Palsy means paralysis, but may also be used to describe uncontrolled muscle movement. Therefore, cerebral palsy encompasses any disorder of abnormal movement and paralysis caused by abnormal function of the cerebral cortex. In truth, however, CP does not include conditions due to progressive disease or degeneration of the brain.
Unlike weathering of granite or other hardrock, limestone weathering is often thought of as a purely chemical process in which groundwater or rain dissolve the rock, says Simon Emmanuel, a geologist at the Hebrew University of Jerusalem in Israel who led the new work, published in Geology.uilders and masons take note: When it comes to the durability of limestone, grain size matters. New research combining field and lab data shows that fine-grained limestone is more susceptible than its coarser-grained cousins to a one-two punch of chemical and mechanical weathering.
This process can be further subdivided into two categories: physical/mechanical weathering and chemical weathering. Chemical weathering refers to the processes by which rocks react with the atmosphere to form new substances. These reactions can alter a rock and transform the rock into sand, clays, and other minerals. CHEMICAL WEATHERING. Like mechanical weathering, there are several different types of chemical weathering. One type is oxidation, the reaction of oxygen with iron-bearing minerals in rock. In an oxidation reaction, the iron atom loses electrons and precipitates as another mineral.