What is the talk mainly about?

[[Professor] (female)] Is everyone ready to begin? Well, let me start by saying it all started in
   Dahlonega, Georgia.
[Student A (male)] Huh? What started there?
[Professor] I’m getting to that. Q10 But first, does anyone have any idea what I’m
   talking about? Dahlonega, Georgia, is known for somethi-
[Student B (male)] [interrupting]Oh! I know! Dahlonega is where the gold rush started!
[Student A] Wasn’t that in California?
[Professor] You’re both right. Q6 Georgia was the site of a gold rush...and California was
   too. That’s actually what I want to talk about today: these two North American
   gold rushes.
   I guess you could say that a zeal for gold has, um, long been a part of the
   national psyche of the United States. If you think about it, the prospect of gold
   was basically what brought colonists here in the first place. Q9(A) As early as
   the sixteenth century, the Spanish and French may have been mining gold in
   Georgia, but the real gold rush didn’t begin until much later. Um, 1829, to be
   more precise.
   Q7 So how did the gold rush officially start? Well, we don’t quite know
   for certain...and there’re a couple of different, um, anecdotes about it. One
   suggests that someone named Frank Logan discovered some gold in Dukes
   Creek. A similar story indicates that the gold found in Dukes Creek was actually
   discovered by a guy named John Witheroods. Yet another tale credits the
   discovery of gold to Jesse Hogan, who found gold near Dahlonega. Whatever
   the case may be, gold was discovered in Georgia in 1828...tales of riches spread
   quickly throughout the nation, and soon prospectors from all over the country
   were suffering from "gold fever"...packing up their belongings and heading to
   Georgia to get rich.
   Q11 Dahlonega was the center of it all. Actually, the name "Dahlonega"
   is from the Cherokee word for gold. Within a couple of years, the population of
   Dahlonega swelled to 15,000 miners -um, according to the 2000 census,
   it has a population of less than 4,000 people today.
[Student B] When you mentioned that Dahlonega comes from the Cherokee language, it
   reminded me of something I studied last year in American history: the Trail of
   Tears. Is that in any way related to the, um, the gold rush in Georgia?
[Professor] That’s an excellent question. You’re absolutely right. It’s important to remember
   that the land where all of this gold was being discovered was actually Cherokee
   territory. The miners’ obsession with gold led to a lot of trespassing in Cherokee
   tribal lands, and this caused tensions to increase between the U.S. national
   government and the Cherokee nation. Q9(C) Eventually, the U.S. government
   became so desperate for the resources possessed by the Cherokee nation-
   I’m talking about the gold--that they actually seized the land. Q8 The
   government sent in the military in 1838 to forcibly remove the Cherokee
   people. But it was more than that...the Cherokees were actually forced to walk
   all the way from Georgia to Oklahoma. Four thousand of the 15,000 people
   who were made to take this journey died. For that reason, it is referred to as
   the, um, the Trail of Tears.
   OK. I don’t want to run out of time without discussing the California gold rush,
   so I’m afraid we have to move on now. The California gold rush began in much
   the same way as the Georgia gold rush--with someone finding gold...and
   madness ensuing. It was 1848, and the person who made the discovery was
   James Marshall. Three hundred thousand people caught gold fever this time
   around, coming from all over the world: Latin America, Asia, Europe, Australia...
   These people earned the nickname "forty-niners," because they arrived in 1849
   after hearing the news.
[Strident A] [Professor]...were there any negative effects of this gold rush? You know...like
   you mentioned about the one in Georgia.
[Professor] Well, yes, but first let me mention that some of the effects of the California
   gold rush were relatively beneficial. I mean, Q9(D) the state underwent a lot of
   growth, and new roads, churches, and schools were created to serve the new
   population. Q9(B) In addition, transportation was constantly improving, as
   people traveled west in steamships and by railroad.
   But, as I think you’re suggesting, some of the things that happened in Georgia
   occurred in California as well. I mean, the gold rush in California had a severely
   negative impact on the local Native American population. Disease, starvation,
   and violent attacks resulting from the gold rush caused their population to
   drop from 150,000 people in 1845 to 30,000 in 1870. The gold rush made
   many victims of other minorities as well. People from all kinds of different
   backgrounds were forced to compete for limited resources...and that turned
   some people against each other. Unfortunately, gold-rush boom towns were
   a lawless frontier, where racial tensions often escalated to violence. And there
   was no one to maintain order.