Amanda R Hintz SUNY University at Buffalo May 29, 2009

Long-term volcanic field behavior Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline Provide new insights to the overall nature of volcanic fields Improve the understanding of processes governing the evolution of volcanic fields and long-term hazard issues Image Credit: 5 km

Volcanic field variability Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline What are the processes that ultimately control the timing, distribution, eruptive behavior of volcanic fields? Present state of knowledge There is a need to characterize these fields’ activity and behavior to properly advance our understanding of basaltic volcanism and potential hazards Image Credit: Priest et al. (2001)

Volcanic fields are the result of a complex relationship between tectonics and magma influx Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline The Lunar Crater volcanic field (LCVF) may represent an intermediate volcanic field Work will focus on characterizing the field in terms of its long-term time- volume behavior and identifying patterns between the LCVF and other volcanic fields

Regional geology and structure Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline Image Credit: Foland and Bergman (1992) Image Credit: Crowe et al. (1986)

Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline Image Credit: Smith et al. (2002) 5 km Image Credit: ngton.edu/EPIC/Collecti ons/Dohrenwend/ Eruptive History

Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline Geochemistry Image Credit: Yogodzinski et al. (1996) Reveille Range et al. Image Credit: Dickson (1995) LCVF

Rationale Divisions Physical volcanology, scales Structural and topographic relationships Volumetrics Time-volume behavior Hazard assessment Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline

Objective : Make determinations about eruptive styles and behaviors based on physical observations to elucidate a potential correlation between volcanic fields Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline Lunar Crater Maar

Observations and measurements of; Lava flows Pyroclastic cones Phenocryst, xenolith and lithic assemblages Feeder dike length scales Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline Mantle xenolith from Easy Chair Maar Scoria outcrop near Easy Chair Crater

Working with existing maps Separation and definition of units Clarification Volcanic event Rafts Stratigraphic relationships Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline Image Credit: Modified from Snyder et al. (1972) and Dickson (1995)

Image Credit: Dohrenwend et al. (1987) Geomorphic relationships Burial by sediments Formation of desert pavement on lava flows Erosion and weathering Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline Examples of desert pavement formation. Top: better formed desert pavement on older lava flow. Bottom: desert pavement is not well formed on younger flow

Vent and fault patterns Alignments Intersections En echelon Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline Image Credit: Dickson (1995) Objective: To use the volcano-tectonic interactions in the LCVF to help distinguish the field’s underlying controls

Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline Reveille Range Dike-fault interactions Near surface dike morphology, i.e. shallow plumbing Topographic relationships

Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline Image Credit: mg206/8048/differencexrayis9. jpg Image Credit: Image Credit: e.com/images/560/para_0 3.jpg Based on; Topographic and geologic maps DEMs and other ‘xyz’ data available Field observations Model

Objective: To delineate the eruptive history and time-volume relationships at LCVF to determine the relationship fundamental controls on volcanism in volcanic fields Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline Image Credit: Valentine and Perry (2007) Image Credit: Valentine and Perry (2006) Volume calculations and feeder dike length scales will be used to estimate the ratio of tectonic to magmatic control

Time-volume behavior is a first order approximation on the long-term behavior of volcanic fields Individual fields should also be assessed with a probabilistic approach Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline

Resources on hand Mapping, computers, software, field equipment Needed resources Potential software for volume model Additional radiometric dating Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline Image Credit: Greg Valentine (2008)

Potential Problems Unable to work out eruptive history Unable to create volume model LCVF does not show a correlation with the time- volume behavior hypothesized Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline Alternatives Calculate by hand Use area (?) Limitations Exposures Software expertise Effects on interpretations and conclusions Large errors Erroneous hazard analysis Image Credit: NASA

Support of hypothesis LCVF shows characteristics of both magmatically and tectonically controlled volcanic field Products Model to evaluate interlocking and overlapping scoria cone and lava flow volumes Detailed maps Volcanic field database Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline

Impacts Broadening the understanding of volcanic field behavior Increasing the fundamental knowledge of basaltic volcanism through better models of the timing and distribution of eruptions within volcanic fields Potential applications to determining links between monogenetic and polygenetic volcanism Providing the volcanological community with a case study of young volcanism and its potential eroded analogs Hazard analysis Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline

Overview Introduction and Significance Background and Geology Methods and Analysis Resources Limitations Implications Results Timeline