Circular structures, especially those after Mesozoic and Cenozoic, are almost regular geometric circles, and the epigenetic geological structures controlled by them are also nearly circular. The overall shape after the later structural transformation is also round after simple repair and shaping. This must start from the high energy state when the annular surge structure is formed. The ultra-high temperature and high pressure magmatic flow spewed out quickly or slowly and hit the lithosphere, which made the existing solid and plastic media rapidly remelt and transform, forming a special high-energy channel. The new material energy flow created a new cylindrical space according to the laws of fluid mechanics, but it had little effect on the transformation of the original geological structure around it, keeping it intact. However, the ejected water is extremely self-shaped, maintaining the largest cross section, that is, cylindrical, just like drilling holes in metal components or diamonds with a strong laser beam, just like in the process of rock condensation and crystallization, high-temperature minerals first form spherical phenocrysts. This feature is very strong and obvious in the round surge structure, which has obvious boundary and contrast with its peripheral medium environment. This is the internal reason why the round surge structure plays a particularly prominent role in material dynamics in the earth structure and is easy to reveal, delineate and study.

The 36 morphological patterns listed in Figure 2-7 are extracted and summarized from many real geological images at home and abroad, and will be explained in detail in separate chapters in the future. These 36 geometric shapes can be further divided into 8 categories:

(1) concentric circles: During the formation of this circular structure, deep dynamic roots basically exist in the form of spindle spatial stability or vertical fluctuation, so a circular structure is formed, keeping the same center and forming a ring with parallel periphery. This is the basic pattern of the ring structure, and the evolution of other forms is inseparable from this basic pattern [Figure 2-7 (1)].

(2) Parasitic circle: on the basis of the base circle, it crosses the boundary circle attached to the edge of the base circle in the form of tangent circle, inscribed circle, secondary gushing, etc., leading and subsequent secondary magmatic activities and these parasitic additional small gushing structures appear. Because it occurs in the late or leading period of main scouring activities, it often plays a more concentrated role than the basic background circle in the sense of mineral accumulation and dynamics. There is also a small parasitic circle, which is irregularly scattered inside and outside the basic circle. They often indicate the mineral and dynamic significance different from the main upwelling, and reflect some new geological connotations [Figures 2-7(4), 2-7(6), 2-7( 13), 2-7 (15)]. The satellite type or array type shown in Figure 2-7(2 1) is also a common distribution form, and it also has the characteristics of mutual obedience and complete symmetry.

(3) homologous twin rockburst (or Y-shaped cone rock mass): it is a phenomenon that the total beam splits into two beams at a certain depth. It is very common in high-speed jet fluid mechanics. The geometric symmetry of two beams of light is very strong, and the geological and physical properties are exactly the same. This kind of geological structure often appears in the shallow layer of the earth, and their geometric and physical-chemical symmetry can bring wonders with half the effort for studying reasoning, comparing and predicting minerals and geodynamics. For example, Guposhan-Huashan in Guangxi, Weiya-Tianhu in Xinjiang, Luding-Emei in Sichuan, Taihu-Qidong in Jiangsu and Tulasu Gold Mine in Xinjiang.

The discovery and application of this important law will greatly improve the level of geological research [Figure 2-7(2), 2-7(4), 2-7(5), 2-7(20), 2-7(26), 2-7(27), 2-7 (3/kloc-0.

(4) Linear surge structure: the surge structure is arranged in a straight line, including equicircular in-line arrangement, galaxy (lenticular envelope) and reverse envelope [Figures 2-7(7), 2-7(8) and 2-7 (9)]. This arrangement mostly occurs in the deep faults of the earth's lithosphere. Whether they hit the rift valley or deep fault and lead to the linear distribution of annular surge is still inconclusive and needs further study.

(5) Vortex arrangement: Different types of vortex structures are the main features of high-energy thermonuclear motion, which include the dual features of centripetal and geometric symmetry [Figure 2-7( 10), 2-7( 12), 2-7 (14), 2-7 (/). The vortex turbulence of geological water inrush also has regular and symmetrical material movement flow and dynamic characteristics.

(6) Eight diagrams arrangement: This arrangement has both the central characteristics of a ring and the characteristics of twin symmetry, and develops in the form of two poles, four images and eight diagrams. This classification form is also very common in geological structures, often appearing in mining areas, environmental landscapes and dynamic structures. For example, in chengde mountain resort, there are two images and Tai Chi vortex structures as shown in Figure 2-7(3). This structure also has strong symmetry and distribution law [Figures 2-7(3), 2-7( 10), 2-7( 1 1), 2-7 (12)].

Figure 2-7 Geometric classification of circular surge structure

(7) Magmatic tongue type: there is a round-headed nucleus with a strong trend, dragging an obvious dynamic wake. This kind of structure appears in the earth tectonic field in isolation, such as Drake magma tongue at the southern tip of South America and Caribbean magma tongue between North and South America. There are similar tongue-shaped structures on land, and there may be symmetrical corresponding tongue-shaped structures, which need to be further explored [Figure 2-7 (25)].

(8) The round-gushing structure and ancient round-gushing structure in the ancient crystalline basement: The ancient round-gushing structure before Mesozoic was generally reconstructed many times, with vague boundaries, certain remelting edges or staggered deformation, and generally recovered to be circular [Figure 2-7(29), 2-7 (30)]. In addition, there are combinations of eyeball shape and diamond shape [Figures 2-7(26), 2-7(27) and 2-7 (32)]. In the ancient craton, circular structures or fragments of basement circular blocks extruded by sedimentary caprocks are still common [Figures 2-7(28), 2-7(32), 2-7(33), 2-7(34), 2-7(35) and 2-7 (36)]. There are still many ring structures in these interwoven structures, and their metallogenic background and dynamic history still control and remain the geological structure, metallogenic background and dynamic environment in the later period, which still needs in-depth analysis and exploration. Therefore, it is equally important to repair, shape and rebuild ancient circular structures, because they occupy a large geological space and a long geological history.