PRC Geologist Licensure Examination (Philippines)

Which plate tectonic feature bounds the eastern margin of the Philippine Mobile Belt, representing the subduction of the Philippine Sea Plate?

• AManila Trench
• BPhilippine Trench
• CCotabato Trench
• DSulu Trench

The Manila Trench is characterized by which of the following tectonic configurations?

• AEastward subduction of the Eurasian Plate beneath the Philippine Mobile Belt
• BWestward subduction of the Philippine Sea Plate beneath the Eurasian Plate
• CLeft-lateral transform motion between Luzon and Taiwan
• DContinental collision between the Palawan Block and Mindoro

What is the total approximate length and dominant sense of motion of the Philippine Fault Zone (PFZ)?

• A500 km, right-lateral strike-slip
• B1,200 km, left-lateral strike-slip
• C800 km, normal dip-slip
• D1,500 km, right-lateral strike-slip

Which ophiolite complex in the Philippines represents one of the most complete and widely studied slice of ancient oceanic lithosphere in the western Pacific?

• AAngat Ophiolite
• BZambales Ophiolite Complex
• CAntique Ophiolite
• DLeyte Ophiolite

In the geologic time scale, which of the following is a geochronologic unit rather than a chronostratigraphic unit?

• ASystem
• BPeriod
• CErathem
• DSeries

Which stratigraphic principle states that in an undisturbed sequence of sedimentary rocks, each layer is older than the one above it and younger than the one below it?

• APrinciple of Original Horizontality
• BPrinciple of Superposition
• CPrinciple of Lateral Continuity
• DPrinciple of Cross-Cutting Relationships

What type of unconformity is characterized by an erosion surface separating younger horizontal sedimentary strata from older, tilted or folded sedimentary rocks?

• ADisconformity
• BAngular Unconformity
• CNonconformity
• DParaconformity

Which of the following defines the 'strike' of a planar geological feature, such as a fault or bedding plane?

• AThe angle of inclination measured from the horizontal plane
• BThe compass direction of a line formed by the intersection of a dipping plane with a hori…
• CThe direction perpendicular to the dip direction pointing downward
• DThe angle between magnetic north and true north

A thrust fault is structurally defined as which of the following?

• AA high-angle normal fault with dip greater than 45 degrees
• BA low-angle reverse fault with a dip of 45 degrees or less
• CA strike-slip fault with horizontal displacement
• DA fault where the hanging wall moves downward relative to the footwall

If a fold has its youngest strata exposed in the center (core) of the structure and its limbs dip inward toward the hinge line, the fold is classified as a/an:

• AAnticline
• BSyncline
• CMonocline
• DDome

Which type of drainage pattern typically develops in regions underlain by alternating bands of resistant and weak rocks that have been tilted or folded, characterized by primary streams flowing parallel to the strike and tributaries joining at right angles?

• ADendritic drainage
• BTrellis drainage
• CRadial drainage
• DRectangular drainage

Which chemical weathering process involves the reaction of minerals with water to form new minerals, such as the alteration of orthoclase feldspar into kaolinite clay?

• AOxidation
• BHydrolysis
• CDissolution
• DHydration

The formation of karst topography, including sinkholes and caves, is primarily driven by the chemical dissolution of limestone. Which acid is the main agent responsible for this dissolution in nature?

• ASulfuric acid
• BCarbonic acid
• CHydrochloric acid
• DNitric acid

In glacial geomorphology, a long, sinuous ridge composed of stratified sand and gravel deposited by a subglacial stream flowing beneath a melting glacier is called a/an:

• AKame
• BEsker
• CDrumlin
• DMoraine

What is the primary factor that distinguishes 'creep' from other types of mass wasting, such as rockslides or debris flows?

• AThe presence of water as a lubricant
• BThe extremely slow, imperceptible rate of downslope movement
• CThe angle of the slope on which it occurs
• DThe type of material involved (consolidated rock vs. soil)

Which plate tectonic force is widely considered the dominant driver of lithospheric plate motion, generated by the gravitational sinking of cold, dense oceanic slabs into the mantle?

• ARidge push
• BSlab pull
• CBasal drag
• DMantle shearing

In the Wilson Cycle, which describes the lifecycle of ocean basins, which stage is characterized by the initiation of continental rifting and the formation of a rift valley?

• AJuvenile stage
• BEmbryonic stage
• CMature stage
• DDeclining stage

The Mohorovicic discontinuity (Moho) represents the boundary between which two layers of the Earth?

• ALithosphere and Asthenosphere
• BCrust and Mantle
• CUpper Mantle and Lower Mantle
• DOuter Core and Inner Core

Which of the following is a characteristic of S-waves (secondary waves) generated by earthquakes?

• AThey are longitudinal waves that compress and dilate the rock.
• BThey are transverse waves that can propagate only through solid materials.
• CThey are the fastest seismic waves and arrive first at recording stations.
• DThey can travel through the Earth's liquid outer core.

The S-wave shadow zone, where no direct S-waves are recorded at seismograph stations, is located at what angular distance from an earthquake's epicenter?

• ABetween 103° and 143°
• BBeyond 103° (from 103° to 180°)
• COnly at 180° directly opposite the epicenter
• DBetween 0° and 103°

Which magma generation mechanism is primarily responsible for the volcanism observed at mid-ocean ridges and rift zones?

• AFlux melting (addition of volatiles)
• BDecompression melting
• CHeat transfer melting
• DFriction melting

What type of magmatism is typical of island arc settings, such as the majority of the Philippine Mobile Belt?

• ATholeiitic basaltic magma from anhydrous decompression melting
• BCalc-alkaline magma generated by flux melting of the mantle wedge
• CAlkaline basaltic magma derived from deep mantle plumes
• DUltra-felsic rhyolitic magma from crustal anatexis

In Bowen's Reaction Series, which mineral is the first to crystallize in the discontinuous branch as magma cools?

• AQuartz
• BOlivine
• CBiotite mica
• DPyroxene

Tectonically, the Philippine archipelago is divided into two distinct blocks. What are these blocks?

• AThe Marianas Block and the Sundaland Block
• BThe Palawan Microcontinental Block and the Philippine Mobile Belt
• CThe Luzon Arc and the Mindanao Trench Block
• DThe Eurasian Plate Block and the Philippine Sea Plate Block

Which region in the Philippines is considered part of the Palawan Microcontinental Block, exhibiting continental crustal affinity and rock sequences similar to southeastern China?

• ABicol Peninsula
• BNorthern Palawan (including Calamian Islands and Mindoro)
• CEastern Mindanao
• DZambales Peninsula

In structural geology, what is the 'rake' (or pitch) of a lineation on a dipping geologic plane?

• AThe angle between the horizontal strike line and the lineation, measured on the plane its…
• BThe vertical angle between the lineation and the horizontal plane
• CThe compass direction of the horizontal projection of the lineation
• DThe angle of dip of the fault plane containing the lineation

According to the strain ellipsoid model of deformation, in which direction relative to the maximum principal compressive stress (sigma 1) do conjugate shear fractures typically form?

• AParallel to sigma 1 (at 0 degrees)
• BAt approximately 30 degrees to sigma 1
• CPerpendicular to sigma 1 (at 90 degrees)
• DAt approximately 45 degrees to sigma 1

What is the key structural distinction between a transform fault and a transcurrent fault?

• ATransform faults are left-lateral while transcurrent faults are right-lateral.
• BTransform faults terminate abruptly at plate boundaries, whereas transcurrent faults die…
• CTransform faults are only normal faults while transcurrent faults are strike-slip.
• DTransform faults occur only in continental crust, while transcurrent faults occur only in…

In subduction zone tectonics, a chaotic mixture of highly deformed rocks of diverse origins (such as pelagic sediments, volcanic rocks, and serpentinized mantle) embedded in a sheared argillaceous matrix is termed a/an:

• AOlistostrome
• BMelange
• CTurbidite
• DBreccia

Which stratigraphic correlation method relies on matching rock layers based on their lithological characteristics, such as mineral composition, grain size, and color?

• ABiostratigraphy
• BLithostratigraphy
• CChronostratigraphy
• DSequence Stratigraphy

Which of the following describes the ideal characteristics of an index fossil used for biostratigraphic correlation?

• ALong geologic range, restricted geographic distribution, and rare occurrence
• BShort geologic range, wide geographic distribution, and high abundance
• COccurs only in one specific type of sedimentary rock (facies-dependent)
• DFossilized remains of large land mammals only

The most recent ice ages, characterized by major continental glaciations and cycles of glacial-interglacial periods, occurred during which geological epoch?

• AMiocene
• BPleistocene
• CPliocene
• DHolocene

What is the practical upper age limit for radiocarbon (Carbon-14) dating of organic materials?

• AApproximately 5,000 years
• BApproximately 50,000 to 60,000 years
• CApproximately 500,000 years
• DNo upper limit; it can date Paleozoic coals

On a standard geological map, how is the dip direction indicated relative to the strike line in the map symbol for bedding?

• AA longer line parallel to the strike line
• BA short tick mark attached at a right angle (90 degrees) to the strike line
• CA circle enclosing the strike line
• DAn arrow pointing at 45 degrees to the strike line

Which of the following correctly describes the relationship between the true dip angle and the apparent dip angle of a planar geological bed?

• AApparent dip angle is always greater than true dip angle.
• BApparent dip angle is always less than or equal to true dip angle.
• CApparent dip angle is always equal to true dip angle.
• DThere is no mathematical relationship between the two.

According to the geological 'Rule of V's' for mapping, if a planar bed has a dip direction pointing upstream (opposite to the direction of valley gradient), the outcrop pattern of the bed as it crosses a river valley will form a 'V' shape that points:

• ADownstream (in the direction of flow)
• BUpstream (opposite to the direction of flow)
• CParallel to the river channel
• DIt will not form a V shape

In rock mechanics, what is the fundamental difference between stress and strain?

• AStress is the amount of deformation, while strain is the force applied.
• BStress is force per unit area acting on a rock, while strain is the resulting change in s…
• CStress occurs only under compression, while strain occurs only under tension.
• DStress is a vector quantity, while strain is a scalar quantity.

Which seismic theory, proposed by Harry Fielding Reid after the 1906 San Francisco earthquake, explains how energy is stored in rocks and suddenly released to generate an earthquake?

• APlate Tectonic Theory
• BElastic Rebound Theory
• CDilatancy-Diffusion Theory
• DSeismic Gap Theory

What is the difference between the hypocenter and the epicenter of an earthquake?

• AThe hypocenter is on the surface, while the epicenter is directly below it in the mantle.
• BThe hypocenter is the actual point of rupture within the Earth, while the epicenter is th…
• CThe hypocenter measures the earthquake magnitude, while the epicenter measures intensity.
• DThey are synonymous terms for the location where the fault rupture terminates.

Which model of isostasy assumes that the Earth's crust has a constant density but varies in thickness, with higher mountains having deeper crustal roots sinking into the mantle?

• APratt Model
• BAiry Model
• CVening Meinesz Model
• DArchimedes Model

According to Bragg's Law, which is fundamental to X-ray diffraction (XRD) mineral analysis, what is the correct mathematical relationship for constructive interference of X-rays?

• An\lambda = d \sin\theta
• Bn\lambda = 2d \sin\theta
• Cn\lambda = d \cos\theta
• Dn\lambda = 2d \tan\theta

A mineral crystallizes with three unequal crystallographic axes, where two axes intersect at right angles (90 degrees) and the third axis is inclined (not 90 degrees). To which crystal system does this mineral belong?

• ATriclinic
• BMonoclinic
• COrthorhombic
• DTetragonal

In the Mohs hardness scale, which of the following mineral pairs has hardness values of 3 and 4, respectively?

• AGypsum and Calcite
• BCalcite and Fluorite
• CFluorite and Apatite
• DApatite and Orthoclase

Mica minerals, such as muscovite and biotite, exhibit which characteristic cleavage pattern?

• ATwo directions of cleavage intersecting at 90 degrees
• BOne direction of perfect cleavage (basal cleavage)
• CThree directions of cleavage forming a rhombohedral shape
• DThree directions of cleavage intersecting at 90 degrees (cubic cleavage)

Which silicate mineral group is characterized by a double-chain structure of silicon-oxygen tetrahedra, with a characteristic cleavage angle of approximately 56 and 124 degrees?

• APyroxene group
• BAmphibole group
• CMica group
• DFeldspar group

The plagioclase feldspar group is a classic example of a solid solution series. What are the two endmember minerals of this series?

• AOrthoclase and Albite
• BAlbite and Anorthite
• CForsterite and Fayalite
• DQuartz and Orthoclase

Which diagnostic physical property is most useful for identifying quartz in hand specimens, distinguishing it from minerals like calcite or feldspar?

• APerfect cubic cleavage and high density
• BConchoidal fracture and lack of cleavage
• CVigorous effervescence when tested with dilute hydrochloric acid
• DStriations on cleavage planes and a hardness of 6