The document discusses the Bowen reaction series, which describes the order in which minerals crystallize from cooling magma. It outlines Norman Bowen's experimental work in the early 1900s that determined the general progression of mineral formation. The Bowen reaction series is diagrammed as a "Y" shape, with higher temperature minerals like olivine forming at the top and lower temperature minerals like quartz at the bottom. It distinguishes between the continuous and discontinuous reaction series, and how fractional crystallization changes the composition of the remaining magma over time. The principles are used to understand the relationship between mineral assemblages, rock types, and the temperatures at which different magmas cool.

1. DEPARTMENT OF APPLIED GEOLOGY
DR. HARISINGHGOUR VISHWAVIDYALAYA, SAGAR(M.P.)
PRESENTATION
ON
“BOWEN REACTIONSERIES
AND REACTIONPRINCIPLES”

2. PRESENTED BY:
1- YASHKUMARRAJAK.
2- MOHITKUMAR.
3- DIPENDRA KUMAR NAMDEV.
4- ANKITPANDEY.
5- RAJEEVDEWANGAN.
6- ABHISHEK TRIPATHI.
7- ANKITPANDIT.
UNDER GUIDANCE OF:
DR. HAREL THOMAS
PROFESSOR,DEPARTMENT OF APPLIED GEOLOGY

3. INDEX…..
•INTRODUCTION.
•WHAT IS BOWEN REACTION SERIES ?
•DIAGRAM
•CONTINUOUS REACTION SERIES.
•DISCONTINUOUS REACTION SERIES.
•FRACTIONATION.
•TYPES OF MAGMA.
•BOWEN REACTION PRINCIPLE.

4. INTRODUCTION…..
• BACK IN THE EARLY 1900’s, N.L.BOWEN AND OTHER AT THE GEOPHYSICAL
LABORATORIES IN WASHINGTON D.C. BEGAN EXPERIMENTAL STUDIES INTO THE
ORDER OF CRYSTALLIZATION OF THE COMMON SILICATE MINERALS FROM A
MAGMA.
• THE IDEALIZED PROGRESSION WHICH THEY DETERMINED IS STILL ACCEPTED AS
THE GENERAL MODEL FOR THE EVOLUTION OF MAGMA DURING THE COOLING
PROCESSES.
• IT DESCRIBES THE FORMATION OF IGNEOUS ROCKS FROM DIFFERENT STARTING
TEMPERATURES AND MAGMA COMPOSITIONS.

5. WHAT IS BOWEN REACTION SERIES ?
• IT IS THE WORK OF PETROLOGIST, NORMAN BOWEN WHO WAS ABLE TO EXPLAIN
WHY CERTAIN TYPES OF MINERALS TEND TO FOUND TOGETHER WHILE OTHER
ARE ALMOST NEVERASSOCIATED WITH ONE ANOTHER.
• THE BOWEN REACTION SERIES IS HAVING TWO BRANCHES-THE CONTINUOUS
AND DISCONTINUOUS SERIES. THE BRANCH ON THE RIGHT IS THE CONTINUOUS.
THE MINERALS AT THE TOP OF THE ILLUSTRATION ARE FIRST TO CRYSTALIZE
AND SO THE TEMPERATURE GRADIENT CAN BE READ TO BE FROM HIGH TO LOW
WITH THE HIGH TEMPERATURE MINERALS BEEN ON THE TOP AND THE LOW
TEMPERATURE ONES ON THE BOTTOM.

6. DIAGRAM….

7. IT IS DIAGRAMEDAS “Y”.
• THE FIRST HORIZONTAL LINE –
USUALLY PLACED JUST ABOVE THE
TOP OF THE “Y” – REPRESENTS A
TEMPERATURE OF 1800°C.
• THE NEXT HORIZONTAL LINE REPRESENTS A TEMPERATURE OF 1100°C AND IS
LOCATED ONE-THIRD OF THE WAY BETWEEN THE TOP OF THE “Y” AND THE
POINT WHERE THE TWO ARMS JOIN THE BASE.
• A THIRD LINE REPRESENTING A TEMPERATURE OF 1900°C IS LOCATED TWO-
THIRDS OF THE WAY FROM THE TOP OF THE “Y” TO THE JUNCTION OF THE
UPPER ARMS.

8. • A FOURTH HORIZONTAL LINE REPRESNTING A TEMPERATURE OF 600°C
INTERSECTS THE TRIPLE POINT JUNCTION WHERE THE UPPER ARMS OF THE”Y”
MEET THE BASE PORTION.
• THE HORIZONTAL TEMPERATURE LINES DIVIDE THE “Y”INTO FOUR
COMPOSITIONAL SECTIONS.
• MINERAL FORMATION IS NOT POSSIBLE ABOVE 1800C.
• BETWEEN 1100°C AND 1800°C, ROCKS ARE ULTRAMAFIC IN COMPOSITION.
• BETWEEN 900°C AND 1100°C, ROCKS ARE MAFIC IN COMPOSITION.
• BETWEEN 600°C AND 900°C, ROCKS ARE INTERMEDIATE IN COMPOSITION.
• BELOW 600°C, FELSIC ROCKS FORM.

9. CONTINUOUS REACTIONSERIES……
• IT STARTS FROM THE RIGHT.
• EARLIER FORMED MINERALS SLOWLY AND STEADILY CHANGE INTO NEW MINERALS.
• THE HIGHEST TEMPERATURE PLAGIOCLASE HAS ONLY CALCIUM {Ca}.
• THE LOWEST TEMPERATURE PLAGIOCLASE HAS ONLY SODIUM {Na}.
• CRYSTALLIZATION OF PLAGIOCLASE FELDSPAR DEPLETES CALCIUM FROM THE PARENT
MAGMA AND REPLACES THE MISSING ELEMENT WITH SODIUM AS NEW MINERALS ARE
FORMED.
• FELDSPAR MINERALS FORM CONTINUALLY AT THE SAME TIME AS MINERALS SHOWN OPPOSITE
IN THE DISCONTINUOUS SERIES.

11. DISCONTINUOUS REACTIONSERIES…..
• IT STARTS FROM THE LEFT.
• EARLIER FORMED CRYSTALS REACT WITH THE REMAINING MAGMA IN A SERIES OF STEPS TO
FORM A NEW MINERAL.

12. • THESE ARE GROUP OF MAFIC OR IRON MAGNESIUM BEARING MINERALS LIKE OLIVINE,
AMPHIBOLES, AND BIOTITE.
• FROM AN INITIAL BASALTIC MAGMA, THE FIRST FORMED MINERAL IS OLIVINE[Mg₂SiO₄].
• REMOVAL OF OLIVINE INCREASES THE SILICA CONTENT AND DECREASES THE IRON AND
MAGNESIUM IN THE PARENT MAGMA.
• AS THE TEMPERATURES LOWERS, A NEW CHAIN SILICATE MINERAL, PYROXENE[Ca
Mg(SiO3)₂]IS FORMED.

13. • AS THE TEMPERATURE DROP FURTHER FROM 1100°C-850°C, THE MAGMA BECOMES EVEN
RICHER IN SILICATES.
• AMPHIBOLE BEGINS TO FORM.
• THE ORIGINAL BASALTIC MAGMA BECOMES ANDESITIC MAGMA.

14. • As temperature cools to 800°c and silica increases further, the sheet silicate biotite forms.
• Andesitic magma now evolves into rhyolitic magma.
rhyolite

15. • Quartz forms last at low temperature.
• Muscovite mica and potassium feldspar also form at this temperature.
• All of these minerals are poor in mafic components which were removed from the melt by minerals that
formed earlier.
quartz muscovite potassium feldspar
This Photo by Unknown Author is licensed
under CC BY-SA

16. Fractionation….
• it is the process by which minerals are formed and removed from the molten rock.
• As the magma cools, higher temperature, mafic minerals crystallizes, and more felsic magma is left.
Systematic crystal fractionation.

17. Types of magma…..
• Igneous rock come in four basic varieties: ultramafic, mafic, intermediate, and felsic.
• Bowen reaction series shows the relationship among the 8 rock forming minerals.
• Minerals from the bottom of Bowen reaction series tend to be more sodium and potassium rich, high in
silica, cooler in temperature and light colour.
• Bowen’s reaction series describes the temperature depicts mineral formation in a cooling magma.
• The continuous side depicts a solid solution series.
• The discontinuous side depicts mineral formation at decreasing temperatures.
• Viscosity increases as the temperature cools.

18. • The temperature of the magma and the rate of cooling determines which minerals are stable.
• Slower the magma cools, larger the crystal size.
• Bowen reaction series allows the geologists to predict chemical composition and texture based upon the
temperature of the magma cooling.

19. Bowen reaction principle……
• A concept, first propounded in 1928 by norman bowen, which explains how minerals can respond to the
changing equilibrium conditions when a magma is cooled, either by a continuous, diffusion-controlled
exchange of elements with the magma or discontinuous melting of minerals.
• IN A CONTINUOUS EXCHANGE, SOLIDS SOLUTION MINERALS SUCH AS FELDSPAR ADJUST THEIR
COMPOSITION DURING COOLING BY A CONTINUOUS DIFFUSION OF ELEMENTS BETWEEN
MAGMA.
• IN ADICONTINUOUS REACTION, MINERALS SUCH AS OLIVINEUNDERGO MELTING AT A SPECIFIC
TEMPERATURE DURING COOLING AT THE SAME TIME AS A NEW MINERAL IN EQUILIBRIUM
WITH THE MAGMA BEGINS TO CRYSTALLIZE.

20. HOPE YOU ENJOYED IT……