We studied long-term evolution of nontransform discontinuities (NTDs) on the Mid-Atlantic Ridge from 0-to~20-to 25-Ma crust using plate reconstructions of multibeam bathymetry, long-range HMR1 sidescan sonar, residual mantle Bouguer gravity anomaly (RMBA), and gravity-derived crustal thickness. NTDs have propagated north and south with respect to flowlines of relative plate motion and both rapidly and slowly compared to the half spreading rate; at times they have been quasi-stable. Fast, short-term (<2 Myr) propagation is driven by reduced magma supply (increased tectonic extension) in the propagating ridge tip when NTD ridge-axis offsets are small (≲5 km). Propagation at larger offsets generally is slower and longer term. These NTDs can show classic structures of rift propagation including inner and outer pseudofaults and crustal blocks transferred between ridge flanks by discontinuous jumps of the propagating ridge tip. In all cases crustal transfer occurs within the NTD valley. Aside from ridge-axis offset, the evolution of NTDs appears to be controlled by three factors: (1) gross volume and distribution of magma supplied to ridge segments as controlled by 3-D heterogeneities in mantle fertility and/or dynamic upwelling; this controls fundamental ridge segmentation. (2) The lithospheric plumbing system through which magma is delivered to the crust. (3) The consequent focusing of tectonic extension in magma-poor parts of spreading segments, typically at segment ends, which can drive propagation. We also observe long-wavelength (5-10 Myr) RMBA asymmetry between the conjugate ridge flanks, and we attribute this to asymmetric distribution of density anomalies in the upper mantle. Key Points:• Propagation of non-transform discontinuities on the Mid-Atlantic Ridge was analyzed in reconstructions of bathymetric and gravity data • Rapid and slow propagation occurs and is controlled by magma distribution within the mantle and crust of spreading segments • We attribute long-wavelength cross-axis asymmetry in gravity anomalies to asymmetric distribution of density anomalies in the upper mantle Supporting Information:• Supporting Information S1• Movie S1 • Movie S2 Figure 1. (a) Multibeam bathymetry of the study area (within the black dashed lines) superimposed on bathymetry derived from satellite gravity (Sandwell et al., 2014). Spreading segments are labeled from A to J. Nontransform discontinuities (NTDs) and the Mid-Atlantic Ridge (MAR) axis are shown by solid black lines. The labeled white lines are major chrons; their ages, top left, are based on Ogg (2012). The red dashed lines are calculated flowlines of relative plate motion, anchored where NTDs offset the present ridge axis. The white stars locate significant oceanic core complexes. The inset locates the study area in the North Atlantic (KFZ, Kane fracture zone; AFZ, Atlantis fracture zone). (b) Residual mantle Bouguer anomaly (RMBA) within the study area (Wang et al., 2015) superimposed on satellite-derived RMBA from Lin and Zhu (2015); the contour interval is ...

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People’s lives are undergoing tremendous changes with the development of the times. Compared with the past, people’s pursuit of spiritual and cultural life also makes our education field usher in a huge development to adapt to the changes in the context of the times. But, at the same time, the development of labor education is gradually being downplayed by people, resulting in a series of problems such as people preferring comfort and not working. Aiming at this common problem, this paper will use the ant colony algorithm and particle swarm optimization algorithm in the computer intelligent algorithm to optimize the way of labor education. It includes the principle and basic process of the ant colony algorithm, the establishment of the mathematical model of the original ant colony algorithm, and the improved algorithm of the ant colony algorithm. The research results of the optimization method of labor education showed the following: when the number of ant colonies reaches 51, the number of iterations of the algorithm will be the least, and the corresponding shortest path is also the best solution; when the combination of pheromone intensity and volatility factor is 3, the optimal solution can be quickly found, and the algorithm inflection point of MMAS is 44.82. From the research results, it can be seen that the computer intelligent algorithm has a good choice for the optimization of labor education and can achieve a major breakthrough in the traditional model of labor education.