Geological History Of Adair Park South West Arizona

I. On Saturday, November 16, 2013, our Geology class went to Adair ball put Yuma Arizona on our adventure of a lifetime. The point of the trip was to slang real life examples of some of the debasegs that we have studied over the give of this semester. Actually being able to elate examples of such things as cross-bedding close ins, uncon inningities, folds faults and variant aqueous take ins. II. The first stop of the theater of study trip was to flavour at the Gneiss. The Gneiss has been nigh for some 1. 6 bilion years. The probable type of contact metamorphism The normal term for all such incorporated bodies is inclusions.Xenoliths atomic number 18 usually reconstituted by the processes of contact metamorphism, in which heat and fluids cause mineralogic and chemical changes in the grow rock of the xenolith a study of these changes can give information on the temperature and composition of the magmatic body. The mineral compostition that what we could see were Biot ite, Muscovite and quartz. The opposite significant feature the dikes(white) that was younger in the cross cuting through the Gneiss. III. The second stop of this field trip was to pick up at the Granite. The Granite and has been here for around 1. 4 one thousand million years.The type of rock Granite which is Igneous with a funeratic course grined, with grains visible on fresh surface. The type of mineral composition in the Granite is Orthoclase, Quartz and Biotite. IV. The trinity stop of this field trip was to look at the Pegimatite. The Pegmatite has been around for about 73 million years. Pegmatite is very coarse granite. Pematieites are thought to form from the bolatile low-denisity fluids that crystallize last from the grainitic magma. V. The fourth stop of this field trip was to look at the Red Beds. The red beds have been in the area around 20-30 million years old.The steep cliffs of Adair Park and the surrounding lowlands offer pulseless exposures of the lower subun itthe red conglomerates/breccias and gypsum. These red-bed deposits are composed of interbedded breccias, conglomerates, sandstones. In some other areas it commonly forms a medium thin, dirty, discontinous bed up to 10 60 cm thin beds are usually well sorted, clast-supported, commonly commonly graded.The conglomerates are also thinly bedded and clast-supported, but are reasonably well-sorted to poorly sorted and contain an abundance of angulate to well-rounded quartz, feldspar,calcite, granite and gneiss. metamorphic, and mafic volcanic clasts. The conglomerates can generally be distingushed from the breccias by their well-bedded nature. VI. The fifth stop of this field trip was to look at the Green/Tan Beds. The cat valiums and suntan beds have been in the area around 20-30 million years old. These green and tan bed deposits are compsed of gypum. On other areias it commony forms a thin disconintuous bed up to 10 cm thin are usually well sorted , clast-supported commonly ord inarily well sorted, commonly normally graded.The gypsum are also thinly bedded and poorly sorted, but are mederatelywell-sorted to poorly sorted and contain an abundance of angular calcite, and hornblend. See variant 2. VII. The sixth stop of this field trip was to look at the diobase dike. This diobase dike have been here less than 10 million years. The diobase dike are composed of a metamorphic- plutonic basement that is overlain by middle tertiary sedimentary and volcanic rocks.. Much of thesedimentary sequence was deposited before the onset of volcanism and tectonism, although the local anaesthetic presence of clasts of volcanic origin suggests at least some synchroneity.The sedimentary rocks are commonly in low-angle normal fault contactwith be basement rocks. Gentle folding and warping, along with poorly developed cleavage, are generally present. Tertiary volcanic rocks are dominantly intermediate to mafic flows with lesser amounts of pyroclastic material. Olivine, augmit e and green poroxy is largely altered. See Figure 1. VIII. The s even offth stop of this trip was to look at the Terrace Gravels. The terrace gravels have been around for around two hundred,000 years. An angular unconfomity of Adar formation with the overlying terrace gravels. In some place of Adair park the terrace gravels can be as much as 200 feet thick.The were mountains that used to be in the area but with water erosion the mountains dispareared. Bajada, ( Spanish slope ) is a broad slope of debris splay along the lower slopes of mountains by descending streams, usually found in arid or semiarid climates the term was adopted because of its use in the U. S. Southwest. A bajada is often formed by the coalescing of several(prenominal) alluvial fans. such coalescent fans are often mistaken for erosional landforms known as pediments. The repeated change of a debouching stream from one side of a fan to the other spreads the sediment widely and almostuniformly.As the sediment eve ntually grows together, the slope may extend outward from the mountain front to a distance of several kilometres. A bajada is usually composed of gravelly alluvium and may even have large boulders interbedded in it. XL. Inconclusion the field trip really helped me remove some of the stuff that we studied during this course being able to see some real examples and havintg them explained to us. This has been fun class any your are owing(p) professor. I appreciate your sense of humor during the class and your attempt to make learning fun.