CHAPTER 13: Unsafe Ground—Landslides and Other Mass MovementsMASS WASTING- GRAVITY transports larger quantities of Earth material down slopeFACTORS That Influence MASS WASTING- Earth Materialo SOLID ROCK Deformation (faults/folds) Mechanical/Chemical Weathering Foliated Metamorphic Rockso UNCONSOLIDATED MATERIAL Angle of Repose- max angle at which a slope of loose material will lie without cascading down Vegetation- plants add support against erosion- Water Content o Water fills pore spaces between sediments, add weight, and depending on the amount may reduce internal resistance. DRY PARTICLES—bound by SIZE AND FRICTION UNSATURATED—bound by SURFACE TENSION OF WATER SATURATED—particles act as LUBRICANT- Slopeo Process that can create steeper slopes FAULTING, FOLDING, TILTING QUARRYING, GROUND CUTSTYPES OF MASS WASTING- FALLo Solid rocks FALL RAPIDLY from STEEP or VERTICAL SLOPEo TALUS- rocky accumulation at foot of steep cliff- ROCK AVALANCHEo Flows by entraining AIR as its moves down SLOPE- SLIDEo Single mass of rock is RELEASED and MOVES RAPIDLY along a PLANE OF WEAKNESS- CREEPo Downhill movt. of soil or other depositso SLOWEST MASS WASTING PROCESS—mm/yr- SLUMPo RAPID SLIDE of soil or rock along a curved surfaceo “STAIRSTEPS”- FLOWSo HIGH WATER CONTENTo EARTHFLOW- SOILS (RELATIVELY SLOW)o DEBRIS FLOW- more COARSE then SAND, can carry huge BOULDERS and moves RAPIDLYo DEBRIS AVALANCE- mountainous areas, moves RAPIDLYo Mudflows/LaharsREMOVAL OF VEGETATION (DEFORESTATION) INCREASES MASS WASTING B/C OF LESS VEGETATION or STABILITYTRIGGERS OF MASS WASTING HEAVY RAINFALL EARTHQUAKES VOLCANOES HUMAN ACTIVITYo Added mass of buildings on slopeso Removal of VEGETATIONo Increased angles of slopeso Addition of waterCHAPTER 14: Running WaterInitial Runoff- “SHEET FLOW”—thin sheets of water depends on: intensity/duration of rainfall, soil texture, moisture, hill slope, vegetation small channel develops which feed streamsSTREAM TRANSPORTATION (in solution, in suspension, bed load—bottom) DISSOLVED LOAD- CHEMICALS DISSOLVED IN THE WATER SUSPENDED LOAD- FINER PARTICLES THAT ARE SUSPENDED IN THE WATER COLUMN—CLEAR TO MUDDY BED LOAD- MATERIAL IN THE STREAM CARRIES ALONG THE BED BY SLIDING, ROLLING and SALTATIONo Low velocities form rippleso High velocities form dunesSTREAM CHANNEL TYPES STRAIGHTo SINGLE channelso Forms on steep to low slopes BRAIDEDo MULTIPLE channelso Channels split apart & rejoino HIGH VOLUMES OF SEDIMENT MEANDERING o ONE MAIN channel that WINDS BACK & FORTHo Forms on LOW SLOPESo CUT BANK strongest currents on outside of curves, erosion occurso POINT BAR- velocity slowest on inside of curves, deposition occursDRAINAGE PATTERNS DENDRITICo FLAT LYING layers (similar rock type)—“tree” TRELLISo FOLDED rock layers RECTANGULARo Rock units cut by joints or faults—90 degree bends RADIALo HIGH MOUNTAIN PEAKS (volcanoes)FACTORS THAT INFLUENCE STREAM FLOW Velocityo Faster towards the center of streamo Distance water travels divided by time (ft/s or m/s) Gradiento Change in elevation divided by distance (rise/run)o Ft/mi—slope Dischargeo Volume of water that passes a certain point adjacent to a banko Area of stream x stream velocityo Feet Squared/second or Meter Squared/secondOTHER FEATURES OF STREAMS TERRACESo Marks previous levels of floodplains, formed by renewed down cutting to lower base level ALLUVIAL FANSo FAN SHAPED ACCUMULATIONS OF SEDIMENT.o Form where streams adjust velocity when leaving a narrow valleyfor a broad relatively flat area DELTASo Triangular shaped deposits of sediment deposited as streams enter ocean (velocity slows) NATURAL LEVEEo Ridges of coarse material built up during periods of flooding that act to confine the stream within its bankCHAPTER 16: Hidden Reserve—GROUNDWATERGROUNDWATER RECHARGE ( INFILTRATION )Depends on: CONDITION/TYPE OF SURFACE MATERIALS VEGETATION TOPOGRAPHY PRECIPITATIONUNCONSOLIDATED ROCK AS PARTICLE SIZE DECREASES, POROSITY INCREASES AND PERMEABILITY DECREASESCONSOLIDATED ROCK LOW POROSITY/PERMEABILITYCOARSE GRAIN=HIGHER PERMEABILITYFINE GRAIN=HIGHER POROSITYSORTING LESS POROSITY/PERMEABILITYCEMENTATION DECREASES POROSITY/PERMEABILITYGROUNDWATER STORAGEAQUIFER- sediment or rock that store and transmit groundwater in sufficient quantities (HIGH POROSITY/PERMEABILITY) UNCONSOLIDATED-mudstone/clay CONSOLIDATED-sandstone/conglomerateAQUITARD- sediment or rock through which water cannot move (POROSITY VARIES/LOW PERMEABILITY)- UNCONSOLIDATED-mudstone/clay- CONSOLIDATED-shale/slateUNCONSOLIDATED= open to surface (unsaturated/saturated zone)CONSOLIDATED= sandwiched between aquitards, not open to surfaceHOT SPRINGS vs. GEYSERSHot Springs- spring with water 6-9 degrees C, warmer than mean annual air temperatureGeysers- intermittent hot water fountains caused by boiling at depthEx. Yellowstone (HOT SPOT)GROUNDWATER WITHDRAW > GROUNDWATER RECHARGECONE OF DEPRESSION- EXCESSIVE PUMPING DRAWS DOWN THE WATER TABLE into a cone-shaped depression around a pumping well.SALTWATER INTRUSION- FRESH WATER IS LESS DENSE THAN SEA WATER and OVER PUMPING DRAWS SALT WATER INTO WELL NEAR OCEANSUBSIDENC- WEIGHT OF OVERLYING MATERIALS CAUSES COMPACTION AND SINKINGOF LAND SURFACE when WATER IS REMOVED FROM PORE SPACE/CRACKS IN SEDIMENT/ROCKS.EROSION BY GROUNDWATERDISSOLUTION- CHEMICAL WEATHERING process by which SLIGHTLY ACIDIC WATER DISSOLVES ROCK- LIMESTONE- KARST TOPOGRAPHY- name given to HILLY TERRAIN characterized by PRESENCE OF SINKHOLES, CAVERNS AND LACK OF SURFACE STREAMSo Spelothems- when minerals precipitateo Stalagmite=bottom up….stalactite=top to bottomGROUNDWATER POLLUTION- Gas Stations- Old Landfills/dumps- Evaporation ponds—industries- Chemical Spills- Sewage, feed lots- Radioactive waste- Pesticides, herbicides, fertilizerGROUNDWATER FLOW DIRECTION CAN CHANGE DUE TO HEAVING PUMPING OF A WELL.CHAPTER 15: OCEAN AND COASTSLANDSCAPES BENEATH THE SEACONTINENTAL MARGIN- CONTINENTAL SHELFo Broad, flat platform EXTENDING FROM SHORELINE to the beginning of the continental slope- CONTINENTAL SLOPEo A steeper, typically mud-draped slope MARKING EDGE OF CONTINENTAL SLOPEo Dissected by submarine canyons and modified turbidity currents- CONTINENTAL RISEo Gently sloping apron of sediment formed by DEPOSITION of sands and muds at base of continental slope- ABYSSAL PLAINo Extends beyond continental rise,