Intensity-ground motion data set for Italy (INGe) version 2.0

An updated and homogeneous earthquake data set for Italy compiled by joining the Italian Macroseismic Database DBMI15 and the Engineering Strong-Motion (ESM) accelerometric data bank. The database has been compiled through an extensive procedure of selection and revision based on two main steps: 1) the removal of several earthquakes in DBMI15 because the data source has been considered to be largely unreliable in the estimation of the macroseismic intensities and 2) the extraction of all the localities reporting intensity data which are located within 3 km from the accelerograph stations that recorded the data.

The final data set includes 519 recordings from 65 earthquakes and 227 stations in the time span 1972-2016. The events are characterized by moment magnitudes in the range 4.1-6.8 and depths in the range 0-55 km.

Here, we illustrate the data collection and the properties of the database in terms of recording, event and station distributions as well as macroseismic intensity points. Furthermore, we list the most relevant features of engineering interest showing several statistics with reference to the most significant metadata (such as moment magnitude, several distance metrics, style of faulting etc).

HEADER EXPLANATION

event_id: id of the event in ESM (http://esm.mi.ingv.it);

INGV_ev_id: event id in the bulletin of the Istituto Nazionale di Geofisica e Vulcanologia (INGV, http://cnt.rm.ingv.it);

event_time: time of the event (format YYYY-MM-DD HH:MM:SS);

ev_latitude and ev_longitude: geographic coordinates (decimal degrees) of the epicenter of the event;

ev_depth: depth of the hypocenter of the event (km);

erh: horizontal error (km);

erz: vertical error (km);

ev_hyp_ref: reference for ev_latitude, ev_longitude and ev_depth  (CPTI https://emidius.mi.ingv.it/CPTI15-DBMI15/; INGV_W  INGV-webservice http://webservices.rm.ingv.it; CSI Catalogo della Sismicità Italiana https://csi.rm.ingv.it/; GEM ISC-GEM Global Instrumental Earthquake Catalogue http://www.isc.ac.uk/iscgem/; ETNA1 Mt. Etna Seismic Catalog 2000-2010 http://sismoweb.ct.ingv.it/Etna/catalogs/2000_2010/; ETNA 2 Mt. Etna Seismic Catalog 2011-2013 http://sismoweb.ct.ingv.it/Etna/catalogs/2011_2013/; SL Slejko, D., Neri, G., Orozova, I., Renner, G., & Wyss, M. (1999). Stress Field in Friuli (NE Italy) from Fault Plane Solutions of Activity Following the 1976 Main Shock. Bulletin of the Seismological Society of America, 89(4), 1037–1052. BSING: Istituto Nazionale di Geofisica. Bollettino sismico mensile.)

fm_type_code: style of faulting (NF normal fault; TF reverse fault; SS strike-slip fault; O oblique fault; U undefined).

Mw: moment magnitude;

erMw: uncertainty of Mw;

Mw_ref: reference for Mw estimate (H: The Homogenized Instrumental Seismic Catalog (HORUS));

network_code: code associated with the recording network according to the International Federation of Seismograph Network (http://www.fdsn.org);

st_code: 3 to 5 characters associated to the station;

st_latitude and st_longitude: geographic coordinates (decimal degrees) of the station;

ec8_code: EC8 site category (CEN, 2003) (the subsoil class values are marked with an asterisk when they were assessed only by the surface geology)

st_vs30: vS30 associated to the station (m/s);

st_vs30_ type: type of method used to estimate st_vs30 (meas: average shear wave velocity vS,30 (CEN, 2003) from in-situ measurements (m/s); calc: extracted vS30 from the vS30 grid adopted by ShakeMap (Michelini et al., 2020);

st_to_ev_dist: station-to-event distance (km);

st_to_ev_dist_ type: type of st_to_ev_dist (RJB: distance computed from the surface projection of the fault; REPI: distance from epicentre of the event); 

epi_az: event-to-station azimuth (degrees);

PlaceID: id of the locality to which each macroseismic data point is referring to;

Placename:  place name of the locality to which each macroseismic data point is referring to;

Lat and Lon: geographic coordinates (decimal degrees) of the macroseismic data point;

Int: macroseismic intensity associated to the macroseismic data point;

Int_dec: corresponding decimal value of Int, used internally for graphing, and based on the DBMI15 manual (https://emidius.mi.ingv.it/CPTI15-DBMI15/description_DBMI15_en.htm) ;

erInt: uncertainty of Int;

Int_type: type of macroseismic scale used to estimate Int (MCS: Mercalli‐Cancani‐Sieberg scale (Sieberg, 1930); EMS-98: European Macroseismic Scale (Grünthal, 1998));

st_to_MDP_dist: station-to-macroseismic data point distance (km);

ev_to_MDP_dist: epicenter-to- macroseismic data point distance (km);

Max_PGA and Max_PGV: maximum among the two horizontal components of peak ground acceleration (cm/s2) and peak ground velocity (cm/s);

Max_TO_300, Max_T1_000 and Max_T3_000: maximum among the two horizontal components of peak response spectral acceleration amplitudes at 0.3, 1.0, and 3.0 s (cm/s2).

本数据集为经更新的均质化意大利地震数据集，由意大利宏观地震数据库（Italian Macroseismic Database DBMI15）与工程强运动（Engineering Strong-Motion, ESM）加速度数据库整合构建。

本数据库通过严谨的筛选与修订流程生成，包含两项核心步骤：1）剔除DBMI15中部分地震事件，因其数据源在宏观烈度估算方面可靠性严重不足；2）提取所有记录有烈度数据的点位，且这些点位需位于记录该数据的加速度台站3公里范围内。

最终数据集涵盖1972年至2016年期间，来自65次地震事件、227个观测台站的519条有效记录。本次收录的地震事件矩震级范围为4.1至6.8，震源深度范围为0至55千米。

本研究将从记录、事件与台站分布，以及宏观烈度点分布等维度，阐述数据集的采集过程与数据库特性；同时，结合矩震级、多种距离度量指标、断层类型等关键元数据，列出工程相关的核心特征并展示对应统计结果。

字段说明：
1. event_id：ESM数据库中的事件编号（http://esm.mi.ingv.it）；
2. INGV_ev_id：意大利国家地球物理与火山研究所（Istituto Nazionale di Geofisica e Vulcanologia, INGV）地震通报中的事件编号（http://cnt.rm.ingv.it）；
3. event_time：事件发生时间，格式为YYYY-MM-DD HH:MM:SS；
4. ev_latitude 与 ev_longitude：地震震中的地理坐标，单位为十进制度；
5. ev_depth：地震震源深度，单位为千米；
6. erh：水平定位误差，单位为千米；
7. erz：垂直定位误差，单位为千米；
8. ev_hyp_ref：ev_latitude、ev_longitude及ev_depth的参考来源：CPTI（https://emidius.mi.ingv.it/CPTI15-DBMI15/）、INGV_W（意大利国家地球物理与火山研究所网络服务，http://webservices.rm.ingv.it）、CSI（意大利地震目录Catalogo della Sismicità Italiana，https://csi.rm.ingv.it/）、GEM ISC-GEM全球仪器化地震目录（http://www.isc.ac.uk/iscgem/）、ETNA1：2000-2010年埃特纳火山地震目录（http://sismoweb.ct.ingv.it/Etna/catalogs/2000_2010/）、ETNA2：2011-2013年埃特纳火山地震目录（http://sismoweb.ct.ingv.it/Etna/catalogs/2011_2013/）、SL：Slejko, D.、Neri, G.、Orozova, I.、Renner, G.与Wyss, M.（1999）《1976年主震后活动的断层面解揭示的弗留利地区（意大利东北部）应力场》，发表于《美国地震学会通报》89卷第4期，第1037-1052页；BSING：意大利国家地球物理研究所《月度地震通报》（Bollettino sismico mensile）；
9. fm_type_code：断层类型代码（NF：正断层；TF：逆断层；SS：走滑断层；O：斜向断层；U：未定义）；
10. Mw：矩震级；
11. erMw：矩震级的不确定性；
12. Mw_ref：矩震级估算参考来源：H，即均质化仪器地震目录（HORUS）；
13. network_code：国际地震台网联合会（International Federation of Seismograph Network, FDSN）定义的观测台网代码（http://www.fdsn.org）；
14. st_code：台站编号，由3至5个字符组成；
15. st_latitude 与 st_longitude：观测台站的地理坐标，单位为十进制度；
16. ec8_code：欧洲规范8（EC8）场地类别（CEN, 2003）。若仅通过地表地质评估得到土层类别，对应值后将标注星号；
17. st_vs30：台站对应的剪切波速vS30，单位为m/s；
18. st_vs30_type：st_vs30的估算方法类型：meas指通过原位测试得到的平均剪切波速vS30（CEN, 2003），单位为m/s；calc指从ShakeMap采用的vS30网格提取得到的vS30（Michelini et al., 2020）；
19. st_to_ev_dist：台站至事件的距离，单位为千米；
20. st_to_ev_dist_type：st_to_ev_dist的计算类型：RJB指从断层地表投影计算得到的距离；REPI指事件震中至台站的距离；
21. epi_az：事件至台站的方位角，单位为度；
22. PlaceID：每条宏观烈度数据对应的点位编号；
23. Placename：每条宏观烈度数据对应的点位名称；
24. Lat 与 Lon：宏观烈度数据点的地理坐标，单位为十进制度；
25. Int：该点位对应的宏观烈度；
26. Int_dec：Int对应的十进制数值，用于内部绘图，依据DBMI15手册（https://emidius.mi.ingv.it/CPTI15-DBMI15/description_DBMI15_en.htm）制定；
27. erInt：宏观烈度的不确定性；
28. Int_type：用于估算Int的宏观烈度表类型：MCS指麦加利-坎卡尼-西贝格烈度表（Sieberg, 1930）；EMS-98指欧洲宏观烈度表（Grünthal, 1998）；
29. st_to_MDP_dist：台站至宏观烈度数据点的距离，单位为千米；
30. ev_to_MDP_dist：震中至宏观烈度数据点的距离，单位为千米；
31. Max_PGA 与 Max_PGV：两个水平分量的峰值地面加速度（单位：cm/s²）与峰值地面速度（单位：cm/s）中的最大值；
32. Max_TO_300、Max_T1_000 与 Max_T3_000：两个水平分量的峰值反应谱加速度在0.3s、1.0s及3.0s周期处的最大值，单位为cm/s²。