User:Scotfot/sandbox
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| Age | Intrusion | Lithology | Mineralogy and texture | Notes | |
| Carboniferous | Dykes | Tholeiitic basalt and dolerite (DT) | microporphyritic, euhedral olivine and subordinate plagioclase phenocrysts fine-grained or subophitic groundmass | Cut Mell Fell Conglomerate; geochemically similar to Cockermouth Lavas | |
| Neck | Lapilli-tuff (LZ) | clasts of country rock and glassy basalt | |||
| Devonian | Dykes | Lamprophyre (spessartite) (L) | acicular brown hornblende, plagioclase and interstitial quartz; augite microphenocrysts | Example seen in Haweswater quarry [NY 4947 1526] | |
| Plagioclase-quartz- biotite-phyric microgranite (FG) | micropoikilitic feldspar and quartz groundmass; single example with K-feldspar phenocrysts | Most are partly cleaved; those within the aureole of the Shap Pluton are not hornfelsed | |||
| Shap Pluton | Orthoclase-perthite- megaphyric granite (G) | up to 30% K-feldspar megacrysts; sparse microdioritic enclaves and veins of aplitic microgranite | Contact exposed in Sherry Gill [NY 5384 1012] and Longfell Gill [NY 5613 1009] Radiometric age 397 ± 7 Ma (K-Ar, biotite) | ||
| Ordovician | Haweswater Intrusions | Plugs and dyke-like masses | Dolerite (D) and gabbro (E) (including hornblende-gabbro) | plagioclase, augite, edenitic amphibole; accessory ilmenite, apatite, biotite, tourmaline; leucrocratic to melanocratic, intergranular and subophitic; in part porphyritic and two-phase | Locally with igneous layering. Weaklycleaved. Geochemically very similar to mafic rocks in the Borrowdale Volcanic Group.No isotopic age determination |
| Plug | Microdiorite (HD) | plagioclase, clinopyroxene, orthopyroxene; accessory garnet | Distinct from others in suite | ||
| Marginal dyke-like zone | Intrusive breccia | fragments of dolerite, gabbro, andesite and felsite in altered feldspathic clastic matrix | Marginal zone of Wallow Crag plug and scattered dykes | ||
| Dykes | Andesite (A), basaltic andesite (AB) and basalt (B) | Typically plagioclase-phyric | Sporadic, probably related to Borrowdale Volcanic Group | ||
| Sills | Andesite (A) | In Esk Pike Formation only; with chilled margins | |||
| Mainly andesite (A); also basaltic andesite (AB) and dacite (RD) | Mostly emplaced into volcaniclastic sandstone formations; many with peperitic margins |
