Types of Rocks (Igneous Rocks) questions

In the continuous reaction of Bowen's reaction series, the first mineral to crystallize from the melt is ..........

1. A olivine
2. B potassium feldspar
3. C calcium feldspar
4. D sodium feldspar

Which of the following rocks is the last to crystallize from lava?

1. A Peridotite
2. B Gabbro
3. C Andesite
4. D Rhyolite

The last of the following minerals to crystallize in the discontinuous reaction of Bowen's reaction series is ..........

1. A amphibole
2. B biotite
3. C quartz
4. D olivine

By studying the two opposite graphs (A) and (B), we conclude that (Y) may represent ..........

1. A the melting temperature
2. B the percentage of magnesium
3. C the percentage of iron
4. D the percentage of potassium

The highest percentage of iron is found in the minerals ..........

1. A olivine and quartz
2. B amphibole and muscovite
3. C olivine and pyroxene
4. D amphibole and orthoclase

The opposite mineral, which forms from the crystallization of the elements of magma, belongs to the group of ..........

1. A carbonates
2. B sulfides
3. C sulfates
4. D silicates

Olivine and pyroxene crystals formed as a result of ..........

1. A the cooling of acidic melt
2. B the cooling of acidic lava
3. C the cooling of basic magma
4. D the cooling of intermediate lava

As the temperature of the melt decreases ..........

1. A the percentage of iron increases and the percentage of silicon decreases
2. B the percentage of magnesium decreases and the percentage of sodium increases
3. C the percentage of magnesium decreases and the percentage of potassium decreases
4. D the percentage of calcium increases and the percentage of magnesium decreases

From your study of Bowen's reaction series, we find that ..........

1. A most minerals crystallize at the same temperature
2. B most minerals of acidic rocks crystallize before the minerals of basic rocks
3. C muscovite and quartz are the last minerals to crystallize when magma cools
4. D biotite is the first mineral to crystallize when magma cools

The opposite figure shows a sample of an intermediate igneous rock. Which of the following minerals is rarely found in this rock sample?

1. A Amphibole
2. B Quartz
3. C Olivine
4. D Pyroxene

When two thirds of the melt have crystallized, the remaining melt contains a very small percentage of the element ..........

1. A calcium
2. B silicon
3. C sodium
4. D potassium

Compared to the chemical composition of the feldspar in acidic rocks, the feldspar in basic rocks is ..........

1. A rich in calcium, sodium and potassium
2. B rich in calcium and poor in sodium and potassium
3. C poor in calcium and rich in sodium and potassium
4. D poor in calcium, sodium and potassium

Which of the following minerals crystallizes first from basic magma?

1. A Amphibole
2. B Pyroxene
3. C Orthoclase
4. D Biotite

The opposite graph shows the relation between the crystallization temperature and the concentration of an element in igneous rocks. The two elements (X) and (Y) may respectively be ..........

1. A (X) iron / (Y) potassium
2. B (X) iron / (Y) magnesium
3. C (X) potassium / (Y) iron
4. D (X) magnesium / (Y) iron

The opposite figure shows the crystallization conditions of a group of igneous rocks. Which of the following choices is correct about the types of crystallized rocks?

1. A (A) komatiite - (B) granite
2. B (C) granite - (D) diorite
3. C (A) komatiite - (X) andesite
4. D (B) rhyolite - (Y) diorite

The following table shows the percentages of some minerals in four samples of igneous rocks. Study it well, then answer:
Which of the following letters represents ultrabasic igneous rocks?

1. A W
2. B X
3. C Y
4. D Z

The following table shows the percentages of some minerals in four samples of igneous rocks. Study it well, then answer:
Which of the following may represent diorite?

1. A W
2. B X
3. C Y
4. D Z

Which of the following choices represents the correct relation between an igneous rock and its most abundant element?

1. A Granite - calcium
2. B Komatiite - magnesium
3. C Rhyolite - iron
4. D Basalt - potassium

We have 3 samples of igneous rocks arranged as follows (komatiite, then basalt, then andesite). These samples are arranged ..........

1. A in descending order of iron percentage
2. B in descending order of cooling rate
3. C in ascending order of crystallization temperature
4. D in ascending order of calcium percentage

If you have 4 rock samples arranged as follows: (obsidian, then andesite, then dolerite, then peridotite), this order is ascending according to ..........

1. A the number of crystals, and descending according to the silica percentage
2. B the silica percentage, and descending according to the number of crystals
3. C the percentage of iron and magnesium, and descending according to the sodium percentage
4. D the potassium percentage, and descending according to the specific gravity

The opposite sample shows an igneous rock with a .......... texture.

1. A fine texture with air holes
2. B fragmental texture of sharp-edged grains
3. C fragmental texture of rounded grains
4. D foliated texture with air holes

Granite is classified as a plutonic igneous rock because it ..........

1. A is rich in quartz and feldspar
2. B is coarse-grained with large crystals
3. C crystallizes from cooling lava
4. D is very hard and light in colour

Which of the following characterizes a rock formed when a melt loses its heat very quickly while forming crystals?

1. A Large crystal size
2. B A higher iron percentage
3. C A higher potassium percentage
4. D A larger number of crystals

A melt made of 5 main mineral families, when it crystallizes inside the Earth's crust in two stages, forms the rock ..........

1. A granite
2. B microdiorite
3. C dolerite
4. D peridotite

When basic lava cools, the rock .......... crystallizes.

1. A gabbro
2. B basalt
3. C andesite
4. D rhyolite

When intermediate magma cools, the rock .......... may form.

1. A gabbro
2. B granite
3. C diorite
4. D pumice

The first mineral to melt in granite when it is exposed to very high heat is ..........

1. A quartz
2. B feldspar
3. C mica
4. D amphibole

The two opposite samples (A) and (B) represent two types of igneous rocks. The two rocks are probably ..........

1. A (A) gabbro, (B) dolerite
2. B (A) granite, (B) rhyolite
3. C (A) gabbro, (B) rhyolite
4. D (A) granite, (B) dolerite

The opposite figure shows the formation of basalt from a melt that crystallized ..........

1. A slowly, forming minerals rich in calcium
2. B slowly, forming minerals rich in potassium
3. C quickly, forming minerals rich in sodium
4. D quickly, forming minerals rich in iron

The rock that contains some large crystals among other fine crystals, of the following, is ..........

1. A microgranite
2. B gabbro
3. C granite
4. D andesite

The rocks rich in quartz and orthoclase are ..........

1. A granite and gabbro
2. B gabbro and basalt
3. C basalt and rhyolite
4. D rhyolite and granite

The property that gives the best evidence that granite crystallized at great depths below the Earth's surface is ..........

1. A its low density
2. B its chemical composition
3. C the acidity of its minerals
4. D its coarse texture

Gabbro is an igneous rock that most probably formed from a melt that underwent ..........

1. A fast cooling at the Earth's surface
2. B slow cooling at the Earth's surface
3. C fast cooling at great depths below the Earth's surface
4. D slow cooling at great depths below the Earth's surface

The extrusive igneous rock with a silica percentage of about 70 % is ..........

1. A granite
2. B rhyolite
3. C microgranite
4. D dolerite

Basalt has a dark black colour because of the high percentage of ..........

1. A potassium
2. B silica
3. C iron
4. D sodium

Which of the following rocks contains a small percentage of quartz crystals visible to the naked eye?

1. A Acidic volcanic
2. B Acidic plutonic
3. C Intermediate plutonic
4. D Basic volcanic

A rock with clear crystals made of feldspar, olivine, pyroxene and amphibole is ..........

1. A peridotite
2. B gabbro
3. C granite
4. D basalt

Here are hand samples of an igneous rock. What are the type and the cooling rate of this rock?

1. A Plutonic, slow cooling
2. B Plutonic, fast cooling
3. C Volcanic, slow cooling
4. D Volcanic, fast cooling

The crystallization of a melt at a low temperature forms a rock that is ..........

1. A dark and poor in potassium
2. B dark and rich in quartz
3. C light-coloured and rich in silica
4. D light-coloured and poor in sodium

The two opposite igneous rocks are alike in ..........

1. A the place of crystallization
2. B the silica percentage
3. C the crystallization temperature
4. D the calcium percentage

The most accurate statement explaining why olivine is not one of the main mineral components of granite is that olivine crystallizes ..........

1. A at a low temperature, while the minerals of granite crystallize at a high temperature
2. B at a high temperature, while the minerals of granite crystallize at a low temperature
3. C only in volcanic rocks, while granite is a plutonic igneous rock
4. D only in intermediate rocks, while granite is an acidic igneous rock

The rocks that form volcanic islands in the oceanic crust are usually made of ..........

1. A fine crystals from an acidic melt
2. B fine crystals from a basic melt
3. C coarse crystals from an acidic melt
4. D coarse crystals from a basic melt

The opposite figure shows a light-coloured igneous rock (B) cut through by a dark igneous rock (A). This fine-grained, light-coloured igneous rock is ..........

1. A rhyolite
2. B diorite
3. C basalt
4. D gabbro

Granite is very poor in iron because ..........

1. A it crystallizes inside the Earth
2. B its minerals crystallize at low temperatures
3. C it is a basic rock
4. D its minerals crystallize at high temperatures

Quartz, biotite and amphibole crystals formed mainly as a result of ..........

1. A chemical reactions between elements in sea water
2. B the cooling and crystallization of a melt
3. C the deposition of sediments by wind
4. D the cementation of lake sediments

The rock formed by the crystallization of a melt with 60 % silica within the surrounding rocks is ..........

1. A dolerite
2. B diorite
3. C microdiorite
4. D andesite

When iron-rich lava cools, the rock .......... may form.

1. A komatiite
2. B andesite
3. C peridotite
4. D rhyolite

The opposite rock sample represents a rock with a silica percentage of about ..........

1. A 72 %
2. B 52 %
3. C 48 %
4. D 43 %

The process that leads to the formation of rhyolite is ..........

1. A the deposition of transported fragments on the sea floor
2. B the metamorphism of rocks due to pressure and heat
3. C the cooling of magma inside the Earth
4. D the eruption of lava from a volcano and its crystallization

The extrusive igneous rock that crystallizes at temperatures below 750 °C is ..........

1. A pumice
2. B andesite
3. C basalt
4. D peridotite

The light pink intrusive igneous rock is ..........

1. A granite
2. B microgranite
3. C rhyolite
4. D dolerite

In the opposite figure, hypabyssal rocks are represented by the letters (A), (B), (C) and (D). Which of the following represents these rocks?

1. A (A) peridotite - (B) gabbro - (C) diorite - (D) granite
2. B (A) gabbro - (B) komatiite - (C) diorite - (D) rhyolite
3. C (A) komatiite - (B) basalt - (C) andesite - (D) rhyolite
4. D (A) granite - (B) diorite - (C) dolerite - (D) peridotite

The sudden contact of a melt with sea water may lead to the formation of the rock ..........

1. A granite
2. B basalt
3. C dolerite
4. D peridotite

The opposite sample represents a mineral found in rhyolite; one of its properties is that it splits easily in one direction. This mineral ..........

1. A crystallizes at a temperature of about 780 °C
2. B belongs to the group of native (elemental) minerals
3. C crystallizes at a temperature of about 1200 °C
4. D is rich in sodium and calcium

The most abundant mineral in peridotite, of the following, is ..........

1. A olivine
2. B mica
3. C amphibole
4. D calcium plagioclase

When lava cools, the first of the following rocks to crystallize according to Bowen's series is ..........

1. A basalt
2. B granite
3. C andesite
4. D peridotite

The temperature at which the minerals of a rock crystallize indicates all of the following except ..........

1. A the silica percentage of the rock
2. B the colour of the rock
3. C the texture of the rock
4. D the chemical composition of the rock

The highest percentage of potassium is found in the rocks ..........

1. A rhyolite and pumice
2. B granite and andesite
3. C rhyolite and andesite
4. D granite and gabbro

The correct descending order of the rocks formed by the crystallization of a melt according to the crystallization temperature is ..........

1. A basalt, then rhyolite, then granite
2. B komatiite, then rhyolite, then andesite
3. C basalt, then andesite, then rhyolite
4. D komatiite, then basalt, then gabbro

A rhyolite sample with a uniform mineral composition was divided into two samples (A) and (B), where sample (A) is half the volume of sample (B). The silica percentage in sample (A) is ..........

1. A half the silica percentage in the original rock
2. B half the silica percentage in sample (B)
3. C equal to the silica percentage in sample (B)
4. D a quarter of the silica percentage in the original rock

The equivalent of the ultrabasic volcanic rock, of the following, is ..........

1. A diorite
2. B dolerite
3. C peridotite
4. D komatiite

The rock with a porphyritic texture whose silica percentage is 45 : 55 % is ..........

1. A dolerite
2. B microgranite
3. C basalt
4. D gabbro

The mineral rarely found in basaltic volcanic cones, of the following, is ..........

1. A olivine
2. B pyroxene
3. C plagioclase
4. D muscovite

Which of the following rocks represents the opposite sample?

1. A Basalt
2. B Andesite
3. C Rhyolite
4. D Komatiite

The mineral that is part of the main composition of gabbro, diorite and rhyolite, of the following, is ..........

1. A quartz
2. B amphibole
3. C olivine
4. D orthoclase

The igneous rocks whose minerals crystallize at the highest temperatures, of the following, are the .......... rocks.

1. A acidic plutonic
2. B intermediate extrusive
3. C basic plutonic
4. D ultrabasic extrusive

The opposite graph shows the crystallization temperature of 4 different types of rocks that differ in chemical composition. If the 4 rocks are (andesite, granite, peridotite, dolerite), their correct order is ..........

1. A (1) granite / (2) andesite / (3) dolerite / (4) peridotite
2. B (1) peridotite / (2) andesite / (3) dolerite / (4) granite
3. C (1) dolerite / (2) andesite / (3) granite / (4) peridotite
4. D (1) peridotite / (2) granite / (3) andesite / (4) dolerite

We have a hand sample of dolerite. Which of the following statements suits the sample?

1. A It is made of large crystals because of the slow cooling of magma
2. B It is made of large crystals and fine ones, with 60 % silica
3. C It is made of large crystals and fine ones, with 50 % silica
4. D It is made of large crystals because of the fast cooling of magma

Biotite and muscovite are mica minerals that differ in chemical composition. Compared to the magma from which biotite forms, the magma from which muscovite forms is usually ..........

1. A more basic and less dense
2. B more acidic and less dense
3. C more basic and denser
4. D more acidic and denser

The coarse igneous rock made of about 60 % pyroxene, 25 % plagioclase, 10 % olivine and 5 % amphibole is ..........

1. A komatiite
2. B peridotite
3. C gabbro
4. D basalt

The most accurate statement of the similarity and the difference between diorite and andesite is that they ..........

1. A are alike in mineral composition and differ in silica percentage
2. B are alike in mineral composition and differ in texture
3. C are alike in silica percentage and differ in mineral composition
4. D are alike in texture and differ in mineral composition

The opposite graph shows the percentages of some minerals in two different rocks (X) and (Y) made of large crystals. Which of the following represents rocks (X) and (Y)?

1. A (X) granite - (Y) diorite
2. B (X) diorite - (Y) microgranite
3. C (X) granite - (Y) gabbro
4. D (X) rhyolite - (Y) andesite

Samples of equal volume of peridotite, diorite, granite and gabbro were dropped at the same time into a deep tank filled with water. Which of these rocks is the last to reach the bottom of the tank?

1. A Peridotite
2. B Diorite
3. C Granite
4. D Gabbro

The opposite table shows physical properties of the minerals of a plutonic igneous rock, represented by the letters (A), (B) and (C). Study it well, then answer:
The type of rock texture is ..........

1. A glassy
2. B lamellar
3. C porphyritic
4. D coarse

The opposite table shows physical properties of the minerals of a plutonic igneous rock, represented by the letters (A), (B) and (C). Study it well, then answer:
The names of minerals (A), (B) and (C) respectively are ..........

1. A (A) quartz / (B) mica / (C) orthoclase
2. B (A) orthoclase / (B) mica / (C) calcite
3. C (A) mica / (B) quartz / (C) calcite
4. D (A) orthoclase / (B) mica / (C) quartz

The opposite figure represents the mineral composition of igneous rocks. What are minerals (A), (B) and (C)?

1. A (A) olivine - (B) mica - (C) sodium feldspar
2. B (A) pyroxene - (B) amphibole - (C) quartz
3. C (A) calcium feldspar - (B) mica - (C) orthoclase
4. D (A) mica - (B) feldspar - (C) quartz

If the melt in the opposite figure has 40 % silica, when it cools and crystallizes it forms the rock ..........

1. A andesite
2. B peridotite
3. C komatiite
4. D basalt

The opposite model shows an eroded dome. The most accurate order of the geological events in the area, from oldest to youngest, is ..........

1. A rising magma, then an anticline, then erosion
2. B rising magma, then erosion, then a syncline
3. C a syncline, then rising magma, then erosion
4. D an anticline, then rising magma, then erosion

The upward folding of rocks may result from ..........

1. A a normal dome
2. B an inverted dome
3. C cross-cutting dykes
4. D parallel sills

Igneous rocks may form a fold under the effect of ..........

1. A a batholith
2. B sills
3. C a lopolith
4. D lava flows

A laccolith causes the formation of ..........

1. A a fault with horizontal movement
2. B a fold with its oldest layers at the centre
3. C a fault in which the layers are repeated vertically
4. D a fold with its youngest layers at the centre

The geological structure in the opposite figure results from an igneous intrusion that may come from the rise of ..........

1. A low-viscosity lava
2. B high-viscosity lava
3. C high-viscosity magma
4. D low-viscosity magma

The igneous structure that extends for about 200 km below the Earth's surface is called ..........

1. A a laccolith
2. B a lopolith
3. C lava flows
4. D a batholith

What is the type of igneous intrusion in the following vertical section?

1. A Dyke
2. B Sill
3. C Laccolith
4. D Lopolith

Parallel sills are products of ..........

1. A the solidification of lava flows
2. B the intrusion of melt
3. C the cooling of lava
4. D the breaking of volcanic necks

Magma (A) has a high viscosity and magma (B) has a low viscosity. Their shapes after solidification and their effects on the surrounding rocks respectively are ..........

1. A (A) a normal dome with a syncline / (B) an inverted dome with an anticline
2. B (A) an inverted dome with a syncline / (B) a normal dome with an anticline
3. C (A) a normal dome with an anticline / (B) an inverted dome with a syncline
4. D (A) an inverted dome with an anticline / (B) a normal dome with a syncline

Pyroxene and mica may occur together in all of the following except ..........

1. A microgranite sills
2. B andesite ropes
3. C microdiorite dykes
4. D a diorite batholith

What does the igneous form (A) intruding into rock (B) in the opposite rock section represent?

1. A A sill
2. B A dyke
3. C Volcanic ejecta
4. D Volcanic breccia

The opposite graph represents four different areas (A), (B), (C) and (D) in which magma rises. The areas likely to have anticlines are ..........

1. A A, B
2. B C, D
3. C B, C
4. D A, C

Here is a vertical section. Study it well, then answer:
Rock (E) is made mainly of the mineral ..........

1. A quartz
2. B gypsum
3. C calcite
4. D olivine

Here is a vertical section. Study it well, then answer:
Structure (H) represents ..........

1. A a joint
2. B a dyke
3. C a sill
4. D a batholith

The following vertical section represents an eroded dome-shaped rock structure in a mountainous area. Study it well, then answer:
The letter (A) in the previous section represents ..........

1. A a fold axis
2. B a fold limb
3. C hanging wall rocks
4. D footwall rocks

The following vertical section represents an eroded dome-shaped rock structure in a mountainous area. Study it well, then answer:
The melt that formed this igneous intrusion is ..........

1. A of high viscosity
2. B of low viscosity
3. C parallel to the layers
4. D cutting across the layers

A rock sample was taken from a laccolith and heated until it melted completely, then the melt was left to cool and crystallized at a temperature of about 900 - 1000 °C. The rock formed by the crystallization is expected to be ..........

1. A basalt
2. B dolerite
3. C microgranite
4. D andesite

Molten lava flows over long distances in the form of ..........

1. A volcanic fragmental material
2. B volcanic ropes
3. C volcanic breccia
4. D volcanic ash

The opposite figure represents an active volcano in an area. The likely rock texture in (1) and (2) respectively is ..........

1. A (1) fine-grained / (2) porphyritic
2. B (1) non-crystalline / (2) coarse
3. C (1) coarse / (2) porphyritic
4. D (1) porphyritic / (2) glassy

What is the opposite volcanic feature formed by viscous lava erupting from the crater of a volcano?

1. A Igneous domes
2. B Igneous dyke
3. C Pillow lava
4. D Volcanic breccia

The following model shows a volcanic cone in which different igneous forms appear. Study it well, then answer:
Which of the following choices expresses the igneous forms in (G) and (F) respectively?

1. A (F) volcanic breccia / (G) lava flows
2. B (F) volcanic ash / (G) volcanic breccia
3. C (F) lava flows / (G) volcanic breccia
4. D (F) volcanic breccia / (G) volcanic ash

The following model shows a volcanic cone in which different igneous forms appear. Study it well, then answer:
What are the igneous forms (1) and (2) shown in the model?

1. A (1) sill, (2) dyke
2. B (1) laccolith, (2) sill
3. C (1) dyke, (2) sill
4. D (1) laccolith, (2) dyke

Which of the following forms is made of rocks with a coarse texture?

1. A Sills
2. B Pillow lava
3. C A batholith
4. D Volcanic ropes

The opposite figure represents one of the products of volcanoes, which is ..........

1. A volcanic ejecta
2. B volcanic ash
3. C volcanic breccia
4. D solidified lava

The texture of the rocks of volcanic ejecta may be ..........

1. A porphyritic
2. B fine
3. C coarse
4. D granular

The opposite sample is of an igneous rock. Study it well, then answer:
(1) What are the intrusive (hypabyssal) and plutonic equivalents of this rock?
(2) Why does the rock float when placed in water?

Study the opposite figure, then answer:
(1) Deduce the name of the rock.
(2) Classify the rock.
(3) What is the type of texture?

The opposite figure shows a sample of a plutonic igneous rock. Study it well, then answer:
(1) Name the rock and its type (in terms of chemical composition).
(2) Deduce the name of its volcanic equivalent, and state its texture.

The opposite figure shows a sample of an igneous rock whose crystals are visible to the naked eye and which contains about 72 % silica. Study it well, then answer:
(1) What type of rocks has this texture and colour?
(2) What is the mineral composition of the rock shown?
(3) Deduce four different examples of rocks similar to it in chemical composition.

Study the opposite graph, then answer:
(1) Deduce an example of samples (A), (C), (D) and (E).
(2) Compare sample (B) and sample (F) in terms of cooling rate.

You have three samples of different rocks:
The first sample: dark, with large crystals, and contains some amphibole.
The second sample: light-coloured, light in weight and rich in gas bubbles.
The third sample: light-coloured with clear crystals.
Name the three samples.

Study the following table, which shows the classification of igneous rocks, then answer:
(1) Which rocks are represented by the letters (D), (C) and (B)?
(2) Which rock in the table forms from the crystallization of lava at a temperature of about 900°?

The opposite figure shows the mineral composition of a type of igneous rock. Study it well, then answer:
(1) What type of rocks has this mineral composition?
(2) Deduce the name of a volcanic rock that belongs to this type of rock.
(3) What is the silica percentage in this type of rock?

Study the opposite vertical section, then answer:
(1) Explain the difference in texture between rocks (D) and (B).
(2) Which is older, rock (A) or rock (C)?

The opposite model shows the forms of igneous rocks in nature. Study it well, then answer the following:
(1) Identify structures (2) and (3).
(2) What tectonic structure forms under the effect of structure (1) and structure (5)?

During your visit to a quarry exhibition, you found a statue made of a rock in which the colours of its minerals appear: olivine, pyroxene and amphibole. What is the name of this rock? (Trial exam / May 2021)

1. A Basalt
2. B Diorite
3. C Gabbro
4. D Peridotite

Which of the following graphs expresses the relation between the number of crystals in an igneous rock and the depth at which this rock crystallizes? (Trial exam / May 2021)

1. A A
2. B B
3. C C
4. D D

What is the correct ascending order of the hypabyssal igneous rocks in terms of silica percentage? (Trial exam / June 2021, Sample exam 2025)

1. A Dolerite → diorite → microgranite
2. B Peridotite → microgranite → diorite
3. C Peridotite → diorite → gabbro
4. D Basalt → andesite → rhyolite

The sample in the opposite figure represents the rock .......... (1st session 2021)

1. A rhyolite
2. B basalt
3. C gabbro
4. D diorite

On a visit to the geological museum, you found a sample of a light-coloured igneous rock with large clear crystals. Which of the following minerals are expected not to be in this rock sample? (1st session 2021)

1. A Olivine and pyroxene
2. B Quartz and amphibole
3. C Quartz and muscovite
4. D Orthoclase and biotite

A rock sample with microscopic crystals contains large percentages of olivine and pyroxene. The rock is expected to be .......... (2nd session 2021)

1. A ultrabasic plutonic
2. B basic plutonic
3. C intermediate volcanic
4. D ultrabasic volcanic

Which of the following factors affects the difference in the mineral composition of igneous rocks? (2nd session 2021)

1. A The place of crystallization
2. B The texture of the rock
3. C The crystallization temperature
4. D The cooling rate of the melt

You have a dark-coloured igneous rock. This indicates .......... (2nd session 2021)

1. A its silica percentage and its chemical composition
2. B its texture and the conditions of its formation
3. C the place of crystallization and the size of its crystals
4. D its cooling rate

What are the type and texture of the rock forming the sample in the opposite picture? (1st session 2022)

1. A Acidic - porphyritic
2. B Intermediate - coarse
3. C Intermediate - porphyritic
4. D Acidic - coarse

What is the type of rock that is rich in sodium and calcium and has crystals of different sizes? (1st session 2022)

1. A Acidic intrusive
2. B Intermediate intrusive
3. C Intermediate plutonic
4. D Acidic plutonic

What is the type of rock that has a dark colour and clear crystals? (2nd session 2022)

1. A Ultrabasic extrusive
2. B Acidic plutonic
3. C Intermediate extrusive
4. D Basic plutonic

By studying the picture of the rock sample in front of you, what is the type of rock forming this sample? (2nd session 2022)

1. A Acidic, coarse, crystallization temperature 750 °C
2. B Acidic, fine, crystallization temperature 750 °C
3. C Intermediate, coarse, crystallization temperature 1100 °C
4. D Intermediate, fine, crystallization temperature 900 °C

A rock, a quarter of whose content is a mineral with a conchoidal fracture, formed from the solidification of lava accompanied by escaping gases. What are the type and name of the rock? (Trial exam 2023)

1. A Basic - basalt
2. B Intermediate - andesite
3. C Acidic - pumice
4. D Ultrabasic - komatiite

You have two samples of granite and gabbro of equal volume. These two samples differ in all of the following except .......... (1st session 2023)

1. A the iron percentage
2. B the colour of the crystals
3. C the crystallization temperature
4. D the texture of the rock

Arrange the following rocks in ascending order according to the number of crystallization centres in samples of equal volume: (1st session 2023)
(1) Obsidian. (2) Rhyolite. (3) Dolerite. (4) Peridotite.

1. A (2), (4), (3), (1)
2. B (1), (3), (4), (2)
3. C (1), (4), (3), (2)
4. D (3), (1), (4), (2)

What is the type of rock that contains minerals that crystallized quickly in the last stages of the cooling of the melt? (2nd session 2023)

1. A Basic volcanic
2. B Acidic volcanic
3. C Acidic plutonic
4. D Basic plutonic

From the opposite graph, what are the names of rocks (Y) and (X)? (2nd session 2023)

1. A (X) gabbro, (Y) andesite
2. B (X) basalt, (Y) diorite
3. C (X) komatiite, (Y) granite
4. D (X) basalt, (Y) granite

On a trip to the geological museum, you found the rock samples marked by the numbers (1), (2) and (3). What are the texture and place of formation of the three samples respectively? (2nd session 2023)

1. A (vesicular, extrusive) / (porphyritic, intrusive) / (coarse, plutonic)
2. B (vesicular, extrusive) / (coarse, plutonic) / (porphyritic, intrusive)
3. C (coarse, plutonic) / (vesicular, extrusive) / (porphyritic, intrusive)
4. D (porphyritic, intrusive) / (vesicular, extrusive) / (coarse, plutonic)

The figures in front of you represent samples of rocks that crystallized from the cooling of a melt:
What is the texture of rock (1)? And what is the type of rock (2)? (2nd session 2024)

1. A Fine - basic
2. B Coarse - ultrabasic
3. C Fine - acidic
4. D Coarse - intermediate

If you know that calcium is part of some feldspars, which of the following rocks has a glassy texture and is rich in calcium? (2nd session 2024)

1. A Acidic volcanic
2. B Acidic plutonic
3. C Intermediate plutonic
4. D Basic volcanic

When the ions of the elements of the melt react and calcium plagioclase changes into sodium plagioclase, this is accompanied by .......... (Sample exam 2025)

1. A a decrease in temperature
2. B an increase in temperature
3. C an increase then a decrease in temperature
4. D a constant temperature

The opposite graph shows the percentages of the components of four groups of igneous rocks (A), (B), (C) and (D), given that: (Sample exam 2025)
(A): ultrabasic rocks, (B): basic rocks, (C): intermediate rocks, (D): acidic rocks.
What do (X), (Y), (Z) and (L) represent respectively?

1. A (X) silica / (Y) iron / (Z) potassium / (L) sodium
2. B (X) silica / (Y) calcium / (Z) potassium / (L) iron
3. C (X) iron / (Y) silica / (Z) potassium / (L) calcium
4. D (X) iron / (Y) sodium / (Z) calcium / (L) potassium

What is the ascending order of the following rocks (pumice - microdiorite - komatiite) according to melting temperature? (Sample exam 2025)

1. A Pumice, then komatiite, then microdiorite
2. B Komatiite, then pumice, then microdiorite
3. C Pumice, then microdiorite, then komatiite
4. D Komatiite, then microdiorite, then pumice

From the opposite chart, which rocks are represented by the letters (X) and (Z) respectively? (Sample exam 2025)

1. A (X) peridotite / (Z) obsidian
2. B (X) dolerite / (Z) diorite
3. C (X) andesite / (Z) komatiite
4. D (X) pumice / (Z) andesite

Which igneous rock forms from the cooling of lava and contains olivine and amphibole? (1st session 2025)

1. A Andesite
2. B Basalt
3. C Rhyolite
4. D Gabbro

From the graph in front of you, which of the following rocks are represented by the letters (B), (C) and (D) respectively? (Sample exam 2026)

1. A (B) basalt - (C) microgranite - (D) komatiite
2. B (B) microgranite - (C) basalt - (D) obsidian
3. C (B) basalt - (C) komatiite - (D) granite
4. D (B) microdiorite - (C) peridotite - (D) obsidian

You have two samples of igneous rocks, each with crystals of different sizes.
The first sample: contains crystals of olivine, pyroxene and calcium feldspar.
The second sample: contains crystals of pyroxene, quartz, feldspar and mica.
From the above, we can deduce that the two samples respectively are of the rocks .......... (Sample exam 2026)

1. A dolerite and microdiorite
2. B gabbro and microdiorite
3. C dolerite and diorite
4. D basalt and andesite

Which of the following factors does not play a role in determining the shapes of hypabyssal igneous domes? (1st session 2021)

1. A The viscosity of the magma
2. B The mineral composition of the magma
3. C The crystallization rate of the magma
4. D The density of the magma

Which of the following statements is correct about the section in front of you? (2nd session 2021)

1. A The igneous intrusion (A) is younger than the fault (B)
2. B The section has an angular unconformity surface
3. C The fault (B) is younger than the igneous intrusion (A)
4. D The area was affected by tensional forces

A sedimentary sequence of 3 layers was intruded by high-viscosity magma. What are the characteristics of the tectonic structure formed? (1st session 2023, Sample exam 2025)

1. A Its two limbs come closer together at the top
2. B Its two limbs move apart at the top
3. C The hanging wall rocks move up
4. D The hanging wall rocks move down

What form results from the accumulation of low-viscosity magma between rock layers? (1st session 2023)

1. A A fold
2. B A lopolith
3. C A laccolith
4. D A sill

From studying the opposite vertical section, we conclude the presence of .......... (2nd session 2024)

1. A (X) a dolerite lopolith, (Y) a reverse fault
2. B (X) a dolerite laccolith, (Y) a strike-slip fault
3. C (X) a microgranite lopolith, (Y) a reverse fault
4. D (X) a microgranite laccolith, (Y) a thrust fault

A sedimentary sequence of two layers; the lower layer contains a coral reef fossil that was affected by an igneous intrusion whose upper surface is arched upward. What are the characteristics of the fossil in the lower layer? And what tectonic structure is formed? (2nd session 2024)

1. A Intact - anticline
2. B Deformed - anticline
3. C Intact - syncline
4. D Deformed - syncline

One of the forms of hypabyssal igneous rocks is .......... (1st session 2025)

1. A laccoliths and batholiths
2. B volcanic ejecta and lopoliths
3. C laccoliths and volcanic breccia
4. D ropes and lopoliths

In the vertical section shown in front of you, what do the igneous forms (X) and (Y), formed from the crystallization of a melt with about 60 % silica, represent? (1st session 2025)

1. A (X) a sill / (Y) a microdiorite dyke
2. B (X) a sill / (Y) a dolerite dyke
3. C (X) a dyke / (Y) a microgranite dyke
4. D (X) a dyke / (Y) a microdiorite sill

Folds may form together with some igneous intrusions. Which of the following is a cause and a result of fold formation? (2nd session 2025)

1. A Sill - a fold with its youngest layers at the centre
2. B Lopolith - a fold with its oldest layers at the centre
3. C Laccolith - a fold with its oldest layers at the centre
4. D Dykes - a fold with its oldest layers at the centre

Which of the following igneous forms took the longest time to cool? (2nd session 2025)

1. A A diorite batholith
2. B Basalt ropes
3. C Andesite pillows
4. D Rhyolite ropes

An igneous rock that extends for about 250 km, formed from a sodium-rich melt that lost its heat slowly, takes the form of .......... (Sample exam 2026)

1. A a microgranite batholith
2. B a granite batholith
3. C a granite sill
4. D a microgranite sill

Sedimentary layers were affected by high-viscosity magma that crystallized in a dome shape beneath them, then were subjected to compression that caused breaking and movement of one side over the other. We expect to find .......... (Sample exam 2026)

1. A a syncline and a thrust fault
2. B an anticline and a normal fault
3. C a syncline and a reverse fault
4. D an anticline and a thrust fault

Deep plutonic igneous masses such as batholiths form when .......... (Sample exam 2026)

1. A magma is pushed between existing rock layers
2. B magma crystallizes at a very great depth inside the Earth's crust
3. C magma erupts and solidifies on the Earth's surface
4. D magma is pushed into vertical cracks cutting across the layers

In which of the following forms can obsidian be found? (Trial exam / June 2021, Sample exam 2025)

1. A Laccolith
2. B Dykes
3. C Pillows
4. D Lopolith

What is the difference between dolerite dykes and basalt ropes? (1st session 2022)

1. A The silica percentage
2. B The mineral composition
3. C The crystallization temperature
4. D The texture of the rock

A rock sample was taken from the highest point of an island in the Atlantic Ocean. What is the correct rock classification of this sample? (2nd session 2022)

1. A Acidic plutonic igneous rocks
2. B Basic volcanic igneous rocks
3. C Intermediate plutonic igneous rocks
4. D Acidic volcanic igneous rocks

What is the result of the repeated eruptions of Mount Etna? (2nd session 2022)

1. A The formation of fine-grained igneous rocks
2. B The intrusion of igneous dykes and sills
3. C The formation of igneous rocks with clear crystals
4. D The intrusion of inverted igneous domes

Ropes and pillows rich in potassium are made of the rock .......... (Trial exam 2023)

1. A andesite
2. B dolerite
3. C granite
4. D rhyolite

What does the intrusion of magma along the boundary surface between limestone and the sandstone above it indicate? (1st session 2023)

1. A An angular unconformity
2. B A nonconformity
3. C There is no unconformity
4. D A disconformity

What rock forms from the solidification of a low-silica melt in the form of pillows? (2nd session 2023)

1. A Dolerite
2. B Andesite
3. C Gabbro
4. D Basalt

What type of rocks appears in the form of pillows and is dark black in colour? (1st session 2024)

1. A Acidic intrusive
2. B Ultrabasic extrusive
3. C Intermediate extrusive
4. D Basic intrusive

Which of the following forms of igneous rocks forms directly on the Earth's surface from the solidification of lava? (Sample exam 2026)

1. A Batholiths and lopoliths
2. B Dykes and laccoliths
3. C Pillows and igneous ropes
4. D Domes and sills

The following figure represents a vertical section of sedimentary layers containing igneous intrusions. Study it well, then answer: (2nd session 2024)
(1) What is the type of unconformity surface (X - X)? And why?
(2) Is (Y - Y) an unconformity surface?
(3) What is the shape of the igneous intrusion (M)?