Geologic Map of the Boxley Quadrangle, Newton and Madison Counties, Arkansas

Abstract

Mf of a thin coal bed approximately 250 ft above the base of the middle Bloyd sandstone. In 5 3 thin beds of sandstone. Shale and siltstone are dark gray and fissile to thin, The study area preserves an approximately 1,600-ft-thick record of early and late 1545 5 1530 Mf This work was conducted in a cooperative project between the U.S. Geological Survey 4 the Boxley quadrangle, the Bloyd-Atoka contact is placed at a similar level within a shale Qty Mbv ripple bedded. Sandstone is tan, very fine to fine grained, thin bedded with Paleozoic deposition on what is now the southern margin of the North American continent. and the U.S. National Park Service. We thank D.L. Zachry for discussions about the 1940 5 Oe Qal Qc Ql QUATERNARY hhg interval beneath an approximately 100-ft-thick interval of sandstone that underlies a ripple marks. Limestone includes medium to thick beds of red-brown Provincial series for Pennsylvanian and Mississippian units are from McFarland (1988). Pennsylvanian stratigraphy. Helpful reviews were provided by Angela Chandler and Paul Carrara. Mbv Qto 5 1945 prominent topographic ledge. This sandstone sequence is typical of Atoka facies in being fine to very fine grained, thin to medium bedded with ripple laminations (fig. 3A) and being Mb conglomerate, with clasts of fossil fragments and subrounded sandstone and The Middle Ordovician Everton Formation is a heterogeneous sandstone and carbonate Mbv Unconformity siltstone. The Brentwood Limestone Member at the base of formation (not unit that Suhm (1974) interpreted to have been deposited in barrier island and tidal flat hhc 2 2 laterally extensive across the quadrangle. An alternative contact that was considered, about Mbs 1550 5 2 REFERENCES CITED 5 mapped) is a 5-to 20-ft-thick limestone interval varying from massive gray depositional environments. The Everton Formation is unconformably overlain by the Upper hhg hbu Of ha Atokan 50 ft lower, would shift the sandstone interval including fucoid trace fossils (fig. 3B) from the 5 micrite to reddish-gray, coarse bioclastic limestone. Unit is conformable with Ordovician Fernvale Limestone. 1500 Angelier, Jacque, 1990, Inversion of field data in fault tectonics to obtain the regional 5 1500 upper Bloyd to the Atoka Formation (ha). This option was not favored because this Mbs Of Mp hhg 2 underlying Hale Formation. Forms moderate to steep slopes and is poorly The Mississippian Boone Formation is widespread within the northern part of the 5 Unconformity stress-III, A new rapid direct inversion method by analytical means: Geophysical

The effect of lithology on valley width, terrace distribution, and bedload provenance in a tectonically stable catchment with flat‐lying stratigraphy

“…Upstream of the study reach within Boxley Valley, channel and valley width is largely controlled by landslides and debris flows sourced from the Upper Mississippian and Lower Pennsylvanian shale, siltstone, and sandstone (Hudson and Turner, ) that contribute great volumes of large‐sized sediment that impinge upon the channel and valley floor, similar to observations by May et al (). The channel meander pattern in Boxley Valley is largely controlled by these deposits and it is likely that landslides and debris flows intermittently dammed upstream reaches.…”

“…Joint spacing in the medium-to thick-bedded carbonates typical of the Boone and Everton Formations ranges from 10 cm to 3 m. More closely spaced joints are locally developed adjacent to faults, defining fault damage zones that are no more than a few tens of meters wide about the principal-slip fault surfaces; joint spacings are relatively consistent elsewhere. Hudson et al, 2001Hudson et al, , 2006Hudson andMurray, 2003, 2004;Hudson and Turner, 2007Turner and Hudson, 2010). [Colour figure can be viewed at wileyonlinelibrary.com] The repetition of major lithologies in the long profile of the Buffalo River allows trends related to lithology to be compared in multiple reaches and enables those trends to be disentangled from factors that scale with discharge (e.g.…”

“…Longitudinal locations along the channel are designated as river kilometers (rkm) measured from the confluence of Reeves Fork and Big Buffalo Creek at the point where the river is designated as the Buffalo River on the Fallsville 1:24 000-scale USGS topographic quadrangle ( Figure 3). The study reach extends from rkm 17.0 on the Boxley quadrangle (Hudson and Turner, 2007) to rkm 172.1 at the western margin of the Maumee quadrangle and was selected owing to the availability of 1:24 k-scale geologic maps and the lack of accessibility in the lower reaches of the river (Figure 3). The study reach was partitioned into lithologic reaches defined by the dominant lithology making up the lower valley walls adjacent to the modern river and floodplain identified on 1:24 000-scale geologic quadrangles from Boxley to Maumee (Hudson et al, 2001(Hudson et al, , 2006Hudson andMurray 2003, 2004;Braden et al, 2003aBraden et al, , 2003bBraden et al, , 2003cHudson and Turner, 2007;Hutto et al, 2008;Turner and Hudson, 2010;Hudson and Turner, 2014).…”

The influence of sandstone caprock material on bedrock channel steepness within a tectonically passive setting: Buffalo National River Basin, Arkansas, USA

“…The low strength and fissile nature of the shale facilitates landsliding that transports large boulders wasted from the outcropping sandstone down the hillslope and over large distances (hundreds of meters) into the channel. Landslide deposits that originate at the Bloyd Formation are common throughout the basin, and many of the larger deposits have been mapped [ Hudson and Turner , , , ]. The larger Bloyd clasts are abundant as lag deposits within the tributary channels that drain from the caprock (Figure a), and in some cases clasts are sufficiently large to dwarf the channel.…”

“…LSDTopotoolbox generates channels that are divided into evenly spaced nodes, each node containing values for elevation, position, drainage area, and channel steepness. Each node was associated with a lithology by spatially joining nodes with geologic polygons available from United States Geological Survey geological maps [ Hudson and Turner , , , ].…”