GEOPSEA EXAM 1 Flashcards
The major kinematic reorganization of the Pacific Plate at around 43 Ma involves _ rotation with respect to hotspots.
50 degrees clockwise
The absolute velocity of the Pacific plate is:
80 mm/yr
The Pacific plate subducts under the Philippine Sea Plate along:
Bonin-Marianas-Yap trench system
The deepest trench in this planet is:
Marianas trench
The submarine plateaus in the West Philippine Basin are:
benham rise, urdaneta plateau, oki-daito ridges
the trend of the Central Basin Fault is
WNW-ESE
The opening of the Parece Vela-Shikoku and the Marianas Basin involves what mechanism?
retreat of subducting slab
The Palau-Kyushu Ridge separates which two basins?
parece vela-shikoku and west philippine basin
this ridge splits into two branches towards the south as the West and East Marianas Ridges:
Izu-Bonin Ridge
Which of the following volcanic arcs is presently active?
East mariana ridge
The Philippine Sea Plate/Eurasia rotation pole is located
NE of Japan
The relative displacement rate of Philippine Sea Plate and Eurasia is:
7.0 cm/yr
The directional change of the Philippine Sea Plate between 4 and 6 Ma involves_rotation
45 degrees counterclockwise
Which of the following collision zones involves arc-continent interaction?
-taiwan
-moluccas
-philippine trench
-east luzon trough
Taiwan
The Sulu-Zamboanga Arc separates:
Sulu Sea and Celebes Sea
A back-arc basin is formed:
behind a subduction zone
Which of the following oceanic basins have been studied as an example of a trapped basin?
-south china sea
-marianas
-parece vela-shikoku
-west philippine basin
west philippine basin
The term Philippine Mobile Belt was first defined by which author?
Gervasio
Which of the following DOES NOT indicate that the Philippine trench is young?
-deep Benioff zone
-well developed accretionary prism
-southern termination poorly known
-none of the above
deep Benioff zone
This is the morphologic expression of the subduction of the oceanic crust of the South China Sea under the Luzon arc
Manila Trench
This fault links the Cotabato Trench with the Negros Trench
Cotabato Trench
In which of the following islands are pre-Cretaceous metamorphic rocks NOT likely to be found?
-north palawan
-mindoro
-panay
-davao oriental
Davao Oriental
The collision of the Halmahera and Sangihe is an example of:
arc-arc collision
The islands in the Philippine Mobile Belt originated from
sub-equatorial regions
The following are pre-Cretaceous metamorphic rocks, EXCEPT:
-Caramay Schist
-Halcon Metamorphic COmplex
-Tungauan Schist
-none of the above
none of the above
The age of ophiolitic rocks is based on the age of the:
a. pillow basalts
b. pelagic sediments
c. sheeted dikes
d. layered gabbro
b. pelagic sediments
The oldest known magmatic rocks in the Philippines are found in Cebu Island. This rock is a
Diorite
The Aroroy Diorite is an intrusive body found in
Masbate
This is an intrusive body found in the island of Panay
Sara Diorite
Mount Apo, was proposed to have formed from:
partial melting of detached slab
Bud Dajo is an active volcano in
Sulu
Which of the following sedimentary basins is not traversed by the Philippine Fault:
-southern luzon-bicol basin
-mindoro basin
-agusan-davao basin
-ilocos-central luzon basin
mindoro basin
The Philippine Fault was designated by various terms by different authors. One of which is Repetti, who named this fault as:
Master Fault
What is the mode of displacement of the Philippine Fault?
Left-Lateral
The March 17, 1973 southern Luzon earthquake, of the Philippine Fault, had an epicenter located in
Ragang Gulf
The northern segment of the Philippine Fault is characterized by:
transpressional regime
This feature corresponds to the NNE-SSW alignment of active volcanoes such as Taal, Banahaw, Makiling, and maars of Laguna province.
Macolod Corridor
Which of the following faults is characterized by normal faulting?
-sindangan fault
-cotabato fault
-tablas lineament
-legaspi lineament
cotabato fault
This fault is a tectonic boundary between the Palawan-Mindoro microcontinental block and western edge of the Philippine Mobile Belt
Tablas Lineament
The Tablas Lineament is characterized by what type of displacement?
right-lateral
the basement rock of the Southern Pacific Cordillera is the
Barcelona Formation
This constitutes the basement rocks of the Central Pacific Cordillera. It is characterized by andesitic flows and pyroclastic basement believed to be of Eocene age?/
Anoling Andesite
This unit refers to the Holocene volcanic deposits of Lake Leonard in Davao. This volcanic activity is manifested as domes, plugs, flows and pyroclastic rocks of andesitic to dacitic composition
Amacan Volcano Complex
This formation was named by San Jose Oil Company for the exposures along a river in Prosperidad, Agusan del Sur. An angular unconformity separates this from the underlying formation.
Wawa Formation
This represents the well-defined rhythmic interbeds of indurated thin sandstones and shales of Early Miocene age in the core of the Kilagden Anticline of Asuncion, Davao del Norte
Kabagtican Formation
At 50 Ma, there was a south-dipping subduction north of the Philippine Sea Plate which is the _ . Its subduction may have driven the spreading of the West Philippine Sea.
Northern New Guinea Plate
In the plate reconstruction by Hall, during which time did the Palawan-Mindoro microcontinent start rifting from the eastern edge of the Eurasian Plate?
35 Ma
Which of the following significant events happened 5 Ma ago?
Luzon arc came into collision with Taiwan
Spreading in the West Philippine-Celebes Sea basin had ceased:
30 Ma ago
The East Philippine Arc was formed by the subduction of _ under _ .
Indo-Australian plate, proto-South China Sea
