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1988至1990年，青海地区发生了4次震级大于6．0的强震。利用GDSN宽频带波形资料，通过波形模拟，结合地质构造的背景资料对这几次地震进行了震源破裂和发震构造背景的研究。使用台站的准震源时间函数（qSTE）和准时间差（qTD）的分析方法，对震源的复杂性进行了讨论。1988年11月5日沱沱河沿Ms6．3地震是一个由两次子破裂组成的复杂震源过程的地震；1990年1月14日茫崖Ms6．1地震发生于重力异常带的交汇处，破裂扩展方面与断层走向一致；1990年4月26日共和Ms6．9与mb6．3地震的震源过程更为复杂，Ms6．9地震由两次子破裂组成，约30s后发生的mb6．3地震是一个独立于Ms6．9地震的大破裂。本文的研究从震源分析的角度进一步支持了青藏高原东北部构造应力的压力轴为接近水平的NE向，随着向青藏高原北部的推移，其构造应力的压力轴逆时针转为接近水平的NEE或N－S向的结论。
From 1988 to 1990, four strong earthquakes of magnitude 6.0 occurred in Qinghai. By using the GDSN broadband waveform data and the waveform simulation and the background data of the geological structure, the authors made a study on the source rupture and seismogenic tectonic setting of these earthquakes. The complexity of the source is discussed using the station’s quasi-hifi time function (qSTE) and quasi-time difference (qTD) analysis. On November 5, 1988, the Ms6.3 Earthquake on the Tuotuo Riverside is an earthquake with a complex source process consisting of two sub-fractures. On January 14, 1990, the Mangya Ms6.1 earthquake occurred at the junction of gravity anomalies and fractured The extension of the fault is consistent with that of the fault. The source process of the Ms6.9 and mb6.3 earthquakes on April 26, 1990 is more complicated. Ms6.9 earthquake consists of two sub-fractures and the mb6.3 earthquake occurred about 30 s A large rupture independent of the Ms6.9 earthquake. The study in this paper further supports that the pressure axis of the tectonic stress in the northeastern Qinghai-Tibet Plateau is close to the NE direction from the point of view of focal point analysis. As the pressure moves to the north of the Qinghai-Tibet Plateau, the tectonic stress axis turns counterclockwise to near-horizontal NEE Or N-S to the conclusion.