新30井数字化水位、水温远场大震同震响应初析

收集了2007年以来新30井数字化水位、水温远场大震同震响应观测数据,总结了其同震响应特征.新30井数字化水位和水温对不同震中距强震的同震响应在一定程度上存在着一致性,水位通常为先振荡(以振荡居多)后下降,而水温则通常表现为下降.统计结果显示,新30井水位对地震的同震响应灵敏性优于同井水温观测.     

腾冲台水温、水位对尼泊尔8.1级地震的同震响应特征分析

介绍了腾冲台水温、水位观测井的地理位置、地质构造条件和水温、水位仪器布设、运行情况。对腾冲台水温、水位以及尼泊尔8.1级地震的同震响应特征分析,结果显示:尼泊尔8.1级地震引起的腾冲台水温、水位同震响应表现形态为水位下降-水温上升型,同震效应表现非常显著。水温同震响应滞后于水位同震响应。当水位产生同震响应时,水震波引起井孔内不同温度层位的井水多次对流和掺混,致使水温产生同震响应变化。水位同震响应持续时间比水温持续时间短,但水位的响应程度相比水温要剧烈。     

新04井水位及水温同震响应特征分析

应用新04井自2001年进行数字化改造以后的观测资料,对该井记录到的6次8.0级以上强震引起的同震变化特征进行了分析,得到以下认识:1)新04井对地震的同震响应在形态上,水位均表现为阶变上升,水温则表现为快速上升、快速恢复的突跳型变化。水温表现出的突跳型同震效应是新04井具有冷热两层地下水这种特殊水文地质条件所决定的;2)水位、水温对地震的响应存在明显的差异。无论是出现同震效应的次数还是效应的明显程度上水温都优于水位。表现出新04井水温反应地下应力应变较水位灵敏;3)新04井地下流体同震响应的明显程度与地震震级有明显的相关性。     

九江1井水温动态变化特征

以九江1井水温观测资料为研究对象,主要选取2010—2015年观测数据进行重点分析。研究发现:九江1井水温日变稳定。多年趋势向上,初步判断为观测仪器零漂。水温年动态与同井水位年动态呈负相关关系,与降水补给有关。水温对远大地震有同震响应,响应特征为突降后逐渐恢复正常,主要原因为井水震荡,上层冷水混合。     

小江断裂带地下流体记震能力分析

收集并整理了云南地区小江断裂带附近十口流体观测井对印度尼西亚苏门答腊4次8级以上地震的响应资料．并对各观测井的记震能力及其流体测项间的响应协调性进行了统计分析。分析结果显示：物理量观测项的记震能力强于化学量观测项,水位测项的记震能力强于水温测项：小江断裂带南端各观测点的记震能力强于中部及北端各观测点：水位的同震响应形态多表现为震时振荡,而水温则多表现为震时脉冲下降。最后分析了记震协调性较好的高大、弥勒和嵩明三井的记震特征。     

2015年尼泊尔MS8.1地震引起的井水位与井水温同震效应及其相关性分析

尼泊尔M_S8.1地震引起中国大陆大量地震观测井水位和水温的同震响应. 从宏观结果看, 在54个同时存在水位和水温同震效应的观测井中, 有51口观测井的变化类型为水位上升-水温上升、 水位下降-水温下降、 水位振荡-水温上升或下降(以下降为主), 井水位与井水温同震效应表现出良好的相关性, 这可能与地下水动力学作用有关; 有3口观测井的水位变化与水温变化方向相反, 且水温变化均为震后效应. 另外, 有1口观测井水位无变化而水温同震效应明显. 这些不同类型的同震变化与井孔条件、 水温梯度、 传感器位置及水位埋深等多种因素有关. 从微观结果看, 井水位同震效应出现的时间及变化幅度与井水温同震效应出现的时间及变化幅度之间的关联性比较复杂, 这与井孔条件和温度梯度等因素有关.      

2022年芦山MS 6.1、马尔康MS 6.0地震井水位、水温同震响应特征

基于全国地震地下流体台网数据,分析了芦山M_S 6.1、马尔康M_S 6.0地震引起的地下流体井水位、水温同震响应特征。结果表明,对于芦山M_S 6.1地震水位同震响应观测井数量较多,以上升变化为主,同震变化幅度较大;而对于马尔康M_S 6.0地震水位同震响应观测井数量较少,以振荡为主,变化幅度较小;2次地震引起的水位同震响应能力均强于水温测项,水温记录同震响应的前提是同井能记录到水位同震变化;2组地震引起的同震响应特征差异主要与震源机制解、台站分布密度、同震响应机理不同等有关。     

云南地下流体对尼泊尔8.1级地震的同震响应特征分析

统计云南地下流体对尼泊尔8.1级地震的同震响应情况,分析和总结了水位和水温数字化资料的同震响应特征。结果表明:尼泊尔8.1级地震对云南地区的影响较大,其流体宏观与微观动态有较显著的同震响应。水位与水温对该大地震的记震能力明显高于水氡和水质;不同井水位、水温同震响应最大振幅、持续时间相差很大,其变化形态水位以波动及阶升为主,水温表现为上升或下降—恢复;从主震与最大强余震的记录来看,震级越大,同震响应出现比例越高,且在同井中响应幅度越大,持续时间越长;同井不同仪器记录的同震幅度和持续时间不同;水温同震响应均出现在有水位同震响应井中,表明井水位与水温同震响应是密切相关的,且井水温同震响应多由井水位同震响应引起。     

宾川井对印尼大震的同震响应特征及其机理解释

系统统计分析了云南宾川井水位与水温对印尼苏门答腊4次大震的同震响应资料。 宾川井在这4次强震中的同震响应形态表现为水位振荡—水温下降和振荡停止(减弱)—水温恢复。 进一步的分析表明, 水位与水温的变化幅度与震中距、 震级有一定的统计关系。 分别探讨了水位振荡—水温下降和振荡停止—水温恢复现象产生的机理, 综合分析了前人所提出的同震响应机理, 并依据宾川井实际观测资料对机理进行了定量化的数值模拟。 模拟结果显示, 气体逸出、 热弥散及冷水下渗作用都可以导致井水温度下降, 而水温的恢复则主要是与围岩发生静态热传导所致。     

日本9.0级地震引起新30井水位水温同震响应及震后效应特征分析

分析了日本MS9.0地震引起的新疆温泉30井水位、水温同震变化特征。结果显示,该观测井水位同震响应和震后效应不论是响应起始时间还是阶变时间均早于水温的同震响应和震后效应的起始时间;此次日本地震引起的该观测井水温同震响应和震后效应均为阶升型,说明水位同震升降性质受控于当地的地质构造环境和水文地质条件,而水温同震变化还与地震波引起的井孔中水的运动方式、水温探头放置的位置等因素有关。     

日本9.0级、苏门答腊8.6级地震新疆地区水位、水温同震响应特征分析

对新疆地区4个流体测点的水位、水温资料在日本9.0级地震和苏门答腊8.6级地震后出现的同震响应及其特征进行了分析.结果显示,水位、水温资料对于远场强震的同震响应无相对固定变化形态,但同震响应可能具有一定的前兆指示意义.     

远场大震的水位、水温同震响应及其机理研究

深井水温观测在中国已经开展了20年,但目前对于水温响应机理的研究还不充分。在对2004年12月26日印尼苏门答腊MS8.7地震后,中国地下流体观测井网中121个观测井水位、水温同震响应特征的研究中,作者发现了具有规律性的一类变化类型:当某些观测井水位出现振荡的时候,其同井水温绝大多数会出现几十分钟到数小时的下降—恢复过程。为了对此现象进行验证,又收集了河北唐山矿井2001年数字化以来39次远场大震水位、水温的同震响应资料,发现其具有相同的规律。在对可能造成水温下降的影响因素研究分析的基础上,提出了同震水温下降的气体脱逸模式,给出了在气泡脱逸过程中造成水温下降的2种主要影响因素,并利用此模式对部分观测现象进行了较合理的解释     

新疆北天山地区井水位同震响应特征分析研究

通过整理新疆北天山地区的水位观测资料,分析了2011年后发生在北天山地区的4次近场6级地震所引起的水位同震响应特征。结果显示,井孔对于近场地震的同震响应主要表现为振荡—阶变复合型、阶变型,同一地震对于不同的井孔可能呈现出不同的响应特征,同一井孔对于不同的近场地震也可能具有不同映震效果,水位对近场地震的同震响应并无固定的响应特征,而是受到多重因素的控制作用,而震后效应的各不一致,则显示出不同地震对于各个井孔附近区域应力场调整的能力。     

Characteristics and Mechanisms of Co-seismic Groundwater Responses in Tayuan Well

Co-seismic responses of the groundwater level and temperature in the Tayuan well of 68 earthquakes (M_S≥7.0) from January 2004 to September 2007 were analyzed. Results show that the Tayuan well has a strong ability to record large earthquakes worldwide, and the co-seismic response shows a pattern of water level oscillation → temperature decrease→ oscillation stop → temperature resumption. Further analyses indicate that the amplitude of the water level and temperature change is not only concerned with the epicenter distance and magnitude, but is also related to the temporal state of aquifer while the seismic wave arrives. Mechanisms of water level oscillation, temperature decrease, water level oscillation stop and temperature resumption are discussed, with the results from previous research on the co-seismic response mechanisms analyzed. These include gas escape, heat diffusion and cold water seepage. Results show that a single mechanism could not explain the co-seismic response of the Tayuan well water level to multiple earthquakes; the results were garnered from a variety of jointly acting mechanisms.     

The Co-seismic Response of Underground Fluid in Yunnan to the Nepal MS8.1 Earthquake

In this paper, statistics are taken on the co-seismic response of underground fluid in Yunnan to the Nepal M_S8.1 earthquake, and the co-seismic response characteristics of the water level and water temperature are analyzed and summarized with the digital data. The results show that the Nepal M_S8.1 earthquake had greater impact on the Yunnan region, and the macro and micro dynamics of fluids showed significant co-seismic response. The earthquake recording capacity of water level and temperature measurement is significantly higher than that of water radon and water quality to this large earthquake; the maximum amplitude and duration of co-seismic response of water level and water temperature vary greatly in different wells. The changing forms are dominated by fluctuation and step rise in water level, and a rising or falling restoration in water temperature. From the records of the main shock and the maximum strong aftershock,we can see that the greater magnitude of earthquake, the higher ratio of the occurrence of co-seismic response, and in the same well, the larger the response amplitude, as well as the longer the duration. The amplitude and duration of co-seismic response recorded by different instruments in a same well are different.Water temperature co-seismic response almost occurred in wells with water level response, indicating that the well water level and water temperature are closely related in co-seismic response, and the well water temperature seismic response was caused mainly by well water level seismic response.     

Co-seismic Water Level and Temperature Responses of Some Wells to Far-Field Strong Earthquakes and Their Mechanisms

The observation of water temperature in deep wells has been carried out for more than 20 years in China.However,study on the mechanism of water temperature response to earthquakes is inadequate.During the study of the co-seismic response characteristics of water level and temperature in 121 wells within the China subsurface fluid monitoring network at the time of the December 26,2004,M-S8.7 Indonesia earthquake,we found regular response characteristics,that is,when the water level in a deep well oscillates,the water temperature in the same well will mostly experience a cycle from dropping to restoration at the same time.The process will continue for dozens of minutes to several hours.In order to confirm the observed phenomenon,we collected the digital water level and temperature observation data for 39 far-field strong earthquakes from the Tangshan well in Hebei Province(with the data set beginning in 2001).The same response characteristics were observed.Based on the analysis of the influencing factors that may cause the water temperature drop,the authors suggest the gas escape mechanism for co-seismic water temperature drop and posit two main factors that influence the water temperature drop during the process of gas escape.Finally,the authors provide a rational explanation of some observed phenomena based on the mechanism.     

河北冀16井水温动态分析

对河北冀16井2018-2019年水温动态特征、同震效应及干扰因素等方面进行分析,结果表明,水温整体呈趋势性下降变化,年、月、日动态规律清晰,对人为干扰、自然环境等干扰因素反应灵敏;该井水温固体潮效应明显,与水位呈反向变化,滞后水位1~2 h;水温对远场大震有同震响应,能记录到全球7级以上地震,响应特征为振荡后逐渐恢复正常。     

海南琼海加积井水位对远大震的同震响应特征研究

In this study,we analyze the co-seismic response of water levels in the Jiaji well to strong earthquakes(MS≥7.8) from 2001 to 2010 at an epicentral distance less than 8000km.We investigated the co-seismic variation form of water levels,and analyzed the relationship between the amplitude of water level variation and the magnitude and the epicentral distance.We then checked the seismic wave phases when the changes of water level occurred.It was shown that:(1) the water level’s co-seismic response is mainly characterized by escalation with no oscillation;(2) the amplitude of water level change has a certain connection with epicentral distance and magnitude;(3) co-seismic response of water levels in the Jiaji well shows a certain directivity;(4) most of the co-seismic responses were caused by surface waves,and some by long-period S waves.     

自流井水位响应能力与水柱高度关系的分析

分析了万全等４口自流井水位阶变、固体潮幅度与水柱高度的关系。结果表明，当含水层所受应力状态不变，水位观测条件相同时，水位阶变、固体潮幅度度与水柱高度有正相关系。