Oxford Cambridge and RSA
A-Level OCR 2025 Geology Paper 3
Thursday 19 June 2025 – Morning
A Level Geology
H414/03 Practical skills in geology
Time allowed: 1 hour 30 minutes
INSTRUCTIONS
INFORMATION
ADVICE
{Oxford Cambridge and RSA(OCR) is a leading UK awarding body, providing a wide range of
qualifications to meet the needs of candidates of all ages and abilities. OCR qualifications
include AS/A Levels, Diplomas, GCSEs, Cambridge Nationals, Cambridge Technicals,
Functional Skills, Key Skills, Entry Level qualifications, NVQs and vocational qualifications in
areas such as IT, business, languages, teaching/training, administration and secretarial skills.
It is also responsible for developing new specifications to meet national requirements and the needs
of students and teachers. OCR is a not-for-profit organisation; any surplus made is
invested back into the establishment to help towards the development of qualifications and
support, which keep pace with the changing needs of today’s society.}
,
, 3
1
(a) Fig. 1.1 in the Insert shows a thin section photograph of a carbonate rock.
(i) Name this rock using the Dunham classification scheme.
..........................................................................................................................................................
...................................................................................................................................................................... [1]
(ii) Calculate the magnification of the thin section photograph.
Magnification =................................................................... [2]
(iii) Describe the environment in which the carbonate rock in Fig. 1.1 in the Insert was deposited.
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
...................................................................................................................................................................... [2]
(iv) Explain how the carbonate rock in Fig. 1.1 in the Insert was formed.
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
...................................................................................................................................................................... [2]
(b) Fig. 1.2 in the Insert shows a hand specimen of a metamorphic rock.
(i) Estimate the ratio of dark to light minerals in the metamorphic rock.
dark minerals: light minerals = 1:...................................................................[1]
(ii) Explain what the texture of the rock in Fig. 1.2 suggests about the type and grade of
metamorphism the rock has undergone.
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
...................................................................................................................................................................... [2]
© OCR 2025 Turn over
A-Level OCR 2025 Geology Paper 3
Thursday 19 June 2025 – Morning
A Level Geology
H414/03 Practical skills in geology
Time allowed: 1 hour 30 minutes
INSTRUCTIONS
INFORMATION
ADVICE
{Oxford Cambridge and RSA(OCR) is a leading UK awarding body, providing a wide range of
qualifications to meet the needs of candidates of all ages and abilities. OCR qualifications
include AS/A Levels, Diplomas, GCSEs, Cambridge Nationals, Cambridge Technicals,
Functional Skills, Key Skills, Entry Level qualifications, NVQs and vocational qualifications in
areas such as IT, business, languages, teaching/training, administration and secretarial skills.
It is also responsible for developing new specifications to meet national requirements and the needs
of students and teachers. OCR is a not-for-profit organisation; any surplus made is
invested back into the establishment to help towards the development of qualifications and
support, which keep pace with the changing needs of today’s society.}
,
, 3
1
(a) Fig. 1.1 in the Insert shows a thin section photograph of a carbonate rock.
(i) Name this rock using the Dunham classification scheme.
..........................................................................................................................................................
...................................................................................................................................................................... [1]
(ii) Calculate the magnification of the thin section photograph.
Magnification =................................................................... [2]
(iii) Describe the environment in which the carbonate rock in Fig. 1.1 in the Insert was deposited.
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
...................................................................................................................................................................... [2]
(iv) Explain how the carbonate rock in Fig. 1.1 in the Insert was formed.
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
...................................................................................................................................................................... [2]
(b) Fig. 1.2 in the Insert shows a hand specimen of a metamorphic rock.
(i) Estimate the ratio of dark to light minerals in the metamorphic rock.
dark minerals: light minerals = 1:...................................................................[1]
(ii) Explain what the texture of the rock in Fig. 1.2 suggests about the type and grade of
metamorphism the rock has undergone.
..........................................................................................................................................................
..........................................................................................................................................................
..........................................................................................................................................................
...................................................................................................................................................................... [2]
© OCR 2025 Turn over
