Search results
Results from the WOW.Com Content Network
Shaded relief map of the Llano Estacado. Texas contains a wide variety of geologic settings. The state's stratigraphy has been largely influenced by marine transgressive-regressive cycles during the Phanerozoic, with a lesser but still significant contribution from late Cenozoic tectonic activity, as well as the remnants of a Paleozoic mountain range.
Cretaceous Formations of the Dallas-Fort Worth Metroplex Geologic map and the labeled geologic formations that lie directly beneath the surface in Dallas County Cretaceous formations of Texas Where the DFW Metroplex was located during the last super continent known as Pangea Placement of Tectonic Plates and DFW location around ≈94 million years ago The Cretaceous rocks in the DFW Metroplex ...
In the Permian geologic period, North-Central Texas was a part of the western coastal zone of equatorial Pangea, a super-continental land mass. [1] Nearby uplifts and mountainous regions, such as the Muenster Arch and Red River Uplift, the Wichita, Arbuckle, and Ouachita mountains developed by the end of the Pennsylvanian, [2] providing elevated topography to the north and east during the Permian.
The rich alluvial soil along the creek was noted by surveyor Elias R. Wightman who was one of the Old Three Hundred. His report attracted Anglo-American settlers in the 1820s. Typically, Stephen F. Austin's colonists burned the canebrake to help enrich the soil. Sugar production became so successful that soon large homes were built so that one ...
The Edwards Plateau is a geographic region forming the crossroads of Central, South and West Texas, United States.It is named in honor of Haden Edwards. [2] It is bounded by the Balcones Fault to the south and east; the Llano Uplift and the Llano Estacado to the north; and the Pecos River and Chihuahuan Desert to the west. [3]
Overlooking the variability of soils seriously reduced the value of the maps which showed the location of the soils. Furthermore, early emphasis on genetic soil profiles was so great as to suggest that material lacking a genetic profile, such as recent alluvium, was not soil. A sharp distinction was drawn between rock weathering and soil formation.
The present consensus is that "alluvium" refers to loose sediments of all types deposited by running water in floodplains or in alluvial fans or related landforms. [1] [7] [8] However, the meaning of the term has varied considerably since it was first defined in the French dictionary of Antoine Furetière, posthumously published in 1690.
They are closely related to sandstones in origin, and exhibit many of the same types of sedimentary structures, such as tabular and trough cross-bedding and graded bedding. [ 1 ] [ 2 ] [ 3 ] Fanglomerates are poorly sorted, matrix-rich conglomerates that originated as debris flows on alluvial fans and likely contain the largest accumulations of ...