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#Post#: 119--------------------------------------------------
MEGASEQUENCES
By: Admin Date: February 12, 2017, 8:37 pm
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The meaning of the Great Unconformity and Sauk Megasequence
HTML https://creation.com/great-unconformity-and-sauk-megasequence
by Michael J. Oard
Grand-Canyon
Figure 1. The Great Unconformity of the Grand Canyon (upper
arrow) above another nearly-flat unconformity between
Precambrian sedimentary rocks, dipping downward toward the
right, and the igneous and metamorphic rocks below (lower
arrow).
The Great Unconformity, first defined in the Grand Canyon in
1869, separates the Cambrian Tapeats Sandstone from the
underlying Precambrian rocks (the geological column and
timescale are used for discussion purposes only). There is some
confusion in the Grand Canyon in that there is a second major
unconformity between the Precambrian sedimentary rocks and the
igneous and metamorphic rocks (figure 1). The uniformitarian
origin of the Great Unconformity is supposed to be slow
denudation over about a billion years that resulted in a nearly
flat planation surface. Then after this denudation, a shallow
marine transgression deposited the Tapeats Sandstone, Bright
Angel Shale, and Muav Limestone in a fining upward sequence
called the Tonto Group.
It is now known that the Great Unconformity has a wide extent
over North America, as seen on top of the upper crust. The Great
Unconformity is a distinctive physical boundary between mostly
igneous rocks of the upper crust and a layer of sandstone. It
apparently also occurs on other continents:
There has been confusion on the timing of the formation of the
mountaintop planation surfaces.
“The Great Unconformity is well exposed in the Grand Canyon,
but this geomorphic surface, which records the erosion and
weathering of continental crust followed by sediment
accumulation, can be traced across Laurentia and globally,
including Gondwana, Baltica, Avalonia and Siberia, making it the
most widely recognized and distinctive stratigraphic surface in
the rock record.”1
The Great Unconformity is also considered a unique feature
within the last 900 Ma of uniformitarian time.2 The Tonto Group
in the Grand Canyon is also recognized as covering about half of
North America and is called the Sauk Megasequence,1 the bottom
of six megasequences that supposedly account for sedimentation
over North America. The Sauk sequence is well defined
lithologically on top of the upper crust and locally on
Precambrian sedimentary and metasedimentary rocks. However, the
other five sequences are based on many assumptions, such as
fossil dating and not lithology, and are commonly missing large
sections in North America (see below).
The Great Unconformity in Montana and Wyoming
I have observed the Great Unconformity at several locations in
Wyoming and Montana. Whereas the Great Unconformity is near the
bottom of 1,200 m of flat strata in the Grand Canyon, it occurs
at the tops of some mountain ranges in Wyoming and Montana. For
instance, there are planation surfaces on the granite and gneiss
of the Beartooth Mountains, Wind River Mountains, Bighorn
Mountains, and locally in the northern Teton Mountains (figure
2).
Mount-Moran
Figure 2. The top of Mount Moran, Grand Teton National Park,
Wyoming, US, showing the Great Unconformity with a 15 m
erosional remnant of Flathead Sandstone (arrow).4 The vertical
black rock is a dike of diabase, a basalt-like rock.
However, there has been confusion on the timing of the formation
of the mountaintop planation surfaces, i.e. whether these
planation surfaces represent the Great Unconformity. This is
because there are planation surfaces that formed in the area
after the time of the Great Unconformity. For instance, a
planation surface exists on the westward-dipping sedimentary
rocks on the west side of the Wind River Mountains (figure 3) at
about the same elevation as those on the granite and gneiss. A
planation surface also exists on the top of the southern
Absaroka Mountains. These planing events are much later in
‘geological time’ and so have caused some geologists to believe
that the planing event also included the flat-topped granite and
gneiss mountains of the upper continental crust: “The age and
origin of the high-level erosion surface [in the Wind River
Mountains], the Rocky Mountains and others have been the subject
of much debate.”3
The Absaroka Mountains represent volcanic breccia flows, called
the Absaroka Volcanics, that have piled up about 1,800 m deep
over an area of 23,000 km2 and contain multiple levels of
vertical petrified trees at numerous locations.4 They are dated
Eocene, which is early Cenozoic, within the uniformitarian
geological column.
The flows occurred after the Heart Mountain and South Fork
detachments and filled in the depression left after the gravity
slides.5 After deposition and planing of the Absaroka Mountains,
extensive erosion set in to erase the planation surface in the
northern portion and produce canyons up to about 1,200 m deep.
Problems with the uniformitarian explanation
The uniformitarian scientists claim that the Great Unconformity
represents a long period of continental denudation, well over a
billion years at many locations. This is in the context of
attempting to explain the evolution of biomineralization by
means of the geochemical effects of prolonged continental
weathering and denudation.6 However, erosion does not form
planation surfaces today, except locally when a river floods and
erodes its banks.7 Planation surfaces are being destroyed by
present-day erosion, especially by running water that forms
channels and valleys. Geomorphologist C.H. Crickmay states:
“There is no reason to suppose that any kind of wasting ever
planes an area to flatness: decrepitation always roughens;
rain-wash, even on ground already flat and smooth, tends to
furrow it.”8
After the supposed long formation of the Great Unconformity, the
Sauk Megasequence then was spread over much of North America. It
is believed to represent a continental transgression of the sea
but seems contradictory in that the fining upward sequence is so
widespread over large areas. A rising sea level in such a
transgression would be expected to produce a more chaotic
distribution of sediments with much conglomerate over short
lateral and vertical spatial scales—unlike the Sauk
Megasequence.
A possible diluvial explanation of the Great Unconformity and
Sauk Megasequence?
Gypsum-mountain
Figure 3. Planation surface on Gypsum Mountain, northwest Wind
River Mountains of westcentral Wyoming. The mountain is composed
of carbonate rocks with beds dipping west about 40° to the
right.
I have come to the conclusion that the mountaintop planation
surfaces on the granite and gneiss of some Wyoming and Montana
mountains is really the Great Unconformity that has been exhumed
from under thick sedimentary rocks. The evidence for this is
that thick sedimentary rocks still cover many mountain ranges of
the Rocky Mountains, such as the Owl Creek Range that makes up
the southern boundary of the Bighorn basin. The mountains
apparently did not uplift enough for all the sedimentary rocks
to be eroded off. Moreover, Paleozoic erosional remnants have
been left on top of the planation surfaces, such as Beartooth
Butte on top of the Beartooth Mountains and a 15-m thick remnant
of Flathead Sandstone, equivalent to the Tapeats Sandstone in
Grand Canyon, on top of Mount Moran (arrow in figure 2). The
other mountaintop planation surfaces on the west side of the
Wind River Mountains and the Absaroka Mountains would then
represent planation during Flood runoff.
The Great Unconformity and Sauk Megasequence, plus the later
planation surfaces, can be explained by Flood catastrophic
processes. A possible model for the formation of these features
follows. The early Flood unleashed the mechanism of the Flood,
which I think was caused by impacts.9 The very early Flood
should be the most catastrophic part of the Flood, and with
multiple impacts very strong currents and turbulence would
occur. Such a mechanism would scour the continents down to a
planation surface, even causing the second major unconformity
below Precambrian sedimentary rocks in the Grand Canyon. It
would also greatly erode the surface and pulverize the sediments
into fine particles. Little deposition would occur at this
point, except in protected deep basins that are likely impact
basins.10
With the waning of the early Flood mechanism, currents and
turbulence would decrease and the ‘Great Deposition’ would
occur. This deposition resulted in the thick Paleozoic and
Mesozoic sediments that we observe over much of the continents
today. These sedimentary rocks are little deformed, widespread,
fine-grained, and show little, if any, erosion within and
between the layers, as if all these widespread sediment layers
were deposited in one single uninterrupted sequence. In fact,
such deposition was admitted by three geologists for the early
to middle Paleozoic sedimentary rocks uplifted in the Teton
Mountains of northwest Wyoming:
“The regularity and parallelism of the layers in
well-exposed sections suggest that all these rocks were
deposited in a single uninterrupted sequence.”11
However, the geologists do not believe their eyes and stretch
the deposition of this 600-m thick sequence into 200 Ma because
of their stretched-out timescale. Such great time injected
between the layers makes no sense based on present day erosional
patterns that can erode all the continents to sea level in a few
tens of millions of years. Based on erosion today, which is an
application of the uniformitarian principle, the data do not
support such long time periods subjectively interjected within
the sedimentary rocks.
The Great Unconformity is low down in the Grand Canyon but
located at the tops of mountains in Wyoming and Montana.
Such widespread deposition of many layers, one on top of the
other, with little or no erosion is what we would expect during
the early Flood.12 The first megasequence, the Sauk, is well
defined as it covers about half of North America, but it looks
like the other five megasequences are sketchy with missing
megasequences over large areas of North America.
For instance, the next to the oldest megasequence, the
Tippecanoe (dated as Ordovician and Silurian), is almost
entirely missing from the Grand Canyon area and in Montana and
Wyoming. Moreover, the second-youngest megasequence, the Zuni,
is missing over most of central and eastern North America. Maybe
this was because of erosion. Regardless, further research is
required to understand whether such megasequences are real or
not and what they may mean.
The warping of the Great Unconformity
Once the thick Paleozoic and Mesozoic sedimentary rocks were
deposited in the Rocky Mountains region, great differential
uplift (Psalm 104:8) occurred in the Cenozoic to form the
current high mountains and deep basins filled with thick
sedimentary rocks.13 For instance, the Uinta Mountains of
northeast Utah rose up 12 km relative to the adjacent basins
during the Cenozoic.14 That is why the Great Unconformity is low
down in the Grand Canyon but located at the tops of mountains in
Wyoming and Montana. The thick sedimentary rocks were greatly
eroded from off many of the ranges in the Rocky Mountains and
Colorado Plateau with some of the eroded debris continuing to
fill up the valleys and basins of the Rocky Mountains and being
transported off the continent to form the continental
shelves.15,16 This is the time when the continents were greatly
eroded, forming planation surfaces with tall erosional remnants
during sheet flow erosion, and pediments, water and wind gaps,
deep canyons, and valleys during channelized erosion.13,17
During the channelized erosion, the top several hundred to
possibly 1,000 m of sediments and sedimentary rocks eroded from
the Rocky Mountain basins and valleys and High Plains of the
western United States.
The Flood can indeed explain the big picture geology of the
continents, including the Great Unconformity, the Great
Deposition starting with the Sauk Megasequence over half of
North America, differential vertical tectonics, and the huge
erosion of the continents that resulted in all the unique
geomorphological features.
Related Articles
It’s plain to see
Defining the Flood/post-Flood boundary in sedimentary rocks
The remarkable African Planation Surface
Can the relative timing of radioisotope dates be applied to
biblical geology?
Further Reading
Noah’s long-distance travelers
Large cratonic basins likely of impact origin
References and notes
Peters, S.E. and Gaines, R.R., Formation of the ‘Great
Unconformity’ as a trigger for the Cambrian explosion, Nature
484:363, 2012. Return to text.
Peters and Gaines, ref. 1, p. 366. Return to text.
Steidtmann, J.R., Middleton, L.T. and Shuster, M.W.,
Post-Laramide (Oligocene) uplift in the Wind River Range,
Wyoming, Geology 17:38, 1989. Return to text.
Hergenrather, J., Vail, T., Oard, M. and Bokovoy, D., Your
Guide to Yellowstone and Grand Teton National Parks: A different
Perspective, Master Books, Green Forest, AR, 2013. Return to
text.
Clarey, T.L., South Fork and Heart Mountain faults: examples
of catastrophic, gravity-driven ‘overthrusts’, northwest
Wyoming, USA; in: Horstemeyer, M. (Ed.), Proceedings of the
Seventh International Conference on Creationism, Creation
Science Fellowship, Pittsburgh, PA, 2013. Return to text.
Peters and Gains, ref. 1, pp. 363–366. Return to text.
Crickmay, C.H., The Work of the River: A Critical Study of
the Central Aspects of Geomorphogeny, American Elsevier, New
York, p. 214, 1974. Return to text.
Crickmay, ref. 7, p. 127. Return to text.
Oard, M.J., How many impact craters should there be on the
earth?, J. Creation 23(3):61–69, 2009. Return to text.
Oard, M.J., Large cratonic basins likely of impact origin,
J. Creation 27(3):118–127, 2013;
creation.com/large-cratonic-basins. Return to text.
Love, J.D., Reed, Jr., J.C. and Pierce, K.L., Creation of
the Teton Landscape: A Geological Chronicle of Jackson Hole &
and the Teton Range, Grand Teton Association, Moose, WY, p. 42,
2007. Return to text.
Walker, T., A biblical geological model; in: Walsh, R.E.
(Ed.), Proceedings of the Third International Conference on
Creationism, technical symposium sessions, Creation Science
Fellowship, Pittsburgh, PA, pp. 581–592, 1994. Return to text.
Oard, M.J., Flood by Design: Receding Water Shapes the
Earth’s Surface, Master Books, Green Forest, AR, 2008. Return to
text.
Oard, M.J., The Uinta Mountains and the Flood Part I.
Geology, Creation Research Society Quarterly 49(2):109–121,
2012. Return to text.
Oard, M.J., Surficial continental erosion places the
Flood/post-Flood boundary in the late Cenozoic, J. Creation
27(2):62–70, 2013; creation.com/flood-boundary-erosion. Return
to text.
Oard, M.J., Massive erosion of continents demonstrates Flood
runoff, Creation 35(3):44–47, 2013; creation.com/flood-runoff.
Return to text.
Oard, M.J., Earth’s surface shaped by Genesis Flood runoff,
michael.oards.net. Return to text.
#Post#: 144--------------------------------------------------
Re: MEGASEQUENCES
By: Admin Date: February 27, 2017, 1:41 pm
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The Worldwide Flood - Geologic Evidences - Pt 1 with Dr. Andrew
Snelling - Origins
youtube.com/watch?v=jwGgSNDPhO0
Here are my Notes on the Flood Video called The Worldwide Flood
- Geologic Evidences: youtube.com/watch?v=jwGgSNDPhO0
3'37": Evidence: If there was a Great Flood, the ocean waters
could have flooded the continents, bringing along sand, mud and
ocean creatures.
5'20": Tapeats Sandstone, Redwall Limestone and Coconino
Sandstone belong to 5 megasequences of strata that cover much of
North America.
5'42": Tapeats covers about 2/3 of U.S. and part of western
Canada. It's also found in Israel.
6'24": Redwall having same features and fossils is found in AZ,
TN, PA, England, Himalayas near Nepal,
7'00": Cretacious chalk, over 1,000 ft thick in places, is found
in Ireland, S. England, Europe, Egypt, Turkey, Western Australia
and in the U.S. from NE to TX.
8'40": Coconino, 300 ft thick, has crossbedding diagonal to the
horizontal strata formed from underwater sand dune waves with
the tops washed off.
10'53": Coconino covers from AZ to KS to TX. The sand waves
started at 60 ft high each in water moving 3-5 mph. Coconino was
deposited in a few days. The entire Grand Canyon strata were
deposited in a few months.
12'54": Ayers Rock in central Australia is sandstone with nearly
vertical strata with grains of different sizes, angular and some
delicate, meaning they were deposited rapidly (from 60 miles
away).
15'57": Ayers sandstone is over 18,000 ft thick. It was
deposited within hours by turbidity currents moving up to 70
mph.
20'00": Coconino is over Hermit shale. Shale is hardened mud.
Coconino sand came from Canada
22'00": Navajo sandstone in s. Utah lies over Coconino. Navajo
sand contains zircons and quartz eroded from mountains of PA and
NY.
23'00": Sand waves are direction indicators, indicating that
Flood waters flowed during the Paleozoic over the Americas from
n.e. to s.w. The same direction of flow occurred on the other
continents too.
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