What sort of sediment would felspathic sandstone mainly be comprised of?

Question

I've tried to google this and have got no where. Its for a quiz so any quick replies or ideas of where i may find the answers would be great!

Answer 1

Feldspathic sediments would be generated from the decomposition of granite, and therefore would contain feldspar, orthoclase, plagioclase, horneblende, quartz and mica.

Answer 2

The minerals "feldspar" & "quartz".

The more typical name for a feldspathic sandstone (i.e. one with a high feldspar content) is an arkose. Arkoses are predominantly composed predominantly of quartz (as per other types of sandstone) but are characterized by up to 25% feldspar. The feldspars are typically pinkish in colour (orthoclase) or whitish in colour (plagioclase), in contrast to the more glassy coloured quartz, and are therefore result in quite a distinctive looking rock.

Arkoses typically form as the weathering product of granite, and so other minerals found in granite alongside feldspar will also be found in arkoses, albeit in smaller quantities (mica, hornblende, rock fragments, etc.). Typically the feldspars themselves begin to weather and break down into clay minerals such as kaolinite, illite, etc.

Answer 3

Sandstone that contains feldspathic grains and is of granitic origin is called "arkose". It is basically just weathered granites and will contain the same mineralogy as the parent un-weathered material. This can include quartz, micas (muscovite, biotite ect.) and feldspars (as others have listed)

Answer 4

Sandstone, the sedimentary rock is composed of small grains that are cemented by siliceous, felspathic, or calcareous cementing material. The cementing material determines the durability of the sandstone. This coarse-grained sedimentary rock is formed by the consolidation and aggregation of sand and held together by a natural cement, such as silica. The sandstone comprises of :
Quartz grains
Feldspar grains
Rock fragment grains
It is the percentage composition of these components, that brings about variation in color and pattern of different types of sandstone
Sandstone Chemical Properties


The compositon of sandstone is quite similar to that of sand, that essentially consists of quartz. The natural cementing material which binds the sand together as rock is usually composed of silica, calcium carbonate, or iron oxide. The percentage constitution of each constituent varies between certain limit, which is as follows:

SiO2 ---------------------------------- 93-94%
Alumina(Al 2O 3) ------------------- 1.4 to 1.5%
Iron(Fe2 O3 ) ------------------------ 1.5%-1.6%
Lime(CaO) -------------------------- 0.8% to 0.9%
Soda(Na2 O) & Potash (Kro) -- 1.0% to 1.2%
Loss On Ignition(LOI) ----------- 1.0% to 1.2%
Magnesia(MgO) --------------------0.2 to 0.25%

Answer 5

Feldspar (hence feldspathic) like plagioclases and orthoclase.