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In the process of excavating seven parallel tunnels at the Jinping II Hydropower Station, several extremely intense rockbursts occurred, killing and injuring construction workers and damaging several sets of equipment. Based on the characteristics and mechanisms of these rockbursts, four typical events were selected and their temporal and spatial characteristics were here described in detail. The geological conditions revealed after the rockbursts were surveyed carefully. The responses of support elements were also analyzed. The details documented in each case provide not only an important reference for understanding the development mechanisms of rockbursts but also a basis for the selection and development of rockburst prevention measures in deep hard rock tunnels.

The northern piedmont of the Tianshan Mountains consists of three rows of Cenozoic EW‐striking fold and reverse fault zones, with en échelon right‐lateral steps. The southernmost row involves sediments as young as lower Pleistocene, but there is no evidence of activity along this row during the last 30,000 years. The central row is composed of three linear anticlines (Houerguos, Manas, and Tugulu) and associated reverse faults. The northernmost row includes the Dushanzi, Halaande, and Anjihai anticlines and their associated reverse faults. Abundant fault scarps and folds of late Pleistocene to Holocene river terraces across the anticlines within the central and the northernmost rows indicate recent folding and reverse faulting. We divide the northern piedmont into the Dushanzi and Manas fold and reverse fault zone. In the Dushanzi zone, we excavated 15 trenches across scarps controlled by reverse faults and back thrusts. By comparing 11 trench logs among the 15 trenches, we identify three paleoearthquakes since 13,000 years B.P. The first event occurred between 11,300 and 13,300 years B.P., and the second and the third events occurred 6300–8400 and 3000–5000 years B.P., respectively. Considering the uncertainties of the data, the average recurrence interval for large earthquakes in the Dushanzi zone is about 4000 years. A large earthquake along this zone is expected in the near future because the elapsed time since the last surface‐rupturing event is already 3000–4000 years. Three large trenches and several small trenches excavated across the fault scarps along the Manas fold and reverse fault zone reveal four events. The first, second, and third events occurred at 18,000–13,000 years B.P., 11,300–10,500 years B.P., and 6900–3600 years B.P., respectively. The fourth, the latest one, is the 1906 M = 7.7 Manas earthquake. Field investigation suggests that the 1906 Manas earthquake occurred along a blind thrust fault. This earthquake formed three discontinuous zones of fresh surface ruptures, the longest of which is only 8 km long along the eastern segment of the Tugulu reverse fault, and was associated with a zone of uplift 130 km long related to the Manas earthquake. The average recurrence interval along this zone is probably 5000–6000 years. Therefore it is unlikely that a large earthquake will occur along this zone in the near future because the Manas earthquake occurred only 89 years ago.

Histone lysine methylation can be removed by JmjC domain-containing proteins in a sequence-and methylationstate-specific manner. However, how substrate specificity is determined and how the enzymes are regulated were largely unknown. We recently found that ceKDM7A, a PHD-and JmjC domain-containing protein, is a histone demethylase specific for H3K9me2 and H3K27me2, and the PHD finger binding to H3K4me3 guides the demethylation activity in vivo. To provide structural insight into the molecular mechanisms for the enzymatic activity and the function of the PHD finger, we solved six crystal structures of the enzyme in apo form and in complex with single or two peptides containing various combinations of H3K4me3, H3K9me2, and H3K27me2 modifications. The structures indicate that H3K9me2 and H3K27me2 interact with ceKDM7A in a similar fashion, and that the peptide-binding specificity is determined by a network of specific interactions. The geometrical measurement of the structures also revealed that H3K4me3 associated with the PHD finger and H3K9me2 bound to the JmjC domain are from two separate molecules, suggesting a trans-histone peptide-binding mechanism. Thus, our systemic structural studies reveal not only the substrate recognition by the catalytic domain but also more importantly, the molecular mechanism of dual specificity of ceDKM7A for both H3K9me2 and H3K27me2.

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