MARINE GEOLOGY & GEOGRAPHY
Bathymetry BATHYMETRY
BATHYMETRY THE UNDERWATER EQUIVALENT TO TOPOGRAPHY THE STUDY OF WATER DEPTH A BATHYMETRIC MAP SHOWS FLOOR RELIEF OR TERRAIN AS CONTOUR LINES Bathymetry
INFORMATION COMES FROM: ECHOSOUNDERS (SONAR) BOUNCE SOUND WAVES OFF OF OCEAN FLOOR MAP THE DISTANCE FROM SEA LEVEL TO FLOOR CURRENT SONAR READS WIDE BANDS SIMULTANEOUSLY (MULTIBEAM)) BATHYMETRY Bathymetry
BATHYMETRY INFORMATION COMES FROM: SATELLITES MEASURE SLIGHT VARIATIONS IN SEA LEVEL SEA LEVEL IS HIGHER ABOVE MOUNTAINS AND RIDGES THAN ABYSSAL PLAINS Bathymetry
BATHYMETRY WHO COLLECTS THE DATA? ARMY CORPS OF ENGINEERS INLAND WATERWAYS, RIVERS, LAKES NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION (NOAA) OCEANS, SEAS, GULFS Bathymetry
OCEAN FLOOR FEATURES TWO MAIN DIVISIONS: CONTINENTAL MARGIN CONTINENTAL SHELF CONTINENTAL SLOPE CONTINENTAL RISE OCEAN BASIN PLAINS TRENCHES RIDGES & RISES SEA MOUNTS & GUYOUTS CORAL REEFS & ATOLLS Ocean Floor Features
CONTINENTAL MARGIN CONTINENTAL SHELF SUBMERGED PART OF CONTINENT GENTLE SLOPE TO OCEAN BASIN Ocean Floor Features
CONTINENTAL SLOPE EXTENDS FROM SHELF BREAK TO RISE BOUNDARY BETWEEN CONTINENTAL AND OCEANIC CRUST STEEP SLOPE CONTAINS SUBMARINE CANYONS CONTINENTAL MARGIN Ocean Floor Features
CONTINENTAL SLOPE SUBMARINE CANYONS FORM FROM RIVER EROSION TURBIDITY CURRENTS CONTINENTAL MARGIN Ocean Floor Features
CONTINENTAL MARGIN CONTINENTAL RISE FOUND AT BASE OF SLOPE FORMED FROM SEDIMENT DEPOSITION GENTLE SLOPE FROM SEA FLOOR TO SLOPE Ocean Floor Features
CONTINENTAL MARGIN ACTIVE: CONVERGENT PLATE BOUNDARIES TRENCHES NARROW MARGIN/ SHELF TECTONICALLY ACTIVE PASSIVE: NO PLATE BOUNDARY WIDE MARGIN/ SHELF THICK SEDIMENT LITTLE TECTONIC ACTIVITY Ocean Floor Features
OCEAN BASIN OCEAN BASIN FLOOR: ABOUT 30% EARTH S SURFACE BEGINS AT THE CONTINENTAL RISE MOSTLY ABYSSAL PLAINS WITH OTHER FEATURES Ocean Floor Features
OCEAN BASIN ABYSSAL PLAIN FLAT DEEP OCEAN FLOOR MAY BE MORE THAN 2 MILES DEEP THICK SEDIMENT ACCUMULATION Ocean Floor Features
OCEAN BASIN TRENCHES OCCUR AT SUBDUCTION ZONES OCEANIC CRUST IS FORCED INTO MANTLE ASSOCIATED WITH EARTHQUAKES DEEPEST= MARIANA S TRENCH 11000+ M LONGEST= PERU-CHILE TRENCH 5900+ KM Ocean Floor Features
OCEAN BASIN RIDGES & RISES UNDERWATER MOUNTAIN RANGES FORMED BY SEA-FLOOR SPREADING CONTAIN CENTRAL RIFT VALLEY RIDGES RISES STEEP SLOPE (SLOW MOVING PLATES) GENTLE SLOPE (FAST MOVING PLATES) Ocean Floor Features
SEAMOUNTS & GUYOUTS UNDERWATER VOLCANOES NEAR RIDGES AND OVER HOT SPOTS MAY EMERGE AS ISLANDS SEAMOUNTS- STEEP SLOPE JUTTING UP FROM SEA FLOOR GUYOUTS- FLAT TOP DUE TO EROSION OCEAN BASIN Ocean Floor Features
CORAL REEFS & ATOLLS OCEAN BASIN FORM AROUND VOLCANIC ISLANDS AND SEAMOUNTS ONLY FORM IN SHALLOW WATERS DORMANT VOLCANOES/ SEAMOUNTS ERODE AWAY AND BECOME A BARRIER REEF AND EVENTUALLY AN ATOLL BARRIER REEF- ACTIVELY GROWING CORAL REEF SURROUNDING A RECEEDING ISLAND ATOLL- SHALLOW LAGOON SURROUNDED BY MATURE CORAL REEF Ocean Floor Features
Ocean Floor Features
OCEANS OF THE WORLD REVIEW AVERAGE DEPTH 2.3 MILES SALINITY= 35 PPT (3.5% SALT) MAJORITY IS <39 F (4 C) MAJORITY IS DARK CONTAINS >97% OF THE EARTH S WATER Oceans of the World
OCEANS OF THE WORLD PACIFIC LARGEST AVG. DEPTH 14,500 FT BASIN COVERS 33% OF THE EARTHS SURFACE HOLDS 52% OF THE EARTH S WATER RING OF FIRE HIGHLY TECTONICALLY ACTIVE REGION 90% OF WORLD S EARTHQUAKES MARIANA TRENCH Oceans of the World
Oceans of the World
OCEANS OF THE WORLD ATLANTIC 2 ND LARGEST AVG DEPTH 12,500 FT MANY SHALLOW MARINAL SEAS LARGE MARGINS MID-ATLANTIC RIDGE MOSTLY UNDERWATER MOUNTAIN RANGE SOME PEAKS RISE ABOVE SEA LEVEL TO FORM ISLANDS MANY BARRIER ISLANDS INCLUDING THE LONGEST S. PADRE Oceans of the World
OCEANS OF THE WORLD INDIAN SMALLEST OF THE LARGER OCEANS AVG DEPTH 13,000 FT ALMOST COMPLETELY IN THE S. HEMISPHERE 3 OF THE WORLDS LARGEST RIVERS DUMP INTO THE NORTH INDIAN CONTRIBUTES TO HIGH LEVELS OF SEDIMENT AND FRESHWATER IN THE OCEAN Oceans of the World
SOUTHERN NEWEST OCEAN AVG DEPTH 13,100 FT OCEANS OF THE WORLD ONLY OCEAN THAT COVERS A FULL 360 OCEAN IS SEPARATE FROM BORDERING OCEANS DUE TO ANTARTIC CIRCUMPOLAR CURRENT YOUNGEST OCEAN GEOLOGICALLY SPEAKING Oceans of the World
ARCTIC SMALLEST OCEAN AVG DEPTH 3,500 FT UNIQUE BECAUSE IT IS ALMOST COMPLETELY SURROUNDED BY LAND COVERED IN ICE MOST OF THE YEAR ONLY 2% OF THE WORLD S OCEAN WATER OCEANS OF THE WORLD Oceans of the World