Blott, S.J. and Pye, K. (2001) GRADISTAT: a grain size distribution and statistics package for the analysis of unconsolidated sediments. Earth Surface Processes and Landforms 26, 1237‑1248. DOI: 10.1002/esp.261
Why is this software used so widely? It has applications in:
: Statistics are calculated in metric units (arithmetically and geometrically) and logarithmic phi units. Key Features Versatile Input
GRADISTAT processes your distribution curves using two fundamentally different mathematical principles. Reviewing both ensures your data interpretation is sound. Statistical Metric Method of Moments Folk & Ward Graphical Geological Meaning Uses the entire distribution curve Evaluates selected percentages ( Overall average energy of the depositional environment. Sorting Mathematical standard deviation Interpolated graphic standard deviation Indication of sediment transport consistency or duration. Skewness Measures total curve asymmetry Focuses on tails of the distribution Highlights presence of excess fine or coarse material. 🗺️ Visualizing Sediment Distribution
: Meant to define the uniformity of the sample population. gradistat v 91 hot
If you are a student struggling with your thesis data, or a consultant without a budget for fancy software, join the hunt for . Just remember to thank Simon Blott and Kenneth Pye when you cite their work—and always, always scan your .xla file for viruses.
Version 9.1 is one of the most widely cited releases of GRADISTAT. Many research papers explicitly state:
The legitimate and most secure way to obtain the updated GRADISTAT software is through the original creators, Kenneth Pye Associates Ltd.
Whether Gradistat v.91 Hot was a genuine advance, a happy accident, or a shared hallucination matters little. It represents a brief moment in science when one person’s hacked spreadsheet macro felt like magic — fast, dangerous, and just unstable enough to make every result feel earned. Blott, S
The term "hot" in this context has a double meaning, which is crucial for any user to understand.
The results can be used for further analysis, such as constructing ternary plots, differentiating between environments, or reconstructing paleo-depositional conditions.
is a widely used software package designed for the rapid calculation of grain size statistics, specifically tailored for researchers in geomorphology and sedimentology. It operates as an integrated program within Microsoft Excel, making it highly accessible for analyzing unconsolidated sediments. Core Functionality
A simple literature search reveals that GRADISTAT v9.1 continues to be cited in papers published well into the 2020s, from studies of reef islands in Indonesia to analyses of beach sediments in Sri Lanka. Earth Surface Processes and Landforms 26, 1237‑1248
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The software produces diverse graphical outputs, such as , cumulative plots , and ternary diagrams (e.g., sand-silt-clay classification). Applications in Research
is a highly popular, specialized software package built for Microsoft Excel to calculate grain size statistics and distributions for unconsolidated sediments. Originally developed by Simon Blott and Kenneth Pye in 2001, this tool has become a foundational asset for geologists, environmental scientists, and civil engineers worldwide. The rollout of version 9.1 represents a massive upgrade, bringing optimized VBA macros, smoother integration with modern versions of Excel, and enhanced graphical rendering engine capabilities.