD Arithmetic and Geometric : Calculated in metric units (microns). Logarithmic (Phi Units) : Uses the phi ( ) scale, a standard in sedimentology where Statistical Models : Implements both the Method of Moments Folk and Ward graphical methods Applications in Research
GRADISTAT is a standard tool in environmental and earth sciences for: Environmental Impact Analysis : Assessing sedimentation in dams and hydroelectric plants. Paleolimnology
: Interpreting past depositional energy and transport mechanisms in lake sediments. Soil Texture Classification
: Categorising samples according to international standards like the USDA soil texture classification mathematical formulas used in the Folk and Ward method or how to format your data for import into GRADISTAT?
GRADISTAT is a widely used Microsoft Excel-based software program designed for the rapid analysis of grain size statistics
in sedimentology. Developed by Simon Blott and Kenneth Pye, it streamlines the complex calculations required to classify unconsolidated sediments like sand, silt, and gravel. Kenneth Pye Associates Ltd 🛠️ Key Technical Features Rapid Processing : Capable of analyzing approximately 50 samples per hour. Statistical Methods : Calculations include Folk and Ward (1957) graphical measures and the Method of Moments Output Metrics is a widely used computer program designed for
: Provides results for mean, mode, sorting (standard deviation), skewness, and kurtosis. Multiple Scales : Computes data in both metric units (micrometers) and Versatile Inputs
: Accepts data from various standard measuring techniques, including dry/wet sieving and laser granulometry. Michigan Technological University 📊 Graphical Outputs
The program is highly valued for its ability to transform raw data into visual research tools: Frequency Plots : Displays the distribution of grain sizes within a sample. Cumulative Distribution Curves
: Shows the total percentage of material coarser or finer than a specific size. Ternary Diagrams : Generates triangular diagrams
(e.g., Folk or Shepard triangles) to show relative proportions of gravel, sand, and mud. 💻 Version History & Compatibility Release Date Compatibility Details Early 2000s The original published version for Excel 97/2000. Updated for use with Excel 2007 through 2010. v9.1 / PRO In Development
Modern updates aimed at improving functionality and compatibility with newer Excel versions. 🔍 How to Use GRADISTAT GRADISTAT v 4.0 Methodology and Models Step-by-Step: Running the Hot Version
I notice you're asking about "Gradistat v 9.1" (I assume "v 91 hot" refers to version 9.1, possibly a typo or shorthand). GradiStat is a granulometry (grain size analysis) program, commonly used for sedimentology and geomorphology.
Below is a proper report structure assuming you have run a grain-size analysis using Gradistat v9.1 and need to present the results professionally. I'll include sections, key outputs from Gradistat, and interpretation guidance.
Once you have secured gradistat v 91 hot, here is how to deploy it:
.xla (Excel Add-in), you must enable all macros in Excel (Developer tab -> Macro Security -> Enable all macros). Note: Restore this setting after use for security.Tools -> Add-ins (Excel 2003/2007) or File -> Options -> Add-ins (2010+). Browse to your gradistat_v91_hot.xla file.Before diving into the specifics of version 9.1, we must understand the problem it solved. Traditional sedimentology relies on the analysis of particle size distribution (PSD). Calculating statistical parameters—such as mean grain size, sorting (standard deviation), skewness, and kurtosis—used to be a manual, error-prone nightmare.
Enter Gradistat. Developed by Simon J. Blott and Kenneth Pye of the University of London, Gradistat was originally a Microsoft Excel add-in. It automated the complex logarithmic calculations required by the Folk and Ward (1957) graphical method and the moment method.
Instead of plotting cumulative curves by hand, a geologist could paste their sieve data or laser diffraction results into a spreadsheet, press a button, and receive a full suite of statistical outputs within seconds.
Modern sedimentary statistics programs are powerful, but they require specific dependencies (Java, .NET 6.0, or specific Python environments). In remote field stations or on ruggedized laptops running Windows 7 or 10 LTSC, bloatware fails. Gradistat v 91 hot is lightweight (usually less than 2 MB). It runs instantly.