Heart Palpitation: 8 Reasons for Your Abnormal Heartbeat. Heart palpitations occur when the heart beat increasesâit may noting a flutter, skipped beat, or heart rate thatâs abnormally hard and fast in your chest, throat, or neck. Heart palpitations can be frightening if youâve never experienced them before.
a combining form meaning âwater,â used in the formation of compound words: aquiclude; aquiculture; aquifer. Also, aqua-. Origin of aqui-.
Typical aquifer cross-section. An aquifer is an underground layer of water-bearing permeable rock, rock fractures or unconsolidated materials (gravel, sand, or silt) from which groundwater can be extracted using a water well.n unconsolidated aquifers, groundwater is produced from pore spaces between particles of gravel, sand, and silt. If the aquifer is confined by low-permeability layers, the reduced water pressure in the sand and gravel causes slow drainage of water from the adjoining confining layers.