Subp. 4.
Geological materials.
A licensee must report the geological materials penetrated in
drilling an exploratory boring. The report must include the rock or sediment
types, color, and relative hardness. The grain size must be reported for
unconsolidated sediments and may be based on field observation without
technical size measurement. Descriptions must use terms contained in items A
and B, the Dictionary of Geological Terms, or ASTM Standard D2487-85.
A. Unconsolidated materials:
Diameter |
Material |
Millimeters |
Inches |
(1) Clay |
Up to 0.005 |
Up to 0.0002 |
(2) Silt |
0.005 to 0.062 |
0.0002 to 0.0025 |
(3) Fine sand |
0.062 to 0.250 |
0.0025 to 0.0100 |
(4) Medium sand |
0.250 to 0.500 |
0.0100 to 0.0200 |
(5) Coarse sand |
0.500 to 1.000 |
0.0200 to 0.0400 |
(6) Very coarse sand |
1.000 to 2.000 |
0.0400 to 0.0800 |
(7) Fine gravel |
2.000 to 4.000 |
0.0800 to 0.1600 |
(8) Coarse gravel |
4.000 to 62.500 |
0.1600 to 2.5000 |
(9) Cobbles |
62.500 to 250.000 |
2.5000 to 10.000 |
B.
Rock:
(1) basalt, which is a very
fine-grained, dark igneous rock, commonly black, dark gray, or dark red-brown,
in which the mineral grains cannot be distinguished with the unaided
eye;
(2) carbonate rock, which is a
sedimentary rock consisting of limestone, dolomite, or dolostone;
(3) dolomite or dolostone, which is a
sedimentary rock composed primarily of the mineral dolomite (calcium-magnesium
carbonate), which effervesces weakly in dilute hydrochloric acid;
(4) gabbro, which is a dark-colored, basic
intrusive igneous rock comprised principally of basic plagioclase (commonly
labradorite or bytownite) and clinopyroxene (augite);
(5) gneiss, which is a foliated rock formed
by regional metamorphism, in which bands or lenticles of granular minerals
alternate with bands or lenticles in which minerals having flaky or elongate
prismatic habits predominate;
(6)
granite, which is a coarse-grained, light-colored igneous rock in which quartz
constitutes 10 to 50 percent of the felsic components and in which the alkali
feldspar/total feldspar ratio is generally restricted to the range of 65 to 90
percent;
(7) iron formation, which
is a chemical sedimentary rock, typically thin-bedded or finely laminated,
containing at least 15 percent iron of sedimentary origin, and commonly but not
necessarily containing layers of chert;
(8) limestone, which is a sedimentary rock
composed primarily of the mineral calcite (calcium carbonate), which
effervesces freely in dilute hydrochloric acid;
(9) metasedimentary rock, which is a
sedimentary rock that shows evidence of having been subjected to
metamorphism;
(10) metavolcanic
rock, which is a volcanic rock that shows evidence of having been subjected to
metamorphism;
(11) quartzite, which
is a very hard sandstone, consisting chiefly of quartz grains that have been so
completely and solidly cemented with secondary silica that the rock breaks
across or through the grains rather than around them or a granoblastic
metamorphic rock consisting mainly of quartz, which is formed by
recrystallization of sandstone or chert by metamorphism;
(12) sandstone, which is a sedimentary rock
consisting of cemented or otherwise compacted sediment and composed
predominantly of sand-sized particles generally of quartz;
(13) schist, which is a strongly foliated
crystalline rock, formed by dynamic metamorphism, that can be readily split
into thin flakes or slabs due to the well-developed parallelism of more than 50
percent of the minerals;
(14)
shale, which is a sedimentary rock consisting of compacted or cemented silt and
clay;
(15) slate, which is a
fine-grained, hard, dark-colored metamorphic rock derived from shale and which
typically is gray and splits readily into flat pieces; and
(16) volcanic rock, which is generally a
finely crystalline or glassy igneous rock resulting from volcanic action at or
near the earth's surface.