8.1 The Basic Concepts of Groundwater 8.1.1 The Spaces and Moisture in Rocks (2)隔水层（不透水层）(aquiclude): 不能给出水的岩层，或给出微不足道水的 岩层，如粘土层 (3)半透水层：介于上两者之间
（2）隔水层（不透水层）（aquiclude）： 不能给出水的岩层，或给出微不足道水的 岩层，如粘土层。 （3）半透水层：介于上两者之间， 8. 1 The Basic Concepts of Groundwater 8.1.1 The Spaces and Moisture in Rocks
.several basic concepts: 1)Permeability(渗透性)：The ability of a material to allow fluids to pass through an interconnected network of pores is a characteristic known as permeability. A permeable material（透水物质)is one through which water flows easily,whereas an impermeable material is one through which water flows slowly or not at all. The permeability of a material depends on several factors:
•several basic concepts: (1)Permeability （ 渗透性 ） :The ability of a material to allow fluids to pass through an interconnected network of pores is a characteristic known as permeability. A permeable material （ 透 水 物 质 ） is one through which water flows easily,whereas an impermeable material is one through which water flows slowly or not at all. The permeability of a material depends on several factors:
8.1 The Basic Concepts of Groundwater 8.1.1 The Spaces and Moisture in Rocks Number of available conduits Size of the conduits Straightness of the conduits
Number of available conduits Size of the conduits Straightness of the conduits 8. 1 The Basic Concepts of Groundwater 8.1.1 The Spaces and Moisture in Rocks
8.1 The Basic Concepts of Groundwater 8.1.1 The Spaces and Moisture in Rocks (2)aquifers and aquitards Aquifers(含水层)：sediment or rocks that transmit water easily. Aquitards(弱透水层)：sediment or rocks that do not transmit water easily and therefore retard the motion of water
(2)aquifers and aquitards Aquifers （ 含水层 ） :sediment or rocks that transmit water easily. Aquitards（弱透水层）:sediment or rocks that do not transmit water easily and therefore retard the motion of water. 8. 1 The Basic Concepts of Groundwater 8.1.1 The Spaces and Moisture in Rocks
8.1 The Basic Concepts of Groundwater 8.1.1 The Spaces and Moisture in Rocks Aquicludes(隔水层)：sediment or rocks that do not transmit water at all. unconfined aquifers（无压含水层)：aquifers that intersect the surface of the Earth confined aquifers(承压含水层)：aquifers that are separated from the surface by an aquitard or aquiclude ,as the water they contain is isolated from the surface
Aquicludes（隔水层）:sediment or rocks that do not transmit water at all. unconfined aquifers （ 无 压 含 水 层 ） :aquifers that intersect the surface of the Earth . confined aquifers（承压含水层）:aquifers that are separated from the surface by an aquitard or aquiclude ,as the water they contain is isolated from the surface. 8. 1 The Basic Concepts of Groundwater 8.1.1 The Spaces and Moisture in Rocks