Curie Point Depth Estimates and Correlation with Subduction in Mexico

Abstract

We investigate the regional thermal structure of the crust in Mexico using Curie Point Depth (CPD) estimates. The top and bottom of the magnetized crust were calculated using the power-density spectra of the total magnetic field from the freely available ''Magnetic Anomaly Map of North America''. We applied this method to estimate the regional crustal thermal structure in overlapping square windows of 2°9 2°. The CPD estimates range between 10 and 40 km and show several regions of relatively shallow and deep magnetic sources, with a general inverse correlation with measured heat flow. A deep CPD region (20-30 km) is located in the fore-arc area where the subducting Cocos plate has a flat-slab geometry. This deep region is bound to the NW and SE by shallow CPD areas beneath the states of Michoacan (CPD = 12-16 km) and Oaxaca (CPD = *16 km), respectively. There is a good spatial correlation between this deep CPD area and two main fracture zones located on the incoming Cocos plate (Orozco and O'Gorman fracture zones), suggesting that subduction plays an important role in setting apart different CPD provinces along the Mexican coast. Another deep CPD (16-32 km) area corresponds to the region where the Rivera plate subducts beneath Jalisco block. The Trans-Mexican Volcanic Belt is characterized by a decrease in Curie depths from west (16-20 km) to east (10-12 km). Finally, several deep CPD areas are situated in the back-arc region where old Mesozoic terrains are present. Our results suggest that the main control on the crust's regional thermal structure in the fore-arc and volcanic arc regions is due to the subduction of the Cocos and Rivera plates beneath Mexico.

Estimating depth to the bottom of magnetic sources at Wikki Warm Spring region, northeastern Nigeria, using fractal distribution of sources approach

“…One of the methods for examining the thermal structure of the crust is the estimation of the CPD using aeromagnetic data (Smith et al, 1977;Okubo et al, 1985Okubo et al, , 1989Okubo et al, , 1994Okubo et al, , 2003Tsokas et al, 1998;Tanaka et al, 1999;Stampolidis and Tsokas, 2002;Dolmaz et al, 2005;Ates et al, 2005;Aydin et al, 2005;Qingqing et al, 2008;Li et al, 2010;Li, 2011;Bilim, 2011;Manea and Manea, 2011;Abd El Nabi, 2012;Hisarli et al, 2012;Saleh et al, 2013;Sayed et al, 2013;Abraham et al, 2014;Obande et al, 2014;Starostenko et al, 2014). Various studies have shown correlations between Curie temperature depths and average crustal temperatures, leading to viable conclusions regarding lithospheric thermal conditions in a number of regions around the world (Ross et al, 2006;Rajaram, 2007;Bouligand et al, 2009).…”

Modeled temperatures and fluid source distributions for the Mexican subduction zone: Effects of hydrothermal circulation and implications for plate boundary seismic processes

“…[] examined the effects of subducting a plate cooled by hydrothermal circulation prior to subduction along the Mexico margin, but assumed that fluid circulation stops at the trench. The effect on subduction zone temperatures is small (∼25°C cooling), leading subsequent studies to ignore the potential effects of fluid circulation [e.g., Manea et al ., ; Manea and Manea , ]. However, imposing a cessation of hydrothermal circulation in the crust immediately upon subduction was implemented out of convenience in the numerical models rather than being rooted in a physical process.…”

Statistical Analysis of Natural Water Conductivity Data Behavior in Two Wells: Seismic Coastal Border Limits of Guerrero-Oaxaca States, Mexico

“…), Figure 41. It seems that the observed behavior is possibly resulted of the local conditions related to the physical environment, which are characterized by a setting with a higher temperature in relation to the surrounding environment, 30% more [44], also is settled in a region with a complex tectonic history of magmatism and metamorphism, also the regional continental crust is probably highly fractured [37].…”