saprolite

They must be distinguished from less altered saprolite which has often a similar appearance and is also very widespread in tropical areas.

More intense weathering results in a continuous transition from saprolite to laterite.

Most of the gold was found in eroded rock (saprolite) and mixed in with quartz.

The texture, pH and mineral constituents of saprolite are inherited from its parent material.

Bedrock may also experience subsurface weathering at its upper boundary, forming saprolite.

Within the lower saprolite, violarite is transitional with unaltered pentlandite-pyrite-pyrrhotite ore.

Poorly weathered saprolite grit aquifers are capable of producing groundwater, often suitable for livestock.

They are leached from the upper horizons and reprecipitate with secondary iron-manganese oxides in the mid- to lower saprolite.

The saprolite is yellowish to reddish brown and strewn with garnet and ilmenite fragments and xenoliths.

It includes igneous, metamorphic, and sedimentary geology; the main types of rocks in the area are gneiss, slate and saprolite.

Among the controls on lavaka formation are the amount of seismic activity in the region, the topographic slopes, and hydraulic conductivity of materials in the saprolite.

Digenite occurs in the transitional zone of supergene oxidation of primary sulfide ore deposits, at the interface between the upper and lower saprolite ore zones.

Two types of nickel ore are of commercial importance, limonite (oxide) ore and saprolite (nickel silicate) ore.

The various forms of ironstone include siderite nodules; deeply weathered saprolite, i.e. (laterite); and ooidal ironstone .

The term saprolite is given to this type of regolith and it reflects the operation of isovolumetric weathering, that is, weathering accomplished without any change in volume.

A layer of saprolite (chemically weathered rock) separates the Bailey Rock Rhyolite formation from the overlying Caldera-Fill Sequence-era rocks.

In the Australian deposits, chrysoprase occurs as veins and nodules with brown goethite and other iron oxides in the magnesite-rich saprolite below an iron and silica cap.

Lavakas form where these hard laterites overlie thick (tens of metres) saprolite, on steep (35 to 55 degree) slopes, in areas that have a hot dry season and a warm wet season.

Nickel mineralisation in the regolith, in the upper saprolite typically exists as goethite, hematite, limonite and is often associated with polydymite and violarite, nickel sulfides which are of supergene association.

Where such soils are formed in conjunction with saprolite production, the biomantle is the bioturbated zone above the structured (unbioturbated) saprolite, with its base commonly defined by a stonelayer.

In most subtropical and tropical areas where deep and large volume bioturbators dwell, and in some midlatitudes like South Africa, such thick, two-layered biomantles (those with stonelayers) above structured saprolite are very common.

The DNi process has the major advantage of being able to treat both limonite and saprolite lateritic ores and is estimated to have less than half the capital and operating costs of HPAL or FerroNickel processes.

In lateritic regoliths - regoliths are the loose layer of rocks that rest on the bedrock - saprolite may be overlain by upper horizons of residual laterite; most of the original profile is preserved by residual soils or transported overburden.

These in turn are currently undergoing erosion by a combination of aeolian and fluvial processes, forming extensive sand dune systems, deep and prolonged development of laterite and saprolite profiles, and development of playa lakes, salt lakes and ephemeral drainage.

Often called "weathered granite", saprolite is the result of weathering processes that include: hydrolysis, chelation from organic compounds, hydration (the solution of minerals in water with resulting cation and anion pairs) and physical processes that include freezing and thawing.