Soil developed on acid sulfate marine clay soil; dark brown (7.5YR 3/2, 3/, 3/4) to brown (10YR 4/3, 5/3); common jarosite (2.5Y 6/6, 6/8, 7/6, 7/8, 8/6, 8/8) mottles; clay; moderate, coarse subangular blocky to prismatic; sticky and plastic; shallow to acid sulfate layer pH < 3.5; poorly drained; occurs on flat terrain; cation exchange capacity 20-25 cmol(+) per kg soil ; low base saturation ; sulfuric diagnostic horizon.