GSA Annual Meeting in Phoenix, Arizona, USA - 2019

Paper No. 109-18
Presentation Time: 9:00 AM-6:30 PM


BOUWENS, Maegan1, DOSER, Diane I.2, ANTHONY, Elizabeth A.3 and ROHRBAUGH, Rob1, (1)Geology, El Paso Community College, 1579 Bengal Dr, El Paso, TX 79935, (2)Geological Sciences, University of Texas at El Paso, El Paso, TX 79968, (3)Dept. of Geological Sciences, University of Texas at El Paso, El Paso, TX 79968

Eocene andesite of the El Paso, TX area contain many enclaves, including angular structures further classified as xenoliths and rounded structures classified as cognates. Some of these enclaves are sedimentary xenoliths that may be used to distinguish unknown contact zones. Closer examination of the composition and distribution of these, likely shale, xenoliths may give insight into what they are composed of and how they became emplaced in the andesite. In addition, the distribution of all enclaves (cognates and xenoliths) in the area can assist in differentiating between separate magma pulses between sites and within sites. This will aid in identifying connections or separations between magma bodies at the Campus andesite, Three Sisters, Thunderbird, and Coronado outcrop sites. For my research I walked the exposed faces of each site and plotted locations of xenoliths and noted what kind they were. I then used this data to correlate with previous research on xenolith types, density, and mineralogy to establish connections between sites as well as mapping zones that could further support any connections. At this point my research is showing separated zones at each site. Three sisters was previously established to be from two separate magma pulses, my data shows three different zones at Coronado, one large mixed area at Thunderbird, and a mix of many different zones among the Campus andesite.