Definition of isoclinal in US English:



  • Denoting a fold of strata so acute that the two limbs are parallel.

    • ‘These isoclinal folds deform ‘early’ domains which record a pre-Main Central Thrust compositional banding.’
    • ‘Large tight or isoclinal folds with limbs several tens of metres long occur locally.’
    • ‘Even the youngest Triassic rocks are strongly folded, in places by isoclinal, recumbent folds.’
    • ‘However, quarry outcrops of mainly white halitic mylonites display isoclinal folds that suggest a more impressive past.’
    • ‘Asymmetrical folds and axial planar quartz veins, isoclinal and rootless folds and boudinage of chert layers are common.’


Mid 19th century (denoting ‘equal magnetic inclination’): from iso- ‘equal’ + Greek klinein ‘to lean, slope’ + -al.