Arkosic sandstone

Let us now imagine a process of hydrothermal alteration of arkose sandstones composed of Mg-chlorite, K-feldspar, K-mica, and quartz. Because precipitating Si02 during alteration is amorphous, we will assume the presence of amorphous silica instead of quartz, and we will consider MgO as the generic oxide / and K2O as the generic oxide j. 

Uranium mineralization in the Windsor area is a typical sandstone roll-front type. The Green Street occurrence that is the focus of this study occurs in thick arkosic sandstones, siltstones, and pebbly conglomerates of the Cheverie Formation (Fig. 2). The occurrence is a remnant tail of a uranium roll front that has subsequently migrated down dip from the outcropping (Ryan O Beirne-Ryan 2007). 

Trenches excavated across the veins are typically flooded by surface water however, three partially flooded trenches have exposed bedrock. From small (< 5m ) outcrops exposed in three of the trenches, it is apparent that the average grain size of the clastic sedimentary rocks and the abundance of coarse-grained detritus, increases from NE to SW away from the buried Caradocian shale, with arkosic sandstone most abundant in the SW near the Christopher vein. An extensive array of 98 drill holes provides excellent downhole, 3-D control on our understanding of the geology. 

A Stratified Drift-Arkosic Sandstone Lithology The Bedrock Aquifer of New England... 

Walker T. R. (1984) Diagenetic albitization of potassium feldspar in arkosic sandstones. J. Sediment. Petrol. 54,3-16. 

DurroN, S.P. Land, L.S. (1985) Meteoric burial diagenesis of Pennsylvanian arkosic sandstones, southwestern Anadarko Basin, Texas. Bull. Am.. 455. petrol. Geol., 69, 22-38. 

Dutton Flanders examined the diagenesis and reservoir quality of the East Ford Field, Texas, which is undergoing a carbon dioxide flood. The compartmentalization of the arkosic sandstone reservoir is chiefly controlled by authi-genic calcite layers associated with the tops and bottoms of turbidite sandstone units. Gases produced from zones below low permeability calcite cemented sandstone intervals in new infill wells have high carbon dioxide contents. These, together with geophysical log interpretations, indicate that the calcite-cemented zones are laterally continuous and act as vertical barriers in the reservoir. 

Late Permian Mt. Glossopteris 700 Arkose, sandstone shale, coal, Glossopteris leaves, Dadoxylon,... 

To determine the detail geologic properties of studied quarry, samples were taken from different points in the quarry. As a result of microscopic analysis performed on these samples, studied quarry included five main rock types. These rocks were massive limestone (Kl), crystallize limestone (K2), arkosic sandstone (K3), quartz sandstone (K4) and intrusive diabase (K5). To observe the distribution of these rocks in the quarry, firstly, 1/3000 scales of engineering geology map were prepared. Afterwards, cross sections were made according to this map to display the relation of different rock types (Fig. 2). 

K3 Northern part Compose of quartz, feldispar, very few muscovite and seriate, the grain size is fine and well sorted, the grains are cemented by carbonates. Arkosic sandstone... 

To date, only a small number of deposits are known in Europe in Triassic sandstones the only notable prospect is located at Mazarate in the Guadalajara Province of Spain. Mineralization occurs in Lower Triassic red arkosic sandstones rich in volcanic debris and organic matter. Uranium appears as pitchblende and sooty pitchblende in reduced facies. 

Vandergrift GF, Winans RE, Scott RG, Horwitz EP (1980) Quantitative study of the carboxylic acids in Green River oil shale bitumen. Fuel 59 627-633 Walker TR (1984) Diagenetic albitization of potassium feldspar in arkosic sandstones. J Sediment Petrol 54 3-16... 

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