AGS Legend Codes - GEOL_LEG
The hatching pattern in the geology legend column of UK borehole logs is typically driven by the specification of a three-digit 'AGS Legend Code'. The field that relates to this value is GEOL_LEG, and is recorded in the GEOL data group for each stratum.
The table below lists some of the most commonly-used legend codes.
Table of AGS Legend Codes
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| Legend Code | Description |
| 101 | TOPSOIL |
| 102 | MADE GROUND |
| 103 | Bituminous Material |
| 104 | CONCRETE |
| 105 | Wood |
| 108 | Brickwork |
| 109 | MADE GROUND COHESIVE |
| 110 | MADE GROUND GRANULAR |
| 201 | CLAY |
| 202 | Silty CLAY |
| 203 | Sandy CLAY |
| 204 | Gravelly CLAY |
| 205 | Cobbly CLAY |
| 206 | Bouldery CLAY |
| 207 | Silty sandy CLAY |
| 208 | Silty gravelly CLAY |
| 209 | Silty cobbly CLAY |
| 210 | Silty bouldery CLAY |
| 211 | Silty sandy gravelly CLAY |
| 212 | Silty sandy cobbly CLAY |
| 213 | Silty sandy bouldery CLAY |
| 214 | Silty sandy gravelly cobbly CLAY |
| 215 | Silty sandy gravelly bouldery CLAY |
| 216 | Silty sandy gravelly cobbly bouldery CLAY |
| 217 | Silty sandy organic CLAY |
| 218 | Silty sandy gravelly organic CLAY |
| 219 | Silty organic CLAY |
| 220 | Sandy gravelly CLAY |
| 222 | Sandy cobbly CLAY |
| 223 | Sandy bouldery CLAY |
| 224 | Sandy gravelly cobbly CLAY |
| 225 | Sandy gravelly bouldery CLAY |
| 226 | Sandy gravelly cobbly bouldery CLAY |
| 227 | Sandy organic CLAY |
| 228 | Sandy gravelly organic CLAY |
| 229 | Organic CLAY |
| 230 | Gravelly cobbly CLAY |
| 231 | Silty gravelly cobbly CLAY |
| 301 | SILT |
| 302 | Clay/Silt |
| 303 | Sandy SILT |
| 304 | Gravelly SILT |
| 305 | Organic SILT |
| 309 | Clayey sandy SILT |
| 310 | Sandy gravelly SILT |
| 312 | Clayey sandy gravelly SILT |
| 314 | Clayey sandy gravelly organic cobbly SILT |
| 316 | Sandy cobbly SILT |
| 317 | Sandy bouldery SILT |
| 318 | Sandy organic SILT |
| 319 | Sandy gravelly organic SILT |
| 320 | Sandy gravelly cobbly SILT |
| 321 | Sandy gravelly organic cobbly SILT |
| 322 | Gravelly cobbly SILT |
| 323 | Gravelly bouldery SILT |
| 324 | Gravelly organic SILT |
| 325 | Gravelly organic cobbly SILT |
| 326 | Cobbly SILT |
| 327 | Cobbly bouldery SILT |
| 328 | Organic cobbly SILT |
| 331 | Bouldery SILT |
| 332 | Sandy gravelly clayey cobbly SILT |
| 401 | SAND |
| 402 | Clayey SAND |
| 403 | Silty SAND |
| 404 | Gravelly SAND |
| 405 | Cobbly SAND |
| 406 | Bouldery SAND |
| 407 | Clayey silty SAND |
| 408 | Clayey silty gravelly SAND |
| 409 | Clayey silty gravelly cobbly SAND |
| 410 | Clayey gravelly SAND |
| 411 | Clayey gravelly cobbly SAND |
| 412 | Silty gravelly SAND |
| 413 | Silty gravelly cobbly SAND |
| 414 | Silty gravelly cobbly bouldery SAND |
| 415 | Gravelly cobbly SAND |
| 416 | Gravelly cobbly bouldery SAND |
| 417 | Gravelly bouldery SAND |
| 418 | Cobbly bouldery SAND |
| 419 | Silty cobbly SAND |
| 430 | SAND and GRAVEL |
| 431 | Organic SAND |
| 433 | Silty organic SAND |
| 434 | Gravelly organic SAND |
| 435 | Cobbly organic SAND |
| 436 | Bouldery organic SAND |
| 501 | GRAVEL |
| 502 | Clayey GRAVEL |
| 503 | Silty GRAVEL |
| 504 | Sandy GRAVEL |
| 505 | Organic GRAVEL |
| 506 | Cobbly GRAVEL |
| 507 | Bouldery GRAVEL |
| 509 | Clayey sandy GRAVEL |
| 510 | Clayey cobbly GRAVEL |
| 511 | Clayey bouldery GRAVEL |
| 512 | Clayey organic GRAVEL |
| 513 | Clayey sandy cobbly GRAVEL |
| 517 | Clayey sandy organic GRAVEL |
| 520 | Silty sandy GRAVEL |
| 521 | Silty cobbly GRAVEL |
| 522 | Silty bouldery GRAVEL |
| 523 | Silty organic GRAVEL |
| 524 | Silty organic sandy GRAVEL |
| 525 | Sandy cobbly GRAVEL |
| 526 | Sandy bouldery GRAVEL |
| 527 | Sandy organic GRAVEL |
| 528 | Silty sandy cobbly GRAVEL |
| 601 | PEAT |
| 602 | Clayey PEAT |
| 603 | Silty PEAT |
| 604 | Sandy PEAT |
| 605 | Gravelly PEAT |
| 606 | Cobbly PEAT |
| 608 | Clayey sandy PEAT |
| 609 | Clayey gravelly PEAT |
| 612 | Silty sandy PEAT |
| 613 | Silty sandy gravelly PEAT |
| 614 | Sandy gravelly PEAT |
| 701 | COBBLES |
| 702 | Clayey COBBLES |
| 703 | Silty COBBLES |
| 704 | Sandy COBBLES |
| 705 | Gravelly COBBLES |
| 706 | Organic COBBLES |
| 708 | Clayey sandy COBBLES |
| 709 | Clayey gravelly COBBLES |
| 713 | Silty sandy COBBLES |
| 714 | Silty gravelly COBBLES |
| 715 | Silty organic COBBLES |
| 716 | Silty gravelly sandy COBBLES |
| 717 | Silty sandy organic COBBLES |
| 718 | Silty sandy gravelly organic COBBLES |
| 719 | Sandy gravelly COBBLES |
| 720 | Sandy organic COBBLES |
| 721 | Gravelly organic COBBLES |
| 725 | COBBLES and BOULDERS |
| 730 | BOULDERS |
| 731 | Gravelly cobbly BOULDERS |
| 801 | MUDSTONE |
| 802 | SILTSTONE |
| 803 | SANDSTONE |
| 804 | LIMESTONE |
| 805 | CHALK |
| 806 | COAL |
| 807 | BRECCIA |
| 808 | CONGLOMERATE |
| 809 | Fine grained IGNEOUS |
| 810 | Medium grained IGNEOUS |
| 811 | Coarse grained IGNEOUS |
| 812 | Fine grained METAMORPHIC |
| 813 | Medium grained METAMORPHIC |
| 814 | Coarse grained METAMORPHIC |
| 815 | Pyroclastic (volcanic ash) |
| 816 | Gypsum, Rocksalt |
| 817 | Shale |
| 818 | IRONSTONE |
| 819 | SLATE |
| 996 | Broken Ground |
| 997 | Undetermined |
| 998 | No Recovery |
| 999 | Void |