Concentrations of all 50 elements in the HSSR data set are statistically summarized in table 1. The number of sample analyses varied from one element to another because of differences in laboratory procedures and special studies, as described earlier. Uranium had the largest number of analyses (13,087), although the data set contained a total of 13,124 samples. All elements except uranium had analyses with concentrations less than the reporting limit set by the laboratory. As shown in the third column of table 1, the reporting limit was fixed for some elements, such as the reporting limit of 0.05 percent for aluminum. For other elements, such as antimony, the reporting limit listed in table 1 is given as a range because the reporting limit varied from one sample to another. Reporting limits for a given element can vary because of matrix effects or other characteristics of the individual sample or analysis.
Data sets for 36 elements in table 1 had small to moderate (less than 50 percent) amounts of censored data. Censored values are those reported as "less than" the reporting limit. For each of these 36 elements, a probability plot was generated to estimate the distribution of the data below the reporting limit (Helsel and Hirsch, 1992, p. 357-375). On the probability plot, the line through the data above the highest reporting limit was extended below the reporting limit and used to estimate the distribution of the data below the reporting limit. More than 50 percent of the data for antimony, bismuth, cadmium, chloride, gold, molybdenum, niobium, selenium, silver, tantalum, terbium, tin, and tungsten were below the reporting limit. The data for those 13 elements are not discussed further in this report because the utility of the data is limited by the censored values.
The data set chosen for spatial analysis contained 25 elements that were analyzed more or less uniformly across the study unit: aluminum, barium, beryllium, calcium, cerium, chromium, cobalt, copper, hafnium, iron, lanthanum, lead, lithium, magnesium, manganese, nickel, potassium, scandium, sodium, strontium, thorium, titanium, uranium, vanadium, and zinc. There were 12,289 bed-sediment samples in the HSSR data with non-missing values for all 25 selected constituents. Results of the factor analysis were interpreted using geographic information systems technology to perform a spatial analysis that categorized each HSSR sampling site with respect to the geologic setting and ecoregion.
About 65 percent of the total variation in the chemistry of the bed sediment was explained by the first four factors (table 2). In order to determine how many factors to retain for further analysis, two objective criteria were used to compare the percentage of explained variance for each factor in the HSSR data with the percentage expected for a corresponding factor computed from a set of random data. Results for Preisendorfer and Barnett's (1977) rule N test are presented in table 2. Both the rule N test and Frontier's "broken-stick" method (Jackson, 1993) suggested that retention of 3 factors would provide the greatest amount of useful information with the fewest number of factors. The factors were then rotated as described previously in the methods section.
| Table 1.
Descriptive statistics for element concentrations in bed-sediment samples collected during the National Uranium Resource Evaluation (NURE), Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) Yellowstone River Basin,1974-79 [*, concentration in percent; all other concentrations in milligrams per kilogram (mg/kg); --, percentile not calculated; <, less than] | ||||||||
|
Element |
Number of analyses |
Reporting limit (mg/kg) |
Concentrations greater than reporting limit (percent) |
Concentration (mg/kg) for selected percentiles of analyses |
||||
|---|---|---|---|---|---|---|---|---|
|
95 |
75 |
50 (median) |
25 |
5 |
||||
|
Aluminum (Al) |
12,643 |
.05 * |
99 |
7.85 * |
6.37 * |
5.30 * |
4.36 * |
3.04 * |
|
Antimony (Sb) |
7,754 |
1 - 17 |
1 |
-- |
-- |
<2 |
-- |
-- |
|
Arsenic (As) |
957 |
5 - |
78 |
44 |
14 |
9.0 |
5.0 |
3.0 |
|
Barium (Ba) |
12,643 |
2 - 411 |
99 |
1,230 |
784 |
619 |
513 |
361 |
|
Beryllium (Be) |
12,486 |
1 |
97 |
3.0 |
2.0 |
2.0 |
1.0 |
1.0 |
|
Bismuth (Bi) |
7,778 |
5 |
15 |
-- |
-- |
<5.0 |
-- |
-- |
|
Boron (B) |
4,844 |
10 |
98 |
57 |
37 |
28 |
21 |
13 |
|
Cadmium (Cd) |
7,778 |
5 |
1 |
-- |
-- |
<5 |
-- |
-- |
|
Calcium (Ca) |
12,643 |
.0237 - .188 * |
99 |
5.57 * |
3.42 * |
2.18 * |
1.31 * |
0.58 * |
|
Cerium (Ce) |
12,632 |
7 - 15 |
99 |
101 |
67 |
56 |
48 |
36 |
|
Cesium (Cs) |
7,788 |
.4 - 7.4 |
76 |
5.4 |
3.5 |
2.5 |
1.2 |
1.2 |
|
Chloride (Cl) |
7,798 |
17 - 254 |
19 |
-- |
-- |
<87 |
-- |
-- |
|
Chromium (Cr) |
12,635 |
1 - 23 |
99 |
243 |
77 |
48 |
36 |
25 |
|
Cobalt (Co) |
12,632 |
.1 - 4.6 |
98 |
24.2 |
10.6 |
7.3 |
6.0 |
4.0 |
|
Copper (Cu) |
12,622 |
2 - 10 |
98 |
44 |
27 |
21 |
16 |
10 |
|
Dysprosium (Dy) |
7,799 |
1 - 4 |
99 |
6 |
4 |
4 |
3 |
2 |
|
Europium (Eu) |
7,788 |
.2 - .9 |
99 |
2.0 |
1.5 |
1.2 |
0.9 |
0.7 |
|
Gold (Au) |
7,788 |
.02 - .72 |
1 |
-- |
-- |
<.08 |
-- |
-- |
|
Hafnium (Hf) |
12,632 |
.9 - 15 |
65 |
20 |
9.3 |
5.5 |
5.5 |
3.9 |
|
Iron (Fe) |
12,635 |
.05 -* |
99 |
5.13 * |
2.75 * |
1.96 * |
1.46 * |
0.86 * |
|
Lanthanum (La) |
12,589 |
2 - 159 |
97 |
61 |
37 |
28 |
23 |
17 |
|
Lead (Pb) |
12,622 |
5 - 10 |
84 |
27 |
17 |
12 |
7.0 |
3.0 |
|
Lithium (Li) |
12,486 |
1 |
99 |
51 |
34 |
26 |
20 |
14 |
|
Lutetium (Lu) |
7,788 |
.1 - .4 |
93 |
0.6 |
0.4 |
0.3 |
0.3 |
0.1 |
|
Magnesium (Mg) |
12,643 |
.05 - 1.179 * |
99 |
4.11 * |
2.01 * |
1.36 * |
0.92 * |
0.52 * |
|
Manganese (Mn) |
12,643 |
4 |
99 |
948 |
544 |
347 |
264 |
157 |
|
Molybdenum (Mo) |
5,226 |
4 - 5 |
6 |
-- |
-- |
<4 |
-- |
-- |
|
Nickel (Ni) |
12,622 |
2 - 15 |
74 |
58 |
26 |
17 |
8.0 |
8.0 |
|
Niobium (Nb) |
12,622 |
4 - 20 |
39 |
-- |
-- |
<20 |
-- |
-- |
|
Phosphorus (P) |
4,844 |
5 |
99 |
848 |
618 |
517 |
441 |
347 |
|
Potassium (K) |
12,643 |
.02 - 1.084 * |
99 |
2.13 * |
1.65 * |
1.42 * |
1.22 * |
0.96 * |
|
Rubidium (Rb) |
7,791 |
6 - 123 |
59 |
81 |
53 |
33 |
20 |
20 |
|
Samarium (Sm) |
7,760 |
.3 - 9.9 |
97 |
8.9 |
5.5 |
4.5 |
3.6 |
2.0 |
|
Scandium (Sc) |
12,632 |
1 |
99 |
16.7 |
8.9 |
6.0 |
5.0 |
3.5 |
|
Selenium (Se) |
957 |
5 |
.1 |
-- |
-- |
<5 |
-- |
-- |
|
Silver (Ag) |
12,622 |
2 - 5 |
1 |
-- |
-- |
<5 |
-- |
-- |
|
Sodium (Na) |
12,643 |
.05 * |
99 |
2.16* |
1.27* |
.74* |
0.51* |
0.25* |
|
Strontium (Sr) |
12,642 |
1 - 931 |
58 |
871 |
490 |
274 |
130 |
94 |
|
Tantalum (Ta) |
7,436 |
1 - 7 |
2 |
-- |
-- |
<1 |
-- |
-- |
|
Terbium (Tb) |
7,502 |
1 - 3 |
3 |
-- |
-- |
<1 |
-- |
-- |
|
Thorium (Th) |
12,632 |
1.5 - 4.4 |
95 |
18.5 |
10.3 |
8.0 |
5.8 |
1.4 |
|
Tin (Sn) |
7,778 |
10 |
1 |
-- |
-- |
<10 |
-- |
-- |
|
Titanium (Ti) |
12,643 |
10 - 2,585 |
99 |
5,080 |
3,370 |
2,620 |
2,050 |
1,540 |
|
Tungsten (W) |
7,778 |
15 |
4 |
-- |
-- |
<15 |
-- |
-- |
|
Uranium (U) |
13,087 |
0.01 |
100 |
5.5 |
3.4 |
2.8 |
2.5 |
1.7 |
|
Vanadium (V) |
12,643 |
2 - 31 |
99 |
161 |
92 |
64 |
50 |
35 |
|
Ytterbium (Yb) |
7,765 |
.5 - 6.3 |
77 |
5.3 |
3.4 |
2.7 |
1.7 |
1.4 |
|
Yttrium (Y) |
4,844 |
1 |
99 |
16 |
13 |
11 |
10 |
8.0 |
|
Zinc (Zn) |
12,546 |
4 - 204 |
77 |
127 |
111 |
72 |
50 |
33 |
|
Zirconium (Zr) |
5,801 |
2 |
99 |
214 |
76 |
60 |
51 |
42 |
| Table 2. Percentage of variance explained by first four unrotated factors, and comparison with percentages computed from a set of random data | |||||
|
Factor |
Sediment chemistry variance explained, in percent |
Cumulative variance explained, in percent |
Random data variance explained, in percent1 |
Result for rule N test2 |
|
|---|---|---|---|---|---|
|
1 |
38.3 |
38.3 |
7.7 |
p <0.05 |
|
|
2 |
12.2 |
50.5 |
7.3 |
p<0.05 |
|
|
3 |
8.2 |
58.7 |
7.1 |
p<0.05 |
|
|
4 |
6.2 |
64.9 |
6.9 |
p<0.05 |
|
1Computed for a matirx with 25
constituents.
2See Preisendorfer and Barnett (1977) for description of rule N
tests.
The three factors identified in the factor analysis correspond to three geochemically distinct types of source rocks. Factors 1 and 2 reflect the influence of two types of igneous source rocks: basaltic (mafic) and granitic (felsic). Factor 3 reflects sedimentary rocks, carbonate rocks in particular.
Factor 1 largely reflects the influence of basaltic rocks, based on the correlated elements and spatial distribution of the factor scores. Factor 1 is correlated with scandium, iron, cobalt, vanadium, chromium, aluminum, nickel, manganese, copper, titanium, sodium, barium, strontium, and zinc in descending order of strength of positive correlation. Scandium, iron, cobalt, and vanadium strongly correlate (r > 0.85) with factor 1. Ten of the 14 elements associated with factor 1 share similar properties. Scandium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, and copper are on average at least four times more abundant in basaltic rocks than in granitic rocks, and zinc is about twice as abundant (Mason, 1966, p. 45-48). The chemical similarity of the same 10 elements can be noted from the periodic chart of the elements, where they are B-subgroup elements, atomic numbers 21-30, and are transition elements adjacent to each other in the period-4 element row. The other elements, aluminum, sodium, barium, and strontium, associated with factor 1 are present, on average, in equal or greater abundance in granite than basalt (Mason, 1966, p. 45-48), and are A-subgroup elements of the periodic table. Elements of the A subgroup have considerably lower electronegativities than elements of the B-subgroup, which has an important influence on bonding and distribution of the elements during magmatic crystallization (Mason, 1966, p. 133). The use of factor analysis, therefore, was useful in determining an association of aluminum, sodium, barium, and strontium with period-4 metals that would not be predicted from either average abundance data from Mason (1966) or from associations on the periodic chart.
Scores for factor 1 tended to be highest in the western part of the YRB (plate 2), in areas of volcanic rocks of Tertiary and Cretaceous age (Absaroka volcanic field) and crystalline rocks of Precambrian age in the Beartooth Mountains. High factor scores (greater than 1, for example) on plate 2 indicate the strongest associations of the data with factor 1. Andesite and dacite are the primary rock types in the Absaroka volcanic field (Chadwick, 1970), which corroborates the influence of basaltic rocks on factor 1. The high factor-1 scores in the Beartooth Mountains might reflect the intrusions, veins, and other geologic features within the area, rather than the host crystalline rock. Outside the Beartooth Mountains, samples from areas of crystalline rocks of Precambrian age had intermediate scores on factor 1. The lowest factor-1 scores tended to be from samples collected from sedimentary rocks of Tertiary, Cretaceous, and Paleozoic age.
The distribution of the elements is controlled in part by their chemical properties and behavior. Numerous igneous rock minerals are sources of iron, but iron concentrations can be several times larger in basaltic rocks than in granitic rocks (Mason, 1966, p. 45). Ferromagnesian minerals commonly dissolve during weathering and reprecipitate as sedimentary minerals (Hem, 1985, p. 77). Iron also is a common component in sulfide ores of other metals. Cobalt is most abundant in igneous rocks, particularly basaltic rocks (Mason, 1966, p. 45), and cobalt ions can substitute for part of the iron in ferrogmagnesian rock minerals (Hem, 1985, p. 138). Chromium is most abundant in ultramafic or basaltic rocks, and chromite (highly resistant to weathering) is common in residue overlying ultramafic rocks (Hem, 1985, p. 138). Weathering of igneous rocks commonly produces sediment enriched in aluminum; the most common of the aluminum-enriched minerals are clays (Hem, 1985, p. 73). Aluminum is about equally abundant in granitic and basaltic rocks (Mason, 1966, p. 45). Manganese is a minor constituent in many igneous and metamorphic minerals, and is most abundant in basaltic rocks (Mason, 1966, p. 45). When dissolved during weathering in an oxidizing environment, manganese generally will reprecipitate as a crust of manganese oxide in association with iron and sometimes substantial amounts of other metal ions (Hem, 1985, p. 86). Copper occurs in sulfide minerals and in ore minerals that also contain iron (Hem, 1985, p. 141). Titanium is commonly associated with iron in minerals that are highly resistant to weathering and therefore tend to persist in sediments (Hem, 1985, p. 137). Titanium forms specific minerals that are widely dispersed throughout some of the commonest rocks (Mason, 1966, p. 49), which helps explain why concentrations of titanium in bed sediment are large relative to many of the other elements (table 1). Barium, sodium, and strontium are more abundant in granitic rocks than basaltic rocks (Mason, 1966, p. 45-46). Zinc has about the same abundance in crustal rocks as copper or nickel and is fairly common (Hem, 1985, p 142).
Factor 2 reflects the influence of granitic rocks. Factor 2 correlates with thorium, lanthanum, cerium, beryllium, hafnium, uranium, and potassium, in descending order of strength of positive correlation. Correlation coefficients ranged from 0.78 to 0.52. The average abundance of the seven elements associated with factor 2 is several times greater in granite than in basalt (Mason, 1966, p. 45-48).
Factor-2 scores were highest in samples from volcanic rocks of Quaternary age (Yellowstone Plateau). Rhyolite, which is the extrusive equivalent of granite, predominates in the volcanic rocks of the Yellowstone Plateau. Factor-2 scores were intermediate from areas of crystalline rocks of Precambrian age, both in and outside the Beartooth Mountains. The crystalline rocks of Precambrian age in the study unit are exposed at the cores of structural uplifts in the Beartooth Mountains, the Wind River Range, the Bighorn Mountains, the Owl Creek Mountains, and the Bridger Mountains (plate 1). Outcrops of granitic rocks also occur in the Granite Mountains that lie just south of the study unit and contributed basin-fill debris to the Wind River structural basin.
The lowest scores on factor 2 were associated with sedimentary rocks, with the exception of the intermediate-level scores associated with sedimentary rocks of Tertiary age in the Wyoming Basin ecoregion. Factor-2 scores for sedimentary rocks of Tertiary age were significantly different (Mann-Whitney test, probability 0.05, Iman and Conover, 1983) in the Wyoming Basin ecoregion than for the same geologic setting in the Northwestern Great Plains ecoregion. The difference in factor-2 scores between the two ecoregions might be caused by differences in environmental components or processes related to the ecoregion such as source rocks and weathering rates. Using data from two analytical laboratories probably did not cause the differences in factor-2 scores between the ecoregions, for samples from areas of rocks of Tertiary age. Testing of data from Los Alamos Scientific Laboratory in comparison with data from Oak Ridge National Laboratory on samples collected in areas of sedimentary rocks of Tertiary age indicated the concentrations were not significantly different between the laboratories (Mann-Whitney, probability 0.05). A similar test was applied to data from areas of sedimentary rocks of Cretaceous age, which indicated a small but significant difference in median test scores for samples from areas of rocks of Cretaceous age between the laboratories, but not between the two ecoregions.
Factor 3 is associated most strongly with carbonate rocks. Factor 3 correlates positively with magnesium and calcium (r > 0.75). Both of these elements are usually far more abundant in carbonate rocks than in other rock types, and in combination with carbon are the chief components of carbonate rocks, on average (Hem, 1985, p. 5). Strontium has a chemistry similar to that of calcium, is typically most abundant in carbonate rocks, and had the third strongest positive correlation with factor 3. Lead was intermediate between magnesium and calcium in correlations with factors 1 and 2, but was strongly and negatively correlated (r = -0.64) with factor 3.
Samples from sedimentary rocks of Paleozoic age and volcanic rocks of Tertiary and Cretaceous age had higher scores on factor 3 than did samples from other settings. The sedimentary rocks of Paleozoic age that are exposed along the flanks of the Bighorn Mountains and other structural uplifts in the study unit are primarily carbonates such as limestone and dolomite. Samples from areas of crystalline rocks of Precambrian age in and outside of the Beartooth Mountains and sedimentary rocks of Tertiary age outside the Wyoming Basin ecoregion tended to have lower factor-3 scores than those from other geologic settings.
Summary statistics for all 50 elements analyzed from HSSR bed sediment samples in the Yellowstone River Basin are listed in table 1. Summary statistics also are presented for the 25 elements used in the factor analysis, in eight geologic settings: table 3, volcanic rocks of Quaternary age (Yellowstone Plateau); table 4, volcanic rocks of Tertiary and Cretaceous age (Absaroka volcanic field); table 5, sedimentary rocks of Tertiary age in the Wyoming Basin ecoregion; table 6, sedimentary rocks of Tertiary age outside of the Wyoming Basin ecoregion; table 7, sedimentary rocks of Cretaceous age; table 8, sedimentary rocks of Paleozoic age; table 9, crystalline rocks of Precambrian age in the Beartooth Mountains; and table 10, crystalline rocks of Precambrian age outside the Beartooth Mountains.
Smith and others (1996) summarized sediment-quality assessment values (SQAV) for the protection of aquatic life. The SQAV were developed using multiple lines of evidence, including biological and chemical data from modeling, laboratory tests, and field studies. The assessment values included a probable effect level (PEL) above which toxic effects are frequently noted, and an effects range median (ERM) (Long and others, 1995) which is the median concentration at which adverse effects were noted. Although the ERM concentrations are based on marine and estuarine sediment, Ingersoll and others (1996) considered ERMs to be as reliable as PELs for classifying freshwater sediments as either toxic or nontoxic. Kemble and others (1998) also noted that ERMs were highly reliable for classifying sediment from the upper Mississippi River as toxic or nontoxic.
The SQAV are based on bulk sediment, whereas the HSSR data are from sieved samples. The effect of sieving likely increases trace-element concentrations relative to the bulk fraction, because the trace elements generally are associated with the smaller particles (Horowitz, 1991, p. 16-22; Peterson and others, 1991). Comparison of the SQAV with the sieved data from HSSR is intended only as a point of reference and not as an absolute indication of the occurrence of toxic effects.
More than 99 percent of the copper, lead, and zinc concentrations and more than 75 percent of the chromium and nickel concentrations in the HSSR samples were less than the corresponding PEL and ERM (table 11). The highest concentrations of copper, zinc, chromium, and nickel generally occurred in samples from the western part of the study unit, as shown for copper in plate 3. Copper concentrations in bed sediment were highest in samples from crystalline rocks of Precambrian age in the Beartooth Mountains and volcanic rocks of Tertiary and Cretaceous age, as shown in the boxplots on plate 3.
Gurrieri (1998) described high concentrations of trace elements and associated adverse effects on the benthic invertebrate and periphyton communities of the Stillwater River. The headwaters of the Stillwater River, where the effects were noted, are in the Precambrian crystalline rocks of the Beartooth Mountains (plate 1). Concentrations of copper in bed-sediment samples collected where adverse effects were noted, downstream of an area affected by mining, were 5,617 and 4,820 mg/kg (Gurrieri, 1998). Lesser effects to the aquatic life were noted farther downstream, where copper concentrations ranged from 254 to 521 mg/kg (Gurrieri, 1998). The background copper concentration in bed-sediment samples (sieved through 60 micron mesh) from the upper Stillwater River basin was 353 mg/kg (Gurrieri, 1998), which is higher than both the PEL and the ERM.
Nimmo and others (1998) described toxicity to the amphipod Hyallela azteca (a surrogate test organism) in 7-day long toxicity tests with whole bed sediment and interstitial pore water from Soda Butte Creek in the vicinity of Yellowstone National Park (plate 3). Survival of the amphipods was nearly zero from all sites on Soda Butte Creek downstream of mine tailings and from a naturally mineralized creek where mining never occurred. The toxicity was attributed to copper (Nimmo and others, 1998, p. 924). The copper concentrations in bed sediment associated with the toxicity in Soda Butte Creek generally ranged from about 100 to 500 mg/kg (Nimmo and others, 1998, p. 923).
|
Table 3. Summary statistics for element concentrations in bed-sediment samples collected from streams in areas of volcanic rocks of Quaternary age (Yellowstone Plateau), Yellowstone River Basin,1974-79 [*, concentration in percent, all other concentrations in milligrams per kilogram (mg/kg); <, less than. Statistics calculated from 151 samples] | |||||
| Element | Concentration (mg/kg) for selected percentiles of analyses | ||||
|---|---|---|---|---|---|
| 95 | 75 |
50 |
25 |
5 |
|
|
Aluminum (Al) |
7.72 * |
6.97 * |
6.41 * |
5.97 * |
4.26 * |
|
Barium (Ba) |
1,590 |
939 |
786 |
629 |
450 |
|
Beryllium (Be) |
5.5 |
4.0 |
3.0 |
2.0 |
1.0 |
|
Calcium (Ca) |
4.06 * |
2.66 * |
2.04 * |
1.15 * |
43 * |
|
Cerium (Ce) |
158 |
120 |
98.0 |
81.5 |
45.0 |
|
Chromium (Cr) |
299 |
173 |
114 |
63.5 |
33.0 |
|
Cobalt (Co) |
23.4 |
14.5 |
9.8 |
5.4 |
0.8 |
|
Copper (Cu) |
65.5 |
37.0 |
22.0 |
14.5 |
4.5 |
|
Hafnium (Hf) |
22.4 |
12.8 |
10.1 |
7.8 |
4.4 |
|
Iron (Fe) |
5.03 * |
3.31 * |
2.49 * |
1.83 * |
0.96 * |
|
Lanthanum (La) |
93.0 |
66.5 |
55.0 |
43.5 |
25.0 |
|
Lead (Pb) |
32.5 |
20.5 |
14.0 |
10.0 |
4.0 |
|
Lithium (Li) |
56.0 |
45.0 |
39.0 |
30.0 |
13.0 |
|
Magnesium (Mg) |
5.00 * |
2.79 * |
1.98 * |
1.06 * |
0.11 * |
|
Manganese (Mn) |
1,180 |
690 |
518 |
391 |
161 |
|
Nickel (Ni) |
59.0 |
33.5 |
22.0 |
8.0 |
8.0 |
|
Potassium (K) |
2.88 * |
2.33 * |
1.98 * |
1.63 * |
1.06 * |
|
Scandium (Sc) |
18.5 |
11.6 |
8.7 |
6.1 |
4.4 |
|
Sodium (Na) |
2.25 * |
1.97 * |
1.79 * |
1.31 * |
0.73 * |
|
Strontium (Sr) |
786 |
541 |
490 |
490 |
452 |
|
Thorium (Th) |
21.9 |
16.8 |
13.9 |
11.0 |
5.2 |
|
Titanium (Ti) |
4,890 |
3,840 |
3,270 |
2,750 |
2,060 |
|
Uranium (U) |
5.67 |
4.16 |
3.31 |
2.72 |
1.61 |
|
Vanadium (V) |
137 |
85.0 |
58.0 |
39.5 |
20.5 |
|
Zinc (Zn) |
166 |
121 |
111 |
111 |
54.5 |
|
Table 4. Summary statistics for element
concentrations in bed-sediment samples collected from
streams in areas of volcanic rocks of Tertiary and
Cretaceous age (Absaroka volcanic field), Yellowstone River Basin, 1974-79 [*, concentration in percent; all other concentrations in milligrams per kilogram (mg/kg); <, less than. Statistics calculated from 1,276 samples] | |||||
| Element | Concentration (mg/kg) for selected percentiles of analyses | ||||
|---|---|---|---|---|---|
| 95 | 75 | 50 (median) | 25 | 5 | |
|
Aluminum (Al) |
8.37 * |
7.85 * |
7.20 * |
6.49 * |
5.49 * |
|
Barium (Ba) |
1,460 |
1,180 |
968 |
822 |
620 |
|
Beryllium (Be) |
3.0 |
2.0 |
2.0 |
2.0 |
0.7 |
|
Calcium (Ca) |
5.48 * |
4.39 * |
3.55 * |
2.74 * |
1.69 * |
|
Cerium (Ce) |
113 |
83.0 |
69.5 |
60.0 |
48.0 |
|
Chromium (Cr) |
395 |
230 |
163 |
117 |
49.0 |
|
Cobalt (Co) |
33.6 |
24.6 |
18.1 |
14.3 |
9.6 |
|
Copper (Cu) |
57.3 |
39.0 |
31.0 |
24.0 |
17.0 |
|
Hafnium (Hf) |
18.8 |
9.1 |
5.7 |
3.9 |
2.8 |
|
Iron (Fe) |
7.66 * |
5.18 * |
4.18 * |
3.50 * |
2.57 * |
|
Lanthanum (La) |
67.0 |
46.0 |
39.0 |
34.0 |
23.0 |
|
Lead (Pb) |
20.0 |
13.0 |
10.0 |
6.0 |
3.0 |
|
Lithium (Li) |
43.0 |
32.0 |
25.0 |
20.0 |
13.0 |
|
Magnesium (Mg) |
5.87 * |
4.09 * |
2.45 * |
1.28 * |
0.84 * |
|
Manganese (Mn) |
1,170 |
879 |
726 |
608 |
473 |
|
Nickel (Ni) |
91.0 |
52.0 |
35.0 |
21.8 |
8.0 |
|
Potassium (K) |
2.07 * |
1.72 * |
1.49 * |
1.27 * |
0.94 * |
|
Scandium (Sc) |
26.4 |
16.7 |
12.8 |
10.5 |
7.9 |
|
Sodium (Na) |
2.46 * |
2.15 * |
1.88 * |
1.47 * |
1.07 * |
|
Strontium (Sr) |
1,210 |
917 |
672 |
490 |
410 |
|
Thorium (Th) |
16.5 | 9.8 | 7.8 | 5.9 | 3.9 |
| Titanium (Ti) | 6,790 | 4,920 | 4,160 | 3,480 | 2,820 |
| Uranium (U) | 3.80 | 2.66 | 2.11 | 1.60 | 1.08 |
| Vanadium (V) | 263 | 157 | 123 | 100 | 72.0 |
| Zinc (Zn) | 156 | 114 | 111 | 96.0 | 57.8 |
| Table 5. Summary statistics for element concentrations in bed-sediment samples collected from streams in areas of sedimentary rocks of Tertiary age, in Wyoming Basin
ecoregion, Yellowstone River Basin, 1974-79 [*, concentration in percent; all other concentrations in milligrams per kilogram (mg.kg); <, less than. Statistics calculated from 1,584 samples] | |||||
|
Element |
Concentration (mg/kg) for selected percentiles of analyses |
||||
|---|---|---|---|---|---|
|
95 |
75 |
50 (median) |
25 |
5 |
|
|
Aluminum (Al) |
7.86 * |
6.02 * |
5.07 * |
3.87 * |
2.30 * |
|
Barium (Ba) |
1,310 |
718 |
609 |
522 |
410 |
|
Beryllium (Be) |
3.0 |
2.0 |
2.0 |
2.0 |
1.0 |
|
Calcium (Ca) |
4.53 * |
2.83 * |
1.98 * |
1.14 * |
.44 * |
|
Cerium (Ce) |
119 |
75.0 |
63.0 |
52.0 |
40.0 |
|
Chromium (Cr) |
143 |
67.0 |
51.0 |
39.0 |
27.0 |
|
Cobalt (Co) |
17.0 |
9.1 |
6.9 |
5.4 |
3.8 |
|
Copper (Cu) |
36.0 |
26.0 |
20.0 |
15.0 |
9.0 |
|
Hafnium (Hf) |
25.2 |
13.8 |
9.7 |
7.0 |
4.6 |
|
Iron (Fe) |
3.66 * |
2.26 * |
1.61 * |
1.18 * |
0.74 * |
|
Lanthanum (La) |
110 |
45.0 |
35.0 |
28.0 |
20.0 |
|
Lead (Pb) |
21.0 |
14.0 |
10.0 |
7.0 |
3.0 |
|
Lithium (Li) |
47.0 |
34.2 |
26.0 |
20.0 |
13.0 |
|
Magnesium (Mg) |
3.08 * |
2.00 * |
1.52 * |
1.07 * |
0.51 * |
|
Manganese (Mn) |
655 |
445 |
345 |
262 |
154 |
|
Nickel (Ni) |
40.0 |
22.0 |
8.0 |
8.0 |
8.0 |
|
Potassium (K) |
2.17 * |
1.78 * |
1.53 * |
1.31 * |
1.05 * |
|
Scandium (Sc) |
12.1 |
7.6 |
5.9 |
4.7 |
3.3 |
|
Sodium (Na) |
2.10 * |
1.22 * |
0.80 * |
0.40 * |
.18 * |
|
Strontium (Sr) |
744 |
490 |
466 |
130 |
130 |
|
Thorium (Th) |
28.7 |
13.7 |
10.3 |
8.1 |
5.8 |
|
Titanium (Ti) |
4,870 |
3,460 |
2,900 |
2,460 |
1,880 |
|
Uranium (U) |
6.27 |
3.78 |
3.13 |
2.70 |
2.10 |
|
Vanadium (V) |
114 |
68.0 |
54.0 |
44.0 |
31.0 |
|
Zinc (Zn) |
111 |
111 |
76.0 |
52.0 |
28.0 |
| Table 6.
Summary statistics for element concentrations in bed-sediment samples collected from streams in areas of sedimentary rocks of Tertiary age, in Wyoming Basin
ecoregion, Yellowstone River Basin, 1974-79 [*, concentration in percent; all other concentrations in milligrams per kilogram (mg/kg); <, less than. Statistics calculated from 3,451 samples] | |||||
| Element | Concentration (mg/kg) for selected percentiles of analyses | ||||
|---|---|---|---|---|---|
| 95 | 75 | 50 (median) | 25 | 5 | |
| Aluminum (Al) | 7.05 * | 5.60 * | 4.80 * | 4.19 * | 3.44 * |
| Barium (Ba) | 957 | 673 | 578 | 50 | 423 |
| Beryllium (Be) | 2.0 | 1.0 | 1.0 | 1.0 | 1.0 |
| Calcium (Ca) | 4.76 * | 2.95 * | 1.76 * | 1.12 * | 0.46 * |
| Cerium (Ce) | 71.0 | 58.0 | 52.0 | 46.0 | 37.0 |
| Chromium (Cr) | 91.0 | 49.0 | 40.0 | 33.0 | 24.5 |
| Cobalt (Co) |
11.2 |
8.0 |
7.0 |
5.6 |
4.0 |
|
Copper (Cu) |
35.0 |
24.0 |
19.0 |
15.0 |
10.0 |
|
Hafnium (Hf) |
19.0 |
5.5 |
5.5 |
5.5 |
5.5 |
|
Iron (Fe) |
2.90 * |
2.18 * |
1.87 * |
1.56 * |
1.04 * |
|
Lanthanum (La) |
40.0 |
28.0 |
24.0 |
21.0 |
17.0 |
|
Lead (Pb) |
27.0 |
20.0 |
15.0 |
10.0 |
5.5 |
|
Lithium (Li) |
39.0 |
28.0 |
23.0 |
19.0 |
14.0 |
|
Magnesium (Mg) |
2.17 * |
1.59 * |
1.12 * |
0.75 * |
0.47 * |
|
Manganese (Mn) |
578 |
368 |
305 |
253 |
166 |
|
Nickel (Ni) |
37.0 |
22.0 |
17.0 |
12.0 |
8.0 |
|
Potassium (K) |
1.83 * |
1.51 * |
1.33 * |
1.19 * |
0.98 * |
|
Scandium (Sc) |
9.0 |
7.0 |
5.6 |
5.0 |
4.0 |
|
Sodium (Na) |
1.16 * |
0.68 * |
0.55 * |
0.42 * |
0.20 * |
|
Strontium (Sr) |
491 |
219 |
144 |
111 |
77 |
|
Thorium (Th) |
13.0 |
9.0 |
6.8 |
4.0 |
1.4 |
|
Titanium (Ti) |
3,440 |
2,490 |
2,040 |
1,780 |
1,440 |
|
Uranium (U) |
4.30 |
3.10 |
2.80 |
2.60 |
2.20 |
|
Vanadium (V) |
99.0 |
70.0 |
57.0 |
48.0 |
38.0 |
|
Zinc (Zn) |
111 |
70.0 |
54.0 |
45.0 |
33.0 |
| Table 7.
Summary statistics for element concentrations in bed-sediment samples collected from streams in areas of sedimentary rocks of Cretaceous age, Yellowstone River Basin, 1974-79 [*, concentration in percent; all other concentrations in milligrams per kilogram (mg/kg); <, less than. Statistics calculated from 3,698 samples] | |||||
|---|---|---|---|---|---|
|
Element |
Concentration (mg/kg) for selected percentiles of analyses |
||||
|
95 |
75 |
50 (median) |
25 |
5 |
|
|
Aluminum (Al) |
7.25 * |
5.96 * |
5.17 * |
4.41 * |
3.18 * |
|
Barium (Ba) |
1,000 |
738 |
624 |
528 |
407 |
|
Beryllium (Be) |
3.0 |
2.0 |
2.0 |
1.0 |
1.0 |
|
Calcium (Ca) |
5.13 * |
2.93 * |
1.89 * |
1.22 * |
0.60 * |
|
Cerium (Ce) |
78.0 |
61.0 |
54.0 |
47.0 |
36.0 |
|
Chromium (Cr) |
107 |
58.0 |
44.0 |
34.0 |
24.0 |
|
Cobalt (Co) |
13.0 |
8.7 |
7.0 |
5.4 |
3.7 |
|
(Cu) |
34.0 |
24.0 |
19.0 |
15.0 |
9.0 |
|
Hafnium (Hf) |
17.4 |
8.1 |
5.5 |
5.5 |
4.5 |
|
Iron (Fe) |
3.28 * |
2.27 * |
1.79 * |
1.32 * |
0.84 * |
|
Lanthanum (La) |
43.0 |
32.0 |
27.0 |
23.0 |
18.0 |
|
Lead (Pb) |
27.0 |
18.0 |
12.0 |
7.0 |
3.0 |
|
Lithium (Li) |
58.0 |
38.0 |
28.0 |
22.0 |
15.0 |
|
Magnesium (Mg) |
2.89 * |
1.81 * |
1.24 * |
0.88 * |
0.52 * |
|
Manganese (Mn) |
717 |
388 |
294 |
231 |
137 |
|
Nickel (Ni) |
34.0 |
22.0 |
16.0 |
8.0 |
8.0 |
|
Potassium (K) |
2.00 * |
1.60 * |
1.38 * |
1.21 * |
0.99 * |
|
Scandium (Sc) |
10.5 |
7.2 |
6.0 |
5.0 |
3.4 |
|
Sodium (Na) |
1.51 * |
1.00 * |
0.74 * |
0.55 * |
0.33 * |
|
Strontium (Sr) |
503 |
490 |
207 |
130 |
106 |
|
Thorium (Th) |
13.0 |
9.4 |
7.6 |
5.7 |
1.4 |
|
Titanium (Ti) |
3,980 |
2,930 |
2,440 |
2,060 |
1,600 |
|
Uranium (U) |
4.53 |
3.40 |
2.90 |
2.60 |
2.09 |
|
Vanadium (V) |
145 |
92.0 |
68.0 |
52.0 |
38.0 |
|
Zinc (Zn) |
111 |
103 |
70.0 |
51.0 |
34.0 |
| Table 8.
Summary statistics for element concentrations in bed-sediment samples collected from streams in areas of sedimentary rocks of Paleozoic age, Yellowstone River Basin, 1974-79
[*, concentration in percent; all other concentrations in milligrams per kilogram (mg/kg); <, less than. Statistics calculated from 1,249 samples] |
|||||
|
Element |
Concentration (mg/kg) for selected percentiles of analyses |
||||
|---|---|---|---|---|---|
|
95 |
75 |
50 (median) |
25 |
5 |
|
|
Aluminum (Al) |
7.37 * |
5.64 * |
4.54 * |
3.65 * |
2.08 * |
|
Barium (Ba) |
1,120 |
650 |
478 |
356 |
249 |
|
Beryllium (Be) |
3.0 |
2.0 |
2.0 |
1.0 |
0.7 |
|
Calcium (Ca) |
9.19 * |
5.24 * |
3.81 * |
2.01 * |
.71 * |
|
Cerium (Ce) |
93.0 |
65.0 |
51.0 |
39.0 |
22.4 |
|
Chromium (Cr) |
180 |
65.0 |
46.0 |
35.0 |
22.0 |
|
Cobalt (Co) |
22.0 |
9.2 |
7.0 |
5.3 |
3.0 |
|
Copper (Cu) |
38.0 |
26.0 |
20.0 |
15.0 |
7.0 |
|
Hafnium (Hf) |
17.0 |
10.1 |
7.5 |
5.5 |
3.9 |
|
Iron (Fe) |
4.79 * |
2.37 * |
1.58 * |
1.07 * |
0.60 * |
|
Lanthanum (La) |
50.0 |
35.0 |
27.0 |
20.0 |
9.0 |
|
Lead (Pb) |
23.0 |
13.0 |
8.0 |
5.0 |
3.0 |
|
Lithium (Li) |
73.0 |
38.0 |
29.0 |
22.0 |
13.0 |
|
Magnesium (Mg) |
5.35 * |
3.08 * |
2.06 * |
1.25 * |
0.62 * |
|
Manganese (Mn) |
936 |
550 |
387 |
283 |
132 |
|
Nickel (Ni) |
43.0 |
21.0 |
15.0 |
8.0 |
8.0 |
|
Potassium (K) |
2.59 * |
1.76 * |
1.51 * |
12.6 * |
0.86 * |
|
Scandium (Sc) |
15.4 |
7.8 |
6.0 |
4.5 |
2.7 |
|
Sodium (Na) |
1.97 * |
0.92 * |
0.68 * |
0.46 * |
0.21 * |
|
Strontium (Sr) |
826 |
490 |
490 |
147 |
119 |
|
Thorium (Th) |
15.8 |
9.7 |
7.4 |
5.6 |
2.8 |
|
Titanium (Ti) |
4,910 |
3,390 |
2,820 |
2,150 |
1,170 |
|
Uranium (U) |
4.45 |
2.98 |
2.46 |
2.09 |
1.50 |
|
Vanadium (V) |
144 |
69.0 |
53.0 |
41.0 |
26.0 |
|
Zinc (Zn) |
120 |
111 |
77.0 |
47.0 |
20.0 |
| Table 9.
Summary statistics for element concentrations in bed-sediment samples collected from streams in areas of crystalline rocks of Precambrian age, in the Beartooth Mountains, Yellowstone River Basin, 1974-79
[*, concentration in percent; all other concentrations in milligrams per kilogram (mg/kg); <, less than. Statistics calculated from 692 samples] | |||||
|
Element |
Concentration (mg/kg) for selected percentiles of analyses |
||||
|---|---|---|---|---|---|
|
95 |
75 |
50 (median) |
25 |
5 |
|
|
Aluminum (Al) |
7.78 * |
7.07 * |
6.57 * |
6.11 * |
4.97 * |
|
Barium (Ba) |
1,400 |
957 |
680 |
460 |
246 |
|
Beryllium (Be) |
3.0 |
2.0 |
2.0 |
1.0 |
0.7 |
|
Calcium (Ca) |
4.18 * |
3.04 * |
2.20 * |
1.60 * |
0.98 * |
|
Cerium (Ce) |
166 |
93.0 |
73.0 |
58.0 |
37.6 |
|
Chromium (Cr) |
644 |
232 |
140 |
89.0 |
53.0 |
|
Cobalt (Co) |
36.2 |
23.3 |
15.9 |
11.4 |
6.4 |
|
Copper (Cu) |
89.9 |
46.0 |
31.0 |
23.8 |
15.0 |
|
Hafnium (Hf) |
20.8 |
10.3 |
7.1 |
5.2 |
3.5 |
|
Iron (Fe) |
6.85 * |
4.81 * |
3.70 * |
2.70 * |
1.47 * |
|
Lanthanum (La) |
118 |
59.0 |
44.0 |
35.0 |
21.0 |
|
Lead (Pb) |
44.5 |
21.0 |
14.0 |
9.0 |
3.0 |
|
Lithium (Li) |
63.0 |
44.0 |
34.0 |
24.0 |
13.0 |
|
Magnesium (Mg) |
4.72 * |
2.09 * |
1.53 * |
1.07 * |
0.61 * |
|
Manganese (Mn) |
1,240 |
926 |
729 |
586 |
334 |
|
Nickel (Ni) |
180 |
62.0 |
36.0 |
23.0 |
8.0 |
|
Potassium (K) |
2.28 * |
1.75 * |
1.39 * |
1.11 * |
0.69 * |
|
Scandium (Sc) |
21.9 |
15.6 |
11.8 |
9.4 |
6.5 |
|
Sodium (Na) |
2.67 * |
2.08 * |
1.69 * |
1.35 * |
0.79 * |
|
Strontium (Sr) |
822 |
490 |
490 |
490 |
463 |
|
Thorium (Th) |
42.9 |
18.0 |
12.4 |
9.2 |
5.8 |
|
Titanium (Ti) |
5,930 |
4,260 |
3,460 |
2,850 |
1,990 |
|
Uranium (U) |
44.8 |
12.3 |
4.40 |
2.80 |
1.68 |
|
Vanadium (V) |
209 |
122 |
95.0 |
74.8 |
52.0 |
|
Zinc (Zn) |
162 |
111 |
111 |
96.0 |
53.0 |
| Table 10.
Summary statistics for element concentrations in bed-sediment samples collected from streams in areas of crystalline rocks of Precambrian age, outside of the Beartooth Mountains, Yellowstone River Basin, 1974-79 [*, concentration in percent; all other concentrations in milligrams per kilogram (mg/kg); <, less than. Statistics calculated from 188 samples] |
|||||
|
Element |
Concentration (mg/kg) for selected percentiles of analyses |
||||
|---|---|---|---|---|---|
|
95 |
75 |
50 (median) |
25 |
5 |
|
|
Aluminum (Al) |
8.07 * |
6.62 * |
5.94 * |
5.28 * |
3.93 * |
|
Barium (Ba) |
1,290 |
758 |
658 |
514 |
280 |
|
Beryllium (Be) |
3.0 |
2.0 |
2.0 |
1.0 |
1.0 |
|
Calcium (Ca) |
5.18 * |
2.76 * |
1.59 * |
1.14 * |
0.67 * |
|
Cerium (Ce) |
143 |
101 |
77 |
60.0 |
38.0 |
|
Chromium (Cr) |
225 |
85.0 |
52.5 |
39.0 |
25.0 |
|
Cobalt (Co) |
20.8 |
12.4 |
9.0 |
7.0 |
4.6 |
|
Copper (Cu) |
44.0 |
28.0 |
20.0 |
15.0 |
10.0 |
|
Hafnium (Hf) |
24.0 |
13.8 |
6.8 |
5.5 |
4.3 |
|
Iron (Fe) |
4.85 * |
3.39 * |
2.76 * |
1.94 * |
1.07 * |
|
Lanthanum (La) |
80.3 |
53.0 |
42.0 |
33.0 |
21.0 |
|
Lead (Pb) |
27.0 |
18.2 |
13.0 |
9.0 |
3.0 |
|
Lithium (Li) |
44.7 |
34.0 |
27.0 |
21.0 |
14.0 |
|
Magnesium (Mg) |
3.72 * |
1.99 * |
1.30 * |
0.73 * |
.50 * |
|
Manganese (Mn) |
910 |
684 |
505 |
374 |
204 |
|
Nickel (Ni) |
55.7 |
31.2 |
19.0 |
12.8 |
8.0 |
|
Potassium (K) |
3.02 * |
1.90 * |
1.53 * |
1.27 * |
0.93 * |
|
Scandium (Sc) |
16.5 |
10.8 |
7.8 |
6.0 |
4.0 |
|
Sodium (Na) |
2.21 * |
1.71 * |
1.21 * |
0.66 * |
0.30 * |
|
Strontium (Sr) |
931 |
490 |
490 |
200 |
116 |
|
Thorium (Th) |
30.4 |
17.7 |
11.9 |
8.5 |
3.4 |
|
Titanium (Ti) |
6,840 |
4,810 |
3,550 |
2,890 |
1,890 |
|
Uranium (U) |
8.03 |
4.96 |
3.78 |
2.73 |
1.74 |
|
Vanadium (V) |
146 |
95.5 |
72.0 |
54.0 |
39.4 |
|
Zinc (Zn) |
122 |
111 |
74.5 |
52.8 |
32.7 |
| Table 11. Sediment-quality assessment values for selected elements, Yellowstone River Basin [HSSR, Hydrogeochemical and Stream Sediment Reconnaissance from the National Uranium Resource Evaluation (NURE); PEL, probable effect level; ERM, effects range median; mg/kg, milligrams per kilogram] | |||||
|
Element |
Number of HSSR samples |
PEL (mg/kg) |
HSSR samples below PEL (percent) |
ERM (mg/kg) |
HSSR samples below ERM (percent) |
|---|---|---|---|---|---|
|
Chromium (Cr) |
12,635 |
90 |
78.5 |
70 |
98.2 |
|
Copper (Cu) |
12,622 |
197 |
99.8 |
270 |
99.8 |
|
Lead (Pb) |
12,622 |
91.3 |
99.8 |
218 |
99.9 |
|
Nickel (Ni) |
12,622 |
36 |
85.7 |
51.6 |
93 |
|
Zinc (Zn) |
12,546 |
315 |
99.7 |
410 |
99.8 |
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