The Szekou Formation is a light bluish gray siltstone, with shale and fine grained sandstone. The Maanshan Formation is very similar. It is overlain by Hengchun Limestone and may interfinger.
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U.S. Geological Survey. Accessed July 23, 2010. Additionally, pebbles and cobbles of quartz are embedded within layers of sandstone and siltstone that interfinger with the Feltville Formation near Oakland, New Jersey.
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Collinear transfer zones include areas which the major fault boundaries are in line with one another. In many cases this geometry relies on the faults to splay at their terminations and interfinger with one another.
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Its uppermost beds interfinger with the Cochiti Formation.Smith et al. 1969, p.8 The tuffaceous facies of the Bearhead Rhyolite, extensively exposed at Kasha- Katuwe Tent Rocks National Monument, are assigned to the Peralta Tuff Member, a name first used by Kirk Bryan and J. E. Upson.
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The shales interfinger with sandstones and in certain parts coal beds are found. In the eastern domain around the Doros crater, dark iron-oxide cements occur in the upper conglomerate horizons.Wanke, 2000, p.21 In virtually all lithological units, bones of the amphibious reptile Mesosaurus tenuidens can be encountered in concretions.
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The Dundas group are Cambrian sedimentary beds that interfinger with the Mount Read Volcanics. They lie unconformably on the Precambrian basement. The kind of rock is sandstone, laminated mudstone and a pebble conglomerate in which the pebbles consist of quartzite, sandstone and green mudstone. The group was formed as a submarine fan.
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The Southesk Formation is discontinuously present in the Canadian Rockies from Jasper National Park to the Flathead area of southeastern British Columbia. It is also present in the subsurface beneath the adjacent plains to the east. It conformably overlies the Cairn Formation or, in the Crows Nest Pass area, the Borsato Formation. At its margins it may interfinger with the Perdrix and Mount Hawk Formations.
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Amphibolites interlayed with peridotite have been dated to 170 to 160 million years ago. Ultramafic massifs in the Ophiolite Zone are unconformably overlain by Late Jurassic and Late Cretaceous sandstones, marl, shale and limestone up to one kilometer thick. These sequences interfinger with Tithonian-Berriasian, Albian and Senonian limestones. Coarse-grained clastic rocks contain fragments of ophiolite, amphibolite, greywacke, shale, chert, limestone and pebbles of red granite.
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Between Asra and Khost, calcareous sediments interfinger with volcanic rocks. In east-central Afghanistan, 500 meters of sandstone, shale, marl and conglomerate overlies Paleozoic and Precambrian rocks. Conglomerate, greywacke and sandstone grading into limestone (rich in rudist fossils), sandstone and marl in the north and southeast suggests a large sedimentary basin. Limestone, marl and claystone up to 1.5 kilometers thick indicates a major marine transgression in the Aptian, from the north.
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The Boonton Formation is composed of reddish-brown to reddish-purple fine grained sandstone, as well as red, gray, purple, and black siltstone and mudstone. Siltstone and mudstone layers can be calcareous and feature dolomitic concretions. A well known fossil fish bed is known to exist in a carbonate rich siltstone near the top of the formation. Additionally, cross-bedded conglomerate layers interfinger with beds of the formation, usually bearing clasts of gneiss and granite.
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It contains volcanic tephra with an age of 6.8 to 7.1 Ma, identical to the Peralta Tuff Member of the Bearhead Rhyolite. The similarity in age with the Navajo Draw Member suggests the two members interfinger. The Picuda Peak Member is mostly reddish sandy conglomerate and arkosic sandstone. It contains beds formerly assigned to the Ceja Formation but which are now known to lie below the Rincones paleosurface, a major regional unconformity.
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The terrestrial stratigraphy of the Cenozoic is more difficult than that of marine deposits. The geologic timescale of the ICS is therefore based on marine fossils, that don't occur in terrestrial sediments. This makes the correlation of terrestrial deposits with the ICS timescale often difficult. Correlation is possible when marine deposits interfinger with terrestrial deposits (resulting from a series of transgressions and regressions of the sea during deposition), but this isn't the case everywhere.
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Mauritania is part of the Senegal Basin and its Mesozoic sedimentary sequence begins with Late Jurassic dolomite formed in a shallow marine environment. Offshore research has found Early Cretaceous detrital sediments lying atop Early Jurassic evaporites. The ocean receded in the region in the Maastrichtian near the end of the Cretaceous, followed by a large marine transgression in the early Cenozoic. The country's sedimentary rocks interfinger between continental sediments and silicate marine sediments in the west.
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The Strathmore Group is a Devonian lithostratigraphic group (a sequence of rock strata) in central Scotland. Its sandstones are interbedded with siltstones which interfinger with conglomerates. It is encountered from Arran in the west across the Midland Valley to Stonehaven in the east. The name is derived from Strathmore, Angus where this sequence occupies the axis of the Strathmore Syncline which runs for many tens of miles parallel to and south of the Highland Boundary Fault.
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The dominant lithology is sandstone, which is organised into a series of coarsening-upward cycles, laid down by a west-draining axial river system. At the basin margins the sandstones interfinger with conglomerates deposited by alluvial fans. The northern conglomerates were deposited by mainly debris flow fans, while those to the south are mainly streamflow in type. Near the northern margin there is a zone where siltstones and mudstones are developed, forming the finest-grained sediments in the basin.
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South and east of the Grand Canyon, the evaporites and contorted sandstones (sabkha deposits) of Toroweap Formation interfinger with and are replaced by cross- bedded sandstones of the Coconino Sandstone. As a result, the Kaibab Limestone directly overlies the Coconino Sandstone in the Mogollon Rim region. The Kaibab Limestone directly overlies the White Rim Sandstone in northeastern Arizona and southeastern Utah. The upper contact of the Kaibab Limestone (Harrisburg Member) with the overlying Moenkopi Formation is an erosional unconformity and disconformity.
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The shallow marine basin had already formed earlier (Triassic), even before Aconcagua arose as a volcano. However, volcanism has been present in this region for as long as this basin was around and volcanic deposits interfinger with marine deposits throughout the sequence. The colorful greenish, blueish and grey deposits that can be seen in the Horcones Valley and south of Puente Del Inca, are carbonates, limestones, turbidites and evaporates that filled this basin. The red colored rocks are intrusions, cinder deposits and conglomerates of volcanic origin.
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These two formations with their diverse fossils were historically thought to represent sequential time periods with different environments, but in 2009 the Canadian palaeontologist DavidA. Eberth and colleagues found that there was partial overlap across the transition between them. The two formations "interfinger" across a stratigraphic interval that is about 25 m (82 ft) thick, which suggests that the fluvial and aeolian environments coexisted when the area was sedimented. Photos of the interfingering contacts between the formations The environment of the Nemegt Formation has been compared to the Okavango Delta of present-day Botswana.
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The Dedham Granite, Westwood Granite, and older rocks are overlain by the calc-alkaline Brighton Volcanic rocks, which consist of the altered basalt and andesite flows, pyroclastic rocks, breccia, tuff, and intrusive rocks. The upper part of the Brighton Volcanic rocks sporadically interfinger and interbedded with the Brookline and Dorchester members throughout the basin in the southern portion of the basin. Overlying the Squantum Member, the Cambridge Argillite consists of up to 5 km (3 miles) of laminated, dark to olive grey, graded, turbiditic siltstone and sandstone beds. Graded beds, starved ripples, scour marks, load casts and micro-faults are numerous.
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The British Coastal Deposits Group is a Quaternary lithostratigraphic group (a sequence of rock strata or other definable geological units) present in coastal and estuarine areas around the margins of Great Britain. They are a mix of sands, gravels, silts, clays and peat and, north of a line between the Ribble and Tyne, include glacio-eustatically raised deposits. They lie unconformably on deposits of variously the Britannia Catchments Group (with which they also interfinger), Albion Glacigenic Group, Caledonia Glacigenic Group, Dunwich Group, Crag Group or earlier bedrock. Their upper boundary is the present day ground surface.
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The clasts of the southern parts are predominantly from the surrounding Bredasdorp mountains and Bokkeveld rocks. To the east, an isolated bed in the Soutrivier valley is composed almost entirely of disc- shaped shale and siltstone clasts (with occasional vein quartz rocks). Other outcrops occur in smaller, isolated basins south of Soetendalsvlei at Jubilee, where pale red and grey conglomerates, mudstones, sandstones and tuffaceous rocks support occasional silcrete caps, as well as at Haasvlakte. Laterally, the limits of the Enon conglomerate beds often interfinger or transition gradually into the softer sands and mudstones of the Kirkwood Formation.
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This basal succession passes upward in cross-bedded sandstone and minor siltstone and claystone with flaser or lenticular bedding that are interpreted as tidal flat and tidal channel deposits. Horizontal to low-angle cross-bedded, fine- grained sandstone with intercalated bivalve pavements indicates tidal currents that operated in small flood and ebb tidal deltas and along the coast. Stacked successions of trough cross-bedded, medium- to coarse-grained sandstone of the upper part of the Indotrigonia africana Member are interpreted as tidal channel and sand bar deposits. At some places in the surroundings of Tendaguru Hill, these sediments interfinger with oolitic limestone layers that represent high-energy ooid shoals.
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During the Devonian Period, this basin filled with terrestrial red beds that interfinger with marine limestone and dolomites. Before deposition was terminated by marine regression, Upper Devonian black bituminous shale accumulated in the south-east of the basin. The remaining history of the Hudson Bay basin is largely unknown as a major unconformity separates Upper Devonian strata from glacial deposits of the Pleistocene. Except for poorly known terrestrial Cretaceous fluvial sands and gravels that are preserved as the fills of a ring of sinkholes around the centre of this basin, strata representing this period of time are absent from the Hudson Bay basin and the surrounding Canadian Shield.
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The Roxbury Conglomerate comprises the lower part of the Boston Bay Group, which is a 5,000-meter-thick (3 miles) sequence of sedimentary rocks that fill the Neoproterozoic Boston Basin in eastern Massachusetts. The upper part of the Boston Bay Group consists of the Cambridge Argillite, which overlies the Roxbury Conglomerate. The Roxbury Conglomerate traditionally has been subdivided into three subdivisions; (1.) basal Brookline Member (conglomerate and sandstone), (2.) medial Dorchester Member (mostly sandstone with minor conglomerate) and (3.) upper Squantum Member (largely diamictite). However, these three subdivisions of the Roxbury Conglomerate complexly interfinger with each other and lack the simple layer- cake distribution that past studies have described.Emerson, B.K. (1917) Geology of Massachusetts and Rhode Island.
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The macrobands in turn are composed of characteristic alternating layers of chert and iron oxides, called mesobands, that are several millimeters to a few centimeters thick. Many of the chert mesobands contain microbands of iron oxides that are less than a millimeter thick, while the iron mesobands are relatively featureless. BIFs tend to be extremely hard, tough, and dense, making them highly resistant to erosion, and they show fine details of stratification over great distances, suggesting they were deposited in a very low-energy environment; that is, in relatively deep water, undisturbed by wave motion or currents. BIFs only rarely interfinger with other rock types, tending to form sharply bounded discrete units that never grade laterally into other rock types.
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