Presentation is loading. Please wait.

Presentation is loading. Please wait.

The Geologic Column Sean D. Pitman, M.D. May 2006

Similar presentations

Presentation on theme: "The Geologic Column Sean D. Pitman, M.D. May 2006"— Presentation transcript:

1 The Geologic Column Sean D. Pitman, M.D. May 2006



4 Features of the Geologic Column Made of layers of sedimentary rock Layers generally very flat/even relative to each other Found generally all over the globe –Some areas have missing layers –Some areas have most if not all the layers Found on mountains such as the Swiss Alps, Mt. Everest, American Rockies, Himalayas, Appalachians, etc... Popularly thought to record millions and even billions of years of Earth’s history



7 An Old Geologic Column?

8 Foot of the Book Cliffs northwest of Grand Junction, CO


10 Layers are flat/even relative to each other Layers often extend over hundreds of thousands of square miles Where is the expected unevenness usually seen with weathering?






16 The Speed of Erosion Rockies currently uplifted at 100-1000 cm/Kyr No change in elevation Erosion rate is matching uplift rate Current uplift thought to have started 70 million years ago (Laramide Orogeny) An erosion rate of 100 cm/Kyr equals 1,000 meters of erosion per million years or an incredible 70,000 meters in 70 million years Total thickness of layers in this region is ~3,500 meters – including the Tertiary layers

17 Ruxton and McDougall (1967) report erosion rates of 8 cm/Kyr near sea level and 52 cm/Kyr at an altitude of 975 m in the Hydrographers Range in Papua 92 cm/Kyr for Guatemala-Mexico Border Mountains Himalayas = 200 cm/Kyr 800 cm/Kyr for Mt. Rainier region 1900 cm/Kyr New Guinea volcano Chugach and St. Elias mountain ranges in southeast Alaska, are currently eroding at "50 to 100 times" the current Rocky Mountain rate - i.e., at about 5 to 10 cm/year or 50,000 to 100,000 meters or erosion per million years Yet, many of these mountain ranges still have very "old" sedimentary layers on their surfaces? Go figure... Ariel Roth:

18 Mt. Everest Thought to be about 50 million years old Himalayan erosion rate ~200cm/kyr Just 100 cm/Kyr of erosion equals ~50,000 vertical meters of erosion in 50 My Still covered by Ordovician limestone - only about halfway down the column! Perhaps the layers used to be much thicker? –Only some 6000 m of sediment once covered Everest –Harutaka Sakai suggest have of Everest slid off 20 Ma –Ordovician exposed for 20 Ma and its still there? Really?

19 The Colorado Plateau Colorado River sediment equals 500,000 tons per day –before Glenn Canyon dam Sandstone = 140 pounds per cubic foot 7.1 million cubic feet of erosion per day from an area of ~200,000 square miles (~5.57 trillion sqft) 2.6 billion cubic feet of erosion per year Colorado Plateau uplifted ~15 million years ago? 38,000 trillion cubic feet of erosion in 15 million years 7,000 vertical feet (2,100 m) eroded in 15 million years Tertiary sediments survived atop the Grand Staircase?

20 ~2000 m Why did ~2000 vertical meters erode in one region, but not in the other? Was there really an additional 2,100 meters of tertiary sediment above Brian Head? Shouldn’t the higher reliefs erode more quickly?

21 Brian Head Oligocene 32 Ma Kaibab Limestone Paleozoic 250 Ma

22 Today’s continents average 0.875 km above sea level Land surface area: 148,647,000 sq km Cubic km above sea level: 130,066,125 km 3 An average of several references suggest that about 13.6 km 3 of solid material are carried by all the rivers of the Earth into the oceans every year –31,000 million metric tons/year Time needed to erode away all land currently above sea level: ~9.5 million years

23 What About Human Impact? “Humans have simultaneously increased the sediment transport by global rivers through soil erosion (by 0.6 - 2.3 billion metric tons per year), yet reduced the flux of sediment reaching the world’s coasts (by 0.3 - 1.4 billion metric tons per year) because of retention within reservoirs.” James P. M. Syvitski, Charles J. Vo¨ro¨smarty, Albert J. Kettner, Pamela Green Impact of Humans on the Flux of Terrestrial Sediment to the Global Coastal Ocean, Science, VOL 308, 15 APRIL 2005

24 C. R. Twidale recognized this problem as far back as a 1976 in the American Journal of Science: “Even if it is accepted that estimates of the contemporary rate of degradation of land surfaces are several orders too high (Dole and Stabler, 1909; Judson and Ritter, 1964; see also Gilluly, 1955; Menard, 1961) to provide an accurate yardstick of erosion in the geological past there has surely been ample time for the very ancient features preserved in the present landscape to have been eradicated several times over... ”

25 “... Yet the silcreted land surface of central Australia has survived perhaps 20 m.y. of weathering and erosion under varied climatic conditions, as has the laterite surface of the northern areas of the continent. The laterite surface of the Gulfs region of South Australia is even more remarkable, for it has persisted through some 200 m.y. of epigene [surface] attack. The forms preserved on the granite residuals of Eyre Peninsula have likewise withstood long periods of exposure and yet remain recognizably the landforms that developed under weathering attack many millions of years ago... The survival of these paleoforms [as Kangaroo Island] is in some degree an embarrassment to all of the commonly accepted models of landscape development.”

26 Dott and Batten (1971) noted: "North America is being denuded at a rate that could level it in a mere 10 million years, or, to put it another way, at the same rate, ten North Americas could have been eroded since middle Cretaceous time 100 m.y. ago."

27 B.W. Sparks (1986) in Geomorphology: "Some of these rates [of erosion] are obviously staggering; the Yellow River could peneplain [flatten out] an area with the average height that of Everest in 10 million years. The student has two courses open to him: to accept long extrapolations of short-term denudation [erosion] figures and doubt the reality of the erosion surfaces, or to accept the erosion surfaces and be skeptical about the validity of long extrapolations of present erosion rates."

28 The “Smooth” Grand Canyon Dome ~2000 m


30 How did Red Butte Survive 5.5 million years?

31 Red Butte, Arizona

32 Beartooth Butte 300-400 million yeas old Same layers: Paleozoic

33 Beartooth Butte, Wyoming

34 Sheep Mountain, WY

35 Eroded Dome of Sheep Mountain


37 Little Sheep Mountain area, Bighorn Basin, WY


39 Pryor Mountains north of Lovell, WY

40 Bighorn River Canyon Between Pryor and Bighorn Mountains, MT

41 10 miles east of Moab, UT

42 25 miles northwest of Twin Falls, ID

43 W E N S

44 Straight shot with few twists or U-shaped turns The Real Grand Canyon


46 Scablands of eastern Washington

47 Deccan Traps, India

48 Thick pile of basalt lava flows (~2,000 m thick) Cover 500,000 km 2 with a volume of >1,000,000 km 3 Thought to have formed about 65 mya over the course of 30,000 years and played a role in the extinction of the dinosaurs Individual flows understood to form very quickly (a few days) because they cover over 100 miles Time between lava flows: 2 to 3 hundred years Not enough time for significant erosion between flows

49 Deccan Traps, India

50 Granite Boulders, Deccan Plateau

51 If Deccan Plateau and Deccan Traps formed some 65 mya what would erosion do to them over this time? Current rates of at least 4 cm/Kyr for granite and16 cm/Kyr for basalt equals 2,600 meters and 10,400 meters of erosion respectively How did the Deccan Plateau (granite), much less the Traps (basalt) survive?

52 Columbia River Basalt Group Northeastern US 163,000 sq Km 300 individual flows extending up to 750 Km from their origin The CRBG is believed to span the Miocene Epoch over a period of 11 million years (from 17 to 6 million years ago via radiometric dating)


54 Average time between flows = 36,000 years –Enough time for 6 to 7 meters (19 to 23 feet) of vertical erosion – yet no evidence? Several examples where two or three different flows within the CRBG mix with each other

55 Erosion rates too high? Some suggest rates <0.5 cm/Kyr for exposed basaltic rocks Real time study by Riebe et al (2001) on erosion rates of the granites in the Sierra Nevada region –Average of 4-5 cm per 1,000 years (Kyr) –Range of between 2.0 cm to 6.1 cm per Kyr –Independent of very different climactic conditions Lasaga and Rye (Yale University) –Basalts from the CRBG erode, long term, “about 4 times as fast as non-basaltic rocks” (Idaho Batholith) Basalt erosion would therefore average 16 to 20 cm/Kyr (6-7 m per 36 Kyr) Several thousand years worth of erosion can occur in one year (episodic erosion - Idaho Batholith, 1997) –(

56 Lincoln Porphyry lava flows of Colorado –Originally thought to be a single unit because of the geographic proximity of the outcrops and the mineralogical and chemical similarities throughout the formation –Revised after radiometric dating placed various layers almost 30 My apart in time –No erosion despite hundreds of thousands of years between layers

57 Tertiary lava flows in the Gunnedah Basin sequence exist between Triassic and Jurassic sediments which are thought to be over 100 million years older. Over a large horizontal scale, these flows grade imperceptibly into lavas which overlie Lower Tertiary sedimentary rock. Consequently, the lava flows that are found between the Triassic and Jurassic are considered Tertiary! Otherwise, geologists would have to acknowledge that everything between Jurassic and Early Tertiary is contemporaneous! - Robert Kingham (1998) Australian Geologic Survey Organization

58 Younger With Time?


60 What is one of the strongest evidences that the Geologic Column is much older than YEC notions of “less than 10,000 years”? “The Grand Canyon lava dams required hundreds of thousands of years to erode – each!”

61 The Baby Grand? Ed Stiles, "Is the Grand Canyon a Geologic Infant?" The University of Arizona News, OPI, July 18, 2002 2000 foot GC lava dams collapsed within 80 minutes! Huge wall of water suddenly released “37 times the flow of the largest flooding of the Mississippi River”

62 Huge amounts of rapidly moving water equal huge amounts of rapid erosion Certain portions of the Grand Canyon, once thought to be up to 5 million years old (Marble Canyon and the Inner Gorge), “may be as young as 600,000 years old” Initial dating of 5 My backed up by K/Ar dating, now thought to be inaccurate in this region due to the lack of complete removal of the argon daughter product at the time of initial formation of the lava dams

63 Mather Gorge and Holtwood Gorge in Pennsylvania Used to be 180 million years old July, 2004: Luke J. Reusser, a geologist at the University of Vermont in Burlington, used measurements of beryllium-10 that builds up in quartz when exposed to cosmic rays to re- date these gorges to just 13,000 years Younger now by 4 orders of magnitude!

64 Monument Valley Over 50 million years of erosion?





69 Ripple Marks?



72 “Priest & Nuns” of Castle Rock SW view of Castle Valley, 10 miles east of Moab, UT

73 Arches National Park 100 million years of erosion in southeastern Utah?






79 More than 2,000 arches within 73,000 acres of southeastern Utah Once buried by almost 1 mile of sediment Local uplift caused cracks to form 100 million years ago Subsequent erosion expanded the cracks to form the fins and arches that we see today

80 Arches National Park, UT


82 Entrada sandstone (Jurassic) Arches Nation Park, UT

83 Landscape Arch, 291 ft.

84 Landscape Arch

85 Erosion rates too high for the layers to still be there, much less thin walled high-relief fins to survive for tens of millions of years Note also that only the surface layers of these fins show any evidence of significant erosion

86 Paraconformities

87 Redwall Limestone Supai Group Muav Limestone 150 million years 30 million years

88 Paraconformity – sediments on sediments (same orientation) no obvious erosion surface (Boggs, p. 456)

89 Redwall

90 Paraconformities Millions of years, no sedimentary layer Where did it go? No evidence of erosion How does solid rock interdigitate over and over again with sediments that come along millions of years later?

91 Top layers of GC region are Permian (250 to 290 my) Next should come the Pennsylvanian (290-320 my) – Not there! 30 my Completely missing? Permian rests direction on the Redwall Limestone (Mississippian; ~325 to 345 my) Red color of the Redwall Limestone result of iron oxide derived from the overlying Supai Assemblage Interesting that many meters of solid rock could be stained so completely and so evenly by iron oxide from overlying sediments

92 Below the Redwall Limestone should come the Devonian, Silurian, and Ordovician layers (totaling more than 150 million years of time), but they too are completely missing except for a few small "lenses" of Devonian Redwall is found resting directly on and interdigitating with the Muav Limestone - which contains many trilobites and other Cambrian fossils

93 Dead Horse Point, Utah Gaps cover 250,000 sq. km

94 N.D. Newell, in the 1984 issue of the Princeton University Press, made a very interesting and revealing comment concerning this paraconformity phenomenon: "A puzzling characteristic of the erathem boundaries and of many other major biostratigraphic boundaries [boundaries between differing fossil assemblages] is the general lack of physical evidence of subaerial exposure. Traces of deep leaching, scour, channeling, and residual gravels tend to be lacking, even where the underlying rocks are cherty limestones (Newell, 1967b). These boundaries are paraconformities that are usually identifiable only by paleontological [fossil] evidence."

95 In an earlier paper Newell noted: "A remarkable aspect of paraconformities in limestone sequences is general lack of evidence of leaching of the undersurface. Residual sods and karst surfaces that might be expected to result from long subaerial exposure are lacking or unrecognized... The origin of paraconformities is uncertain, and I certainly do not have a simple solution to this problem."

96 T. H. Van Andel in Nature, 1981: "I was much influenced early in my career by the recognition that two thin coal seams in Venezuela, separated by a foot of grey clay and deposited in a coastal swamp, were respectively of Lower Palaeocene and Upper Eocene age. The outcrops were excellent but even the closest inspection failed to turn up the precise position of that 15 Myr gap."

97 Empire Mt., Southern Az Older on top of Younger “Nonconformity” Cretaceous Rock capped by “older” Permian Limestone –150 my older Undulating contact zone No evidence of overthrusting –No scraping, gouging, or linear striations –Undulations not smoothed off

98 Angular Unconformity Happened slowly? – or catastrophically?

99 Clastic Dikes


101 Coconino Sand Dunes





106 Coconino sand dunes have an average slope angle of 25° while the average slope angle of modern desert dunes is 30-34° (the “resting” angle of dry sand) Sand dunes formed by underwater currents do not have as high an average slope angle as desert dunes and do not have “avalanche” faces as commonly as deserts dunes do Some crisp avalanche faces are found in the Coconino Sandstone dunes suggesting that at least some exposure to open air occurred, but such exposure may have been intermittent and relatively brief Grain “frosting” occurs both in desert environments as well as during underwater chemical “cementing” during sandstone formation

107 Varves


109 Lambert and Hsü (1979) measured "varves" in Lake Walensee, Switzerland and found up to five laminae deposited during one year From 1811, which was a clear marker point (because a newly built canal discharged into the lake), until 1971, a period of 160 years, they found the number of laminae ranged between 300 and 360 instead of the expected one per year or 160 –Our investigations supported de Geer's first contention that sediment-laden floodwaters could generate turbidity underflows to deposit varves, but threw doubt on his second interpretation that varves or varve-like sediment are necessarily annual. (Lambert and Hsü, p. 454)

110 Julien, Lan and Berthault (1994) experimentally produced laminations by slowly pouring mixtures of sand, limestone and coal into a cylinder of still water Using a variety of materials, they found that laminae formed if there were differences in size and density of the materials and that the thickness of the laminae depended upon differences in grain size and density

111 In many cases where large ice lobes or glaciers sit or float in lakes, there is year round delivery of sediments and turbidite activity occurs almost continually resulting in graded laminae that are not true varves. (Quigley, p. 152) How many varve-like layers form from year to year becomes anyone's guess. Wood (1947) describes peak river inflows after light rain that deposited three varve-like couplets in two weeks. Just as we have seen in many situations, e.g., stalagmite and canyon formation, strata deposition, and fossilization, time is not the essential factor for their development, although evolutionists insist that such things took much time to form. While evolutionary catastrophists admit rapid formation, they almost invariably propose long periods of tedium between catastrophic events. (Ager)

112 Shale Beds



115 Continental Drift


117 2000 years ago Emphesis was a seaport city, now it is 5 miles inland Louisiana coastline is being lost a 25sq. miles per year US spends $500,000,000 to prevent erosion of the east and west coasts Florida spends $8,000,000 per year Past 50 years Washington state has lost over 300 meters of certain of its coastlines Northern and north center regions of California erode at about 30 cm/yr with some areas (Capitola) eroding at up to 1.5 m/yr (Plant and Griggs 1991).

118 Texas is loosing between 0.3 and 15 meters of coastline per year Landmark lighthouse of Cape Hatteras, built 1500 m inland in 1879 has to be moved to avoid collapse into the ocean True all over the world Japan literally spends billions of dollars to prevent erosion

119 What would an average of just 1 cm of coastal erosion/deposition do to the shape of the continents in 200 million years? The change would be two thousand kilometers (1,200 miles)... Enough to erode (or deposit) half way through or onto the United States on all sides! Would the puzzle still fit?

120 Questions?

Download ppt "The Geologic Column Sean D. Pitman, M.D. May 2006"

Similar presentations

Ads by Google