Lifestages of Hawai i Volcanoes Shield-Building, Declining, and Rejuvenated Volcanoes
Topics Shield-Building Stage Declining Stage Rejuvenation Stage
Topics Shield-Building Stage Declining Stage Rejuvenation Stage
Shield-Building Stage Growth of a Shield Volcano
Lifestages
Lifestages Three primary lifestages of Hawai i shield volcanoes:
Lifestages Three primary lifestages of Hawai i shield volcanoes: 1. Shield-building stage
Lifestages Three primary lifestages of Hawai i shield volcanoes: 1. Shield-building stage 2. Declining stage
Lifestages Three primary lifestages of Hawai i shield volcanoes: 1. Shield-building stage 2. Declining stage 3. Rejuvenation stage
Shield-Building Stage
Shield-Building Stage Shield-building stage is divided into two phases:
Shield-Building Stage Shield-building stage is divided into two phases: Submarine shield-building
Shield-Building Stage Shield-building stage is divided into two phases: Submarine shield-building Subaerial shield-building
Submarine Shield-Building
Submarine Shield-Building Lo ihi is in the submarine shield-building stage
Submarine Shield-Building Lo ihi is in the submarine shield-building stage
Submarine Shield-Building Lo ihi is in the submarine shield-building stage Lo ihi
Submarine Shield-Building
Submarine Shield-Building Initially erupt alkalic pillow basalts
Submarine Shield-Building Initially erupt alkalic pillow basalts Alkalic basalts are richer in Na and K, compared to Ca
Submarine Shield-Building Initially erupt alkalic pillow basalts Alkalic basalts are richer in Na and K, compared to Ca Lo ihi has a caldera
Submarine Shield-Building Initially erupt alkalic pillow basalts Alkalic basalts are richer in Na and K, compared to Ca Lo ihi has a caldera Caldera can form during any phase of the shield-building stage
Submarine Shield-Building
Submarine Shield-Building Lo ihi
Submarine Shield-Building
Submarine Shield-Building Under the weight of 5 km of water, the alkalic pillow basalts are very dense with no vesicle formation
Submarine Shield-Building Under the weight of 5 km of water, the alkalic pillow basalts are very dense with no vesicle formation In the latter part of submarine shield-building, the magma becomes tholeiitic
Submarine Shield-Building Under the weight of 5 km of water, the alkalic pillow basalts are very dense with no vesicle formation In the latter part of submarine shield-building, the magma becomes tholeiitic Tholeiitic basalt - most common type of basalt
Submarine Shield-Building Under the weight of 5 km of water, the alkalic pillow basalts are very dense with no vesicle formation In the latter part of submarine shield-building, the magma becomes tholeiitic Tholeiitic basalt - most common type of basalt Tholeiitic basalts are richer in Ca compared to Na and K
Submarine Shield-Building
Submarine Shield-Building Once the volcano reaches depths shallower than 2.5 km, small gas bubbles form
Submarine Shield-Building Once the volcano reaches depths shallower than 2.5 km, small gas bubbles form Within a few hundred meters of the surface, eruptions are explosive and result in the formation of hyaloclastitic material
Submarine Shield-Building Once the volcano reaches depths shallower than 2.5 km, small gas bubbles form Within a few hundred meters of the surface, eruptions are explosive and result in the formation of hyaloclastitic material Hyaloclastic material - loose, angular, glassy rubble
Submarine Shield-Building Once the volcano reaches depths shallower than 2.5 km, small gas bubbles form Within a few hundred meters of the surface, eruptions are explosive and result in the formation of hyaloclastitic material Hyaloclastic material - loose, angular, glassy rubble Landslides of the unconsolidated hyaloclastic material maintain steep submarine slopes
Subaerial Shield-Building
Subaerial Shield-Building Once the volcano protrudes above sea level, tholeiitic basalt flows form the subaerial portion of the shield volcano
Subaerial Shield-Building Once the volcano protrudes above sea level, tholeiitic basalt flows form the subaerial portion of the shield volcano However, the low viscosity lava commonly reaches the shoreline, producing hyaloclastites and maintaining steep subaerial slopes
Subaerial Shield-Building Once the volcano protrudes above sea level, tholeiitic basalt flows form the subaerial portion of the shield volcano However, the low viscosity lava commonly reaches the shoreline, producing hyaloclastites and maintaining steep subaerial slopes Caldera repeatedly collapses and refills
Shield-building stage - Mauna Loa
Steep Submarine Slopes
Hawai i Submarine Slopes
Steep Submarine Slopes Hawai i
O ahu
Subaerial Shield-Building
Subaerial Shield-Building Kilauea and Mauna Loa are subaerial shield-building volcanoes
Subaerial Shield-Building Kilauea and Mauna Loa are subaerial shield-building volcanoes As a shield volcano drifts away from the center of the hot spot:
Subaerial Shield-Building Kilauea and Mauna Loa are subaerial shield-building volcanoes As a shield volcano drifts away from the center of the hot spot: the magma supply diminishes
Subaerial Shield-Building Kilauea and Mauna Loa are subaerial shield-building volcanoes As a shield volcano drifts away from the center of the hot spot: the magma supply diminishes eruptions become less frequent
Subaerial Shield-Building Kilauea and Mauna Loa are subaerial shield-building volcanoes As a shield volcano drifts away from the center of the hot spot: the magma supply diminishes eruptions become less frequent magma stays in magma chamber longer and differentiates
Subaerial Shield-Building Kilauea and Mauna Loa are subaerial shield-building volcanoes As a shield volcano drifts away from the center of the hot spot: the magma supply diminishes eruptions become less frequent magma stays in magma chamber longer and differentiates Differentiated lavas signal the end of the shield-building stage
Differentiation
Bowen s Reaction Series
Next Declining Stage