All chalk and no greensand
This is the website I was talking about today when walking above Blewbury.
Wasn't that easy to navigate and find the map, but try this
Click anywhere and you get a description of the bedrock.
The green at Harwell (where it says A34)
UPPER GREENSAND FORMATION - CALCAREOUS SANDSTONE AND SILTSTONE
South of Blewbury, from where it says A417
Darker Green HOLYWELL NODULAR CHALK FORMATION - CHALK
Lighter Green ZIG ZAG CHALK FORMATION - CHALK
Yellowish WEST MELBURY MARLY CHALK FORMATION - CHALK
Pinkish WEST MELBURY MARLY CHALK FORMATION - CHALK (seems like the same to me)
Well done to spot the transition from Holywell to Zig Zag
Idioms like all chalk and no greensand come to mind.