Percentage data from devices such as the Beckman Coulter laser particle-size analyzer.
GRADISTAT V 9.1 is the latest iteration of the widely utilized particle size analysis software package, primarily designed for geomorphologists and sedimentologists. Initially developed by and Professor Kenneth Pye in 2001, this tool has become a standard in environmental research for analyzing unconsolidated sediments. Core Functionality
Assessing grain size in coastal zones to mitigate erosion and flood risks.
The software produces diverse graphical outputs, such as , cumulative plots , and ternary diagrams (e.g., sand-silt-clay classification). Applications in Research
Gradistat has evolved from its original 2001 release to Kenneth Pye Associates Ltd's later updates like , which was optimized for Excel 2007–2010. While a fully revised version known as GRADISTAT-PRO is under development, researchers continue to rely on the robust statistical frameworks provided by Version 9.1.
Gradistat V 9.1 calculates a comprehensive suite of grain size statistics using both and the Folk and Ward (1957) graphical methods . Statistical Parameter Methods Supported Average Size Arithmetic, Geometric (metric), Logarithmic (phi units) Sorting Standard Deviation (measures of uniformity) Skewness Measures of symmetry in distribution Kurtosis Peakness or flatness of the distribution curve Descriptive Terms
The software operates within as a macro-enabled workbook, allowing researchers to rapidly process large datasets—typically at a rate of approximately 50 samples per hour . It is compatible with data obtained from various measurement techniques, including: Manual Sieving: Weight retained on a series of sieves.
Researchers use Gradistat V 9.1 to characterize sedimentary environments and understand depositional energy dynamics. For instance:
Analyzing lake sediment cores to identify hydroclimatic shifts over tens of thousands of years.