1 Overnight temperatures are generally quite mild with an average low of 11.4 Â°C (52.5 Â°F). 2  The mean diurnal temperature variation/ range in July is 7.5 Â°C (13.5 Â°F).  The weather in July is slightly dry with rain periodically. Only 50mm (2in) of H2O is deposited across an average of 17 days.
Chemical sedimentary rock forms when mineral constituents in solution become supersaturated and inorganically precipitate. Common chemical sedimentary rocks include oolitic limestone and rocks composed of evaporite minerals such as halite (rock salt), sylvite, barite and gypsum.
The most common clastic sedimentary rocks are breccia and conglomerate (formed from gravel), sandstone (from sand), siltstone (from silt), and shale (from clay). B. CHEMICAL SEDIMENTARY ROCKS. Chemical sedimentary rocks are crystalline, that is made of crystals interlocked with each other.ediment is a general term that indicates loose grains (such as the sand at the beach) and chemical precipitates (such as crystals of salt). Sedimentary rocks can be subdivided in three categories: clastic, chemical, and biochemical sedimentary rocks.