My thoughts on determining a natal chart for an area of land were that the orb of a certain degree and cardinal, fixed, or mutable group could be found in major event charts for the area. For example, 3° Leo could be in one chart and 4° Aquarius or 2°Scorpio could be in other two charts. This is a correlation I use to find a position in a chart that requires rectification.
I chose the Chicago area because I have a natal chart for the city in which the rectified angles are fairly accurate and a portion of the city’s land area sustained a recorded earthquake 33 years before the city was incorporated. I compared a pre-Chicago earthquake to three post-Chicago earthquakes and found a correlation between the pre-Chicago chart and two post-Chicago charts; 0 to 2° cardinal. All of the earthquake charts correlated with the Chicago city chart, but not by the 0 to 2° cardinal position. It could be that the 0 to 2° cardinal position is important in general. More research is needed to determine if this is the case or if it has some bearing on a natal chart for the land.
I published a post on the Fort Dearborn earthquake in 2015. I relied on Earthquake Information Bulletin, Volume 4, Number 3, May-June 1972, published by USGS. The link in my past post to the USGS source no longer works. I searched for another source for the bulletin and found another USGS reference; a free Google Ebook – The New Madrid Earthquake by Myron L. Fuller. On page 11, Fuller gives an earthquake time of 2:10 PM on August 20, 1804. The earthquake was reported as being “severe.” It was surmised that a fault line existed between Fort Dearborn and Fort Wayne, Indiana, approximately 200 miles away.
On April 18, 2008, at 4:36 AM, a 5.2 magnitude earthquake shook the Chicago area. The epicenter was near New Salem, Illinois; a town approximately 230 miles south of Chicago. “The quake shook skyscrapers in downtown Indianapolis, about 160 miles northeast of the epicenter, and in Chicago’s Loop, 230 miles north of the epicenter….Chicago officials were checking structures downtown to ensure there was no damage.”1
A 5.4 magnitude earthquake was felt in the Chicago area on November 9, 1968. The earthquake’s epicenter became known as the Cottage Grove fault. The fault extends about 70 miles, between Saline-Gallatin county and Jackson county in Southern Illinois.
The USGS rated the May 26, 1909 earthquake, centered near Aurora, at 5.1 magnitude. The earthquake occurred at 5:37 AM. An article in the Chicago Examiner gives an account of the event. An excerpt of the article is below. The article is difficult to read, so I typed it and saved it to my Google Drive. You can click the Google Drive link to read all of it, if you like.
Chicago was rocked by an earthquake early yesterday and half of the population remembering the San Francisco and Messina horrors, feared a similar disaster….One big shock was followed by two lesser ones and big skyscrapers in the downtown district trembled like ague-stricken human beings. Many dilapidated old structures collapsed in different parts of the city, dishes were thrown off shelves and broken, windows were cracked in the residence districts of Maywood, Evanston and other suburban towns.- Chicago Examiner May 27, 1909
1. 5.2 Earthquake Rocks The Midwest. Retrieved 9:57 AM on December 30, 2016. http://abc7chicago.com/archive/6088574/