b'Data trends Data trendson a quick visit to the GSSA. A simple sounding solution that shines with recursive beauty.Start with wide spaced gridding of real data and include the data values generated (pseudo data/points/stations) to create a smaller spaced grid.At its simplest (see Figure 1):1. Grid points x distance apart (black circles) with 1/4 spacing2. Observe three (pseudo) points generated between the original data points (the red and green circles)Tim Keeping3. Convert the grid into a data setAssociate Editor for geophysical data4. Delete the first and third pseudo data management and analysispoints (red circles)technical-standards@aseg.org.au 5. You now have a data set with half the original spacing (x/2)6. Set X = X/2 and repeat from step 1 until satisfied.Pseudo data, artefacts andAt step 5, you could replace the recursion - its all about the run up remaining middle pseudo data (green circle) with a nearby real data point. Grids accumulate artefacts with everyMore cells between data points smooths process as they migrate away from theirout differences and your algorithm original self. Merging grids inevitablyhas enough run up to fit this real data involves combining data sets withwithout (at least less) incongruity.different DC shifts, and false edge effects occur as surrounding cells ramp up orYou could recursively grid any image down in transition to a new local DC.down to as small a cell size as possible. Merging point data often imposes moreThe hard part is sorting your point data irregularity onto already irregular spacedinto your spacing groups. Spacings (x) data and the grid develops pimplesthat are multiples of two are easiest to where unlevelled points overlap. Variabledeal with, but dont let that stop you density gridding merges well but often,experimenting.if set to retain original data values, can produce a pimply visual experience.A description of this methods Some methods retain original valuesapplication to the 2016 South by stamping them onto a finished gridAustralian Gravity Grid can be found that, formed without using those explicithere: https://sarigbasis.pir.sa.gov.au/values, can impose incongruities. AWebtopEw/ws/samref/sarig1/image/beneficial idea casually came from theDDD/RB201700012.pdfalways humble Clive Foss, who was Figure 1.Points used and created by a gridding process. Original data (black circle) spaced distance X apart. Generated pseudo data (green and red circles) are created X/4 distance apart. Green circle indicates point value used in the next iteration of gridding points at X/2 distance apart. This may be a pseudo data value or substituted with a real value.DECEMBER 2020 PREVIEW 46'