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A fine-grained, dark gray sedimentary rock, formed from silt and clay and similar to shale but without laminations.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˈmʌdˌstəʊn) or


(Geological Science) a dark grey clay rock similar to shale but with the lamination less well developed
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014



a clayey rock with the texture and composition of shale but little or no lamination.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
It is found that the red mudstone is mainly composed of clay minerals and clastic minerals by qualitative and semiqualitative analysis, and the percentage of mass content of various minerals in the red mudstone is shown in Table 2.
According to incomplete statistics, approximately 69% of the reservoir area suffered rockslide hazard during the impoundment of the Three Gorges Reservoir [10, 11], which is closely related to the rheological effect under water-rock interaction of the mudstone formation.
[5] studied pore structure characteristics and permeability of seven types of deep sedimentary rocks (i.e., mudstone, sandy mudstone, siltstone, fine sandstone, medium sandstones, coarse sandstone, and conglomerate) based on MIP measurement data.
The lowermost Ragavere Formation (Torremagi Member) is fine-grained, bioclastic wackestone and the upper part (Piilse Member) is composed of calcareous (lime-) mudstone (cryptocrystalline limestone).
The Curiosity rover has already found proof of ancient lakes in older, lower-lying rocks on Mars, according to reports, as well as a mudstone above Old Soaker.
This is particularly true when such structures are built in mudstone and sandstone, which are two most widely distributed rock types encountered in underground mines.
By drilling into Martian mudstone, the rover was able to identify thiophene, 2- and 3-methylthiophenes, methanethiol and dimethylsulfide that are all also present in Earth mudstone.
has give in the of its Six mounds of Redcar Mudstone would be stored on this land in the next two years - with three proposed on the Grangetown Prairie site, two lined up on the Warrenby landfill area and one of the metals recov-ery site.
Wang said that most people know that mangoes grown in this area of Tainan, with its chalk soil and mudstone, are the sweetest and most fragrant despite their smaller size, according to the news outlet.
Lithofacies include clast-supported massive boulder conglomerate (Gcm(a)), clast-supported massive cobble conglomerate (Gcm(b)), clast-supported pebble to cobble conglomerate (Gcm(c)), clast-supported pebble conglomerate (Gcm(d)), Matrix-supported pebble conglomerate (Gmm), trough cross-stratified pebbly sandstone (St), horizontally stratified sandstone (Sh), trough cross-stratified sandstone (St), ripple cross laminated sandstone (Sr), massive sandstone (Sm), siltstone (F), massive mudstone (Fm), massive variegated mudstone (Fmv).
For the study, 60 oil shale samples and 30 samples of other rocks (sandstone, mudstone shale, dolostone, limestone) were collected from four drillings: S0501, S1403, S2503 and W7601 (Fig.
For the mudstone study, Jennifer Eigenbrode (NASA Goddard) and colleagues heated pulverized rock to nearly 900[degrees]C (1,600[degrees]F), catching the gases released as the rock molecules underwent chemical reactions or broke down.