Another fascinating Texas Geology summary

http://texasalmanac.com/topics/environment/geology-texas-0

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cool maps of the pennsylvanian period

This site shows maps of extant formations from the different epochs. The Palo Pinto Mountains are from the Carboniferous Period, also known as Pennsylvanian.

Carboniferous in Texas map

This next map shows the now almost eroded Oachita Mountain range that formed around the same time as the Palo Pinto Mountains did, maybe from the same contintental squeezing during pangea around 300 million years ago. The Oachita Mountains eventually sank with the Ft. Worth basin. West Texas maintained its altitudinal sedementary plains as water drained through the rivers and creeks of the Palo Pinto Mountains to the sea.

 

Image result for ancient pennsylvanian mountains texas

 

At last an explanation

I’ve been searching to understand why the Palo Pinto Mountains stretch southeast to northwest, and why the Brazos flows through them at a cross section, northeast to southwest.

TOPOGRAPHY. The region is one of considerable relief, some of the hills rising to heights of 500 feet above the valley floors. The ruggedness of the surface is produced by a series of escarpments which trend in a northeasterly direction and are formed by the outcropping edges of sandstone and limestone beds that dip at low angles to the northwest. The most prominent of these escarpments, about 200 feet above the adjacent plain, is that formed by the group of limestone beds which caps Kyle Mountain. Northwest of this escarpment the country is very rough and in part is heavily timbered. East of the escarpment is a belt of comparatively open country about 5 miles in width, the surface of which, formed by a limestone bed lower than 54 CONTRIBUTIONS TO ECONOMIC GEOLOGY, 1915, PART II. that which caps Kyle Mountain, is covered only by a growth of mesquite. The eroded edge of this lower limestone bed forms the crest of another escarpment, southeast of which are a series of timbercovered escarpments formed by sandstone strata. The county is crossed from northwest to southeast by Brazos Eiver, which flows in wide intrenched meanders, suggesting that its course was chosen when it flowed on a low-lying and featureless plain, which has since been uplifted and eroded. The present stream valley is comparatively narrow and is bordered by high bluffs. https://pubs.usgs.gov/bul/0621e/report.pdf

After at least an hour of more searching, I finally found a name for these escarpments: Mineral Wells-Newark East Fault System.

Map of the Bend-Arch Fort Worth Basin showing earthquake epicenters reported in ...

http://www.sciencedirect.com/science/article/pii/S0031920116301133

Wikipedia has this to say about it: “Major structural features include the Muenster and Red River Arches to the north, and the Bend and Lampasas Arches along the central part of Province 045. Along the east portion is an area that includes the Eastern Shelf and Concho Arch, collectively known as the Concho Platform. The Mineral Wells fault runs northeast-southwest through Palo Pinto, Parker, Wise, Denton Counties and joins with the Newark East fault system. The fault system bisects the Newark East Field (NE-F) creating a zone of poor production in Barnett Shale gas reservoirs. Several faults that cut basement and lower Paleozoic rocks in the southern part of the province are identified at the Ordovician Ellenburger Group stratigraphic level. These faults and associated structures formed during development of the Llano Uplift and Fort Worth Basin with faulting ending by the early Missourian.[4] 

I’d been wondering if the Llano Uplift that produced the famous Texas Hillcountry and the very ancient Oachita Mountain chain that went from Big Bend to Arkansas had anything to do with it. They are why the rivers flow the general direction they do, and the Fault is what the Brazos crosses through northwest of me. All this specific information comes from oil field research, not geology college sites which focus on general ages and more famous landmarks like the Rockies and Big Bend. This sad profit motivated research reminds me of how many techno-advances come during wartime.

Found this while researching the namesake for Ioni Creek

While George and I took a drive to check out Oaks Crossing, we listened to John Graves’ Goodbye to a River. Turns out Ioni Creek was named for an Indian tribe.

The Red Man liked this section of Texas, now known as Palo Pinto County.  Far back in his day and time it was ideal for his living purposes, it was mountainous and had many waterways that made it topographically ideal for his livelihood.  Wild game was plentiful and here he lived, hunted, played and fought, until banished in the 1860’s.

The six tribes reported to have lived in this section were the Anadarkos, Ioni, Caddo, Waco, Keechi and Tawacionis.  These tribes were united in two separate bands, with each governed by a head chief and each tribe also having its own chief.  Chief of the Ioni tribe was Towysh, of the Caddo tribe was Haddebar.  These tribes were united under Chief Jose Maria, who was also chief of his tribe, the Anadarkos.  Chief of the Keechi tribe was Chachetuck and the chief of the Tawaconis was Ocherash, and these tribes were united under Acaquash, Chief of the Waco tribe.  In the six tribes were 1240 Indians and of this number about 240 were warriors.

In June, 1851. Col. Sam Cooper, assistant Adjutant General of the United States, accompanied by Major Sibby and a small company of dragoons, visited the Indian Village on the Brazos on a tour of inspection.  The record of his trip is a most interesting one.  The party left Ft. Graham on the Brazos in the western hill country, traveling northwesterly.  They passed Comanche Peak in Hood County, crossed the Brazos below Littlefield Bend near Parker-Palo Pinto County line.  Located here was the valley of the Ioni Village.  Fourteen miles father the party reached Ioni Village Bend where they camped for a while.  They crossed the river on the north side of the bend and traveled across the prairie to the northeast of where Palo Pinto now stands.  They crossed the Brazos again below the mouth of Eagle Creek and continued to Loving Creek where they ate.  The Keechi Village was the next stop at Bone Bend.  They crossed the Comanche trail a few miles from here, the trail that led to Red River, to the Washita settlement and used by the Comanche in driving stolen horses and mules from one section of the country to buyers in another section.

Col. Cooper thought the establishment of a military post near the Caddo Village where the trail passed would check this traffic.  A small band of Delawares and Shawnees were camped on the left bank of the Brazos, two miles from Barnard’s trading house.

The Indians in this section were said by many of the old timers and subsequent historians to have been perhaps the most friendly in the state.  Those living in nearby counties were not as friendly as the ones living here.  The Indians remained friendly until around 1859 when a band of Indians on a hunting party were attacked by an officer, Captain Garland and a squad of twenty men.  After the skirmish four Indian men, three Indian women were killed and the rest wounded.  That ended friendly relationships with the whites until the Indians left the county.  This was the beginning of their attacks. http://www.rootsweb.ancestry.com/~txpalopi/oddsnends/1857-1957news/ppmountains.htm

 

Hello to a river

My house is a couple of miles southwest of the watershed border between the Brazos and the Trinity River basins. We are on the Brazos side, and the river itself is only 6 miles southwest of our house. That means that most of the tributary creeks run north from the edge of the Texas hill-country. South of that is the Colorado River basin (east of the Rockies, no relation to the one that formed the Grand Canyon), which is probably more scenic. However the Brazos has its scenic bits too; mostly northwest of here along what’s known as the John Graves Scenic Riverway that flows downstream from the Possum Kingdom dam and the Hwy 16 bridge, through the Palo Pinto “Mountains” 19 miles to the Hwy 4 bridge, which my daughter and I peddle kayaked in one glorious day.

Today I was looking at Trulia properties for sale along the Brazos and found Oaks Crossing road that dead ends on either side of the river, maybe 1/4 of the way between the Hwy 180 and 281 bridges. The highway bridges are pretty far apart, and the land in between is private, so canoe/kayak put in/out places are hard to come by. Apparently this is a public crossing, so maybe I could get picked up there if I put in about 10 miles upstream at Hwy 180. I came across another Brazos River book, Bridges Over the Brazos exerpted by goodreads indicating the crossing was used by pioneers and cattlemen as a shallow crossing spot. If the river is low, one could probably drive across in a high clearance vehicle, but many have gotten stuck trying. I’ll have to check it out.