MASTER'S THESIS M-1128
EISENHARD, Robert M. CHARACTERISTICS OF SOME PALEOZOIC CLASTIC SEDIMENTS OF THE CENTRAL APPALACHIANS.
The American University, M.S., 1966 Geology
University Microfilms. Inc., Ann Arbor, Michigan
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. CHARACTERISTICS OF SOME PALEOZOIC CLASTIC SEDIMENTS OF THE CENTRAL APPALACHIANS
by
Robert M. Eisenhard
Submitted to the
Faculty of the College of Arts and Sciences
of The American University
in Partial Fulfillment of
the Requirements for the Degree
of
Master of Science
Signatures of Committee: ' y- ^
ChairmaytT-y^ y ' J - ^ >
Dean of the College Date : (Lf - Date: ^ __/<^y /
1966
The American University Washington, D. C. AMERICAN utiv,?
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 11
CONTENTS
I General Geology, Stratigraphie Section And Area Map ...... 1
II Collection of Samples (including description of Formations) ...... 5
III Preparation of Samples ...... 8
IV Analysis of Samples and Characteristics of Heavy Minerals ...... 9
V Summary and Conclusions ...... 15
VI Appendix ...... 20
Graph I Distribution by Weight Percent of Sieve Fractions ...... 21
Graph II Cumulative Percent of Sieve Fractions by Weight Oriskany, Tuscarora and Conococheague ... 22
Graph III Gumulative Percent of Sieve Fractions by Weight Weverton, Antietam, Martinsburg, Bloomsburg ...... 2.3
Graph IV Heavy Minerals as Percent of Size Fraction ...... 24
Tables I - VII Sieve Fraction Data ...... 25
Table VIII Grain Size and Heavy Mineral Distribu tion ...... 32
References ...... 33
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. I. General Geology
The clastic rock samples for this study were taken from the
northernmost portion of the Appalachian Valley in Virginia. The
Appalachian Valley Province (also known as the Valley and Ridge
Province) is a subdivision of the Appalachian Highlands. To the
southeast of the Appalachian Valley is the Blue Ridge Province and
to the northwest, the Appalachian Plateau.
Surface exposures in the area show folded and thrust faulted
Cambrian, Ordovician, Silurian and Devonian sedimentary rocks which
were deposited in the Appalachian geosyncline. Here, essentially
continuous sedimentation produced an average of 30,000 feet and a
maximum of perhaps 50,000 feet of section. (Butts, 1940, p. 3.)
The folding and faulting in some cases make measurements of the
stratigraphie thicknesses at best somewhat questionable.
The eastern half of the area studied varies from nearly flat
to rolling topography. The formations present here are the Tomstown
dolomite, Waynesboro formation, Elbrook, Conococheague, and
Beckmantown limestones, and the Martinsburg shale. The valley
floor is at an altitude of 700' at Winchester rising westward to
1000 feet at the base of Little North Mountain, rising southwest-
ward to 1400 feet at Harrisonburg and decreasing eastward to 500
feet at the Shenandoah River (Butts, 1940, p. 7). In the
Massanutten Mountain region and in the western half of the area,
the tough resistant Tuscarora quartzite along with the Oriskany
sandstone support long ridges rising 1000 to 1500 feet above the
valley floor. Inside the Tuscarora ridges of the Massanutten
syncline, the Romney shale forms the valley. In the western
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. portion of the area, the Jennings and Romney formations form the
valley floors. On the eastern margin the Cambrian Weverton
formation and Antietam quartzite underlie the eastern ridge.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. GENERALIZED STRATIGRAPHIC SECTION FOR THE APPALACHIAN VALLEY IN NORTHERN VIRGINIA
(after Cloos, Butts, Stose and others)
Formations in CAPITALS are those studied
Catskill formation Juniata formation
Jennings formation MARTINSBURG SHALE
Romney shale Chambersburg limestone % I ORISKANY SANDSTONE St. Paul group Q a > Helderburg limestone o Beekmantown limestone
Rockdale Run formation
Keyser limestone Stonehenge limestone
Tondcway limestone
Wills Creek shale CONOCOCHEAGUE LIMESTONE
BLOOMSBURG FORMATION Elbrook limestone formation
McKenzie formation Waynesboro formation
TUSCARORA QUARTZITE Tomstown dolomite
§ ANTIETAM QUARTZITE Pi Harpers shale Ü WEVERTON FORMATION
Loudoun formation
Catoctin volcanics
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During the summer of 1962, samples were collected in the
Appalachian Valley in northwestern Virginia. Sites were chosen
in Frederick, Clarke, and Shenandoah Counties where typical expo
sures of the desired clastic Paleozoic sediments were to be found.
At all locations, multiple samples of the formations were made
with an effort to collect a representative set of samples based
on grain size, color, mineral content, cementation, induration
and structural position.
Weverton Quartzite, -6wg, Lower Cambrian:
The Weverton quartzite was named by Keith (1892, p. 365;
1893, p. 329; 1894) with a type section at Weverton, Maryland. It
is described by Nickelsen (1956, p. 248) as three quartzite members
with two intermediate phyllite members with thin quartzite inter
beds. It is light gray to dark gray to vitreous bluish-black in
the quartzite members. The upper member is poorly sorted with much
cross bedding while the lower member is the best sorted with only
local small-scale cross bedding. Samples were taken along a .3
mile stretch east from the horseshoe curve at Snickers Gap on Rt. 7.
Approaching this location from the east, the Weverton exposure
begins about 1.4 mile after the first road to Bluemont.
Antietam Quartzite, -fia. Lower Cambrian:
The Antietam quartzite was named by Keith (1893, p. 335) and
Williams and Clark (1893, p. 68). The type section is Antietam
Creek, Maryland. The Antietam consists of light gray to medium
gray and light tan, fine to very fine grained massive quartzite.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Some beds darker and more poorly sorted are described as sericitic
quartzite or silty phyllite by Nickelsen (1956, p. 251). Outcrops
were sampled starting 3.4 miles west of the Bluemont Road on Rt. 7
and continuing down the hill for several hundred feet toward the
Shenandoah River.
Conococheague Limestone,-€c, Upper Cambrian:
The Conococheague limestone was named by Stose (1908, p. 701).
The type section was from Conococheague Creek in Franklin County,
Pennsylvania. Stose originally included the present Conococheague
in the Knox formation and described the distinctive basal sand beds.
The Conococheague consists of medium gray limestone, calcareous
sandstone, dolomite and dolomitic siltstone. Oolites, limestone
pebble conglomerates, and cryptozoon algae are present in this for
mation in many places. The sandy beds in this formation were
sampled approximately 3% miles west of Winchester, on Rt. 50, 1
mile east of the Little North Mountain Gap where the Conococheague
is exposed in a road cut through an orchard.
Martinsburg, Omb, Ordovician:
The Martinsburg shale was named by Geiger & Keith (1891) for a
belt of shale east of Martinsburg, West Virginia. The Martinsburg
consists of nearly black, chippy, fissile shale, medium brown
siltstones and various gray graywackes, with lesser low grade
slates, thin limestones, dolomite, chert, and conglomerates.
Weathering in many cases produces a yellow-brown hue. Samples
were first taken 1.8 mile west of Opequon Creek on Rt. 7 east of
Winchester. Additional samples were taken at exposures in readouts
east of Winchester and south of Winchester on Rt. 522.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Tuscarora, Stc, Silurian:
The Tuscarora was named by Darton in 1896 (Darton and Taff,
1896; Darton, 1896) from Tuscarora Mountain, Pennsylvania. The
Tuscarora is a very fine to medium grained quartzite. The degree
of diagenesis varies so that a few layers are nearly friable and
others massive. All samples, though, had at least some grains that
show typical quartzitic fracture. Much of the Tuscarora is white
to light gray with some grading to medium gray and some to pink.
A minor amount of conglomerate with small quartz pebbles is also
present. Samples of Tuscarora were collected in the Massanutten
area on Rt. 678 as it enters the syncline from the north and at the
Woodstock fire tower.
Bloomsburg, Sb, Silurian:
The Bloomsburg formation was named by White in 1883 (White,
1883, p. 252) for a well developed section in Bloomsburg, Columbia
County, Pennsylvania. The Bloomsburg formation consists of massive
medium red, fine to medium grained sandstone and shale. Butts
(1940, p. 253) includes some green and gray sandstone and shale
layers in the formation. Samples for this study were collected
from the outcrop near the Woodstock fire tower in the Massanutten
area. The outcrop is on the right of the road heading west from
Detrick toward Woodstock about 200' before the crest on which the
tower is located.
Oriskany Sandstone, Do, Lower Devonian:
The Oriskany sandstone was named by Hall (1839) for outcrops
at Oriskany Falls, Oneida County, New York. It consists mainly
of a medium to coarse grained quartz sandstone. It is quite thin
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. in the Massanutten area (estimated by Butts (1940) as being 10
feet thick). Samples were taken from an outcrop along the slope
between the Little Fort camping area and the Woodstock tower.
III. Preparation of Samples
Samples collected at the outcrop locations were returned to
the laboratory for examination. Samples were first cleaned of
extraneous material and washed. A Denver Fire Clay Co. Crusher
was used to crush the samples into grinder size and then they were
put through an H e r Improved Grinder for final preparation. Through
frequent examination, care was taken to avoid overcrushing of the
samples and in most part individual grains appear not to have
suffered much from the grinding.
Once the samples were disaggregated by crushing, size separa
tion was accomplished by sieveing. Standard U. S. Sieve Sizes were
used. Grain sizes resting on the following sieves were collected:
30, 40, 50, 60, 70, 100, 120, 140, 170, 200, 250, 325 and in the
pan under 325. Those collected on the number 30 sieve were in most
cases composite grains and were excluded from further analysis.
The sieved fractions were now weighed to the nearest 1/10 of a
gram. Weight per cent of each fraction to total sample was cal
culated as well as cumulative weight per cent data for each sample.
The heavy minerals were then separated from each fraction of
each sample. To accomplish this, bromoform, CHBr^ (specific
gravity of 2.87 @ 20°C) was used in a series of separatory funnels
with acetone used for a wash. Samples in the separatory funnels
were repeatedly stirred and heavy minerals drawn off until no more
heavy minerals were seen to separate. No. 1, W. and R. Ralston Ltd.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 18.5 Cm. filter papers were used and gave a reasonable fast filtra
tion. In about ten fractions, due to large volume, a Sepor
Separator was used to split the fraction and only a portion of it
was used for heavy mineral separation. In no sample thus split
was the fraction used less than 80 grams. Heavy minerals were
weighed and weight per cent of each fraction calculated.
Heavy minerals were then examined by binocular and pétrographie
microscope for identification and to determine such characteristics
as color, crystal form, roundness, frosting, secondary growths, and
other identifiable characteristics.
IV. Analysis of Samples and Characteristics of Heavy Minerals
1. Distribution of grain sizes is shown in Graph I for all seven
samples studied.
2. The cumulative weight percent of fractions for each sample is
plotted on semi-logarithmic paper as Graph II and III. The
Oriskany sandstone, Tuscarora quartzite, and the Conococheague
make up Graph II and the Weverton formation, Antietam quartzite,
Martinsburg shale and the Bloomsburg formation make up Graph III.
3. Distribution of heavy minerals by size fraction is shown in
Graph IV for all samples.
4. Tables I through VII contain the sieve fraction data.
5. Table VIII contains data relating to grain size distribution
and heavy mineral distribution.
The <100^ 120 size fraction of all samples was examined by
binocular and pétrographie microscope and the larger and smaller
sizes checked for notable differences.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 10
Weverton Quartzite
The heavy mineral assemblage of the Weverton as sampled was
nearly equally divided between opaque and non-opaque minerals and
totalled 17 percent of the rock. Of the non-opaque minerals, 95
percent were a light green waxy, fresh appearing, hackly sericite.
Sericite, therefore, makes up about 8 percent of the quartzite
comparing favorably with the 5-10 percent of Nickelsen (1956).
Zircon and tourmaline composed the remainder of the non-opaque
minerals. Zircon appeared more abundant with few sub-angular and
more sub-rounded, clear, light pink and very pale yellow grains.
Some showed imperfect cleavage. The tourmaline was light pink to
rose pink, with a few clear grains sub-rounded to well rounded.
Small secondary growths similar to those described by Stow (1932)
on Oriskany sandstone tourmaline are present in nearly one quarter
of the grains. These growths are attached at the end of the c-
axis and are fresh and pointed. Most authigenic growths are clear
but some have slight tints of pink or yellow. Some grains, though
rounding has proceeded well along, still show the elongated shape
of the original crystal. Many tourmalines contain numerous inclu
sions. Several elongated watermelon shaped grains of red brown
tourmaline were also observed. Opaque grains are ilmenite, highly
lustrous with a purple sheen, magnetite including a few euhedral
crystals and some black rounded to sub-rounded non-magnetic grains
that may be black tourmaline. Most of the ilmenite and magnetite
grains are angular to sub-angular. In addition, some magnetic
reddish brown flakes, probably an altered magnetite are present.
The larger size grains often contain both quartz and ilmenite
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 11
perhaps a product of crushing the hard quartzite. The first non
opaque heavy minerals appear in the <60 >70 and <70 >100 sieve
fractions. No real difference seems to materialize in the assem
blage as the grain size decreases except that above the 200 sieve
size the grains appear more angular perhaps as a result of frac
turing during preparation of samples. Discounting the composite
grains in the coarse heavy mineral fraction, the percent of heavies
increases with decreasing size with a maximum in the <200>250 size.
Antietam Quartzite
In the Antietam quartzite, opaque and non-opaque heavy miner
als vary in proportion from nearly equal parts, <100 >120, to less
than 5 percent opaque minerals in the <200> 250 sieve size. Total
heavy minerals constitute only about .25 percent in the sample
studied. Sericite and tourmaline are most abundant. Tourmaline
is mostly sub-angular to sub-rounded and clear to cloudy light
pink. Some grains showed authigenic overgrowths. Inclusions are
plentiful with some black ones being small and unusually distinct.
A few violet and brown grains are also present. Zircon, less
abundant than tourmaline, occurs as bright, clear and light pink
grains. Two light blue angular zircon grains with imperfect
cleavage were observed but most of the zircon was sub-angular to
sub-round. A few grains showed euhedral form with rounded edges.
Some pitting and inclusions were in evidence and zoning was observed
in one grain. A few grains of gray apatite and a few of muscovite
were found. Opaque minerals consisted of ilmenite, magnetite, and
a few grains of pyrite. Magnetite in addition to angular fresh
appearing black grains, was present as bright magnetic flakes.
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Rutile, as identified by Bloomer and Werner (1955), was not found
in the studied sample. The larger grain sizes again showed com
posite grains of quartz and ilmenite along with the sericite.
Tourmaline and zircon increased as the grain size decreased and
appeared better rounded with most being sub-rounded to well rounded.
Many showed elongate form and some were euhedral with the edges
worn off.
Conococheague Limestone
The arenaceous beds of the Conococheague limestone showed
nearly complete rounding of grains especially in the larger grain
sizes. A few rounded elongated grains and some sub-rounded grains
were present. Two-thirds of the grains are non-opaque and consist
mainly of a large variety of tourmalines and zircon. Tourmaline
is clear, pale pink, pale yellow, dark brown, reddish brown, gray
green, and blue. Some of the opaque grains appear to be black and
deep purple tourmaline. Inclusions are not plentiful. Zircon is
mainly clear but also occurs as pale pink and yellow, light gray
and one blue grain. Tourmalines show cross fracture and small
secondary growths are fairly common with overgrowths usually at
end of c-axis but several along the side of the grains. Pitting
is obvious on most grains to some degree. Two grains of dark
pink garnet were observed and in the <170 >200 size fraction,
angular ilmenite was present. Rounding was less perfect in the
smaller sizes though some partly angular grains were also pitted
on some surfaces indicating breakage perhaps in sample preparation.
A platy black magnetite was also present. Nicholas (1956) in
studying 80 samples from 22 localities identified fresh unaltered
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hornblende, fluorite, muscovite, rutile, biotite, topaz, andulu-
site, staurolite and possibly kyanite. With the exception of two
grains that may have been staurolite, these minerals were not
identified in the samples studied.
Martinsburg Shale
In the Martinsburg shale, the dark opaque minerals make up
about 20 percent of the heavy minerals while leucoxene and a
chloritic material constitute another 60 percent. The dark miner
als decrease until in the <170 > 200 size fraction they are less
than 5 percent. Sub-angular to sub-rounded grains are most
plentiful although a few highly angular, well rounded, as well
as euhedral grains are present. Zircon is more common than
tourmaline. The most common zircon is a pink variety, with some
worn euhedral grains and some nearly rounded ones. Poor cleavage
and a few grains with multiple inclusions were observed. A few
zircon grains clear, colorless to very light pink and light yellow
are noted. Tourmaline was present in a variety of shades from
clear to pink, dark green, blue-gray to the golden orange variety
of Krynine (1940). Inclusions in tourmaline are prominent as
well as clear overgrowths. A trace of sphene and a blue-green
amphibole is noted. McBride (1962) identifies apatite, biotite,
and muscovite and trace amounts of fluorite, garnet, and pyroxene
from his extensive Martinsburg samples. Johnson (1935) listed
hornblende as a heavy mineral in the Martinsburg.
Tuscarora Quartzite
The heavy minerals of the Tuscarora quartzite contain 80
percent opaque and the remainder non-opaque minerals. A dark
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 14
red-brown magnetic magnetite makes up about 30 percent of the
sample. Leucoxene and minor sericite or chlorite grains with
hematite spots are present. A few angular ilmenite, some limonite,
and a few magnetite grains are noted along with some silt-like
grains with hematite cement. Non-opaque heavy numerals consist
mainly of tourmaline and zircon. Tourmaline is most abundant
and is sub-angular to sub-rounded and varies from colorless, to
light yellow, brown, orange-brown, violet, green, and green-gray.
Many inclusions are present with secondary clear or pale growths
also common. Brown tourmaline shows interesting pale pink over
growths. Overgrowths are again commonly extensions to the c-axis
but also continue along parallel to the c-axis on a few grains.
Zircon is mainly colorless though it is also very pale pink or
yellow. A few zircon grains show long rod-like inclusions. Two
muscovite grains were noted. The smaller size fractions are
slightly more rounded with elongate rounded grains more plentiful.
Folk (1960) and Yeakel (1962) both indicate rutile in trace amounts
and Yeakel (1962) identifies garnet and an amphibole.
Bloomsburg Formation
The Bloomsburg formation in the larger sizes contains many
grains of red-brown hematite nature. Non-opaque grains make up
a very small percentage of the heavy minerals and consist mainly
of tourmaline and zircon. A flaky silvery magnetic grain is pre
sent in large numbers and may be specular hematite. Leucoxene,
ilmenite, and magnetite are present but not abundant. Tourmaline
is usually sub-angular to sub-rounded, light pink and light
yellow with some brown and green. Many inclusions are present;
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 15
pitting and staining is observed. Zircon is clear, mostly sub-
angular with some inclusions and stains. Hoskins (1961) lists
epidote and muscovite as minor heavy minerals.
Oriskany Sandstone
In the Oriskany sandstone, larger size non-opaque heavy
minerals account for 40 percent of the grains, while opaque miner
als comprise 60 percent. The opaque minerals decrease until in
the smaller size fractions, non-opaque minerals increase to nearly
90 percent. Opaque minerals are mainly leucoxene and limonite.
A few bright metallic flakes also are present. Magnetite and
ilmenite are scarce. Zircon and tourmaline along with minor
green flaky chlorite are the most common non-opaque heavy miner
als. Zircon, clear and colorless in elongated and rounded grains,
is most abundant. A few zircon grains are very pale pink and
some are euhedral crystals. Tourmaline, the best rounded of the
grains, with some elongate and some euhedral grains is found in
pink, violet, tan, light brown, dark orange-brown, and yellow.
Overgrowths are common. Some opaque grains may also be tourmaline.
Bubble-like inclusions were observed in the pink tourmaline. A
few grains of sub-rounded light brownish yellow rutile were found.
Stow (1938) in a multi-sample study of the Oriskany identified
very minor amounts of garnet, hypersthene, kyanite, amphibole,
and biotite.
V. Summary and Conclusions
All seven clastic sediments studied show a striking simi
larity and consistency of heavy minerals. From the Early Cambrian
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 16
Weverton to the Early Devonian Oriskany, with changes in sericite,
chlorite, iron minerals and their alternation products, the heavy
mineral assemblage varies only slightly in type and amount.
Zircon -- colorless, pink, yellow and a few blue, and tourmaline --
colorless, rose, pink, yellow, blue, green, and brown, are ubiquitous.
A few minor constituents appear and disappear from formation to
formation. Overgrowths on tourmaline described by Stow (1932) and
by many others occur in six of the seven formations. Krynine
(1940) devised four heavy mineral suites or assemblages. The
heavy minerals of these seven Paleozoic formations fit his second
assemblage or "Cambrian assemblage" with some overlapping into
the third, or metamorphic suite, for sericite and chlorite and
the fourth, or non-descript group, for iron minerals such as
magnetite, ilmenite, leucoxene, hematite and limonite. Minerals
from the first suite, that of strongly metamorphic and igneous
rocks, either exist in very small quantities or not at all in
the formations studied. The inescapable conclusion here is that
from early Cambrian time extending at least into Devonian time,
clastic sediments were derived mainly from existing sedimentary
rocks and possibly from some low grade metamorphic areas. If post-
orogenic geosynclinal sediments containing an igneous and strongly
metamorphosed heavy mineral suite have been present in the
Appalachian geosyncline, each must have been eroded away. If
this were true, large hiatiuses and unconformities should appear
in the Paleozoic section in this area, but they do not. Van
Andel (1959) points out that though the number of heavy mineral
assemblages are theoretically infinite, only a few are usually
found. The common constituents of the usual assemblages are the
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hornblende-epidote, epidote, kyanite-zircon, staurolite-zircon,
garnet-zircon-tourmaline and zircon-tourmaline associations.
Pettijohn (1941; 1957; p. 503, 506, 514, 520, 674, 679) supports
intra-stratal solution as the controlling factor in heavy mineral
assemblages in Paleozoic rocks. Van Andel (1959) argues against
the significance of intra-stratal solution and points out that
the literature compilation of Pettijohn (1941) was made primarily
on published United States literature and deals largely with sedi
ments in platform facies that were derived from cratonic sources.
Van Andel (1959, p. 159) concludes as follows:
"In a stable platform environment, where the
sediments are derived from a cratonic, deeply
weathered source of low relief, mineral assem
blages subjected to considerable reworking are
strongly altered and in general stable, except
in the immediate vicinity of fresh out-crops
of igneous and metamorphic rocks."
It appears that the heavy minerals described in the present study
constitute such a stable assemblage.
The Paleozoic formations studied probably were produced in
the following fashion.
The Weverton started with shallow water deposition of
sediments formed by the erosion of deeply weathered metamorphic
and sedimentary formations. As the highlands rose and/or the
basin deepened, the sorting became more imperfect and cross bedding
more common (Nickelsen, 1956). The basin appears to have under
gone cyclic periods during which the margins underwent erosion
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and the basin received the shale and clays which made possible
the phyllitic interbeds of the Weverton and the Harpers formation.
Feldspathic quartzite and quartz sandstone as found in
the Antietam quartzite spread across the basin as uplift and ero
sion bared an older quartzite and a source of feldspars. The
area then proceeded through a long period of quiescence.
The Conococheague formation with arenaceous beds near
the top and bottom, thinning and becoming discontinuous in the
east, shows minor uplift of a source in the northwest (Nickelsen,
1956).
McBride (1962) attributes the flysch-type Martinsburg
shale and graywackes to turbidity currents in a deep narrow trench.
A rising source area probably exposed earlier Martinsburg shales
and other sediments back through the Cambro-Ordovician carbonates,
un-metamorphosed Harpers, the Cambrian quartzites, and granitic
and metamorphic basement.
The Tuscarora indicates a more shallow basin receiving
sediments from older sedimentary rocks being worked and reworked
as beach sands during a period of low source relief.
The erosion cycle continued in this manner until meta
morphic rocks lay exposed to allow for the development of the red
soil which formed the Bloomsburg as a brackish water deposit
(Hoskins, 1961).
Following a long period of limestone and shale deposi
tion, uplift again caused erosion of older quartzites and sandstones
which through reworking and deposition produced the Oriskany sand
stone .
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 19
Heavy mineral analysis are known to be useful in determining
the provenance of sediments. In the present study, the analysis
of such heavy mineral suites shows clearly the times at which
earlier sediments have been exposed to erosion and reworked into
later sedimentary deposits. Information of this sort from many
areas may perhaps eventually provide a clearer picture of Paleozoic
deformation in the Appalachian geosyncline.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 20
VI AFPIT.HI/:
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. GRAPH I
DISTRIBUTION BY WEIGHT PERCENT OF SIEVE FRACTIONS Sieve Sizes From Left of Each Graph > 4 0 <140 > 5 0 <50 > 60 <60 > 7 0 <70 > 1 0 0 <100>120 < 120>|140 <140>;170 < 1 7 0 > i2 0 0 _ 40 40 <200> 250 < 250> 325 <325
30 30
. 20
10 10
TtItI T T I l î r I WEVERTON ANTIETAM CONOCOCHEAGUE MARTINSBURG TUSCARORA BLOOMSBURG ORISKANY 22 ipu; ni|j oi 01 DllUlIÜJBÏJO'
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Reproduced with permission of the copyright owner. Further reproduction prohibited without permission 23 xpuj oqj OÎ 01
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Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. GRAPH IV
HEAVY MINERALS AS PERCENT OF SIZE FRACTIONS Sieve Sizes From 30 Left of Each Graph >40 <40 > 50 N 1-) < 5 0 > 60 < 60> 70 < 7 0 > 100 <100> 120 <120> 140 <140 >170 <170> 200 <200> 250 <250> 325 <325 : ------I s
c/> s M
10
I tI . Ft T t II I left scale 1 111right1 scale right scale right scale right scale leftI scale left scale WEVERTON ANTIETAM CONOCOCHEAGUE MARTINSBURG TUSCARORA BLOOMSBURG ORISKANY 25
TABLE I
SAMPLE # 1 WEVERTON
F r a c t i o n W t. o f % of Cum. H e a v y % H e a v y Sieve Fraction Sample % Minerals Minerals Size (grams) (grams) in Fract:
> 4 0 370.2 34.4 34.4 85.94 23.21
<50 >60 66.6 6.2 57.9 8.50 12.76
<60 >70 69.4 6.5 64.4 10.50 15.12
< 7 0 >100 96.5 9.0 73.4 16.90 17.51
<100 >120 43.0 4.0 77.4 8.11 18.86
<120 7140 22.3 2.1 79.5 4.20 18.83
<140 >170 34.0 3.2 82.7 6.80 20.00
<170 >200 26.2 2.4 85.1 4.90 18.70
<200 >250 44.5 4.1 89.2 12.20 27.41
<250 >325 87.4 8.1 97.3 6.50 7.43
< 3 2 5 29.0 2.7 100.0 .50 1.72
Heavy Minerals = 17.25% of sample
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TABLE I I
SAMPLE #2 ANTIETAM QUARTZITE
Fraction Wt. of % of Cum. Heavy % Heavy Sieve Fraction Sample % Minerals Minerals Size (grams) (grams) in Fract
> 4 0 351.2 18.9 18.9 .6 .17
< 4 0 >50 396.7 21.3 40.2 .8 .20
< 5 0 >60 38.0 2.0 42.2 .1 .26
<60 >70 122.3 6.6 48.8 .5 .40
< 7 0 >100 398.2 21.4 70.2 1.4 .35
<.100 >120 48.0 2.6 72.8 .1 .20
<120 >140 13.8 0.7 73.5 .2 1.44
< 1 4 0 >170 233.2 12.5 86.0 .4 .17
< 170 >200 118.0 6.3 92.3 .1 .08
< 2 0 0 >250 72.0 3.9 96.2 .1 .13
< 2 5 0 >325 59.7 3.2 99.4 .2 .33
< 3 2 5 12.1 .7 100.1 Trace 0
Heavy Minerals = .2415% of sample
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TABLE I I I
SAMPLE # 3 CONOCOCHEAGUE
Fraction W t . of 7o of Cum. Heavy % Heavy Sieve Fraction Sample % Minerals Minerals Size (grams) (grams) in Fract:
> 4 0 314.2 32.0 32.0 T 0
< 4 0 >50 194.2 19.8 51.8 .01 .00
< 50 >60 71.0 7.2 59.0 .01 .01
< 60 >70 85.0 8.7 67.7 .03 .03
< 70 >100 112.5 11.5 79.2 .11 .09
<100 >120 37.0 3.8 83.0 .10 .27
< 120 >140 17.9 1.8 84.8 .05 .27
< 1 4 0 7170 27.3 2.8 87.6 .10 .36
< 170 >200 21.4 2.2 89.8 .09 .42
< 2 0 0 >250 31.0 3.2 93.0 .17 .54
< 2 5 0 >325 31.8 3.2 96.2 .80 2.51
<3 2 5 37.8 3.9 100.1 T 0
Heavy Minerals = .14% of sample
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TABLE IV
SAMPLE # 4 MARTINSBURG SHALE
Fraction Wt. of % of Cum. Heavy 7o H e a v y Sieve Fraction Sample % Minerals Minerals Sive (grams) (grams) in Fract:
> 4 0 227.8 23.6 23.6 .04 .17
< 4 0 > 5 0 192.8 20.0 43.6 .21 .11
< 5 0 >60 50.3 5.2 48.8 .02 .40
< 6 0 >70 76.8 8.0 56.8 .09 .10
< 7 0 >100 153.8 16.0 72.8 .10 .06
< 100 >120 38.0 3.9 76.7 .11 .28
< 1 2 0 >140 14.5 1.5 78.2 .02 .13
< 1 4 0 >170 55.0 5.7 83.9 .07 .12
< 1 7 0 >200 10.0 1.0 84.9 .03 .30
< 2 0 0 >250 72.0 7.5 92.4 1.30 1.80
< 2 5 0 >325 54.4 5.6 98.0 .20 .36
< 3 2 5 18.3 1.9 99.9 .01 00
Heavy Minerals = .23% of sample
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TABLE V
SAMPLE #5 TUSCARORA QUARTZITE
F r a c t i o n W t. o f % of Cum. Heavy % H e a v y Sieve Fraction Sample % Minerals Minerals Size (grams) (grams) in Fract
■=^40 146.9 42.5 42.5 .05 .03
< 4 0 5 0 69.6 20.1 62.6 .05 .07
< 50 >60 25.3 7.3 69.9 .05 .19
< 6 0 >70 24.1 7.0 76.9 .08 .33
< 70 >100 28.7 8.3 85.2 .10 .34
< 1 0 0 >120 11.0 3.2 88.4 .05 .45
< 1 2 0 >140 5.3 1.5 89.9 .04 .75
< 140 >170 8.0 2.3 92.2 .08 1.00
< 1 7 0 >200 3.5 1.0 93.2 .05 1.42
< 2 0 0 >250 7.1 2.1 95.3 .05 .70
< 2 5 0 >325 6.7 1.9 97.2 .12 1.79
< 325 9.3 2.7 99.9 .28 3.01
Heavy Minerals = .28% of sample
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TABLE V I
SAMPLE # 6 BLOOMSBURG
Fraction Wt. of % of Cum. Heavy % Heavy Sieve Fraction Sample % Minerals Minerals Size (grams) (grams) in Fract
^ 4 0 335.5 21.0 21.0 14.6 4.36
< 4 0 5 0 171.3 10.7 31.7 7.7 4.49
< 50 >60 74.6 4.7 36.4 3.0 4.02
< 6 0 >7 0 98.7 6.2 42.6 4.1 4.15
< 70 >100 382.9 24.0 66.6 9.2 2.29
<100 >120 13.6 0.9 67.5 3.7 27.20
< 1 2 0 >140 33.8 2.1 69.6 1.2 3.55
< 1 4 0 >170 90.3 5.7 75.3 13.6 15.06
< 1 7 0 >200 95.9 6.0 81.3 6.4 6.67
< 2 0 0 >250 62.4 3.9 85.2 2.8 4.48
< 2 5 0 >325 163.2 10.2 95.4 T 0
< 3 2 5 74.0 4.6 100.0 T 0
Heavy Minerals = 4.15% of sample
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TABLE V I I
SAMPLE # 7 ORISKANY SANDSTONE
Fraction Wt. of % of Cum. Heavy % Heavy Sieve Fraction Sample % Minerals MineraIs Size (grams) (grams) in Fract
> 4 0 1036.1 29.6 29.6 .5 .05
<40 >50 858.6 24.5 54.1 .5 .06
< 5 0 >60 227.7 6.5 60.6 .2 .08
< 6 0 >70 325.4 9.3 69.9 1.2 .37
< 7 0 >100 420.1 12.0 81.9 11.2 2.66
<100 >120 94.2 2.7 84.6 3.3 3.50
<120 >140 86.0 2.5 87.1 3.0 3.49
<1 4 0 >170 111.7 3.2 90.3 4.7 4.21
< 1 7 0 >200 60.7 1.7 92.0 8.6 14.16
<200 >250 23.3 .7 92.7 .5 2.15
<250 >325 128.5 3.7 96.4 3.7 2.88
< 3 2 5 133.7 3.8 100.2 .3 .22
Heavy Minerals = 1.075% of sample
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GRAIN SIZE AND HEAVY MINERAL DISTRIBUTION
Table VIII
Relative Abundance of Relative Amount of Heavy Grains By Sieve Size Minerals By Sieve Size 2nd 3rd 2nd 3rd Formation Largest Largest Largest Largest Largest Largest
WEVERTON >40 <40 > 50 <70 >100 <2007250 >40 <1407170
ANTIETAM <70>100 <40> 50 >40 <120)140 <60> 70 <707100
CONOCOCHEAGUE >40 <40 > 50 <70>100 <2507325 <2007250 <1707200
MARTINSBURG >40 <40 > 50
TUSCARORA >40 <40 >50 <70>100 <2507325 <170)200 <1407170
BLOOMSBURG 70 100 >40 C250>325 <100)120 <140)170 <1707200
ORISKANY >40 <40 > 50 <70>100 <1707200 <1407170 <1007120 <120)140
andard Sieves Openings in mm.
40 .420
50 .297
60 .250
70 .210
100 .149
120 .125
140 .105
170 .088
200 .074
250 .062
325 .044
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REFERENCES
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References
Andel, T. H. van 1959, Reflections on the Interpretation of Heavy Mineral Analysis, Journal Sed. Petrology, V. 29, No. 2, pp. 153-163. Bloomer, R. 0., and Werner, H. J. 1955, Geology of the Blue Ridge Region in Central Virginia, Geo. Soc. American Bull., V. 66, No. 5, pp. 579-606. Butts, C. 1940, Geology of the Appalachian Valley in Virginia, Virginia Geol. Survey Bull, V. 52. Darton, N. H. 1896, Franklin Folio, West Virginia - Virginia, U. S. Geol. Survey Geol. Atlas, Folio 32, 6 p. Darton, N. H., and Taff, J.A. 1896, Piedmont Folio, West Virginia - Maryland, U. S. Geol. Survey Geol. Atlas, Folio 28, 6 p. Folk, R. L. 1960, Petrology and Origin of the Tuscarora, Rose Hill, and Keefer Formations, Lower and Middle Silurian of Eastern West Virginia, Jour. Sed. Petrology, V. 30, No. 1, pp. 1-58. Geiger, H. R., and Keith, A.1891, The Structure of the Blue Ridge Near Harpers Ferry, Maryland - West Virginia, Geo. Soc. American Bull., V. 2, p. 161. Hall, J. 1839, Third Annual Report of the Fourth Geological District of the State of New York, New York Geol. Survey 3rd Ann. Rept., pp. 308-309. Hoskins, D. M. 1961, Stratigraphy and Paleontology of the Bloomsburg Formation of Pennsylvania and Adjacent States, Pa. Geol. Survey, Bull. G 36, 124 p. Johnson, J. H. 1935, Heavy Minerals From Some Paleozoic Formations (abstract). Va. Acad. Sci. Proc. 1934-35, p. 68. Keith, A. 1892, The Geologic Structure of the Blue Ridge in Maryland and Virginia, Am. Geologist, V. 10, pp. 362-368. 1893, Geology of the Catoctin Belt, U. S. Geol. Survey, 14th Ann. Report, Pt. II, pp. 285-395. 1894, Harpers Ferry Folio, U. S. Geol. Survey Seol. Atlas, Folio 10. Krynine, P. D. 1940, Paleozoic Heavy Minerals From Central Pennsylvania and Their Relationship to Appalachian Structure, Proc. Pa. Acad. Sci., V. XIV, pp. 60-64. McBride, E. F. 1962, Flysch and Associated Beds of the Martinsburg Formation (Ordovician), Central Appalachians, Jour. Sed. Petrology, V. 32, No. 1, pp. 39-91. Nicholas, R. L. 1956, Petrology of the Arenaceous Beds in the Conococheague Formation (late Cambrian) in the Northern Appalachian Valley of Virginia, Jour. Sed. Petrology, V. 26, No. 1, pp. 3-14. Nickelsen, R. P. 1956, Geology of the Blue Ridge Near Harpers Ferry, West Virginia, Geo, Soc. American Bull., V. 67, pp. 239-269. Pettijohn, F. J. 1941, Persistence of Heavy Minerals and Geologic Age, Jour. Geol., V. 49, pp. 610-625. ______1957, Sedimentary Rocks, 2nd Ed., Harper & Brothers, New York, 718 p.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 35
Stose, G. W. 1908, The Cambro-Ordovician Limestones of the Appalachian Valley in Southern Pennsylvania, Jour. Geology, V. 16, p. 701. Stow, M. H. 1932, Authigenic Tourmaline in the Oriskany Sandstone, Am. Mineralogist, V. 17, No. 4, pp. 150-152. ______1938, Conditions of Sedimentation And Sources of the Oriskany Sandstone as Indicated by Petrology, Amer. Assoc. Petroleum Geologists Bull., V. 22, No. 5, pp. 541-564. White, I. C. 1883, The Geology of the Susquehanna River Region in the Six Counties of Wyoming, Lackawanna, Luzerne, Columbia, Montour, and Northumberland, Pa., 2nd Geol. Survey Rept. of Progress G 7, 437 p. Williams, G. H., and Clark, W. B. 1893, Maryland, Its Resources, Industries and Institutions: Baltimore. Yeakel, L. S. Jr. 1962, Tuscarora, Juniata, and Bald Eagle Paleocurrents and Paleogeography in the Central Appalachians, Geo. Soc. American Bull., V. 73, pp. 1515-1540.
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