Australian Soil Classification: Haplic, Petroferric, Brown CHROMOSOL (confidence level 1)
General Landscape Description: Low Hills / Rises
Site Description: Upper slope
Land Unit: Dundas Sedimentary
Geology: Tertiary marine sandstone
General Land Unit Description: This site is situated on low hills with a Tertiary capping. Due to restrictions of scale, this site is not mapped as the Dundas land unit. It has been used to illustrate the variability in the parent material in the dissected landforms in the north-west of the study area. The most distinguishing feature of this soil is a thin petroferric pan. The pan occurs at 60 cm, which is slightly deeper than is common. Underneath the pan there is a band of heavy clay that overlies Tertiary quartz river gravels, which have proven to be gold bearing. The river gravels are not necessarily common. The petroferric pan may be the result of a fluctuating watertable.
Soil Profile Morphology:
Surface Soil | |||
A11 | 0-15 cm | Reddish brown (10YR5/4); fine sandy loam, moderate medium to fine subangular blocky structure; weak consistence, dry; pH 5.1; gradual change to: | |
A12 | 15-30 cm | Yellowish red (5YR4/6); fine sandy loam; weak fine subangular blocky structure; weak consistence, dry; contains many medium subangular ferruginous nodules; pH 5.4; abrupt and wavy change to: | |
Subsoil | |||
B21 | 30-60 cm | Yellowish red (50YR4/6) with very few fine faint yellow mottles; medium clay; weak subangular blocky structure; firm consistence, dry; contains a few small subangular ferruginous nodules; pH 5.9; sharp and wavy change to: | |
Pan | 60-75 cm | Very strongly cemented continuous ferruginous pan; sharp and wavy change to: | |
B22 | 75-90 cm | Red (2.5YR4/6) , with many coarse prominent yellowish brown (10YR5/6) mottles; heavy clay, moderate polyhedral structure; strong consistence, dry; contains very few fine ferruginous nodules; pH 6.0; clear to gradual change to: | |
B23 | 90-130 cm | Quartz river gravels |
- | pH | Salinity | ||
Surface Soil (A11 horizon) | Strongly Acid | Very Low | Non-Sodic | None1 |
Subsoil (30-60 cm) | Moderately Acid | Very Low | Non-Sodic | None |
Deeper Subsoil (75 -90 cm) | Moderately Acid | Very Low | Non-Sodic | None |
Horizon | Horizon Depth (cm) | pH (water) | pH (CaCl2) | EC dS/m | Organic Carbon % | Total Nitrogen % | Exchangeable Aluminium ppm | Exchangeable Acididty meq/100g | Exchangeable Cations | Coarse Sand (0.2-2.0 mm) % | Fine Sand (0.02-0.2 mm) % | Silt (0.002-0.02 mm) % | Clay (<0.002 mm) % | Field Capacity % w/w | Wilting Point % w/w | |||
Ca | Mg | K | Na | |||||||||||||||
meq/100g | ||||||||||||||||||
A11 | 0-15 cm | 5.1 | 4.3 | <0.05 | 2.7 | 0.17 | 46 | 9.4 | 1.2 | 0.43 | 0.41 | 0.08 | 27 | 47 | 10 | 13 | 17.7 | 7.2 |
A12 | 15-30 cm | 5.4 | 4.7 | <0.05 | 12 | 6.3 | 1.8 | 0.71 | 0.2 | 0.07 | 26 | 45 | 11 | 20 | 17.7 | 7.8 | ||
B21 | 30-60 cm | 5.9 | 5.3 | <0.05 | <10 | 6.7 | 3.0 | 2.1 | 0.24 | 0.1 | 22 | 30 | 7 | 43 | 25.2 | 14.3 | ||
B22 | 75-90 cm | 6.0 | 5.8 | 0.05 | <10 | 6.1 | 2.9 | 4.2 | 0.15 | 0.15 | 7 | 27 | 9 | 59 | 35.4 | 21.3 |