Hornblende gabbro is one of the park's more specialized geology topics. Learn where it appears and why it matters to the valley's rock record.
Not every famous park rock is visually dramatic; some are memorable because crews kept writing about them.
What It Is |
Hornblende gabbro is a coarse-grained intrusive rock with dark minerals and a heavier, blockier look than many nearby exposed units. |
Where It Shows Up |
Small mapped exposures and weathered blocks appear in parts of the northern geology belt and along disturbed cuts where deeper material is visible. |
Why It Gets Mentioned |
The rock's appearance, durability, and trace magnetic behavior have made it memorable in both geology notes and a few older field anecdotes. |