Stacking patterns and growth models of multiscopic structures within Cambrian Series 3 thrombolites at the Jiulongshan section, Shandong Province, northern China Zhen Yan a , Jianbo Liu a, ⁎, Yoichi Ezaki b , Natsuko Adachi c , Shengxian Du d a School of Earth and Space Sciences, Peking University, Haidian, Beijing 100871, PR China b Department of Geosciences, Osaka City University, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan c Department of Geosciences, Naruto University of Education, Naruto, Tokushima 772-8502, Japan d Shandong Geological Sciences Institute, Jinan 250013, PR China abstract article info Article history: Received 28 December 2015 Received in revised form 3 July 2016 Accepted 5 July 2016 Available online xxxx The Cambrian Series 3 thrombolites from the Changhia Formation, at the Jiulongshan section in Shandong Prov- ince, 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 envi- ronments 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 set- tings, 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 ulti- mately 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 impor- tant insights into the environmental interpretations of thrombolites in other cases, especially the calcimicrobe- dominated early and middle Palaeozoic thrombolites. © 2016 Elsevier B.V. All rights reserved. Keywords: Growth processes Environmental controls Epiphyton Hedstroemia Changhia Formation 1. Introduction Thrombolites are characterized by mesoscopic clots (“mesoclots”) of microbial carbonate (Shapiro, 2000). The term “mesoclot” was coined by Kennard and James (1986), to avoid confusion with submillimeter- sized clotted microstructures. Mesoclots were defined by Shapiro (2000) as simple spheroid or polylobate masses formed by microscopic cements, peloids, grumulous (clotted) fabrics and calcimicrobes. In thrombolites constructed by calcimicrobes, mesoclots are typically composed of the calcimicrobes themselves (Lee et al., 2014), whereas in thrombolites induced by microbes, mesoclots are composed of peloids or grumulous fabrics, and their characteristics may depend on the degree of microbial calcification, degradation and preservation (e.g., Riding, 2000; Turner et al., 2000). Mesoclots are fused with each other vertically and laterally to form various kinds of mesostructures (e.g., Liu et al., 2007; Ezaki et al., 2008; Wang et al., 2012), analogous to the “macroscopic clots” discussed by Aitken (1967); Pratt and James (1982), and Riding (2011), as well as the “thromboids” described by Armella (1994). These mesostructures stack vertically and accrete laterally to form tabular, domed and columnar macrostructural shapes (e.g., Shapiro, 2000; Chen and Lee, 2014). Many previous studies have documented the influence of environ- mental controls on macrostructural shape (e.g., Zhang et al., 1985; Grotzinger et al., 2005; Wang et al., 2012; Tang et al., 2013), though sim- ilar macrostructural shapes can develop in different settings (e.g., Wang et al., 2012; Tang et al., 2013), complicating their environmental inter- pretation. Some studies have investigated the influence of environ- ments on micro- and mesoscopic structures, in Cambrian Epiphyton bioherms (e.g., Woo et al., 2008; Woo and Chough, 2010) and in Triassic Palaeogeography, Palaeoclimatology, Palaeoecology xxx (2016) xxx–xxx ⁎ Corresponding author. E-mail address: jbliu@pku.edu.cn (J. Liu). PALAEO-07900; No of Pages 13 http://dx.doi.org/10.1016/j.palaeo.2016.07.009 0031-0182/© 2016 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Palaeogeography, Palaeoclimatology, Palaeoecology journal homepage: www.elsevier.com/locate/palaeo Please cite this article as: Yan, Z., et al., Stacking patterns and growth models of multiscopic structures within Cambrian Series 3 thrombolites at the Jiulongshan section, Sh..., Palaeogeogr. Palaeoclimatol. Palaeoecol. (2016), http://dx.doi.org/10.1016/j.palaeo.2016.07.009