The ignimbrite was radiometrically dated at 13 million years. Parts of the Mascall are interfingered with the Columbia River Basalt Group.
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Soomaspis splendida was probably a marine bottom dweller. The Soom Shale is sometimes interfingered with the glacial tillite of the Pakhuis Formation, indicating that Soomaspis lived in the open sea, near the edge of an ice sheet.
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The Stockton is described as a bajada. The sediments were a result of the rifting of Pangea. The sediments came from the southeast from a largely granitic terrane and spread across an even plain. Interfingered with the Stockton, the Lockatong Formation are lake sediments, which grew during wetter climatic cycles during the Late Triassic.
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Nearer Riversdale, Witteberg sandstone clasts are also present. At Herbertsdale, a large section is exposed, often interfingered with the neighbouring Kirkwood Formation. The southern portion of the Enon is composed mainly of angular Bokkeveld shale clasts in a pale reddish-grey matrix. The rock just south of the Hartebeeskuil dam however, is composed more of partially silicified sandstone and quartzite clasts.
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A clastic wedge consisting of the North Horn, Colton, and Wasatch was deposited northwards. These sediments interfingered with organic-rich lacustrine clays and carbonate muds of the Green River and Flagstaff facies. Later, deposits originated from the Uinta Mountains from the north, forming a southward-thinning clastic wedge. A carbonate sediment consisting of an organic-rich oil shale was deposited from the middle Eocene into the Oligocene.
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Rock sample collected east of Khunale The intra- volcanic rocks comprise silicified mudstone interfingered with diatomites. The term ‘silicified’ points to the fact that the calcium atoms in the calcium carbonate molecules have been replaced by silicium taken from the environment (isomorphic substitution). These deposits contain fossils of molluscs and gastropods. Between the towns of Hagere Selam and Inda Maryam Qorar (Dogu’a Tembien), roadcuts show around 45 metres thick sedimentary deposits.
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It was deposited at a time when sea level was relatively low and the shoreline was east of the Kaiparowits Plateau. The John Henry Member records fluctuations in the sea level. It contains interfingered marine and terrestrial deposits. In the southwestern region of the plateau the John Henry Member preserves ancient river systems which were carrying sediment into the basin from the uplifting Mogollon highlands and Sevier fold – thrust belt.
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Lake Norman in Ramsey Creek Park in Cornelius Lake Norman is a man-made lake that stretches 33.6 miles long, 9 miles wide, and covers 520 miles in shore line length. Its average depth is 33.5 feet, but at some points it drops down to 110 feet. The lake is mainly constructed of interfingered igneous and metamorphic rock. Metamorphic rock means that the rock was changed by heat, pressure or chemical action while embedded below the earth's surface.
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The warm water Saraburi Group in the east has numerous fossils, while the Ratburi Group in the west does not. In peninsular Thailand, sandstone is predominant interfingered with Ratburi Group limestones. Along the western edge of the Khorat Plateau, a limestone dominated shelf sequence abuts turbidites and pyroclastic flow deposits. A magmatic arc around a west-dipping subduction zone produced intermediate and felsic volcanic rocks in the north around Lampang to the east of Chiang Mai.
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Except for the sedimentary rocks mentioned above, most of the Mesozoic-age rocks in preserved in Southern California display intermediate to high grades of metamorphism, typical of material that may have been buried to mid-crustal depths (probably in a range of 10 to 20 kilometers). Although the region was no doubt extensively covered with terrestrial and marine sedimentary deposits that interfingered volcanic deposits from the volcanic centers, most of this material was stripped away by erosion following regional uplift that continued into the following Cenozoic Era.
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Szwarc, Tyler S., Johnson, Cari L., Stright, Lisa E., McFarlane, Christopher M., In revision, Interactions between axial and transverse drainage systems in the Late Cretaceous Cordilleran foreland basin: Evidence from detrital zircons in the Straight Cliffs Formation, southern Utah, USA: GSA Bulletin. On the eastern side of the Kaiparowits Plateau the John Henry Member preserves interfingered marine and coastal deposits. Careful analysis of the stacking patterns within these beds suggests that the seaway was receding during the bottom third of the John Henry Member. Sea level was rising and flooding the land during the middle portion of John Henry Member deposition.
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Metamorphic rocks composed primarily of amphibole, plagioclase, with subordinate epidote, zoisite, chlorite, quartz, titanite, and accessory leucoxene, ilmenite and magnetite which have a protolith of an igneous rock are known as Orthoamphibolite. Para-amphibolite will generally have the same equilibrium mineral assemblage as orthoamphibolite, with more biotite, and may include more quartz, plagioclase, and depending on the protolith, more calcite/aragonite and wollastonite. Often the easiest way to determine the true nature of an amphibolite is to inspect its field relationships; especially whether it is interfingered with other metasedimentary rocks, especially greywacke and other poorly sorted sedimentary rocks. If the amphibolite appears to transgress apparent protolith bedding surfaces it is an ortho-amphibolite, as this suggests it was a dyke.
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