Regional Groundwater Flow Flashcards
subsurface flow in a groundwater basin is considered to be _______ in nature
regional
groundwater recharge is about _____ times the lake’s catchment area
1.5x
movement of water is a ________ phenomenon
three-dimensional
what is the heterogeneity and anisotropy of the Philippine lithology?
heterogenous and anisotropic
the primary method through which water enters an aquifer
recharge
an area in which groundwater is discharged to the land surface
groundwater discharge zone
an area in which water enters an aquifer
groundwater recharge zone
recharge areas are usually located in _______ and with _______ water table
topographic high places ; deeper
discharge areas are usually located in __________ and with ________ water table
topographic low places ; shallow
manifestations of discharge areas
spring, seep, lake, or streams
manifestation of discharge in densely vegetated areas
wet soil
manifestation of discharge in arid areas
thicker vegetation cover or salt deposit
in the presence of fractures, recharge rate will _____
accelerate
water moves from the wetland into the groundwater
recharging wetland
water moves from groundwater into the wetland
discharging wetland
_______ can cause wetlands to shift back and forth from discharging to recharging
fluctuating water table
groundwater availability map of the Philippines was created in what year?
1977
a line in two-dimensional groundwater flow field such that the total hydraulic head is the same everywhere on the surface
equipotential line
t or f: equipotential line is 2D
true
t or f: in an equipotential line, hydraulic head is equal everywhere on the surface
T
represents the height of the water table or potentiometric surface of a confined aquifer, above a datum plane
equipotential lines
connects points or equal head
equipotential lines
idealized paths followed by particles of water as they move through the aquifer
flow lines
plays a role in the settlement pattern of many lands
spring
__________ and __________ are though to have therapeutic value
mineralized and thermal
mineralized and thermal springs are found along:
inactive volcanoes or surface with residual heat
springs can be _______ or _________
permanent or ephemeral
provide simple mechanism of springs
topographic low spots
forms when water table reaches the surface
depression spring
where do swamps naturally form?
in depression springs where water table is shallow and reaches the surface. over time, trees and shrubs begin to fill in the land.
these springs are formed when relatively permeable rocks overlie rocks of low permeability
contact spring
t or f: depression springs are only formed in unconfined aquifer
T
are formed when faulting causes groundwater under hydrostatic pressure (such as in confined aquifers) can move up along such faults
fault springs
are formed at topographic lows when water table reaches the surface due to topographic undulations
depression spring
are formed when large quantities of water move through the cavities, channels, conduits and other openings developed in limestones.
sinkhole springs
occur due to existence of jointed or permeable fracture zones in low permeability rocks
joint springs
are formed whene fractures intersect the land surface, movement of groundwater is mainly through fractures that may tap shallow as well as deep aquifers.
fracture spring
some of the largest spring are found on
limestone bedrocks
springs on limestone bedrocks can either be:
diffused flow in pores and fractures;
channelized flow in caverns
a river that runs wholly or partly beneath the ground surface
subterranean river
a ___________ has a channelized flow in caverns
subterranean spring
example of subterranean river in the Philippines
Puerto-Princesa Subterranean River
t or f: all surface water interact with groundwater
T
