Front Range
From Wikipedia, the free encyclopedia
| Front Range | |
| Mountain Range | |
 Grays Peak on left with Torreys Peak on right
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| Country | United States |
|---|---|
| State | Colorado |
| Part of | Rocky Mountains |
| Highest point | Grays Peak |
| - elevation | 14,278 ft (4,352 m) |
| - coordinates | |
 The Front Range is shown highlighted on a map of the western United States
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The Front Range is a mountain range of the Rocky Mountains of North America that is located in the north-central portion of the U.S. State of Colorado. The Front Range is so named because, moving west along the 40th parallel north across the Great Plains of North America, it is the first mountain range encountered.
The name "Front Range" is also applied to the Front Range Urban Corridor, the populated region of Colorado and Wyoming just east of the mountain range and extending from Pueblo, Colorado, north to Cheyenne, Wyoming. This urban corridor is made possible by the weather-moderating effect of the Front Range mountains, which help block prevailing storms.
This setting provides both scenery as the Front Range towers over Denver and Boulder and an outdoors hotspot for the people living there who take part in mountain biking, hiking, camping, skiing, and snowboarding during winter. However, millions of years ago the present-day Front Range was home to ancient mountain ranges, deserts, beaches, and even oceans.[1] The evidence for these vastly different landscapes lies in the very rocks the people of Colorado live on. Clues from these rocks have given geologists the necessary tools in unlocking the Front Range’s past.
Contents |
[edit] Pike’s Peak Granite
About 1 billion years ago, the earth was producing mass amounts of molten rock that would one day amalgamate, drift together and combine, to ultimately form the continents we live on today. In the Colorado region, this molten rock spewed and cooled, forming what we now know as the Precambrian Pike’s Peak Granite. Over the next 500 million years, little is known about changes in the sedimentation (sediment deposition) after the granite was produced. However, at about 500 – 300 million years ago, the region began to sink and sediments began to deposit in the newly formed accommodation space. Eroded granite produced sand particles that began to form strata, layers of sediment, in the sinking basin. Sedimentation would continue to take place until about 300 million years ago.[1]
[edit] Fountain formation
Around 300 million years ago, the sinking suddenly reversed, and the sediment-covered granite began to uplift, giving rise to the infamous Ancestral Rocky Mountains. Over the next 150 million years, during uplift the mountains would continue to erode and cover themselves in their own sediment. Wind, gravity, rainwater, snow, and ice-melt supplied rivers that ultimately carved through the granite mountains and eventually led to their end. The sediment from these once gigantic mountains lies in the Fountain Formation today. Red Rocks Amphitheater outside of Denver, Colorado, is actually set into the Fountain Formation.[1]
[edit] Lyons Sandstone
At 280 million years ago, sea levels were low and present-day Colorado was part of the super-continent Pangaea. Sand deserts covered most of the area spreading as dunes seen in the rock record, known today as the Lyons Sandstone. These dunes appear to be cross-bedded and show various fossil footprints and leaf imprints in many of the strata making up the section.[1]
[edit] Lykins Formation
30 million years later, the sediment deposition was still taking place with the introduction of the Lykins Formation. This formation can be best attributed to its wavy layers of muddy limestone and signs of stromatolites that thrived in a smelly tidal flat at present-day Colorado. 250 million years ago, the Ancestral Rockies were burying themselves while the shoreline was present during the break-up of Pangaea. 1This formation began right after Earth’s largest extinction 251 million years ago at the Permian-Triassic Boundary. Ninety percent of the planet’s marine life was destroyed and a great deal on land as well.[1]
[edit] Morrison Formation
After 100 years of deposition, a new environment brought rise to a new formation, the sandstone Morrison Formation. The Morrison Formation contains some of the best fossils of the Late Jurassic. It is especially known for its sauropod tracks and sauropod bones among other dinosaur fossils. As identified by the fossil record, the environment was filled with various types of vegetation such as ferns and zamites.[1] While this time period boast many times of plants, grass and had not yet evolved. [1]
[edit] Dakota Sandstone
The Dakota Sandstone, which was deposited 100 million years ago towards Colorado’s eastern coast, shows evidence of ferns, and dinosaur tracks. Sheets of ripple marks can be seen on some of the strata, confirming the shallow-sea environment.[1]
[edit] Pierre Shale
Over the next 30 million years, the region was finally taken over the by a deep sea, the Cretaceous Western Interior Seaway, and deposited mass amounts of shale over the area known as the Pierre Shale. Both the thick section of shale and the marine life fossils found (ammonites and marine reptile teeth). Colorado eventually drained from being at the bottom of an ocean to land again, giving yield to another fossiliferous rock layer, the Denver Formation. At about 68 million years ago, the Front Range began to rise again due to the Laramide Orogeny in the west.[1]
[edit] Denver Formation
The Denver Formation contained fossils and bones from dinosaurs like Tyrannosaurus Rex and Triceratops. While the forests of vegetation, dinosaurs, and other organisms thrived, their reign would come to an end at the K-T Boundary. In an instant, millions of species are obliterated from a meteor impact in Mexico’s Yucatan Peninsula. While this extinction lead to the dinosaurs’ and other organisms’ demise, some life did prevail to repopulate the earth as it recovered from this tremendous disaster. The uplifted Front Range continued to constantly erode and, by 40 million years ago, the range was once again buried in its own rubble.[1]
[edit] Castle Rock Conglomerate
Suddenly, 37 million years ago, a great volcanic eruption took place in the Collegiate Range and covered the landscape in molten hot ash that instantly torched and consumed everything across the landscape. An entire lush environment was capped in a matter of minutes with 20 feet of extremely resistant rock, rhyolite. However, as seen before, life rebounds, and after a few million years mass floods cut through the rhyolite and eroded much of it as plants and animals began to recolonize the landscape. The mass flooding and erosion of the volcanic rock gave way to the Castle Rock Conglomerate that can be found in the Front Range.[1]
[edit] Quaternary Deposits
Eventually, at about 10 million years ago, the Front Range began to rise up again and the resistant granite in the heart of the mountains thrust upwards and stood tall, while the weaker sediments deposited above it eroded away. As the Front Range rose, streams and recent (16,000 years ago) glaciations during the Quaternary age literally unburied the range by cutting through the weaker sediment and giving rise to the granitic peaks present today.[1] This was the last step in forming the present-day geologic sequence and history of today’s Front Range. [1]
[edit] Prominent peaks
The Front Range includes the highest peaks along the eastern edge of the Rockies. The highest mountain peak in the Front Range is Grays Peak. Other notable mountains include Torreys Peak, Mount Evans, Longs Peak, Pikes Peak, and Mount Bierstadt.
| Rank | Mountain Peak | Subrange | Elevation | Prominence | Isolation |
|---|---|---|---|---|---|
| 1 | Grays Peak[2] NGS | Front Range | 14,278 feet 4352 m |
2,770 feet 844 m |
25.0 miles 40.3 km |
| 2 | Mount Evans NGS | Front Range | 14,265 feet 4348 m |
2,769 feet 844 m |
9.8 miles 15.8 km |
| 3 | Longs Peak NGS | Front Range | 14,259 feet 4346 m |
2,940 feet 896 m |
43.6 miles 70.2 km |
| 4 | Pikes Peak NGS | Pikes Peak Massif | 14,115 feet 4302 m |
5,530 feet 1686 m |
60.8 miles 97.8 km |
| 5 | Mount Silverheels NGS PB | Front Range | 13,829 feet 4215 m |
2,283 feet 696 m |
5.5 miles 8.8 km |
| 6 | Bald Mountain[3] PB | Front Range | 13,690 feet 4173 m |
2,099 feet 640 m |
7.5 miles 12.1 km |
| 7 | Bard Peak[3] PB | Front Range | 13,647 feet 4159 m |
1,701 feet 518 m |
5.4 miles 8.7 km |
| 8 | Hagues Peak NGS PB | Mummy Range | 13,573 feet 4137 m |
2,420 feet 738 m |
15.9 miles 25.6 km |
| 9 | North Arapaho Peak[3] PB | Indian Peaks PB | 13,508 feet 4117 m |
1,665 feet 507 m |
15.4 miles 24.8 km |
| 10 | Parry Peak[3] | Front Range | 13,397 feet 4083 m |
1,731 feet 528 m |
9.5 miles 15.2 km |
| 11 | Mount Richthofen[3] PB | Front Range | 12,945 feet 3946 m |
2,680 feet 817 m |
9.7 miles 15.5 km |
| 12 | Specimen Mountain[3] PB | Front Range | 12,494 feet 3808 m |
1,731 feet 528 m |
4.9 miles 7.8 km |
| 13 | Bison Peak NGS PB | Tarryall Mountains PB | 12,432 feet 3789 m |
2,451 feet 747 m |
19.1 miles 30.8 km |
| 14 | Waugh Mountain[3] PB | South Park Hills PB | 11,716 feet 3571 m |
2,330 feet 710 m |
20.0 miles 32.2 km |
| 15 | Black Mountain NGS PB | South Park Hills PB | 11,649 feet 3551 m |
2,234 feet 681 m |
8.0 miles 12.9 km |
| 16 | Williams Peak NGS PB | South Williams Fork Mountains PB | 11,620 feet 3542 m |
2,049 feet 625 m |
10.8 miles 17.4 km |
| 17 | Puma Peak[3] PB | South Park Hills PB | 11,575 feet 3528 m |
2,260 feet 689 m |
7.4 miles 12.0 km |
| 18 | Thirtynine Mile Mountain[3] PB | South Park Hills PB | 11,553 feet 3521 m |
2,088 feet 636 m |
10.6 miles 17.1 km |
| 19 | Twin Sisters Peaks[3] PB | Front Range | 11,433 feet 3485 m |
2,328 feet 710 m |
4.4 miles 7.0 km |
| 20 | Green Mountain NGS PB | Kenosha Mountains PB | 10,427 feet 3178 m |
1,859 feet 567 m |
4.2 miles 6.7 km |
[edit] See also
- Eldorado Canyon State Park
- Flatirons
- Front Range Urban Corridor
- Garden of the Gods
- Geography of Colorado
- Mountain peaks of Colorado
- Mountain ranges of Colorado
- Mummy Range
- Never Summer Mountains
- Palmer Divide
- Pikes Peak Massif
- Red Rocks Park
- Roxborough State Park
- Southern Rocky Mountains
- State of Colorado
[edit] References
- ^ a b c d e f g h i j k l m Johnson, Kirk R. et. al. (2006). Ancient Denvers. Fulcrum Publishing.
- ^ The summit of Grays Peak is the highest point on the Continental Divide of North America.
- ^ a b c d e f g h i j The elevation of this summit has been converted from the National Geodetic Vertical Datum of 1929 (NGVD 29) to the North American Vertical Datum of 1988 (NAVD 88). National Geodetic Survey
