basin ocean floor
DESCRIPTION
BASIN OCEAN FLOOR. Objectives At the end of the lesson the students are expected to: i dentify the major features of the Ocean Basin Floor and the Oceanic Ridge l abel the features of the Ocean Floor List and describe the three types of Seafloor Sediment . - PowerPoint PPT PresentationTRANSCRIPT
BASIN OCEAN FLOOR
ObjectivesAt the end of the lesson the students
are expected to:
• identify the major features of the Ocean Basin Floor and the Oceanic Ridge
• label the features of the Ocean Floor
• List and describe the three types of Seafloor Sediment
The OCEAN BASIN FLOOR lies between the continental margin and the oceanic ridge.
Ocean Basin Floor
o Deep-ocean trenches
o Abyssal plains o Seamounts
DEEP-OCEAN TRENCHES are long, relatively narrow creases in the seafloor that form the deepest parts of the ocean
volcanic island arc- arc shaped row of active volcanoes
Challenger Deep(Mariana Trench)
- the deepest known part of the world ocean
ABYSSAL PLAINS are deep, incredibly flat features. These regions are likely the most level places on Earth.
SEAMOUNTS are isolated volcanic peaks which may rise hundreds of meters above the surrounding topography.
Some are formed as a result of hot spots while others may form near oceanic ridges
Volcanic islands in the Atlantic1. Azores2. Ascension3. Tristan da Cunha4. St. Helena
GUYOTS or TABLEMOUNTS are submerged, flat-topped seamounts.
MID-OCEAN RIDGE
Oceanic ridge or Mid-Ocean ridgeIs topographically elevated feature that is found near the center of the most ocean basins.
It is characterized by extensive faulting and numerous volcanic structures that have developed on the newly formed crust.
Mid-Ocean Ridge
SEAFLOOR SEDIMENTS
TERRIGENOUS SEDIMENTSBIOGENOUS SEDIMENTSHYDROGENOUS SEDIMENTS
TERRIGENOUS SEDIMENTS
oconsist primarily of mineral grains that were weathered from continental rocks
oaccumulates slowly (5000-50,000yrs to deposit 1cm abyssal clay layer
ocolor may be red or brown
BIOGENOUS SEDIMENTS
Biological origin- primarily shells and skeletons of marine animals and algae.
Types of Biogenous sediments
oCalcareous oozes-remains of foraminifera and coccolithophores
-may form chalkoSiliceous oozes-remains of radiolarians and diatomsoPhosphate-rich materials-from bones, teeth and scales of fish
HYDROGENOUS SEDIMENTS
Consist of minerals that crystallize directly from seawater through various chemical reactions
maa
Thank You!!!!!!