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The Cambrian Series 3 thrombolites from the Changhia Formation, at the Jiulongshan section in Shandong Province, northern China, provide an excellent example for studying the development of calcimicrobial structures. Thrombolites constructed by calcimicrobes have particular stacking patterns, which are controlled by their environments and are reflected in the relationships between micro-, meso- and macroscopic structures, requiring an approach we term “multiscopic”. Under high-energy conditions, Epiphyton A (with dense micritic bifurcating thalli) grew sporadically and adapted to the environment by taking a bushy-lateral form, because the bushy-upward form is more likely to be broken by waves or currents. Epiphyton A was fused with each other to form spotted frameworks at the mesoscopic level. The weak baffling of spotted frameworks led to the formation of low-relief tabular/lentoid macrostructures via preferential lateral accretion. In low-energy, deep-subtidal settings, Epiphyton A and Epiphyton B (with microsparry segments in the bifurcating thalli) coexisted with Hedstroemia A (with a wide terminal) and B (with a narrow terminal). These calcimicrobes grew abundantly in both the vertical and lateral directions, fusing together to form meshed frameworks, or dendritic frameworks if vertical fusion of bushy-upward calcimicrobes was predominant. The preferential vertical stacking of meshed and dendritic mesostructures highlights the ability of these frameworks to actively baffle lime mud, and ultimately to form large-domed macrostructures. Stacking patterns in these multiscopic structures help to inform environmental interpretations of thrombolites. The thrombolitic growth model we present here provides important insights into the environmental interpretations of thrombolites in other cases, especially the calcimicrobe-dominated early and middle Palaeozoic thrombolites. [ABSTRACT FROM AUTHOR]

The cement industry, as one of the primary contributors to global greenhouse gas emissions, accounts for 7% of the world's carbon dioxide emissions. There is an urgent need to establish a rapid method for detecting cement plants to facilitate effective monitoring. In this study, a comprehensive method based on YOLOv5-IEG and the Thermal Signature Detection module using Google Earth optical imagery and SDGSAT-1 thermal infrared imagery was proposed to detect large-scale cement plant information, including geographic location and operational status. The improved algorithm demonstrated an increase of 4.8% in accuracy and a 7.7% improvement in MAP@.5:95. In a specific empirical investigation in China, we successfully detected 781 large-scale cement plants with an accuracy of 90.8%. Specifically, of the 55 cement plants in Shandong Province, we identified 46 as operational and nine as non-operational. The successful application of advanced models and remote sensing technology in efficiently and accurately tracking the operational status of cement plants provides crucial support for environmental protection and sustainable development. [ABSTRACT FROM AUTHOR]

The Cambrian coral Cambroctoconus occurs selectively in the crypts of calcimicrobe Epiphyton reefs of the Zhangxia Formation (Miaolingian) in Shandong Province, North China. These cryptobionts preferentially grow laterally and/or downward, in some cases showing pendent growth from the ceilings of the reef framework. The upside‐down growth is clearly shown by the downward‐oriented aperture and the presence of fork‐like holdfasts at its base. The coral aggregations reveal two cryptic growth strategies: one involves the prevalence of far smaller individuals in vertically narrow spaces; the other involves the predominance of modular individuals in large cavernous spaces. Offset individuals frequently appear projecting downward and are connected to each other in a chain‐like fashion. Individuals often undergo rejuvenescence laterally and downward, when the growth directions may change. Therefore, the size and modularity of individuals and the direction of budding depend largely upon the cryptic microenvironments available at the time. The cryptobionts make the best use of vacant spaces by modifying the location of budding and altering their growth directions through rejuvenescence. The cryptic growth strategies found in Cambroctoconus indicate a certain degree of morphological variability in the modules. More importantly, they indicate that the individuals flexibly and exquisitely utilized the microbial crypts that were still predominant even during the middle Cambrian. These modes of cryptic growth demonstrate the age‐specific exploitation of niches by sessile skeletal organisms that was facilitated by the development of a firm attachment structure. [ABSTRACT FROM AUTHOR]

Calcimicrobes together with archaeocyaths became significant in reef construction during the early Cambrian; however, purely calcimicrobial reefs have not been as well documented as archaeocyath-bearing reefs. Here we describe the age-specific features of calcimicrobial reefs of the Zhushadong Formation (Cambrian Series 2, Stage 4) at the Sunmayu and Jinhe sections in Shandong Province, North China. The calcimicrobial reefs of the Sunmayu section are constructed mainly by Epiphyton , Kordephyton , and tubiform microbes. The reefs are in some cases dominated by Amgaina , passing from a framework of Kordephyton , Epiphyton , and tubiform microbes to dendritic growth of Epiphyton , and finally to aggregations of Amgaina. Calcimicrobial reefs in the Jinhe section are likewise constructed mainly by Epiphyton , Kordephyton , and tubiform microbes, but with subordinate Tarthinia and Bija. Epiphyton and Kordephyton as well as Amgaina were thus the main framework builders in the Zhushadong calcimicrobial reefs. Tubiform microbes contributed as encrusters, enhancing the framework rigidity, whereas Tarthinia and Bija played subordinate roles as encrusters and consolidators. Interreef deposits of the Sunmayu reefs are of peloidal or ooidal grainstone; these reefs are inferred to have formed in a high-energy shoal setting. In contrast, interreef deposits of the Jinhe reefs are of peloidal and intraclastic wackestone or grainstone with bioclasts such as trilobites and hyoliths. Tubular cavities, possibly representing burrows, are common in the spaces among frameworks. These calcimicrobial reefs are interpreted to have formed in a subtidal setting, where the water energy was lower than that in the Sunmayu section. In North China, reefs of Cambrian Epoch 2 are limited, as development of the carbonate platform began only toward the end of that epoch. The reefs of the Zhushadong Formation are therefore among the earliest on the North China Platform. The calcimicrobial reefs contain various kinds of calcimicrobes, and the calcimicrobial assemblages are similar to or more diverse than those of coeval archaeocyath-bearing reefs during this period of archaeocyath decline. Calcimicrobes thus flourished at that time and contributed greatly to the construction of reefs. These purely calcimicrobial reefs provide further information on the spatial and temporal changes in calcimicrobial diversity and reef construction during the period before and after the extinction of archaeocyaths. • Zhushadong reefs in the Jinhe and Sunmayu sections contain various calcimicrobes. • The Jinhe reefs developed in a lower-energy setting than the Sunmayu reefs. • Calcimicrobes contributed to the construction of reefs without archaeocyaths. • The reefs are some of the oldest calcimicrobial reefs in North China. • The reefs show calcimicrobial diversity around the time of archaeocyath extinction. [ABSTRACT FROM AUTHOR]