Exposed Units: Malverns Complex
Conservation Status: Local Geological Site; SSSI; Within an AONB
Dingle Quarry is split into three different levels: Lower, Middle and Upper Dingle. Lower Dingle is located to the rear of a bus stop, with much of the exposure obscured by vegetation. Middle and Upper Dingle are located off a path directly above the bus stop. Middle Dingle can be easily accessed, whereas Upper Dingle can not be accessed safely.
Middle and Upper Dingle:
Diorite is the predominant rock type in Dingle Quarry, which is intruded by granites and a large dolerite dyke.
The dolerite dyke is 4m thick and forms a step in the quarry floor which separates Middle Dingle from Upper Dingle. The dyke is orientated NW/SE. The precise age of the dyke is unknown, but it is one of the youngest features within the quarry as it intersects the diorite mass, as well as the smaller granitic veins and intrusions. The lack of foliation in the dolerite indicates that it was intruded after the period of compression that gives the granites and diorite mass their foliated fabric. A chilled margin can be viewed in places where the dolerite was intruded into cold country rocks (i.e. the granites and diorite had already cooled down).
As well as the dolerite dyke there are some small granitic intrusions in the diorite, which are truncated by the dyke. Granite is also present in the north-east corner of the quarry. The granites and diorites in the quarry are foliated, which formed during compressional deformation that took place during the Precambrian era of geological time.
Dingle Quarry provides geologists with the opportunity to view the order of events that occurred to create this part of the Malvern Hills:
Normal faulting occurs between the dolerite dyke and underlying diorites.
This site is part of the Community Earth Heritage Champions Project.
Dyke – A sheet like, near vertical minor intrusion.
Chilled margin – The fine grained, outer layer of an igneous body formed by rapid cooling
General view of Lower Dingle
Middle and Upper Dingle quarry. Dolerite dyke seen as step separating the two levels as a step.
Sharp contact between the dolerite dyke (bottom) and Malverns Complex granite (top).
General view of Lower Dingle
Diagram illustrating the relationships between different rock types at Dingle Quarry.
Diagram illustrating calcite mineralisation at the boundary between the dolerite dyke and Malverns Complex granite.
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