Unit 4 of the Zhuhai Formation, situated beneath the complex buildup, is composed of a mixed sedimentary sequence of tuffaceous sandstone and calcareous ... is characterized by bioclastic limestone ...

beginning a steep and steady descent through the upper rock layers — Kaibab Limestone, Toroweap Formation, and Coconino Sandstone. Switchbacks intensify as you drop through the Coconino, easing up as ...

The trail crosses Garden Creek, swings over to the west canyon wall, and contours along the shale slopes for three-quarters of a ... Salt Creek drainage and descends through the ledgy Tapeats ...

Two towering limestone walls, roughly 40 feet (12 m) high and 25 feet (7.6 m) apart, form the sides of this natural "slide." These robust layers, hardened by time and weather, encase a softer, shaly ...

The reservoir zone was 118 metres thick with alternating siltstone, limestone and some thin sandstone layers with generally poor reservoir quality. No reservoir was proven in the secondary exploration ...

“At the center of the anticline, the Stony Gap Sandstone is eroded away, exposing the Greenbrier Limestone. This is the bedrock of Abbs Valley.” An anticline, beneath the surface, typically resembles ...

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